DETERMINATION OF EPIDEMIOLOGICAL FACTORS ASSOCIATED WITH BOVINE TUBERCULOSIS IN SELECTED LOCAL GOVERNMENT AREAS OF KATSINA STATE, NIGERIA

ABSTRACT

In a study to determine the knowledge, attitude and practices along with epidemiological factors of bovine tuberculosis from pastoralists and the communities around them in Katsina State, two Local Government Areas (LGAs) were randomly selected without replacement from each of the three Senatorial districts of the State. Furthermore, two wards from each of the selected LGAs were further randomly selected without replacement. Ten percent of the total estimated population of pastoralists in the State was used in the study. A closed-ended questionnaire was designed to capture the knowledge, attitude and practices of the respondents along with the epidemiological factors of the disease. A total of 592 respondents participated in the study with one hundred each from five of the LGAs and 92 from the sixth LGA. From the study 510 (86.0%) respondents indicated knowing 5 animal diseases each while 49 (8.27%) and 24 (4.05%)of them knew 10 and 15 animals diseases respectively. Among the diseases they knew were CBPP (43.70%), fasciolosis (21.90%), helminthosis (19.90%), black leg (8.70%) and FMD (3.80%). They attributed their sources of knowledge of these diseases to veterinarians (28.50%), human hospitals (6.70%), friends (4.56%), fellow herdsmen (3.37%) and the media (31.25%). Furthermore, 76.01% of the respondents were aware of bovine Tb and ascribed signs of the disease in both cattle and humans as coughing (61.48%), weight loss (20.60%), and death (15.20%). They demonstrated knowledge of the means of transmission of the disease in animals as ingestion (16.80%), drinking contaminated water (36.60%) and closeness (35.90%) among infected and susceptible animals and humans while means of transmission of the disease in humans to be consumption of contaminated meat (33.10%), drinking contaminated milk or milk products (36.48%) and closeness between infected and susceptible individuals (30.40%). With regard to their attitude to tuberculosis, 87.80% of the respondents indicated eating roasted meat (‗Suya‘) daily while others indicated drinking fermented milk (81.41%) and fresh milk from the udder (66.04%) of their cattle and that 64.80% of them considered that there was no adverse effect in taking milk directly from the udder of their animals. Among the respondents, 19.42% reported eating while milking their cattle as they (10.97%) regarded that there was no adverse effect in doing so. With regard to control of diseases in both animals and humans, they reported vaccinating their children against killer diseases like tuberculosis using BCG (44.08%), and they reported to the veterinary clinics (54.39%) when their animals were sick. With respect to their practices, 54.50% of the respondents reported keeping their animals under extensive management system while 8.70% and 36.60% of them reported keeping their animals under intensive and semi-intensive management systems respectively. Some of the respondents (19.50%) grazed their animals within 1km from their ‗Ruga‘ while 47.29% and 33.10% reported grazing their animals 2km and 3km away from their ‗Ruga‘ respectively. Some (40.37%) of the respondents reported that the distance between their ‗Buka‘ and the animals‘ kraals were 1 metre away from the kraal while others (30.40% and 14.80%) said their ‗Bukas‘ were 5metres and 10 metres away from the cattle kraals respectively.With respect to epidemiological factors to exposure to bTB, 72.97% of the respondents reported mixing their cattle with others from other herds daily and that 54.39% of the pastoralists reported all suspected diseases including bTB to veterinary clinics while 29.56% were sending such animals to markets for sale. From the study it was concluded that no less than 76.01% of the respondents were aware of tuberculosis in both animals and humans and that their attitude, practices along with the presence of epidemiological factors are capable of spreading tuberculosis within their areas and beyond.

CHAPTER ONE

1.0 INTRODUCTION

1.1 Background of the Study

The pastoralists, also known as Fulani herdsmen, are people who live mostly in remote areas and whose lives are primarily dependent on livestock (Saidu et al., 1991). Their occupation is mostly in tendering their livestock which comprise mostly cattle, sheep, and goats and to a certain extent poultry (Saidu et al., 1991; Kaltungo, 2013; Buhari, 2014). They may also have horses and/or donkeys which they use for haulage of their goods and children during migration (Saidu et al., 1991). They also participate in crop farming, providing the much needed manure for the crop farms while at the same time using their bulls to till the land (Saidu et al., 1991).

Diseases have been variously reported to affect efficient livestock development in many African countries to the effect that, in many situations, the European Union and the United States of America and other donors had to come to the aid of these countries (PARC, 1999). Some of these diseases include rinderpest, contagious bovine pleuropneumonia (CBPP) and foot and mouth disease (FMD). Diseases of public health importance like tuberculosis and brucellosis have also been reported to be widely spread among the national cattle herd and other animals in the Nigerian livestock industry (Abubakar, 2007; Kaltungo, 2013; Buhari, 2014; Baba, 2016). These diseases have been shown to occur in humans. For example, the organism (Brucella abortus) has been shown to cause orchitis in man. Similarly tuberculosis, due to Mycobacterium bovis, a primarily cattle disease agent, has been demonstrated in pastoralists and other community members in Bauchi and Gombe states recently (Ibrahim, 2016). This may not be unconnected with the cultural habits of most rural communities and even among some urban dwellers who take millet paste with unpasteurized milk in the form of ‗Nono (Ibrahim, 2016).

It is for these and other reasons that this study was designed to determine the knowledge, attitude and practices of pastoralists and communities where these pastoralists reside with regard to the epidemiology of tuberculosis in Katsina State.

1.2 Statement of Research Problem

Livestock production in Nigeria is largely in the hands of pastoralists who own greater than 80% of the national cattle herd (Saidu, et al., 1991). These pastoralists are in a habit of moving with their livestock from one area to another, especially during the dry season as they go out searching for crop residues for their livestock. It is also during this period that water for them and their livestock is scarce and this adds to the reason for their migration. In the process, many herds meet and this is capable of spreading diseases, especially communicable ones like tuberculosis. The level of education by these pastoralists has been shown to be low and therefore they are not aware of how diseases are necessarily transmitted or spread among animals (Saidu et al., 1991; Kaltungo, 2013;Buhari, 2014). The cultural activities of the pastoralists with regard to their eating and drinking habits has further added to the possibility for acquisition of infection and even the spread of such diseases like brucellosis and even tuberculosis, should the animals under their care be infected (Kaltungo et al,, 2013). Thus, today the prevalence of both tuberculosis and brucellosis seem to be on the increase (Alhaji, 1976; Abubakar, 2007; Bertu et al., 2010; Kaltungo, 2013).

Hitherto, Nigerian Governments depended greatly on oil for executing most of their activities in running governance. The present national administration is diverting its interest in making agriculture to contribute significantly to the Nigerian economy. Therefore, the livestock sector of agriculture should be seen to make greater impact in supporting the economy. This cannot be possible with increasing occurrence of livestock diseases and even zoonotic ones. Thus, determining the status of bovine tuberculosis in Katsina State will go a long way in making cattle to meaningfully contribute economically to the state and even national economy by way of increased supply of livestock products and productivity.

1.3 Justification

Nigeria is one of the countries in Africa with the highest livestock populations (Jahnke et al., 1986). However, other countries like Botswana and Kenya are able to tap from their livestock population more than Nigeria as they have substantially controlled livestock diseases (Jahnke et al., 1986). The potentials for increased and improved livestock production in Nigeria were there as there were many grazing reserves and stock routes that could facilitate livestock development(Saidu and Alhaji, 1981). There are also many extension delivery outlets that can educate the livestock keepers (pastoralists) to improve their production system (Dafwang, et al., 1987; Mijindadi and Saidu; 1990). However, diseases, especially zoonotic ones, are capable of not only reducing productivity of the national cattle herd but also adversely affecting the human population that will be expected to drive the economy of the nation around. This is at a time when many Nigerians have ventured into yoghurt production earning little income while Nigerians are able to receive dairy products as a means of improving the per caput animal protein intake, especially for the young and old members of the citizenry. The colonial administration along with the Regional Governments tried to introduce livestock development programmes like Livestock Investigation and Breeding Centres (LIBC) and dairy farms with the sole aim of boosting livestock production. This has become a thing of the past as the livestock owners are left more to themselves. There is, therefore, the urgent need to look into the diseases that, not only affect livestock, but also influence public health and productivity of both animals and man. Thus, this study is set out to determine the epidemiological factors that will lead to the spread of tuberculosis in selected Local Government Areas (LGAs) of Katsina State.

1.4 Aim and Objectives of the Study

The aim of the study was to determine the epidemiological factors associated with bovine tuberculosis in selected Local Government Areas of Katsina State, Nigeria

1.4.2 Objectives

  1. To determine the knowledge, attitudes and practices of pastoralists and rural communities in Katsina State on tuberculosis.
  2. To determine the epidemiological factors associated with bovine tuberculosis in selected Local Government Areas of Katsina State.
  3. To determine the risk factors of bovine tuberculosis with regard to pastoralists‘ and communities‘ attitudes and practices in selected Local Government Areas of Katsina State.

1.4.3 Research Questions

  1. What are the knowledge, attitudes and practices of pastoralists and rural communities with regard to bovine tuberculosis in Katsina State?
  2. What are the epidemiological factors associated with bovine tuberculosis in selected Local Government Areas of Katsina State?
  3. What are the risk factors of bovine tuberculosis with regard to pastoralists‘ and communities‘ attitudes and practices in selected Local Government Areas of Katsina State?
DETERMINATION OF EPIDEMIOLOGICAL FACTORS ASSOCIATED WITH BOVINE TUBERCULOSIS IN SELECTED LOCAL GOVERNMENT AREAS OF KATSINA STATE, NIGERIA

COMPARATIVE EFFICACY STUDY OF DIMINAZENE ACETURATE, KAEMPFEROL AND THEIR COMBINATION ON EXPERIMENTAL TRYPANOSOMA BRUCEI BRUCEIINFECTION IN MICE

Abstract

In this study, the comparative efficacy study of kaempferol, diminazene aceturate and their combination against experimental Trypanosoma brucei brucei infection in mice was determined. Thirty six adult swiss albino mice both sexes weighing between 18 and 22 grams were randomly divided into six groups (I, II, III, IV, V and VI) of six mice each. Mice in group I were neither treated nor infected (un-infected, normal control). Mice in group II were pre-treated prophylactically with kaempferol (1 mg/kg per os) for 14 consecutive days prior to infection. Mice in groups II to VI each were inoculated with blood containing Trypanosoma brucei brucei (106 trypanosomes/ml of blood/animal) intraperitoneally (I.P). Following detection of parasitaemia, mice in group III were treated once with diminazene aceturate (3.5 mg/kg) I.P only. Mice in group IV were treated with diminazene aceturate (3.5 mg/kg) once I.P, and then continued with kaempferol (1 mg/kg per os) for nine consecutive days. Mice in group V were treated with kaempferol (1 mg/kg per os) only for nine consecutive days. Mice in group VI were given normal saline (5 ml/kg per os) only for nine consecutive days. Nine days post-infection, all mice were sacrificed by severing their jugular veins, blood samples were collected for haematological and biochemical analyses, while tissue samples were collected for histopathological examination. The results obtained showed significant differences between the levels of parasitaemia and survival rate of mice in groups II and VI. Following infection with Trypanosoma brucei brucei mean packed cell volume, haemoglobin concentration and red blood cell count significantly (P < 0.05) decreased in groups II and VI when compared to groups III, IV and V. Similarly, Mean corpuscular volume and mean corpuscular haemoglobin concentration significantly (P < 0.05) decreased in groups II and VI when compared to groups III, IV and V. The percentage of red blood cell haemolysis at 0.5%, 0.7% and 0.9% NaCl concentrations was significantly (P < 0.05) higher in groups II and VI when compared to groups III, IV and V.

