EFFECTS OF NEOPLASTIC DISEASE VIRUSES ON THE PRODUCTION PERFORMANCE OF COMMERCIAL LAYER CHICKEN

Abstract

The economically important neoplastic diseases of poultry are Marek's disease, which is caused by a herpesvirus, and the Avian Leukosis, which is caused by retroviruses. In this study the aim was to determine the effects of the neoplastic diseases on the production performance in commercial layer chicken which has a significant effect in context of Bangladesh. Marek’s disease spread horizontally but Avian Leukosis transmit both horizontally and vertically. These diseases cause economic loss due to increased mortality and depressed performance. The prevalence of neoplastic disease was 46.03 % and 47.25 % in the flocks. Reduction of production percentage upto 13 %. Birds which were suffering from neoplastic problems found to observe depression, reduction of feed and water intake and reduced body weight. After post-mortem examination enlargement of liver, spleen, kidneys and other visceral organs was observed. Diffuse lymphomatous involvement of visceral organs such as the liver, spleen, ovary, kidney, heart and proventriculus was also seen. Marek’s disease can be protected by the vaccination program but Avian Leukosis is done by virus eradication program.