Effect of acute heat stress on the physiological and reproductive parameters of broiler breeder hens-A study under controlled thermal stress Aswathi P.B., Bhanja S.K.*, Kumar Puneet1, Shyamkumar T.S., Mehra Manish, Bhaisare Darshana B, Rath Pradeepta Kumar ICAR-Central Avian Research Institute, Izatnagar, Bareilly-243 122, Uttar Pradesh, India 1ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly-243 122, Uttar Pradesh, India *Corresponding author's e-mail: subratcari@gmail.com
Online published on 15 October, 2019. Abstract A study was conducted to find out the effect of thermal stress on the physiological as well as reproductive performances of broiler breeder hens. The birds were exposed to 37±1°C and RH 70% for 6 hours daily for a period of 10 days in the psychrometric chamber (THI >90). In the heat exposed group, body weight gain and feed intake (P<0.05) were negatively affected, whereas water consumption and water: feed intake ratio were much higher during the period of study. Even after 12hrs of heat exposure, surface temperature of feathered regions; neck and back were significantly high (P<0.05). The serum cholesterol level in heat treated birds was increasing (P<0.05), whereas calcium and phosphorus levelswere showing lower values (P<0.05) on the 3rd and 10th day of study. A significant change in serum protein or glucose could not be observed. The reduction in HDEP and internal egg quality parameters like albumen index, Haugh unit score, yolk index etc. were observed in heat exposed hens (P<0.01). Higher incidence of blood spots were also noted in eggs laid by heat treated birds. In the present study, it can be concluded that thermal stress at THI>90 for at least 6hrs/day can impart serious damage to various physiological and reproductive performances in broiler breeder hens. Top Keywords Body temperature, Broiler breeder hen, Egg production, Heat stress, Serum biochemical. Top |