Total leucocyte count significantly (P < 0.05) decreased in groups II and VI when compared to groups III, IV and V. The mean lymphocytes and neutrophil count reduced significantly (P < 0.05) in groups II and VI when compared to groups III, IV and V. There were significant (P < 0.05) increases in the mean alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase in groups II and VI when compared to groups III, IV and V. Antioxidant enzymes; superoxide dismutase, catalase and glutathione peroxidase increased significantly (P < 0.05) in groups III, IV and V when compared to groups II and VI. Serum level of malondialdehyde significantly (P < 0.05) increased in groups II and VI when compared to groups III, IV and V. In conclusion, kaempferol possesses antitrypanosomal activity and probably stimulate host immunity to control the proliferation of the parasite in the blood.

CHAPTER ONE

1.0 INTRODUCTION

1.1 Background of the Study

Trypanosomosis is a disease caused by the protozoan parasite from genus Trypanosoma and transmitted by the tse- tse fly (Glossina species) and other biting flies (Masocha et al., 2012), making the incidence of the disease to be of great concern in the tropics (Anosa et al., 1983). The trypanosomes which affect both man and animals have been subdivided into two, namely the haematic groups (Trypanosoma congolense and T. vivax) which always remain in the plasma of the host‘s blood and the tissue invading group (T.brucei, T.evansi, T.rhodesiense, T.gambiense and T. equiperdum) which are found extravascularly and intravascularly (Anosa et al., 1977).

African animal trypanosomosis or nagana is a disease caused by T. congolense, T. vivax and T. brucei spp. In wild animals, these parasites cause relatively mild infections while in domestic animals they cause a severe, often fatal disease (Molyneux et al., 1996). All domestic animals can be affected by nagana and the symptoms are fever, listlessness, emaciation, hair loss, discharge from the eyes, oedema, anaemia, and paralysis (Masocha et al., 2012). As the illness progresses the animals become progressively weak and eventually become unfit for work, hence the name of the disease “N’gana” which is a Zulu word that means “powerless/useless” (Molyneux et al., 1996). Because of nagana, stock farming is very difficult within the tsetse belt. The available means of control involves tsetse control, chemoprophylaxis, chemotherapy and use of trypanotolerant livestock. At present, control of trypanosomosis is chiefly done by chemotherapy and chemoprophylaxis using the following drugs: Diminazine, Homidium, and Isometamidium (Leach and Roberts, 1981; ILRAD Reports, 1990). Diminazene aceturate is probably the most commonly used therapeutic agent for trypanosomosis in livestock in Sub-Saharan Africa (Geerts and Holmes, 1998), even in Nigeria. However, complete dependence on drugs in many situations of trypanosomosis has been hampered in many areas by their toxic effects, high cost and frequent development of resistance to these drugs by the parasites. This is considered a very serious problem in trypanosomosis control in Africa (Geerts and Holmes, 1998). This results from the fact that the drugs effectively eliminate the parasites from the blood stream and the animal appears recovered, and then undergoes relapse infection which may be characterized by severe neurological infection leading to the death of the affected animal. In Nigeria, the occurrence of drug resistance to available trypanocides has been attributed to the presence of fake drugs, abuse of the existing drugs and inadequate dosing of the drugs in trypanosomosis therapy (Ezeokonkwo et al., 2010). Therefore, the current challenge to the majority of African pastoralists is to optimize the use of the relatively old existing drugs (Ezeokonkwo et al., 2010). In view of this, the use of drug combinations, new therapeutic regimens and the use of Slow Release Devices (SRD) of existing trypanocides have been suggested (Geerts and Holmes, 1998).

Secondary metabolites in plants including flavonoids are responsible for a variety of pharmacological activities (Mahomoodally et al., 2005; Pandey, 2007), recent interest in these substances has been stimulated by the potential health benefits arising from the antioxidant activities of these polyphenolic compounds (Pandey, 2007). The beneficial health effects of flavonoids have also been related to their antioxidant, anti-inflammatory, antiestrogenic, cardioprotective, cancer chemopreventive, neuroprotective, antidepressant and anxiolytic effects (Butterweck et al., 2000).

Kaempferol is a natural flavonol, a type of flavonoid, found in a variety of plants and plant-derived foods. Kaempferol acts as an antioxidant by reducing oxidative stress. Many studies suggest that kaempferol may reduce the risk of various cancers, and it is currently been studied for possible treatment of cancer (Leopoldini et al., 2006).

COMPARATIVE EFFICACY STUDY OF DIMINAZENE ACETURATE, KAEMPFEROL AND THEIR COMBINATION ON EXPERIMENTAL TRYPANOSOMA BRUCEI BRUCEIINFECTION IN MICE

AMELIORATIVE EFFECTS OF KAEMPFEROL AND ZINC GLUCONATE ON HAEMATOLOGICAL, NEUROBEHAVIOURAL AND OXIDATIVE STRESS CHANGES IN WISTAR RATS EXPOSED TO NOISE STRESS

ABSTRACT

The aim of the study was to investigate effects of kaempferol and zinc gluconate administration on haematological, neurobehavioural and oxidative stress changes in Wistar rats, exposed to noise stress. Thirty (30) rats were randomly divided into five groups: Groups I and II were administered with deionised water; Group III, kaempferol; Group IV, zinc gluconate; Group V, kaempferol + zinc gluconate for 36 days. Groups II, III, IV and V were subjected to noise stress of 100 dB dose for 15 days from day 22 to day 36. Behavioural activities were assessed on days 1, 8 and 15 after noise exposure. The effects of the different treatments on body weight change, open-field activities, neuromuscular coordination, motor strength, excitability scores, sensorimotor reflexes and learning and memory were assessed in the rats. Packed cell volume, haemoglobin concentration, total erythrocyte count, erythrocytic indices, platelet count neutrophil/lymphocyte ratio, total and differential leucocyte counts and erythrocyte osmotic fragility (EOF) test were determined using standard methods. The brain was used to evaluate noise stress-induced lipoperoxidative changes, through determination of brain malondialdehyde (MDA) concentration and activities of antioxidant enzymes such as catalase, superoxide dismutase and glutathione peroxidase, using kits. The results of this study showed that noise stress-induced decrease in body weight gain was significantly (P < 0.05) ameliorated in the group treated with kaempferol + zinc (123.70 ± 0.99 g, 133.70 ± 1.59 g) than in the group treated with deionised water + noise (117.70 ± 1.02 g, 125.70 ± 1.20 g). There was a significant and consistent decrease in the EOF of rats treated with kaempferol + zinc. Kaempferol + zinc gluconate significantly (P < 0.05) ameliorated decrease in haemoglobin concentration (from 12.62 ± 0.12 to 14.32 ± 0.11 g/dL), packed cell volume (from 37.85 ± 0.35 to 43.47 ± 0.30 %) and erythrocyte counts (from 6.43 ± 0.04 to 7.20 ± 0.06× 1012/L). Values of mean corpuscular haemoglobin (20.40 ± 0.33 ρg) and mean corpuscular haemoglobin concentration (33.20 ± 0.15%) were significantly (P< 0.05) higher in kaempferol + zinc treated rat compared to the deionized water + noise treated group (18.43 ± 0.34) and (29.65 ± 0.89) respectively. Rats treated with zinc had the highest mean corpuscular volume (61.35 ± 0.67 fL) compared to the deionized water + noise treated group (58.87 ± 0.29). Platelet counts were also significantly higher (P < 0.05) in rats treated with kaempferol + zinc (609.20 ± 6.90 x 106 g/dL) compared to the group treated with noise + deionised water (439.80 ± 7.91 x 106 g/dL). Administration of kaempferol + zinc caused leucocytosis due to neutrophilia and lymphocytosis as well as a significant (P < 0.05) decrease in N:L ratio (0.25 ± 0.01) than in the group treated with deionised water + noise (0.35 ± 0.03). Combination kaempferol + zinc significantly (P < 0.05) enhanced learning (from 2.33 ± 0.33 s to 1.17 ± 0.17) and memory (from 92.17 ± 4.08 s to 106.80 ± 2.14 s). Kaempferol + zinc significantly (P < 0.05) mitigated noise stress induced impairment in neuromuscular coordination neuromuscular coordination (from 45.0 ± 1.43o to 65.06 ± 1.23o), motor strength (from 51.68 ±229 s 78.33 ± 5.69 s), sensory motor reflex (from 2.88 ± 0.16 to 4.83 ± 0.17), and motor coordination on days 1, 8 and 15 (from 10.83 ± 1.40 cm, 11.5 ± 1.18 cm, 10.50 ± 0.923 cm to 5.33 ± 1.45 cm, 4.33 ± 1.41 cm and 4.83 ± 1.35 cm) respectively. Kaempferol + zinc exerted anxiolytic effects, demonstrated in treated rats subjected to open-field test. In addition, combined treatment significantly (P < 0.05) decreased malondialdehyde (MDA) concentration (from 1.10 ± 0.20 nmol/mg to 0.70 ± 0.20 nmol/mg) and enhanced activities of antioxidant enzymes: catalase (from 32.50 ± 2.20 IU/L to 36.90 ± 2.00 IU/L), glutathione peroxidase (from 25.10 ± 1.10 IU/L to 29.40 ± 1.20 IU/L) and superoxide dismutase (from 1.80 ± 0.20 IU/L to 2.20 ± 0.30 IU/L). In conclusion, treatment with kaempferol and zinc singly and in combination ameliorated noise-induced haematological, neurobehavioral and oxidative stress changes in Wistar rats.

