PREVALENCE OF NEWCASTLE DISEASE IN WINTER SEASON IN CHITTAGONG AND EFFICACY OF CHALLENGE VACCINE AGAINST NEWCASTLE DISEASE

Abstract

A study was undertaken to determine the prevalence of Newcastle disease in poultry farms of Chittagong region during the month of January and February, 2012. In this period the efficacy of challenge vaccine against Newcastle disease was determined. Disease diagnosis was conducted on the basis of history, clinical findings and post-mortem lesions. And challenge vaccine efficacy was determined on the basis of laboratory test (HI test before and after vaccination) and field trials. Birds taken from 52 broiler farms and 15 layer farms were examined during the study (mortality before and after vaccination). Prevalence of Newcastle disease was (8.96%). Due to vaccination with ND killed, (Lasota) at initial stage of infection the mortality rate reduces to zero and HI titre of the broiler farms increases as follows 5.4 to 7.55, 4.6 to 7.25, 4.65 to 7.70 and in the layer farms as follows 4.56 to 7.13, 5.0 to 7.81, 4.93 to 8.13. The HI titre level were insignificant in difference (P>0.05) among the farms in case of both before and after vaccination. For HI test 60 blood samples (20 from each of 3 broiler farms) and 48 eggs (16 from each of 3 layer farms) were collected and tests were performed.