A Retrospective Study of Poultry Diseases Diagnosed at the Veterinary Laboratory, Pokhara, Nepal

Abstract

A retrospective study of clinical case records of poultry diseases presented to the pathology unit of Veterinary Laboratory (VL), Pokhara was conducted for duration of one year (March 2018 to February 2019). The basis of diagnosis were necropsies, rapid diagnostic test (RDT), plate agglutination test (PAT), microscopic examination, ELISA and PCR. The diagnosed diseases were bacterial including colibacilosis, omphalitis, salmonellosis, chronic respiratory disease (CRD) and complicated chronic respiratory disease (CCRD); parasitic including coccidiosis, tapeworm and ascariasis; viral including new castle disease (ND), infectious bronchitis (IB), infectious bursal disease (IBD), Marek's disease (MD) and avian influenza (AI) and non-infectious diseases/disorders including immu-nosuppression, mycotoxicity (MT), enteritis, pneumonitis, ascites, dehydration, nephritis, hepatitis, gout, sudden death syndrome (SDS), paralysis, fatty liver syndrome (FLS), hydro pericardial syndrome (HPS) and necrotic enteritis (NE). Out of total 5,037 cases recorded, bacterial diseases accounted for 41.16%, followed by parasitic (22.67%), non-infectious (19.93%) and 16.24% viral. Coliba-cilosis (14.49%), IBD (12.67%) and coccidiosis (22.63%) were the most prevalent diseases in their respective category. The highest prevalence of overall diseases were found in the spring season (27.24%), followed by winter (26.70%), summer (23.94%) and autumn (22.12%). Out of 2,024 caecal scrapings taken from the chicken of more than two weeks of age and tasted for caecal coccidian oocyst, 583 (28.8%) were found positive. The prevalence of coccidiosis was found more in humid spring season (28.3%), followed by rainy (26.9%), autumn (24.4%) and winter (20.4%). On the rapid PAT of morbid chickens, 46.84% Salmonella and 56.51% Mycoplasma were found sero-positive. Similarly, 62.97% IBD, 42.02% ND and 9.5% AI were positive for their specific antigens on RDT. Majority of the cases were found related to poor management and bio-security measures of farm. Therefore, knowledge on seasonal occurrence of different diseases, their preventive measures as well as accurate diagnosis and treatment are the key factors for successful poultry farming.