CHAPTER ONE

1.0 INTRODUCTION

1.1 Background of the Study

Noise is derived from the Latin term “nausea” and has been defined as unwanted sound, which is a potential hazard to communication and health (Ismaila and Odusote, 2014). Stress refers to a non-specific response of the body to unpleasant stimuli, threatening homeostasis and the integrity of the organism (Wankhar et al., 2014; Munne-Bosch and Pinto-Marijuan, 2017). It is a state of threatened homeostasis provoked by psychological, physiological and environmental stressors (Zhang et al., 2015). Noise is measured in decibel (dB) units (Ismaila and Odusote, 2014). Wang et al. (2016) reported that noise exposure is a potent stressor as it increases the levels of the stress hormone, corticosterone. Noise pollution, especially in the urban environment, is on the increase (Öhrström et al., 2006; Michaud et al., 2016; WHO, 2016) and ranks among the environmental stressors with the highest public health impact (WHO, 2016). The auditory effects include hearing impairment and permanent hearing loss due to excessive noise exposure. The non-auditory effects include stress-related, physiological and behavioural effects.

Noise stress induces increased reactive oxygen and nitrogen species (ROS and RNS) generation, which are capable of breaking down lipid and protein molecules and damaging DNA, triggering loss of function and cell death (Henderson et al., 2006; Zhang et al., 2015). The ROS also trigger apoptosis by activating proapoptotic mitogen activated protein (MAP) kinase-signaling pathways (Tao et al., 2015). Oxidative destruction has been associated with ROS-induced diseases (Messarah et al., 2011). Antioxidants are molecules that inhibit and scavenge ROS/RNS and convert them to less dangerous molecules (Michael and Peter, 2015).

1.2 Statement of Research Problem
Noise-induced hearing loss has global implications, with 10 million adults and 5.2 million children in the US, and 250 million people world-wide having a noise-induced hearing loss greater than 25 dB; a clinically significant hearing loss (Tao et al., 2015). Additionally, occupational noise accounts for 16% of the disabling hearing loss in adults world-wide, resulting in decreased economic production (Baliatsa et al., 2016). Nocturnal environmental noise also provokes measurable metabolic and endocrine perturbations, including secretion of adrenaline, noradrenaline, cortisol, increased heart rate and arterial blood pressure, and increased motility. While asleep, these biological responses to noise are mostly unnoticed (Basner and Samel, 2004, 2005; Selander et al., 2009). Data confirm that exposure to traffic noise, not specifically at night, is associated with increased incidence of diabetes mellitus (Sorensen et al., 2013), hypertension (Babisch and Kamp, 2009), stroke among the elderly (Sorensen et al., 2011), and mortality from coronary heart disease (Selander et al., 2009; Sorensen et al., 2011; Floud et al., 2013; Baliatsa et al., 2016).

According to WHO (2016), noise causes health damage every day estimated at 4 million dollars. Moreover, psychoneurotic and psychosomatic complaints are also observed due to noise exposures (Martinho et al., 1999). Zheng and Ariizumi (2007) reported that noise exposure prolongor delays healing of surgical wounds, while three days of noise exposure increases immune function, but 28 days of its exposure suppresses it. In addition, oxidative stress increases in rats subjected to 28 days of noise stress, suggesting that oxidative status at least partially accounts for the immune suppression (Cheng et al., 2011). In farm animals, noise directly affects reproductive physiology and energy consumption (Brouček, 2014). Noise may also have indirect effects on population dynamics through changes in habitat use, courtship and mating, reproduction and parental care (Rabin et al., 2003). Pigs exposed to 90 dB prolonged or intermittent noise resulted in decrease in growth (Otten et al., 2004). When poultry is exposed to intermittent loud noise, egg laying and growth rate decreases while mortality increases (Oh et al., 2011). Losses have been reported from mink farms in the form of premature births, insufficient lactation and females kill their offspring in connection with exposure to sonic booms (Algers et al., 1978). In cattle, exposure to a high-intensity noise (105 dB) results in decrease feed consumption (appetite reduction), milk yield, and effectiveness of the milk ejection reflex (Cwynar and Kolacz, 2011).

Noise-induced hearing loss is the greatest cause of sensory disability (WHO, 2016), affecting up to 1 in 6 of the population. It is estimated that approximately 20% of the burden is generated from excessive noise exposure in occupational and leisure settings (Thorne et al., 2008). Sustained exposure to sound pressure levels greater than 85 dB, or sudden exposure to impulse noise leads to irreversible damage to the sensory structures of the cochlea. Once damaged, the mammalian sensory hair cells do not regenerate, and the loss of hearing is permanent (WHO, 2016).

AMELIORATIVE EFFECTS OF KAEMPFEROL AND ZINC GLUCONATE ON HAEMATOLOGICAL, NEUROBEHAVIOURAL AND OXIDATIVE STRESS CHANGES IN WISTAR RATS EXPOSED TO NOISE STRESS

CLINICAL MANIFESTATIONS, BLOOD PARAMETERS, RESPONSE TO TREATMENT OF NATURALLY OCCURRING CASES OF BOVINE TRYPANOSOMOSIS IN NIGER STATE, NIGERIA

ABSTRACT

A longitudinal study was conducted to assess the clinical manifestation, response to treatment, and biochemical alterations to bovine trypanosomosis in some selected Local Government Areas of Niger State. A total of 343 cattle from thirty nine (39) herds were examined for infection with trypanosomes. Parasitological, haematological and biochemical tests were carried out on their blood and serum samples. Clinical signs, changes in haematological and biochemical values were monitored post treatment with diminazene aceturate and isomethamidium chloride. The most prevalent clinical signs observed were emaciation (75%), weakness (71%) intermittent anorexia (65%), pale mucous membrane (58%), epiphora (45%), and dark/rough hair coat (41%). Three species of trypanosomes were identified in the infected animals, Trypanosoma vivax (5.5%), T. congolense (5.5%), and T. brucei (2.0%). The mean body weights of infected animals (257.94 ± 74.13kg) were significantly lower than that of the control (386.96 ± 62.69kg). The mean rectal temperature of infected animals (39.82 ± 1.79ºC) differed significantly from the control (38.490.84ºC) (P<0.05). The mean PCV (23.27 ± 6.82%), platelet (93.23 ± 42.02 x103 μl), and total leukocyte counts (4.40 ± 1.64×103 μl) of infected cattle before treatment were significantly lower than those of the control (32.47 ± 8.35%, 209.67 ± 55.75 x103 μl and 8.14 ± 3.34 x103 μl respectively). Lymphocyte counts (64.64 ± 12.19%) were significantly higher in the infected cattle when compared to the control (58.19 ± 15.29%). The mean neutrophils count (32.62 ± 12.25%) of the infected cattle was significantly lower than the control (39.46 ± 15.05%). The mean values of Alanine amino transferase (34.62 ± 20.57 IU/L), alkaline phosphatase (105.48 ± 37.97 IU/L), Creatinine kinase (265.71 ± 21.25 IU/L) of the infected cattle were significantly higher than the control (16.60 ± 3.73 IU/L, 65.60 ± 18.90 IU/L, and 254.12 ± 11.32 IU/L respectively). The mean total proteins (51.50 ± 18.28 mg/dL), glucose (31.94 ± 13.68 mg/dL), cholesterol (2.62 ± 1.33 mg/dL) of the infected cattle were significantly lower than the control (77.20 ± 14.46 mg/dL, 46.80±13.59 mg/dL, 3.25 ± 1.66 mg/dL) respectively. The levels of albumin (24.84 ± 8.31 mg/dl) and globulins (29.34 ± 15.31 mg/dl) of the infected cattle were significantly lower than the control (27.60 ± 6.73 mg/dL and 49.80 ± 15.05 mg/dL) respectively. The mean triglycerides levels of the infected cattle (2.32 ± 1.08 mg/dL) were significantly higher than the control (1.90 ± 0.58 mg/dL). The mean levels of sodium (111.82 ± 28.84 mg/dL), chloride (91.76 ± 25.59 mg/dL) and bicarbonates (17.46 ± 6.76 mg/dL) of the infected cattle were significantly lower than the control (127.80 ± 34.95 mg/dL, 98.60 ± 19.48 mg/dL, and 20.6012.58 mg/dL) respectively. The levels of calcium (2.98 ± 0.84mg/dL), iron (1.55 ± 0.60 mg/dL), copper (0.49 ± 0.36 mg/dL) and zinc (2.08±1.42 mg/dL) were significantly lower in infected cattle compared to the values of the control (4.16 ± 0.54 mg/dL, 4.45 ± 2.07 mg/dL, 0.81 ± 0.08 mg/dL, and 7.88 ± 2.52 mg/dL) respectively. All values were held at P≤0.05 confidence interval. This study has suggested for the first time the clinical signs of natural cases of trypanosomosis in cattle in selected Local Government Areas in Niger State. Diminazene aceturate and isomethamidium chloride were effective in the treatment of naturally occurring trypanosomosis. However, relapse infection was observed using both drugs. The study has shown that the current trend in diagnosis, treatment and management of trypanosomosis is important to avoid treatments that will potentiate drug resistance. Further work should be done to establish the parasitological and pathological bases for each of the clinical signs that were observed in this study.

CHAPTER ONE

INTRODUCTION

1.1 Background to the study

Trypanosomosis is a complex disease caused by trypanosomes, a group of unicellular protozoan parasites found in the blood and other tissues of vertebrates including livestock, wildlife (Tesfaye, 2002) and man (Franco et al., 2014). The disease is commonly known as “Nagana”, “Samore” or Tsetse fly disease in the bovines (Radostits et al., 2006), and sleeping sickness in man (Franco et al., 2014).The disease is characterized by anorexia, anaemia, diarrhoea, excessive epiphora, emaciation, weakness and eventual death, in addition to leucopaemia, thrombocytopaenia, serum biochemical changes and lesions in some tissues and organs (Igbokwe, 1989; Esievo and Saror, 1991; Uilenberg, 1999; Rodosttis et al., 2006).

The most important trypanosome species infecting livestock are Trypanosoma (T) congolense, T. vivax and T. brucei, primarily for ruminants (Igbokwe, 1995; Onyiah, 1997; Takeet et al., 2013) and T. simiae which primarily infects pigs (Sarkey, 1998). Trypanosoma evansi and T. equiperdum infects equidae (Moloo et al., 2000; Getachew, 2005; OIE, 2013) while Trypanosom brucei rhodesiense and T. brucei gambiense are known to infect man (Dumas et al., 1999; Franco et al., 2014). Trypanosomes are commonly transmitted biologically by tsetse flies (Glossina SPP), but some cases of mechanical transmission by other haematophagus flies and trans-placental transmission have been reported (Ikede and Losos 1972; Ogwu et al., 1986).

Trypanosomosis is widespread and endemic in Nigeria, occurring in all areas infested by tsetse flies (Onyiah et al., 1983) as well as the tsetse-free arid zones of the north that is infested by other biting flies (Nawathe et al., 1988, 1995; Ahmed et al., 1994).

