Effects of methionine supplementation on the expression of protein deposition-related genes in acute heat stress-exposed broilers.

The objective of this study was to evaluate the effect of heat stress and methionine supplementation on the gene expression of insulin-like growth factor I (IGF-I), growth hormone receptor (GHR), phosphatidylinositol 3-kinase, and regulatory 1 (PI3KR1) in the liver, as well as the expression of the atrogin 1 and cathepsin L2 (CTSL2) genes in the breast muscle of broilers. Broilers from 1-21 and 22-42 days of age were divided into three treatments related to methionine supplementation as follows: without methionine supplementation (MD), recommended level of methionine (DL1), and excess supplementation of methionine (DL2). The animals were either maintained at a thermal comfort temperature or exposed to heat stress (HS) (38°C for 24 hours, starting on day 20 or day 41 for experiments 1 and 2, respectively).

Thermal stress induces changes in gene expression and blood parameters in high and low feed efficiency meat quail.

In this study, we analysed markers of stress, plasma creatinine and T3 content, and insulin-like growth factor I (IGF-I), growth hormone receptor (GHR), uncoupling protein (UCP), adenine nucleotide translocase (ANT) and cytochrome c oxidase subunit III (COX III) mRNA expression in the liver and muscle of high (0.22 g/g) and low (0.14 g/g) feed efficiency (FE) meat quail at three different air temperatures, comfortable, heat and cold stress, for 24 h.