title: Effects of corticosterone and dietary energy on immune function of broiler chickens.
abstract: An experiment was conducted to investigate the effects of dietary energy level on the performance and immune function of stressed broiler chickens (Gallus gallus domesticus). A total of 96 three-day-old male broiler chickens (Ross × Ross) were divided into two groups. One group received a high energy (HE) diet and the other group received a low energy (LE) diet for 7 days. At 5 days of age, the chickens from each group were further divided into two sub-groups and received one of the following two treatments for 3 days: (1) subcutaneous injection of corticosterone, twice per day (CORT group; 2 mg of CORT/kg BW in corn oil) and (2) subcutaneous injection of corn oil, twice per day (Control/Sham treatment group). At 10 days of age, samples of blood, duodenum, jejunum, and ileum were obtained. Compared with the other three groups, the LE group treated with CORT had the lowest average daily gain (ADG) and the poorest feed conversion ratio (FCR, P < 0.05). Furthermore, CORT treatment decreased the relative weight (RW) of the bursa independent of the dietary energy level, but it decreased the RW of the thymus only in the chickens fed the LE diet. By contrast, CORT administration decreased the RW of the spleen only in the chickens fed the HE diet (P < 0.05). The plasma total protein, albumin, tumor necrosis factor alpha, interleukin 2 and immunoglobulin G (IgG) levels were affected by the CORT treatment (P < 0.05); however, these factors were not significantly affected by the dietary energy level. Toll-like receptor-5 mRNA level was down-regulated by CORT injection in the duodenum and ileum (P < 0.05) and showed a trend of down-regulation in the jejunum (P=0.0846). The present study showed that CORT treatment induced immunosuppressive effects on the innate immune system of broiler chickens, which were ameliorated by consumption of higher dietary energy.
authors: Department of Animal Science, Shandong Agricultural University, Taian, Shandong 271018, China.
authors: Jiachang
authors: J
authors: Yang
authors: Department of Animal Science, Shandong Agricultural University, Taian, Shandong 271018, China.
authors: Lei
authors: L
authors: Liu
authors: Department of Animal Science, Faculty of Agriculture, University of Kurdistan, Sanandaj 66177-15175, Iran.
authors: Ardashir
authors: A
authors: Sheikhahmadi
authors: Laboratory of Livestock Physiology, Department of Biosystems, KU Leuven, Kasteelpark Arenberg, 30, 3001 Leuven, Belgium.
authors: Yufeng
authors: Y
authors: Wang
authors: Laboratory of Livestock Physiology, Department of Biosystems, KU Leuven, Kasteelpark Arenberg, 30, 3001 Leuven, Belgium.
authors: Congcong
authors: C
authors: Li
authors: Department of Animal Science, Shandong Agricultural University, Taian, Shandong 271018, China.
authors: Hongchao
authors: H
authors: Jiao
authors: Department of Animal Science, Shandong Agricultural University, Taian, Shandong 271018, China.
authors: Hai
authors: H
authors: Lin
authors: Department of Animal Science, Shandong Agricultural University, Taian, Shandong 271018, China.
authors: Zhigang
authors: Z
authors: Song
mesh_terms: D000818:Animals; D002645:Chickens / Q000097:blood / Q000235:genetics / Q000254:growth & development / Q000276:immunology*; D003345:Corticosterone / Q000494:pharmacology*; D002149:Energy Intake; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000187:drug effects; D008297:Male; D009929:Organ Size / Q000187:drug effects / Q000276:immunology; D059467:Transcriptome / Q000187:drug effects / Q000276:immunology
chemical_list: D003345:Corticosterone