The tsetse flies are found between latitudes 14ºN and 29ºS covering about 10 Million km² stretching across 37 countries in Africa (Seifert, 1996; WHO, 1998; Mulumba, 2003).

1.2 Statement of the Research Problem

The annual production losses due to Africa Animal Trypanosomosis (AAT) morbidity and mortality are valued at $4.5 billion across Africa while the indirect annual costs of AAT are estimated to be $134 billion (Kristjanson et al., 1999; Fadiga et al., 2013). In the Sub Saharan Africa over 3 million cattle and other domestic livestock are lost annually through deaths caused by trypanosomosis (ILRAD, 1990; Mulumba, 2003; Abenga et al., 2003; FAO, 2005). The disease costs the Nigerian economy $135 million per annum due to its negative effects on weight gain, growth rate, milk yield, reproduction in cattle and discouragement of the use of draught animals in arable farming (Omotainse et al., 2004).

Trypanosomosis has been shown to reduce calving rates by 11-20% and increases calf mortality by 10-20% in susceptible breeds of cattle. Similarly, it is known to reduce milk off take in trypanotolerant breed of cattle by 10-20% and off take for sale or slaughter by 5–30%. The work performance of draught oxen in susceptible cattle can drop by 38% in high risk areas (PAAT, 2000; Shaw, 2004). Generally, trypanosomosis reduces total stock of livestock by 10–60% (Kristjanson et al., 1999; PAAT, 2000; Gilbert et al., 2001) with consequent reduction in meat and milk output by 50% and reduction in total agricultural production by 2–10 per cent (PAAT, 2000). Trypanosomosis is one factor that has constrained the development of specialized dairy enterprises in sub Saharan Africa (Swallow, 2000). The overall impact of the disease extends from restricted access to fertile and cultivable areas, imbalances in land use and exploitation of natural resources and compromised growth and diversification of crop-livestock production systems (Mattioli et al., 2004).

1.3 Justification of the Study

The management of clinical disease due to trypanosomes through diagnosis and treatment remains difficult under field conditions (Nantulya, 1990; Schlater and van den Bossche, 2004), because of its protean manifestations and lack of pathognomonic signs (Eisler et al., 2004; Rodostits et al., 2006).Simultaneous infections with more than one Trypanosoma species (Nyeko et al., 1990) and their ability to co-infect with other parasites (Babesia spp., Theileria spp., Anaplasma spp., Ehrlichia spp., and helminths) (Thumbi et al., 2014) further complicate the prognosis and clinical manifestations of the disease (Van Wyk et al., 2014). It has also been estimated that close to 50% of all cases of trypanosomosis are not diagnosed and a large proportion of the infected animals remained untreated (Picozzi et al., 2002). Poor and inadequate tools for the diagnosis of the disease in the field make it difficult to conclude which clinical signs are attributable to a given parasite (Machila, 2004).

There is the need therefore to document clinical signs due to natural Trypanosoma infection with the view aiding field personnel and farmers in the recognition of animals suffering from the disease in the field to enable rapid and accurate diagnosis of the disease and subsequent monitoring of the incidence of infection. This would assist in management decisions; provide basis for disease surveillance, monitoring and control programmes. It will also assist in the control and eradication of tsetse and trypanosomosis which would eventually benefit and promote human and livestock health, diversify agricultural production and allow for optimum exploitation of the abundant fodder and water resources for large scale livestock production.

1.4 Aim of the Study

The aim of the study was to determine the clinical manifestations, blood parameters, response to treatment of naturally occurring cases of bovine trypanosomosis in Niger State, Nigeria.

1.5 Objectives of the Study

The objectives of the study were to:

i. Determine the species of trypanosomes infecting cattle in Niger State

ii. Determine the clinical signs naturally infected cattle manifest in Niger State, Nigeria;

iii. Determine the haematological and serum biochemical parameters in the naturally infected cattle in Niger State, Nigeria;

iv. Evaluate the treatment response to selected trypanocides by naturally infected cattle during the study period in Niger State, Nigeria.

1.6 Research Questions

i. What are the species of trypanosomes infecting cattle in Niger State?

ii. What are the commonly observed clinical signs that naturally infected cattle manifest in Niger State, Nigeria?

iii. What are the haematological and serum biochemical profiles of natural trypanosomosis in cattle in Niger State, Nigeria?

CLINICAL MANIFESTATIONS, BLOOD PARAMETERS, RESPONSE TO TREATMENT OF NATURALLY OCCURRING CASES OF BOVINE TRYPANOSOMOSIS IN NIGER STATE, NIGERIA

EVALUATION OF PLATELET–DERIVED AND EPIDERMAL GROWTH FACTORS ON SURGICALLY-INDUCED WOUNDS IN NEW ZEALAND WHITE RABBITS TREATED WITH METHYLPREDNISOLONE

ABSTRACT

The study was designed to evaluate the influence of platelet-derived growth factor (PDGF-AB) and epidermal growth factor (EGF-AB) on modulating wound healing of rabbits. A total of twenty four (24) New Zealand White rabbits of nine months to one year old from both sexes were used for the study.

The rabbits weigh between 1.5–2.0 kg body weights. The rabbits were randomly grouped into two major groups (1 and 2) of twelve rabbits each. The rabbits were treated parenterally with methylprednisolone (methylP), and compared with the control treated parenterally with normal saline (NS). They were subsequently placed randomly, into four sub-groups each 1A (methylP + EGF), 1B (methylP + PDGF), 1C (methylP + NS) and 1D (methylP + EGF + PDGF); 2A (NS + EGF), 2B (NS + PDGF), 2C (NS + NS) and 2D (NS + EGF + PDGF) of three rabbits each.

The animals were pre-anaesthetised with atropine sulphate and chlorpromazine. Ketamine hydrochloride was used for anaesthesia. An area of wound that is 2 cm × 1 cm dimension on rabbit dorsum, was created on each site of the dorsum. Group 1 were treated parenterally with methylP 0.5 mg/kg and the sub-groups were treated topically with 1A (EGF), 1B (PDGF), 1C (Normal saline) and 1D (EGF + PDGF).

Group 2 were parenterally treated with normal saline and topically with 2A (EGF), 2B (PDGF), 2C (Normal saline) and 2D (EGF + PDGF). Each wound designated for PDGF, EGF and NS were smeared with 2.92 µg of PDGF, 20.8 µg of EGF, and 0.2 mL of normal saline, respectively. The wounds were monitored until complete healing.

Doppler ultrasound of the scar tissue was carried out at the frequency of 5 Hz using C5 sonostar laptop ultrasound. Blood, serum and wound biopsy were taken. Wound retraction was recorded in all the groups with highest peak in NS + PDGF (3.13 cm2) at day 3 and 3.11 cm2 in NS + NS at day 5. Onset of epithelialisation was recorded at day 7 except for groups treated with EGF + PDGF the recorded epithelialisation at day 5 post-wounding.

Inflammatory cells influx were diffused in the NS + NS and NS + EGF + PDGF groups. However, synergy in anti-inflammatory activity was not recorded with the use of methylP + PDGF but was observed on methylP + EGF. The PDGF group showed superior anti-inflammatory activity compared to the EGF treated rabbits. Ultrasonography of NS + NS scar line showed hyper-echogenicity with least vascular perfusion but small scar lines in the EGF and PDGF treated rabbits.

The methylP + PDGF and methylP + EGF rabbits had the strongest scar strength as recorded by the tensile strength of 76.8 N/cm2 and 71.25 N/cm2, respectively. In conclusion, the overall healing time of methylprednisolone-treated rabbits was delayed; however the scar had the best connective tissue fibre arrangement.

Reduced period of wound retraction was achieved with the use methylprednisolone, EGF or PDGF, thus, reduced wound surface area for contamination and reduced chances of wound infection. Smallest scar size was achieved with the use of PDGF and methylP + PDGF, thus, maybe important in cosmetic surgeries.

The administration of methylprednisolone at 0.5mg/kg in wound management to enhance collagen fibre arrangements in scar tissue. Tensile strength was best observed in methylP + PDF and methylP + EGF, thus, are relevant in management of wounds in a weight carrying regions like the ventral aspects of the abdomen. The place of proper wound dressing in wound healing management cannot be replaced.

REFERENCES

Abcam manual. (2017). ab100504-EGF-Human-ELISA-Kit-ab100504-protocol-plain-v2.pdf. Retrieved 16/03/2017.

Abcam manual. (2017). ab100623-PDGF-Human-ELISA-Kit-ab100623-protocol-plain-v2.pdf. Retrieved 16/03/2017.

EVALUATION OF PLATELET–DERIVED AND EPIDERMAL GROWTH FACTORS ON SURGICALLY-INDUCED WOUNDS IN NEW ZEALAND WHITE RABBITS TREATED WITH METHYLPREDNISOLONE

EVALUATION OF ANTICOCCIDIAL PROPERTIES OF THE METHANOL ROOT-BARK EXTRACT OF ANNONA SENEGALENSIS PERS. IN BROILERS EXPERIMENTALLY INFECTED WITH EIMERIA TENELLA

ABSTRACT

The study was conducted to evaluate the effect of methanol root-bark extract of Anonna senegalensis against experimental Eimeria tenella infection in broiler chickens on the basis of performance (weight gain) and pathogenicity (oocyst production, lesion score and percentage mortality).

Phytochemical screening and acute toxicity studies of the extract were carried out using standard methods. Forty-two chicks were randomly assigned to seven experimental groups of six birds each. The experimental design included positive (infected untreated and negative (uninfected untreated) control groups.

Groups 1- 6 were inoculated orally with 2 × 104 sporulated oocysts at the 14th day of age except uninfected untreated group. In vitro anticoccidial activity test was performed by observing the effect of the extract on oocyst sporulation.

Oocysts count was done on 5th, 6th 7th and 8th 9th day after infection. Record of mortality was kept and postmortem of dead birds and lesion score were also performed. The phytochemical analysis of the methanol extract revealed the presence of alkaloids, tannins, saponins, glycosides, flavonoids, cardiac glycosides, steroid and terpenoids.

Acute toxicity study of the extract revealed that the LD50 methanol root bark of the extract of Anonna senegalensis (MREAS) is more than 5000 mg/kg . Inhibition of oocyst sporulation in vitro depended on the concentration of the extract, being highest at the maximum concentration of the extract.

Chicks medicated with A. senegalensis extract attained higher body weight than the non medicated challenged group. The highest mean weight gain after challenge with E. tenella at 42 days of age was high in group 5 (1450g). Lesion scores were significantly reduced in groups 4 and 5 (Group treated with 1600 mg/kg and amprolium), while groups 1 and 2 (200mg/kg and 400mg/kg treated groups) showed slight improvement in comparism with the former. Mortality of 5.5%, 2.8%. 2.8% and 16.6% was recorded for groups 1, 2, 3 and 6 respectively.

