Prevalence, Diagnostic Methods, and Interpretation of Newcastle Disease Laboratory According to The Expert Opinion of Laboratory Experts in Iran

Newcastle disease is one of the most important diseases and challenges of the poultry industry in Iran. The diagnosis is based on clinical signs, necropsy, laboratory examination (virus isolation, serological tests and molecular techniques). The aim of this study was to evaluate the diagnostic methods and the interpretation of Newcastle disease laboratory tests and Newcastle disease prevalence among referrals laboratories samples. The cross-sectional study was conducted based on expert opinion in 2014. Data were collected by designing a questionnaire based on expert opinion. For qualitative variables, relative frequency and for quantitative variables mean 955 CI was calculated. The Chi square test was used to examine the significance of the studied variables. p < 0.05 was considered statistically significant. In 80% of cases, the diagnostic criteria are a serological test within two weeks interval. Only 23% of the laboratories use molecular techniques. 87% of cases prefer HI test to ELISA. In 58.6% of laboratories, they use 4 HA unit antigen for HI. Most experts consider titer 6 and above for broilers, 8 and above for Layers and 9 and above for Breeders as suspect titer. In 2013, 44% of referral cases for multi-casal respiratory disease were Newcastle, and 40% of referral cases for Newcastle, was Newcastle disease. In cases that there is no enough data from the field, experts opinion provide valuable data for the initial assessment of the disease status, diagnostic procedures, risk assessment.