title: The effect of increasing feeding frequency on performance, plasma hormones and metabolites, and hepatic lipid metabolism of broiler breeder hens.
abstract: An experiment was conducted to study the effects of feeding regimens on reproductive performance, plasma hormone and metabolite levels, and hepatic lipid metabolism of Cobb 500 broiler breeder hens from 26 to 38 wk of age. Seventy-two birds were used in a completely randomized design with 3 treatments, each replicated 4 times. Treatments were as follows: 1) once a day feeding, in which birds were fed once a day at 0615 h (control), 2) twice a day feeding, in which daily allocated feed was fed in 2 equal meals at 0615 and 1215 h, and 3) thrice a day feeding in which daily allocated feed was offered in 3 equal meals at 0615, 1215, and 1815 h. Through 38 wk of age, total hen-day egg production in the hens fed twice and thrice a day was greater (67.1 and 67.2 vs. 62.2 eggs/hen, P < 0.01). Similarly, egg weight was higher (P < 0.01) in birds fed more than once a day. Multi-meal-fed birds had significantly lower plasma triiodothyronine and glucose at 32 wk and also lower glucose and cholesterol, and higher 17β-estradiol levels at 38 wk than those fed once a day (P ≤ 0.05). Hepatic expression of malic enzyme, fatty acid synthase, acetyl-CoA carboxylase, and ATP citrate lyase relative to β-actin decreased (P < 0.05) in birds fed twice and thrice a day compared with birds fed once a day at peak egg production (32 wk). In contrast, feeding regimens did not affect the hepatic gene expression of lipogenic enzymes after peak egg production at 38 wk. Stearoyl-CoA desaturase 1 (SCD1) gene expression was constant over dietary regimens. There was no difference in malic enzyme activity in multi-meal-fed birds at 38 wk. In summary, feeding broiler breeder hens 2 or 3 meals per day improved the reproductive performance during the early lay cycle. Implementing twice or thrice a day feeding regimens altered hepatic lipogenic gene expression in broiler breeder hens only at peak egg production, which indicated a short-term effect of increasing feeding frequency on hepatic lipid metabolism.
authors.affiliation: Department of Animal Science, University of Tehran, Karaj 31587-11167, Iran. somoradi@ut.ac.ir
authors.forename: S
authors.initials: S
authors.lastname: Moradi
authors.forename: M
authors.initials: M
authors.lastname: Zaghari
authors.forename: M
authors.initials: M
authors.lastname: Shivazad
authors.forename: R
authors.initials: R
authors.lastname: Osfoori
authors.forename: M
authors.initials: M
authors.lastname: Mardi
mesh_terms: D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001774:Blood Chemical Analysis / Q000662:veterinary; D002645:Chickens / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D004032:Diet / Q000662:veterinary; D005247:Feeding Behavior; D005260:Female; D005786:Gene Expression Regulation; D006728:Hormones / Q000097:blood; D050356:Lipid Metabolism; D008099:Liver / Q000201:enzymology*; D012313:RNA / Q000378:metabolism; D011897:Random Allocation; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D012098:Reproduction; D013997:Time Factors
chemical_list: D006728:Hormones; D012313:RNA