Histopathological findings revealed haemorrhages in the caeca, cellular infiltration, presence of endogenous parasitic stage and desquamation of epithelia. The oocysts output per bird in the treated groups were lower than that in the challenged control group. The reduced oocysts output at 1600 mg/kg dose level suggested that A. senegalensis could be beneficial for management and control of coccidiosis in broilers. This anticoccidial effect of the extract was, however, lower than those exhibited by amprolium.

REFERENCES

Abbas,R., Colwell, D.D., Gilleard, J.(2012). Botanicals: an alternative approach for the control of avian coccidiosis.World’s Poultry Science Journal 2012;68:203-215.

EVALUATION OF ANTICOCCIDIAL PROPERTIES OF THE METHANOL ROOT-BARK EXTRACT OF ANNONA SENEGALENSIS PERS. IN BROILERS EXPERIMENTALLY INFECTED WITH EIMERIA TENELLA

EFFECTS OF QUERCETIN ON SOME PHYSIOLOGICAL PARAMETERS AND PERFORMANCE OF BROILER CHICKENS RAISED AT DIFFERENT STOCKING DENSITIES

ABSTRACT

The study investigated the effects of a potent antioxidant, quercetin, on some physiological parameters, performance, and carcass and meat pH in broiler chickens, raised at different stocking densities. A total of 60 one-day-old Ross 308 broiler chicks were randomly assigned to four treatment groups based on stocking density (12 birds/m2 or 18 birds/m2) and 50 mg/kg body weight quercetin treatment (quercetin-treated or untreated).

Quercetin was administered per os once daily for 28 consecutive days at 18:00 h. The stocking density of 12 birds/m2 was categorised as low stocking density (LSD) condition while 18 birds/m2 represented high stocking density (HSD) condition. The circadian cloacal temperature was recorded at 2 h interval, three times, one-week apart on days 22, 29 and 36 while the haematological profile and erythrocyte osmotic fragility (EOF) were recorded on days 28, 35 and 42.

Broiler performance was recorded daily. The carcass characteristics and meat pH was determined at the end of the study period. Fluctuations in diurnal cloacal temperature (CT) showed that increasing stocking density induced an elevation (P < 0.05) in the overall mean CT of untreated HSD group (40.96 ± 0.02 ºC) while the CT was lower (P < 0.05) in the treated HSD group (40.72 ± 0.02 ºC). The CT of the untreated LSD group (40.88 ± 0.02 ºC) was lower (P < 0.05) when compared with the untreated HSD group (40.96 ± 0.02 °C). On day 28, the total white blood cell count (TWBC), heterophils and H:L ratio (8.50 ± 0.67 x 109/L, 1.35 ± 0.30 x 109/L and 0.19 ± 0.03 respectively) were significantly lower (P < 0.05) in the quercetin-treated HSD group when these parameters were compared with those of the untreated HSD group (12.36 ± 1.22 x 109/L, 3.91 ± 0.79 x 109/L and 0.53 ± 0.13 x109/L respectively). The overall mean variation in percentage erythrocyte osmotic fragility (EOF) was significantly higher (P < 0.05) at 0.5 %, 0.3 % and 0.1 % NaCl concentrations in the quercetin-treated LSD group with corresponding values of 10.29 ± 6.09 %, 67.41 ± 3.30 % and 88.93 ± 3.47 % respectively, while the EOF was 0.24 ± 0.16 %, 62.21 ± 4.22 % and 85.50 ± 3.56 % in the untreated LSD group. HSD condition caused a higher (P < 0.05) erythrocyte osmotic fragility at 0.5 %, 0.3 % and 0.1 % NaCl concentration. The final live body weight (1,344.0 ± 54.22 g) and weight gain (1,120.0 ± 52.48 g/chick) of quercetin-treated HSD was significantly higher (P < 0.05) when compared with the final live body weight (1,071.0 ± 60.76 g) and weight gain (842.50 ± 57.07 g/chick) of the quercetin-treated LSD group. The feed conversion ratio was significantly lower in the quercetin-treated HSD group (1.43 ± 0.07) when compared with untreated HSD (1.79 ± 0.10), LSD (2.20 ± 0.10) and quercetin-treated LSD (2.10 ± 0.12) groups. A higher viability ratio was recorded in the quercetin-treated groups. Quercetin administration had a weight-enhancing effect, correlated directly with the increasing age of broiler chicks in quercetin-treated HSD (r = 0.950; P < 0.01) and quercetin-treated LSD (r = 0.968; P < 0.01) groups. Low stocking density condition and quercetin administration enhanced meat quality by preventing early rise in pH. This is beneficial to consumers that may wish to refrigerate meat for future consumption. The results suggest that quercetin was most beneficial in conditions of discomfort and, may, be useful as a supplement in broiler chicken production, especially in stress due to HSD. It was concluded that the administration of quercetin at 50 mg/kg body weight enhanced performance through efficient feed utilisation, alleviated stocking density-induced social and physiological stress and prolonged the shelf-life of stored broiler breast meats.

EFFECTS OF QUERCETIN ON SOME PHYSIOLOGICAL PARAMETERS AND PERFORMANCE OF BROILER CHICKENS RAISED AT DIFFERENT STOCKING DENSITIES

EFFECTS OF MELATONIN ON NEURO AND REPRODUCTIVE TOXICITY INDUCED BY IN UTERO AND LACTATIONAL CO-EXPOSURE TO CHLORPYRIFOS AND CYPERMETHRIN IN MALE WISTAR RATS

ABSTRACT

Organophosphates and pyrethroids are common insecticides used in combination. Their use in agricultural and indoor activities has opened several windows of exposure to vulnerable non-target young animals and humans during pregnancy and breast-feeding, which may adversely affect their physical, reproductive and mental health. Oxidative stress has been implicated in pesticide-induced toxicity.

The aim of the study was to investigate the ameliorative potentials of melatonin (MEL) on neurotoxic and reproductive changes provoked by in utero and lactational co-exposure to chlorpyrifos (CPF) and cypermethrin (CYP) in male Wistar rats. Sixty out of the sixty five pregnant rats obtained following overnight mating of seventy-two sexually-mature female nulliparous Wistar rats with 72 adult males in a 1 : 1 mating scheme were used for the study.

Evidence of mating was assessed in each female animal by the presence of spermatozoa deposit or vaginal plug. Day 1 of gestation was the day copulation plugs/spermatozoa were found in the vagina. The 60 pregnant dams were thereafter divided at random into six 6 groups of 10 animals each. Group I (DW) was given distilled water (2 ml/kg), while group II (S/oil) was given Soya oil only (2 ml/kg). Group III (MEL) was dosed melatonin (0.5 mg/kg) only, while group IV (CC) was co-administered with CPF (1.9 mg/kg; 1/50th of the LD50) and CYP (7.5 mg/kg; 1/50th of the LD50); group V (MCC) was pretreated with MEL (0.5 mg/kg) and then co-exposed to CPF (1.9 mg/kg; 1/50th of the LD50) and CYP (7.5 mg/kg; 1/50th of the LD50), respectively, 30 minutes later.

Group VI (CCM) was co-exposed to CPF (1.9 mg/kg; 1/50th of the LD50) and CYP (7.5 mg/kg; 1/50th of the LD50) respectively, and post-treated with MEL (0.5 mg/kg), 30 minutes later. The regimens were given to the dams by gavages once daily from gestation day 1 (GD 1) to postnatal day (PND) 21.

Weekly monitoring of body weight and clinical signs on the dam were carried out and recorded. The dams were allowed to deliver normally and some developmental/ reproductive/neurobehavioural parameters were evaluated on the FI generation male rats at different time intervals, namely: litter size and weight, number of lives and dead pups, anogenital distance (AGD), crown-rump length (CRL), time of eye and ear opening, time of testicular descent, surface and aerial righting reflex, ability to walk and time pivoting, negative geotaxis, inclined plane, ladder walk, bean walk, excitability score, forepaw grip, forced swimming and cognitive (learning and short-term memory) tests.

At PND 80, F1 male rats were mated to a sexually-matured, untreated nulliparous female in a 1 : 1 mating schedule and the females were observed for reproductive indices, including mating index, live-birth index, sex ratio, viability index, gestational length index, fertility index, pregnancy (gestation) index. At the end of the experiment, the rats were sacrificed by jugular venesection after light chloroform anaesthesia.

The F1 male rats were evaluated for epididymal sperm concentration, sperm motility, sperm live-dead ratio, sperm morphology, and concentrations of sex [follicle stimulating hormone (FSH), luteinising hormone (LH) and testosterone] and thyroid [triodothyronine (T3), thyroxine (T4) and thyroid-stimulating hormones (TSH)] hormones, and tissues‟ biochemical parameters (levels of malondialdehyde [MDA] concentration; activities of superoxide dismutase [SOD], catalase [CAT], glutathione peroxidase [GPx] and acetylcholinesterase [AChE], concentration of testicular and epididymal total and free sialic acid, and epididymal fructose).

Post-mortem gross and histopathological examinations of some tissues of rats were also conducted on F1 generation male rats. The results revealed alterations in litter size and weight, number of live/dead pups, anogenital distance (AGD), crown-rump length (CRL), time of eye and ear openings, time of testicular descent, surface and aerial righting reflex, ability to walk and time pivoting, negative geotaxis, inclined plane, ladder walk, beam walk, excitability score, fore-paw grip time, forced swimming and cognition; in the group co-exposed to CPF and CPY.

Mating of F1 generation male rats of dams co-exposed to CPF and CPY with untreated female rats showed alteration in mating index, live birth index, sex ratio, viability index, gestational length index, fertility index, pregnancy (gestation) index.

The F1 male rats of CC group showed decreased epididymal sperm concentration, sperm motility; sperm live-dead ratio, concentrations of sex hormones levels (FSH, LH, and testosterone) and altered sperm morphology. Similarly, there were alterations in the tissue levels of MDA, thyroid hormones (T3, T4 and TSH), testicular and epididymal total and free sialic acid, epididymal fructose, SOD, CAT, GPx and AChE in the F1 male rats.

Pre-and post-exposure treatment with MEL mitigated the pesticide-evoked developmental, reproductive, reflexogenic, neurobehavioural, biochemical, oxidative and histological changes in F1 male rats. However, MEL pretreatment was more beneficial than post-exposure treatment. The mitigation of pesticide-evoked developmental, reproductive, reflexogenic, neurobehavioural, biochemical, oxidative and histological changes by MEL was partly due to its antioxidant and free radical scavenging properties.

