2024-03-28T18:36:17Zhttp://buleria.unileon.es/oai/requestoai:buleria.unileon.es:10612/107322020-12-10T09:02:43Zcom_10612_17col_10612_18
2019-05-12T23:51:29Z
urn:hdl:10612/10732
Comparison of growth performance and immune responses of broiler chicks reared under heat stress, cold stress and thermoneutral conditions
Olfati, Ali
Mojtahedin, Ali
Sadeghi, Tayebeh
Akbari, Mohsen
Martínez Pastor, Felipe
Biologia Celular
Veterinaria
P. 1-7
This study was conducted to compare the effects of thermal stress on growth performance and some immunity variables of broiler chickens. Birds were randomly assigned to one of three thermal treatments as follows: cold stress (CS, 12±1 °C), (b) heat stress (HS, 33±3 °C) and (c) thermoneutral (TN, 24±2 °C). Body weight gain (BWG), feed intake (FI), water intake (WI) and feed conversion ratio (FCR) were recorded. In order to evaluate the primary and secondary humoral immune responses, two birds per replicate were intravenously administrated with a suspension of 7% sheep red blood cell (SRBC) at 28 and 35 days. The heat-stressed broiler chickens had lower FI (-14.90%), BWG (-25.71%) and higher FCR (+13.06%) in comparison to broiler chickens reared under TN condition (p<0.001) from 1 to 42 days of age. The cold-stressed broiler chickens showed lower FI (-22.05%), BWG (-38.32%) and higher FCR (+22.47%) in comparison to birds reared under TN conditions (p<0.001). Stressed birds (CS and HS) showed decreased antibody titer against SRBC, lymphocyte count and the relative weights of lymphoid organs and increased heterophil count, heterophil to lymphocyte ratio and the serum concentration of corticosterone, in comparison to birds in TN group (p<0.001). In conclusion, HS and CS conditions have similar negative effects on performance and immunity of broiler chickens.
2019-05-12T23:51:29Z
2019-05-12T23:51:29Z
2019-05-13
info:eu-repo/semantics/article
Spanish Journal of Agricultural Research, 2018, vol. 16, n. 2
http://revistas.inia.es/index.php/sjar/article/view/12753
http://hdl.handle.net/10612/10732
Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria