Epidemiology and Aspects of Economic Studies on Bovine Fasciolosis in Adamawa State, Nigeria

Abstract

Cross sectional epidemiologic studies, and aspect of economic assessment of bovine Fasciolosis was conducted in Adamawa state abattoirs (Yola, Mubi and Numan) using postmortem examination of liver of slaughtered animals and the ELISA screening for fasciola antibodies.. The objectives of the study were; to determine the prevalence rate of Fasciola infection using both conventional detection of flukes and the ELISA screening method; to assess seasonal trend as well as age, sex and breed distribution of infection; evaluate magnitude of liver condemnation and assess the economic losses arising therefore. Based on the average slaughter size, two visits per week at Yola abattoir and once each to Mubi and Numan were made for one calendar year. A total of 3015 cattle were slaughtered and examined and 657 liver fluke cases were recorded; this give a prevalence rate of 21.8%. The prevalence rate at Yola, Mubi and Numan were 22.08%, 22.34% and 19.92% respectively. Of the total slaughter, 1490 (49.42%) were slaughtered at Yola abattoir, 998 (33.10%) at Mubi and 527 (14.94%) Numan. One thousand and seventeen (33.73%) of the slaughtered cattle were males and 1998 (66.27%) were females. For the state, the overall sex-specific prevalence rate was significantly higher (P<0.05) in females (23.6%) than in males (18.2%). Age-specific prevalence rate is highest (23.3%) in the groups that are 49-72 months. Statistical analysis showed no significant difference in prevalence rate among the age groups; there is no association between infection rate and age. The breeds slaughtered in all the abattoirs comprised of 1037(34.39%) Red Bororo, 794 (26.33%) Adamawa gudali, 689 (22.85%) White Fulani, and 495 (16.42%) Sokoto Gudali. The breed-specific prevalence rate was lowest 61(12.32%) in Sokoto Gudali and highest 325(31.34%) in Red Bororo. Chi-square analysis indicated that there was strong asssociation between infection and breeds. A total of 1405(46.60%) were slaughtered during the dry season and 1610(53.40%) during the wet season. There was a highly significant difference in infection prevalence between the seasons (P<0.05). There was a significant difference (P<0.05) between the number of fasciolosis cases that occurred in the dry season (25.98%) and that of the wet season (18.14%). In conclusion there was strong association (P<0.05) between season, sex, breeds of the cattle and the disease. For the ELISA Screening method, all the 60 sera samples that were confirmed positive at postmortem were also positive of ELISA (100%), 11 (8.33%) of the 60 negative were positive. For ante-mortem 9 (15%) of the 60 animals tested at lairage and 23 (38.37%) of the 60 animals at the breeding herds were also positive to ELISA.The sensitivity of the ELISA Kit was 81.7% and the specificity is 100%.The kit was found very effective in detection of fasciola infection in live animals. The total economic loss encountered due to condemnation of infected liver or proportional to the level of infection for one year in this study was more than ten million Naira per annum. It was observed that bovine fasciolosis is an obstacle to livestock production and development in Adamawa state and Nigeria. Lack of vaccine production and use against fasciolosis has led to use of the available drug for treatment. Policies on the importation, sales and utilization of veterinary drugs should be carefully controlled. There is a need by Veterinary profession to control this chronic parasitic disease whose prevalence rate is on the rise in Adamawa state. Although not yet documented in Nigeria,. human fasciolosis is now recognised as an emerging zoonosis by the World Health Organisation (WHO). Research on the presence and significance of the disease in humans is advocated in Adamawa state and the whole Nigeria.