EFFECTS OF MELATONIN ON NEURO AND REPRODUCTIVE TOXICITY INDUCED BY IN UTERO AND LACTATIONAL CO-EXPOSURE TO CHLORPYRIFOS AND CYPERMETHRIN IN MALE WISTAR RATS

EPIDEMIOLOGY OF NEWCASTLE DISEASE IN VILLAGE CHICKENS IN BAUCHI STATE, NIGERIA

ABSTRACT

Newcastle disease (ND) is considered as a major constraint to village chicken production in Africa. A study on the epidemiology of ND in village chickens was conducted in nine communities randomly drawn from nine Local Government Areas (LGAs) in Bauchi State to asses: the importance of NDto village chicken farmers using the participatory epidemiological tools; the prevalence of ND from monthly disease reports, the prevalence of ND virus (NDV) and seroprevalence of ND; andacceptance among farmers of ND vaccination and its benefits.

A sixty Monthly Disease Reports (June 2010-May 2015) submitted by the eight Area Veterinary Offices covering the studied communities were examined at the office of the Director Veterinary Services Bauchi State for cases of ND disease in poultry. Staff from the Veterinary Department was assigned the duty of inviting farmers in each community for a focus group discussion (FGD) to assessthe importance of ND among the common diseases of village chickens in their community.

Participants of FGDs also selected eight households (HHs) in each community. From these HHs samples of blood and cloacal swabs for detection and determination of prevalence of antibodies and antigen of ND virus (NDV) were collected; chickens were vaccinated against ND to assess acceptance and benefit of vaccination. Also, volunteering members from these HHs answered questionnaire on village chicken management. Haemagglutination inhibition test (HIT) was used to detect ND antibodies from sera extracted from the blood collected from village chickens. Conventional Reverse Transcriptase Polymerase Chain Reaction was used to detect NDV.

Cloacal swabs that tested positive for ND were inoculated into 9-11 day old embryonate chicken eggs to isolate NDV. The prevalence of reported cases of ND in poultry was 11.6%. Newcastle disease was mostly reported during the cold season (October-March) with the highest seasonal index of 44.4% and an odds ratio of 6.6 in November. The proportional piling scores for ND in Chinade was 146/249 (69.9%), in Jalam 35/105 (32.4%), in Udubo 183/261(70.1%), in KafinMadaki 149/244 (61.1%), in Gongoro 80/183 (43.7%), in Dass 175/270 (64.8%), in Kutaru 126/243 (50.8%) and in Toro 173/288 (60.1%).

The pair wise ranking score for ND in Chinade was 4/5, in Jalam 5/6, in Udubo 5/6, in KafinMadaki 6/7, in Gongoro 4/5, in Dass 3/4, in Kutaru 5/6 and in Toro 4/5. Most of the respondents 71 (98.6%) had experienced outbreak of ND in their flock within the last six months with greater than 50% mortality of 54 (75%) chicken during the cold season. Vaccination against ND was not practiced by any of the respondents. The seroprevalence of ND was 36.4%;and the prevalence of NDV was 29.9%.

Three isolates (3/20; 15%) were obtained from cloacal swabs of chickens from Toro. Vaccination against ND was first carried out on 1139 village chickens in 72 HHs and the second vaccination was carried out on 814 chickens in 54 of the 72 HHs. Rejection of vaccination was experienced in 8 HHs (8/72; 11.11%). Additional ND vaccines were given to 746 chickens in 64 HHs that were neighbours of the initial participants.

A proportional piling scores given by 68 participants was 100% (340/340 beans shared) for acceptance of vaccination against ND, while, a score of 92.7% (338/365 beans shared) was given in favour of ND vaccine being beneficial to farmers of village chickens. The study concludes that ND is an important disease of village chickens that is widespread and cannot be controlled by the current management practices. Vaccination of village chickens against ND was accepted and beneficial to farmers.

The study recommends characterization of local strains of NDV by National Veterinary Research Institute, Vom; prioritization of ND by Bauchi State for state wide immunization and routine vaccination of village chickens against ND by farmers for an improvement in village chicken production.

EPIDEMIOLOGY OF NEWCASTLE DISEASE IN VILLAGE CHICKENS IN BAUCHI STATE, NIGERIA

EFFECT OF MULTIPLE INFECTIOUS BURSAL DISEASE VACCINATION ON ANTIBODY RESPONSE OF PULLETS TO NEWCASTLE DISEASE VACCINE LASOTA AND PATHOLOGICAL CHANGES IN MAJOR IMMUNE ORGANS

ABSTRACT

This study was conducted with the aim of determining the effect of multiple infectious bursal disease vaccination on antibody response of pullets to Newcastle disease (ND) vaccine LaSota and pathological changes on major immune organs. A total of 120 day-old pullets were used, the birds were randomly divided into 6 groups (A, B, C, D, E and F), consisting of 20 chicks each. A freeze-dried live attenuated infectious bursal (IBD) disease vaccines, M.B. strain (ABIC) and Newcastle disease vaccine LaSota strain live virus (ABIC) were administered orally. Group A pullets were vaccinated with IBD vaccine at 1st and 2nd weeks of age. Group B pullets received IBD vaccine at 2nd and 4th weeks. Group C pullets received IBD vaccine at 3rd weeks. Group D pullets received IBD vaccine at 2nd, 4th and 6th weeks. All the groups with the exception of group F received ND vaccine at 3rd and 6th weeks. Group F pullets received no vaccine. Ten serum samples from each group in this experiment were collected for 8 weeks and tested against ND for antibodies using ELISA test. Mean Elisa ND antibody titre had indicated statistical difference at week 5, where groups B and A (P≤0.01), C and B (P≤0.01) and D and C (P≤0.05). At week 7 groups D and C (P≤0.01). The multiple IBD vaccine had negative effect on ND vaccine LaSota, group C had highest ND mean Ab titre of 11480.6 ±827.45 at week 8. The gross lesions observed were more severe in groups B and D and milder in group E and F. Histopathologically lesions were more severe in groups that where vaccinated with multiple IBD vaccines. From this work it was recommended that it is safer to give two weeks interval before repeating infectious bursal disease vaccination for Newcastle disease vaccine LaSota vaccination to be effective.

CHAPTER ONE

1.0 Introduction

1.1 Historical Background

Poultry diseases are significant restrain to the efficiency and profitability of poultry production. From a global perspective basically the same range of poultry pathogens are responsible for losses in livability, egg production, growth rate and feed efficiency worldwide (Shane, 2004). In many developing countries, velogenic Newcastle disease (ND) is endemic, and represents an important limiting factor in the development of commercial poultry production and the establishment of trade links (Alexander et al., 1997). The constant loses from ND severely affect the quality and quantity of food for people on marginal diets (Saif et al., 2005). The endemicity of ND in Nigeria leads to high environmental dissemination of the virus and this is enhanced by poor husbandry practice (Okwor and Eze, 2010). The outbreaks of ND were reported to be more common in layers than in broilers (Abdu et al., 2005).

1.2 Statement of research problem

In Nigeria, poultry contributes about 15% of the total annual protein intake with approximately 1.3 kg of poultry products consumed per head per annum (Ologbon and Ambali, 2012). However, major factors militating against the growth of the poultry industry include infectious diseases especially infectious bursal disease (IBD) and ND. Farmers administer ND and IBD vaccines simultaneously with the aim to reduce stress and minimize labour cost (Okwor et al., 2013). In Nigeria, farmers vaccinate birds against IBD and ND at regular intervals depending on the vaccination scheduled, some vaccinate against IBD once, twice and thrice (Okwor et al., 2013). Vaccination using live IBD vaccine has been reported to affect response of birds to vaccination against other disease like ND (Ali et al., 2004). However, some viruses like IBD virus are immunosuppressive in nature and may interfere with chicken’s immune responses to other viral vaccines which may be responsible for vaccination failure (Hair-Bejo et al., 2004). The use of live vaccines can result in negative vaccination reactions, especially if the birds are stressed (Alexander, 2004). Infectious bursal disease has been reported to be immunosuppressive and even the attenuated vaccines are reported to cause pathology in the bursa of Fabricius (Adamu et al., 2013). Several IBD vaccination failures have been reported in Nigeria (Abdu, 1986). The endemic nature of Newcastle disease in Nigeria ensures the ND virus is almost always present in poultry populations particularly village chickens and backyard flocks (Abdu, 1997). The village poultry flocks suffer from outbreaks of ND annually and these flocks are also in constant contact with backyard flocks. Vaccine failures in Nigeria were reported to occur primarily due to improper storage, transportation and administration of vaccine and secondarily due to interference with active immunization by Marternally derived antibody (Abdu, 1997). Research efforts on IBD control by conventional immunization or strict management practice is wroth with frustration.

1.3 Justification of the Study

Newcastle disease and infectious bursal disease have remained the two most important viral infectious diseases that are threatening commercial poultry production in most parts of the world (Agoha et al., 1992; Sonaiya et al., 1999; Permin and Pederson, 2002). The epidemiology of these two diseases involves host’s immune status, wide host range, thermo-stability and antigenic variations in strains of the causative viruses (El-Yuguda et al., 2014). Unfortunately, severe outbreaks of ND still occur with high mortality rates in vaccinated and unvaccinated flocks (Musa et al., 2010). Economic losses of IBD are incurred as a result of the high mortality rate and the predisposition to secondary infection (Adewuyi et al., 1989). Field IBDV reports by different researchers indicated varying level of maternally derived antibody (MDA) in birds (Giambrone, 1983). Neutralization of IBDV by MDA at the time of vaccination was also reported (Okoye, 1984; Abdu, 1997). Immunosuppression caused by IBD has a significant economic impact due to widespread nature of the virus in chicken (Abdu, 1997). The infection at an early age compromise the humoral and the cellular immune response of chicken (Abdu, 1997). It has been observed, that ND outbreak occur more commonly in flocks recovered from IBD (Adewuyi et al., 1989). Therefore, this work was designed to find out whether IBD vaccination will have an effect on the antibody response to Newcastle disease vaccine (LaSota) strain.

1.4 Aim

The aim of the research was to study the effects of multiple IBD vaccinations on antibody response of pullets to ND vaccine LaSota and pathological changes on major immune organs.

1.5 Objectives of the Study
Were to;

  1. Determine the antibody response of pullets to Newcastle disease LaSota vaccine following multiple IBD vaccine application in pullets.
  2. Observe the gross and histopathological changes of some immune organs of pullets after IBD vaccination.

