This study was conducted to detect the presence of avian pneumovirus (APV) antibodies in commercial poultry farms using Enzyme-linked immunosorbent assay (ELISA) and virus neutralization test (VN). Eighty seven chicken serum samples were collected from several commercial poultry farms in Al-Qassium area, Saudi Arabia during 2007-2008. The serum samples were collected from birds of various ages (from one-day old to 62 weeks of age). Antibodies to APV were detected in 50% (8 out of 16) by both ELISA and virus neutralization (VN) test at farms in birds of 11-18 weeks of age only. The total positive samples were 8/87 (9.2%) of all examined samples. In conclusion, this study indicated the presence of antibodies to APV among 11-18 weeks old commercial chicken at farms in Saudi Arabia.

Key words: Avian pneumovirus, Chickens, ELISA, Saudi Arabia, Virus neutralization test