title: Effect of heat exposure on gene expression of feed intake regulatory peptides in laying hens.
abstract: The aim of this paper was to investigate the effect of heat stress on the regulation of appetite-associated genes in laying hens. Forty eight laying hens were randomly divided into two circumstances: high (31 ± 1.5°C; relative humidity, 82.0 ± 2.2%) or normal (20 ± 2°C, control; relative humidity, 60.1 ± 4.5%) ambient environment. Heat stress decreased body weight gain (P < 0.01), feed intake (P < 0.01), laying rate (P < 0.05), average egg mass (P < 0.01), egg production (P < 0.01), shell thickness (P < 0.01), and feed efficiency (P < 0.05). High ambient temperature decreased plasma uric acid (P < 0.05). Heat stress significantly increased mRNA levels of ghrelin and cocaine- and amphetamine-regulated transcript (P < 0.05) and decreased mRNA levels of cholecystokinin (P < 0.05) in the hypothalamus. Heat stress significantly increased (P < 0.05) mRNA levels of ghrelin in the glandular stomach and jejunum but significantly decreased (P < 0.05) mRNA levels of cholecystokinin in the duodenum and jejunum. In conclusion, heat stress plays a unique role in some special neuropeptides (e.g., ghrelin, cocaine- and amphetamine-regulated transcript, and cholecystokinin), which might participate in the regulation of feed intake in laying hens under high ambient temperature.
authors.affiliation: Department of Animal Science, Shandong Agricultural University, Taian, Shandong 271018, China.
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Song
authors.forename: Lei
authors.initials: L
authors.lastname: Liu
authors.forename: Ardashir
authors.initials: A
authors.lastname: Sheikhahmadi
authors.forename: Hongchao
authors.initials: H
authors.lastname: Jiao
authors.forename: Hai
authors.initials: H
authors.lastname: Lin
mesh_terms: D000818:Animals; D001069:Appetite Regulation / Q000502:physiology; D001835:Body Weight / Q000502:physiology; D002645:Chickens / Q000502:physiology*; D002766:Cholecystokinin / Q000096:biosynthesis / Q000097:blood / Q000235:genetics / Q000378:metabolism; D052284:Clutch Size; D004435:Eating / Q000502:physiology*; D004528:Egg Shell / Q000502:physiology; D005260:Female; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000502:physiology*; D018869:Heat-Shock Response / Q000502:physiology*; D007031:Hypothalamus / Q000378:metabolism; D009479:Neuropeptides / Q000096:biosynthesis / Q000097:blood / Q000235:genetics / Q000378:metabolism; D009928:Organ Specificity; D010058:Oviposition; D036361:Peptide Hormones / Q000096:biosynthesis / Q000097:blood / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D009479:Neuropeptides; D036361:Peptide Hormones; D012333:RNA, Messenger; D002766:Cholecystokinin