1.6 Research Questions

  1. Does IBD vaccination affect antibody response of pullets to ND LaSota vaccine?
  2. Does IBD vaccination cause pathological changes in major immune organs of pullets?
EFFECT OF MULTIPLE INFECTIOUS BURSAL DISEASE VACCINATION ON ANTIBODY RESPONSE OF PULLETS TO NEWCASTLE DISEASE VACCINE LASOTA AND PATHOLOGICAL CHANGES IN MAJOR IMMUNE ORGANS

COMPARATIVE STUDIES ON THE INFECTIVITY AND PATHOGENICITY OF EXPERIMENTAL TRYPANOSOMA BRUCEI BRUCEI INFECTION IN MICE, RATS, RABBITS AND GUINEA FOWLS

ABSTRACTS

The study compared the infectivity and pathogenecity of experimental Trypanosoma brucei brucei infection in mice, rats, rabbits and guinea fowls. A total of 10 each of the following animals‟ mice, rats, rabbits and guinea fowls of both sexes were used for the study. Each group of the animal species was divided into two groups (infected and control) of five animals each. The mice, rats, rabbits and guinea fowls in the infected groups were individually inoculated with blood containing 1 x106 Trypanosoma brucei brucei (Fadere stock). All animals in the control groups were not infected. Patent parasitaemia as determined by haematocrit centrifugation technique was between 3-4 days in the mice and rats, while it was 7-8 days in rabbits. No parasitaemia was seen in the infected Guinea fowl throughout the study. The mean body weights of mice, rats and rabbits decreased in the infected group as compared to the control group. All animals in the infected group with the exception of guinea fowls showed increase in body temperature. In the mice and rats there were significance diferrences (SD) (p < 0.05) in the overall mean PCV, HGB and RBC between the infected groups (IG) as compared to the control group (CG). In the rabbits there were SSD (P < 0.05) in the overall mean PCV, HGB and RBC between the IG (36.1 ± 0.6%, 12.11 ± 0.8 g/dl and 5.9 ± 0.4×106) and CG (43.7 ± 0.5%, 14.1 ± 0.9 g/dl and 7.23 ± 0.3×106 respectively). There was no SD (P > 0.05) between the overall mean PCV, HGB and RBC of the infected guinea fowls and those of the control group throughout the period of the experiment. Also, no mortality was recorded among the infected guinea fowls as consequence of the infection. A decrease in mean total white blood cell (WBC) counts of the rats and the rabbits were observed while mice and guinea fowls groups showed no significance difference between the WBC of the infected and control groups. Microscopic lesions observed in the mice, rats and rabbits included congested central vein and perivascular cuffing, congestion and mononuclear cellular infilteration around blood vessels of the lungs, depletion of lymphoid cells, congested inter tubular spaces and focal necrosis of renal tubular epithelium. In the guinea fowls, the spleen revealed heamosiderosis. The study thus demonstrated that mice, rats and rabbits are, in order of susceptibility better laboratory models than the guinea fowls which tend to show some measure of resistance to Trypanosoma brucei brucei used in the experiment. Therefore rabbits could be use in our laboratory to preserve Trypanosoma brucei brucei.

CHAPTER ONE

INTRODUCTION

1.1 Background of the Study

Trypanosomosis is a disease of man, domestic (Fajinmi et al., 2011; WHO 2015) and wild animals (Abenga et al., 2006; Mbaya et al., 2009; 2011). It is transmitted by tsetse flies (Glossina spp.) and characterized by anaemia, oedema, cachexia, intermittent fever and death (Yakubu et al., 2014). In Africa including Asia and South America it is transmitted by several biting flies like Tabanus, Hippobosca, Stomoxys (WHO 2015; Yakubu et al., 2014).

The Trypanosoma species affecting man and his domestic animals have been subdivided into two groups, the haematic group (Trypanosoma congolense, T. vivax) which remain in the blood plasma and the tissue invading group (T. brucei brucei, T. brucei gambiense, T. brucei rhodesiense and T. equiperdum) that are found in extra and intra vascular spaces (Abubakar et al., 2005; Chretien and Smoak, 2005; Ngure et al., 2008). Because of their presence in the blood, these invading parasites produce numerous changes in the cellular and biochemical constituents of blood (Taiwo et al., 2003). Infection with Trypanosoma brucei infection like other Trypanosoma infection precipitate red blood cell destruction which results in anaemia as well as tissue damage (Ekanem and Yusuf, 2008; Akanji et al., 2009).

Clinically, the effects of trypanosomosis in animals range from anaemia, immunosuppression, depression with inability to rise, pyrexia directly associated with parasitaemia, paleness of mucous membrane, rapid pulse beat, retarded growth, roughness of haircoats. Reduced capacity to work leading to morbidity and mortality in the absence of treatment (Batista et al., 2012; Silva et al., 2013).

In addition are enlargement of peripheral lymph nodes, reduced milk production, low meat quality, and weight loss as well as reproductive disorders such as infertility, abortion, stillbirth.

COMPARATIVE STUDIES ON THE INFECTIVITY AND PATHOGENICITY OF EXPERIMENTAL TRYPANOSOMA BRUCEI BRUCEI INFECTION IN MICE, RATS, RABBITS AND GUINEA FOWLS

DETERMINATION OF AFLATOXIGENIC FUNGI IN POULTRY FEEDS AND AFLATOXIN B1 IN FRESH AND BOILED BROILER LIVERS IN LIVE BIRD MARKETS IN ZARIA, NIGERIA

ABSTRACT

There is increasing concern for the contamination of poultry products with Aspergillus strains responsible for aflatoxin production. The occurrence of aflatoxigenic fungi in poultry feeds and aflatoxin B1 in fresh and boiled broiler liver samples in live bird markets in Zaria, Nigeria were examined. Feed samples were cultured for fungi on Sabouraud dextrose chloramphenicol agar to detect the presence of Aspergillus species. Aflatoxin production potential was evaluated using Czypeck dox agar. Desiccated coconut agar was used to detect fluorescence of Aspergillus spp and indirect competitive enzyme linked immunosorbent assay (cELISA) was used to determine aflatoxin residue concentrations (µg/kg) in both fresh and boiled (100°C for 90 mins) liver samples. Out of the 300 poultry feed samples tested, 234(77.9%) were contaminated with Aspergillus spp of which 126(53.8%), 48(20.5%), 27(11.5%), 15(6.4%), 9(3.9%), 5(2.1%), 3(1.3%), and 1(0.4%) were identified as A. flavus, A. fumigatus, A. parasiticus, A. niger, A. nidulans, A. terreus, A. nomius, and A. caelatus respectively. On desiccated coconut agar, Aspergillus had isolation frequency of 98(51.9%) with (P < 0.05). Samples from Dan Magaji, had isolation frequency of 28(28.6%), Zaria City 21(21.4%), Samaru 17(17.4%), Sabon Gari, 7(7.1%), Kwangila 14(14.3%) and Tudun wada 11(11.2%). The mean and standard deviation of aflatoxins in freshly tested liver concentration were 41.45 ± 29.55, 66.40 ± 22.28, 9.90 ± 6.50, 10.00 ± 1.74, 29.80 ± 17.16 and 35.25 ± 8.14 µg/kg for Zaria city, Sabon Gari, Kwangila, Samaru, Tudun wada and Dan Magaji respectively. All the liver sample of birds in live bird markets had aflatoxin B1 concentration higher than the maximum limit (4 µg/kg) set by World Health Organization and Standard Organization of Nigeria. Also, there was statistically significant (P < 0.05) difference in sample locations. Furthermore, the mean value and standard deviation of boiled liver contents were 8.2 ± 5.0, 1.8 ± 0.7, 0.6 ± 0.3, 29.0 ± 9.5, 5.2 ± 5.1, 4.5 ± 3.3 µg/kg for Samaru, Kwangila, Dan Magaji, Sabon Gari, Zaria City and Tudun wada respectively. The mean value and standard deviation of liver content before and after boiling were 15.98±15.00 and 8.22±10.52 µg/kg respectively. There was no statistical difference in the processed form of liver (P < 0.05). Aflatoxin content, were found in edible tissues both before and after heat treatment. Strict measures should be taken to monitor toxins in feed and chicken meat products.

CHAPTER ONE

INTRODUCTION

1.1 Background of the Study

The study of mycotoxins really began in 1960 with the outbreak of Turkey X disease in the U.K, linked to peanut meal imported from Brazil (Sargeant et al., 1961). Mycotoxins, the secondary metabolites from toxigenic fungi, are contaminants in foods and feeds, exerting harmful effects upon animal and human health (Zahoor-ul-Hassan et al., 2010). Mycotoxins are low-molecular weight secondary metabolites, produced by certain strains of filamentous fungi, such as Aspergillus, Penicillium and Fusarium, which invade crops in the field. Mycotoxins are structurally-diverse simple C4 compounds, for example, moniliformin, to complex substances such as the phomopsins which are filamentous fungi that vary in their chemistry and biological effects (Sudakin, 2003; Dinis et al., 2007). The most important mycotoxins in naturally contaminated food and feeds are aflatoxins (AFs), ochratoxins (O), zearalenone (ZEN), T-2 toxin, deoxynivalenol and fumonisins (Sultana and Hanif, 2009). No region of the world escapes the problem of mycotoxins and according to Lawlor and Lynch (2005) and Okoli et al. (2006b), mycotoxins are estimated to cause loss of as much as 25 % of the world’s crops each year. The mycotoxins accumulate in foods during storage under favourable conditions of ambient temperature and relative humidity for fungal growth. Mycotoxins are produced only under aerobic conditions Ratcliff (2002), where they often attack ground nut, maize, cotton seed cake, wheat, and soyabean. They are regularly implicated in toxic syndromes in animals and humans (Charoenpornsook and Kavisarasai, 2006). However, animals may have varying susceptibilities to mycotoxins, depending on physiological, genetic and environmental factors. Most mycotoxins such as aflatoxin B1, T-2 toxin and ochratoxin A inhibit protein synthesis (Charoenpornsook and Kavisarasai, 2006). The consumption of multiple doses of mycotoxin-contaminated diet may induce haematological, biochemical, physiological changes in the liver and growth depression in animals (Awad et al., 2006; Shi et al., 2006; Rezar et al., 2007; Gowda et al., 2008). Thus, the presence of mycotoxins in poultry feeds can result in significant economic losses to the poultry industries (Awad et al., 2006). Mycotoxins have been detected in various food commodities from many parts of the world and are presently considered as some of the most dangerous contaminants of food and animal feeds (Okoli, 2005; Okoli et al., 2006a; 2006b; 2007a; 2007b). Adverse effects of mycotoxins on animal health and production have been recognized in animals kept under intensive management such as poultry, swine and cattle as a consequence of the consumption of high levels of contaminated cereals and oilseeds in the diet (Charoenpornsook and Kavisarasai, 2006).

