Prevalence of salmonellosis among chicken brought for postmortem examination at the necropsy unit of the College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University
Abstract
The global poultry industry has more than 23 billion birds, among which is chicken whose total population in Uganda is estimated at about 47.6 million, contributing about 4.3 % of the annual agricultural revenue. Avian salmonellosis is one of the under reported and often misdiagnosed infectious disease that has great devastating effects on the poultry business in Uganda due to its high morbidity and mortality. A cross sectional prospective study was conducted on 114 birds to determine the gross manifestation and prevalence of salmonellosis in chicken submitted for disease diagnosis at Veterinary Necropsy Unit, College of Veterinary Medicine, Animal Resources and Biosecurity (COVAB) Makerere University. Necropsy was done on the chickens presented and gross lesions suggestive for salmonellosis were described, tissue samples from salmonella suspected cases were collected and submitted for bacteriology. Questionnaire was administered to consented farmers to assess the risk factors associated with the disease and data was collected using an excel-linked google form. The major lesions suggestive of salmonellosis were: white-greyish spots on the liver surface, haemorrhages on the kidney surface and spleen and enlargement of the liver. At necropsy 26.32%, (30/114) birds were suspected to have salmonellosis, and majority of the cases were from farmers that had a flock size ranging between 1000-5000 birds. On further laboratory analysis and culture, 5 (4.39%, 5/114) birds were confirmed to have salmonellosis, hence the prevalence of salmonellosis as per this study was 4.39% (5/114). It was observed that amongst the farms with positive salmonella cases, majority 80% (4/5) had layer flock and were kept on a deep litter system, 60% (3/5) of the farmers obtained their stock from local breeders. This study showed that there was a low prevalence (4.39%) of salmonellosis among chicken submitted for disease diagnosis at the Veterinary postmortem unit of Makerere University. Therefore, bacterial culture, isolation and identification should always be embarrassed as away of accurate diagnosis of salmonellosis cases.