최근 5년간 뉴캣슬병에 대한 전국적인 항체 양성율 변화

Nationwide seroprevalence of Newcastle disease for recent 5 years in Korea

Newcastle disease (ND) is a highly contagious disease of poultry that can cause severe economic losses throughout the world. Currently, nationwide ND sero-monitoring plan has been implemented to evaluate the immunity level of poultry in Korea. Present study was performed to analyze the trend of regional and annual ND seroprevalence in poultry. The results obtained were summarized as follows. The average seropositivity to ND virus was 81.8% by HI test and 75.6% by ELISA in 2002. And, it was increased in 2003 as high as 86.0% and 80.1%, respectively. It was worthy to note that the seropositivity in layers was more than 98% from 2004 to 2006. However, it was revealed as less than 80% in the broilers with regional differences during the same periods. Most of layer flock (98.2%) had the HI titer of more than 3 log2 in 2006. The percentage with higher than 7 log2 of the HI titer was 51.5% under 16 weeks of age. However, it was dramatically increased to 88.0% over 20 weeks of age.