INDOOR AIR QUALITY OF COMMERCIAL BROILER FARMS AFFECTING HUMERAL IMMUNE RESPONSE AGAINST FIELD IBV VACCINE

The current work was established to assess the impact of indoor air quality (IAQ) (climate elements Ta.C, RH %, and AV m/sec. and ammonia ppm) on humeral immune response (HIR) against infectious bronchitis vaccine (IBV) in cool and non-cool seasons in broiler farms. Field investigation was carried out on available16 commercial broiler farms in which chicks are apparently healthy and some manifesting respiratory symptoms. An established questionnaire was used for recording management, biosecurity indicators and level, vaccination programs and history of respiratory symptoms during cool and non-cool seasons. On-site measuring of IAQ from different sites in farm. Random blood samples were collected for serum preparation to evaluate (HIR) using ELISA kit against IBV. The collected data were subjected to statistical analysis.The results revealed that, both of Ta.C and AVm/sec. revealed a high significant difference in mean values between cool and non-cool seasons. RH% means value was lower in cool compared with non-cool seasons. In non-cool seasons the indoor climate elements revealed significant correlations between each other basically RH% with both Ta.C and AV m/sec.The recorded significant correlations were clarified the impact of indoor RH% and AV m/se .on broiler HIR. The mean values of
AV m /sec increased in both seasons than recommended. Cool seasons showed lower Ta.C, RH% and AV m/ sec with higher ammoniaVs. non-cool seasons. A higher significant difference in means value and mean differences of Ta.C and air velocity recorded in cool seasons than non-cool ones. Decreased means value of antibodies titer against field vaccine or The decreased HIR titer in cool seasons was associated with lower Ta.C, RH% and air velocity but increased ammonia Vs. non-cool seasons. A high significant difference in mean values of IBV antibodies titer was noticed between cool and non-cool seasons. The recorded CV% and vaccination index (VI) revealed that, the lowest CV was in 3/15 of farms (20%) with the highest antibodies titer .The lowest VI was associated with the highest  CV% and the lowest antibodies titer were recorded in 5/15 of farms (33.3%). Conclusion, seasonal impact was clarified via significant correlations between climate elements each other (RH% with both Ta.C and AV m/sec.) in non- cool seasons. In cool seasons, decreased titer was associated with lower Ta.C, RH% and AV m/sec. The lowest VI with the highest CV% and the lowest antibodies titer were recorded in 5/15 of farms (33.33%). The seasonal climate elements and indoor air ammonia impact were entangled with recorded field applied
biosecurity. infection was reported in cool seasons compared with non-cool seasons