Evaluation of Factors Limiting Turkey Production in Enugu State And Comparison of Pathology Associated With Newcastle Disease in Turkeys And Chicken

Abstract

The objectives of this study were to evaluate the factors limiting turkey production in Enugu State, Nigeria, determine the seroprevalence of Newcastle disease (ND) virus infection in turkeys raised in Enugu State and compare the clinical signs and lesions of velogenic ND virus (NDV) in turkeys and chickens. The study consisted of a cross-sectional survey of turkey producers in the three senatorial zones of Enugu State and experimental infection of chickens and turkeys with a velogenic NDV (VNDV). Three Local Government Areas in each of the three senatorial zones, Enugu East, West and North was purposively selected for the survey because of the preponderance of turkeys in the selected areas. A structured questionnaire was used for data collection. Two hundred and fifty copies of the questionnaire were administered to turkey producers in the selected areas. Five hundred and sixty-nine serum samples were randomly collected from unvaccinated turkeys in ninety backyard poultry farms in Enugu East, Enugu West and Enugu North senatorial zones. The sera were analysed for ND antibody titres using haemagglutination inhibition (HI) test. For the challenge experiment, 120 turkeys and 120 chickens were used. The 120 turkeys and chickens were divided into two groups of sixty vaccinated and sixty unvaccinated. The vaccinated groups were given HB1 (I/O) and La Sota ND vaccines on day 1 and day 21 of age respectively. Inoculated birds were given 0.2 ml (10 6.46 per ml) of the VNDV (KUDU 113) intramuscularly, at 6 weeks of age. Morbidity and mortality, changes in live body weight and gross lesions were recorded. Antibody response of the birds were carried out by collection of sera 12 on days 0, 5, 10, 15 and 21 PI. Pack cell volume (PCV), haemoglobin concentration (HbC), red blood cell count (RBC) and white blood cell (WBC, total and differential) were carried out on days 0, 3, 6, 10, 15 and 21 PI. Data generated from survey were subjected to descriptive statistics and Chi-square test, while for the challenge studies, students’ t test and one way analysis of variance were used. Variant means were analyzed post hoc using the least significant difference method. Significance was accepted at p < 0.05. Turkey production was carried out mainly by adult female in Enugu East (65.3%) and Enugu West (57.7%) and adult males in Enugu North (51.1%) Although most (87.5%) of the respondents in the three senatorial zones had formal education, they were not (48.8%) experienced in turkey production. The major (52.5%) age group involved in the business was 36- 50 years old. Turkey production in Enugu State was generally a part-time occupation as respondents were engaged in other primary occupation such as crop farming, trading, civil service etc. The management system adopted by the respondents in the three senatorial zones, Enugu East, Enugu West and Enugu North respectively were mainly (20.4%,55.0%,47.3%) intensive or semi-intensive (59.2%,34.0%,36.8%). Majority (84.8%) of the respondents in Enugu State keep turkeys in small numbers (1-20) along with local chicken, exotic chicken, guinea fowl, ducks etc. According to majority (91.2%) of the respondent, turkey production was found to be profitable venture based on the cash generated after sale of the turkeys. Newcastle Disease (57.0%), fowl pox (65.0%), fowl typhoid (6.0%), fowl cholera (3.7%), ectoparasitism (1.0%), fracture and nutritional deficiencies (2.6%) were the diseases constantly encountered in turkey production by majority of the respondents and of all the diseases reported by the respondents, fowl pox (65%) and Newcastle Disease (57%) were the major diseases limiting production in the study area. The major factors limiting turkey production in Enugu State as identified by the respondents in the study area were high cost of feed (86.5%), high disease morbidity and mortality (85.2%), inadequate access to veterinary care (78.80%), unavailability and high cost of poults (74.40%), lack of management skills (63.3%) and lack of capital (61.7%) while minor problems were low reproductive potential (56.9%), theft and predators (52.5%). Out of the 569 sera collected from the three senatorial zones and tested for Newcastle Disease virus antibody, a total of 186 sera representing 32.7% were positive for Newcastle Disease antibody. Out of the 186 sera, 138 (74.1%) had titres of 8 and above and were considered protected while 48 (25.9%) had titres of less than 8 and considered to be at risk. The mean HI antibody titre in Enugu East senatorial zone against ND was significantly (P