Aflatoxins produced by the toxigenic fungi, mainly Aspergillus flavus and Aspergillus parasiticus, constitute one of the major health hazard groups of naturally-occurring toxicants, both for man and animals. There are six forms of aflatoxins: B1, B2, G1, and G2 are found in plant-based food, while M1 (metabolite of B1) and M2 are found in foods of animal origin. Aflatoxin B1 is the most harmful form due to its direct link to human liver cancer (Leslie et al., 2008; USAID, 2012). The order of potency for both acute and chronic toxicity of aflatoxins is AfB1 > AfG1 > AfB2 > AfG2 (Santacroce et al., 2008). Among the four major groups of aflatoxins; namely B1, B2, G1 and G2; aflatoxin B1 (AFB1) is the most toxic and it is a known carcinogen. Acute or chronic aflatoxicosis in domestic birds results in decreased meat/egg production, immunosuppression and hepatotoxicosis (Verma et al., 2004; Khan et al., 2010). Human exposure to aflatoxins may result from consumption of plant-derived foods that are contaminated with the toxins, and the carry-over of aflatoxins and their metabolites in animal products such as meat and eggs (CAST, 2003).

Aflatoxin is one of the numerous naturally-occurring mycotoxins that are found in soils and foods. Aflatoxins have been found in soil as well as in grains, nuts, dairy products, tea, spices and cocoa, as well as animal and fish feeds (Waliyar et al., 2008).

1.2 Statement of the Research Problem

Mycotoxins that occur in food and/or feedstuffs have great significance in the health of humans and livestock (Tola and Kebede, 2016). The growth of this heterologous group of fungi in feed and the generation of secondary metabolites of mycotoxins have adverse effects on the poultry industry and human health as well (Monson et al., 2015; Oliveira et al., 2015).

Exposure of Pregnant women to aflatoxin may cause increased maternal mortality and low birth weight. Infants exposed to aflatoxin-contaminated foods may be more susceptible to stunting growth and malnutrition (Shuaibu et al., 2010). Aflatoxins impair livestock growth, reproduction, immune functioning and ability to metabolize vaccines (Makun et al., 2012).

The economic impact of reduced animal productivity, increased incidence of disease due to immunosuppression, damage to vital organs and interference with reproductive capacity is many times greater than the impact caused by death due to mycotoxin poisoning (Akande et al., 2006). It has been pointed out that aflatoxin contamination of feeds of food-producing animals can result in residues of ingested aflatoxins or its metabolites in meat, milk and egg (Gizachew et al., 2016).

It has been estimated that more than 5 million people in developing countries world-wide are at risk of chronic exposure to aflatoxins through contaminated food (Shepard, 2005; Strosnider et al., 2006). Animals exposed to aflatoxins show a variety of symptoms, depending on the animal species. However, in all animals, aflatoxins may cause liver damage, decreased reproductive performance, reduced milk or egg production, embryonic death, teratogenicity, tumors and suppressed immune function, even when low levels are consumed (Akande et al., 2006). Aflatoxins are both acutely and chronically toxic in animals and humans (Pimpukdee et al., 2004).

Aflatoxin B1 is known to be the most toxic metabolite, especially in sensitive species such as poultry (Hussein and Brasel, 2001). Beside direct losses related to mortality, feed conversion and growth rate, recovering birds remain poor. Indeed, air sacculitis is a major reason for carcass condemnation at slaughter inspection (Kunkle, 2003; Lupo et al., 2010). It is proven that aflatoxin leads to reduced egg production as well as their quality in laying hens (Rizzi et al., 2003).

Poultry feeds in live bird markets is at risk of unsafe aflatoxin accumulation which can negatively affect human health, food security and economic trade (Williams et al., 2004). Their toxicity depends on different factors including its concentration, the duration of exposure, the species, sex, age, and health status of animals (Jewers, 1990).

DETERMINATION OF AFLATOXIGENIC FUNGI IN POULTRY FEEDS AND AFLATOXIN B1 IN FRESH AND BOILED BROILER LIVERS IN LIVE BIRD MARKETS IN ZARIA, NIGERIA

EFFECT OF MORINGA OLEIFERA LEAF SUPPLEMENTATION OF FEED ON PERFORMANCE, ANTIBODY RESPONSE, HAEMATOLOGICAL AND BIOCHEMICAL PARAMETERS IN BROILERS CHALLENGED WITH INFECTIOUS BURSAL DISEASE VIRUS

ABSTRACT

This study was conducted to determine the effect of dietary Moringa oleifera leaf (MOL) supplementation of feed on performance, antibody response, haematological and biochemical parameters of broilers challenged with a very virulent infectious bursal disease virus (vvIBDV). Fresh MOL was collected from Potiskum, Yobe State and air dried for five days, ground into powder using a milling machine and analyzed for nutrients and elements using standard method of the Association of Official Analytical Chemists. The phytochemical constituents analysis of MOL was done using the method described by Sofowora. Two hundred and forty day-old Ross 308 hybrid broiler chicks were randomly assigned into four groups (A, B, C and D) of 60 chicks each and raised in a deep litter house consisting of 4 separate compartments. All birds were fed with broiler starter (BS) from 0 to 28 days of age and broiler finisher (BF) from 29 to 49 days of age. Broiler starter (22% crude protein CP) and BF (20% CP) mash were formulated each with 5% MOL included as part of the feed ingredient for broilers in groups A and B while BS and BF for broilers in groups C and D were formulated without MOL. Only birds in groups A and C were vaccinated intramuscularly with 0.5 ml of an inactivated intermediate strain infectious bursal disease (IBD) vaccine at 14 and 21 days of age. Inactivated Newcastle disease virus (NDV) vaccine (Komorov strain) was also administered (0.5 ml) intramuscularly at 18 days of age to groups A and C. Birds in groups A, B and C were challenged intraocularly at 35 days of age with vvIBDV while those in group D served as control. Daily feed intake (DFI), average daily weight gain (ADWG), feed conversion ratio (FCR) and selling price (SP) per bird were determined for each group. Five birds were randomly selected and euthanized from each group on 35, 38 and 42 days of age and the bursa of Fabricius, thymus, spleen and Harderian glands were removed for evaluation of organ body weight index. Blood was collected from ten broilers in each group via the wing vein on 14, 21, 35, 38 and 42 days of age to determine the IBD antibody titre level, haematological and biochemical parameters. At 49 days of age, five birds from each group were slaughtered and their carcasses weighed to assess the performance of birds fed with MOL supplemented diets. The results of the nutrients analysis showed that MOL contained carbohydrate (55.14%), CP (25.9%), crude fibre (13.91%), moisture (7.94%), fat (5.85%), ash (3.72%) and energy (2930.63 Kcal/Kg). The phytochemical analysis of MOL revealed phytates (2.57%), tannins (2.19%), saponins (1.06%), oxalates (0.45%) and cyanides (0.1%). The elemental analysis on MOL revealed Ca (2.26%), P (0.35%), Mg (0.45%), K (1.9%), Na (0.11%), Zn (34 ppm), Cu (7.5 ppm), Mn (40.5 ppm), Fe (116.5 ppm) and Se (0.85 ppm). Broilers in group D correlated more strongly (Pearson correlation = 0.921; P = 0.000) in their feed intake than those in groups B (Pearson correlation = 0.875; P = 0.000), C (Pearson correlation = 0.863; P = 0.000) and A (Pearson correlation = 0.862; P = 0.000). Broilers in groups A and B had weaker correlation (Pearson 0.379 108; P = 0.273). Broilers from groups D, A and B had a higher selling price/bird (N 1,151 ± 82.82, N1,093 ± 54.11 and N935.9 ± 70.69, respectively) than those in group C (N908.3 ± 63.97). There was an increase in the enzyme linked immunosorbent assay (ELISA) IBD antibody titre level of broilers between 21 and 35 days of age in groups A (1,379.89 ± 829.98 to 2,836.83 ± 463.58), C (1,576.94 ± 566.51 to 3,290.51 ± 848.87) and D (1,542.43 ± 106.80 to 2,953.49 ± 561.88), and up to 42 days of age in broilers of group B (1,205.94 ± 612.32 to 3,193.10 ± 478.52). Moringa oleifera leaf feed supplementation improved bursa (1.4, 1.4), spleen (1.3, 1.1) and Harderian gland (2.0, 2.0) organ to body weight index of broilers of groups A and B. Feeding broilers with 5% MOL supplemented diet without vaccination (group B) did not prevent vvIBDV from causing a decrease in lymphocyte count from 3.87 ± 1.52 to 2.67 ± 1.26 on day 3 pi. Supplementation of broiler feed with 5% MOL and vaccination with inactivated IBD vaccine did not prevent a decrease in PCV (28.60 ± 1.77 % to 21.80 ± 3.46 % and 25.22 ± 2.28 % to 21.44 ± 1.33 %) and RBC (2.44 ± 0.44 x 1012/L to 2.01 ± 0.42 x 1012/L and 2.25 ± 0.26 x 1012/L to 1.79 ± 0.52 x 1012/L), but caused an increase in Hb (10.55 ± 2.21 g/dl to 10.78 ± 1.95 g/dl and 9.81 ± 0.97 g/dl to 11.39 ± 1.17 g/dl) concentration on day 3 pi with vvIBDV in groups A and C. There were respective increase in aspartate aminotransferase and alanine aminotransferase levels in groups A (39.90 ± 3.96 IU L-1 to 45.10 ± 5.70 IU L-1and 42.90 ± 3.21 IU L-1 to 49.60 ± 3.56 IU L-1), B (39.80 ± 3.68 IU L-1 to 48.50 ± 4.22 IU L-1 and 43.30 ± 3.83 IU L-1 to 54.20 ± 5.53 IU L-1) and C (38.40 ± 3.20 IU L-1 to 42.80 ± 4.02 IU L-1 and 42.70 ± 4.80 IU L-1 to 48.60 ± 4.45 IU L-1). However, similar increase were observed in group D following challenge with vvIBDV (41.80 ± 3.85 IU L-1 to 45.30 ± 5.64 IU L-1 and 44.20 ± 4.52 IU L-1 to 51.60 ± 3.69 IU L-1). Supplementing broilers feed with MOL without vaccination against vvIBDV could not prevent lipid peroxidation (from 1.37 ± 0.23 IU-1 to 1.51 ± 0.30 IU-1) in broilers of group B following inoculation with vvIBDV. Supplementing broilers feed with MOL maintained the level of Na+ concentration in broilers of group A (140.00 ± 2.79 mg/dl to 139.90 ± 2.69 mg/dl) and B (140.10 ± 2.51 mg/dl to 138.30 ± 2.50 mg/dl) following inoculation with vvIBDV. Feed millers are encouraged to create awareness among poultry farmers on the nutritional and health benefits of MOL inclusion in the diets of broilers. Broilers fed with MOL supplemented diets can be vaccinated by farmers since it has no adverse effect against immune response to IBD.

CHAPTER ONE

INTRODUCTION

1.1 Background Information

EFFECT OF MORINGA OLEIFERA LEAF SUPPLEMENTATION OF FEED ON PERFORMANCE, ANTIBODY RESPONSE, HAEMATOLOGICAL AND BIOCHEMICAL PARAMETERS IN BROILERS CHALLENGED WITH INFECTIOUS BURSAL DISEASE VIRUS