An outbreak of sheep pox in an organized farm of Tamil Nadu, India

Abstract

Outbreak of sheep pox was noticed in flocks of Khilakaraisal in an organized government farm of Tirunelveli district during 2013. Mortality and morbidity rates were 4.17% and 80.00%, respectively. Both the sexes of sheep between 6 months to 2 years old were affected. DNA extracted from the scab specimens (n=5) were amplified using Capri pox specific p32 gene primers and yielded 192 bp product. In order to differentiate between sheep pox and goat pox PCR – RFLP was carried out. Digestion of PCR product with EcoRI enzyme yielded two fragments with a size of 123 bp and 63 bp which confirmed the presence of sheep pox virus. Histopathological examination of tissues revealed extensive hydropic degeneration of proliferating epidermal cells with presence of large number of intracytoplasmic eosinophilic inclusion bodies in the keratinocytes of epidermal cells in skin. Lung revealed large infiltration of lymphocytes and macrophages with presence of intracytoplasmic eosinophilic inclusions in the macrophages, proliferation of type II pneumocytes were prominent along with bronchiolar epithelial hyperplasia. The outbreak was controlled by effective preventive measures like vaccination of healthy animals, affected animals were treated with a course of antibiotic for 7 days, contaminated areas were disinfected and restricted the movement of animals from unaffected areas to infected areas.