title: Effects of energy source in the diet on reproductive hormones and insulin during lactation and subsequent estrus in multiparous sows.
abstract: Two experiments were performed. The first experiment was done to study the effects of dietary energy source on plasma insulin concentration using five gilts in a Latin square design with two diets over two periods. The diets contained either 200 g/kg of cornstarch (Starch) or soybean oil (Fat) as energy sources. Results indicate that insulin response was greater in the Starch-fed than in the Fat-fed gilts. A second experiment was performed in which 18 multiparous sows were fed one of the two experimental diets from farrowing until slaughter at d 35 of subsequent pregnancy. All sows nursed nine pigs. Blood samples were taken from a permanent jugular vein catheter every 12 min during a 12-h period on d 109 +/- 1 of pregnancy, on d 7 +/- 1, 14 +/- 1, and 21 +/- 1 of lactation, and on the day of weaning ( d 22 +/- 1). From 48 h after weaning, blood samples were taken every 4 h until 24 h after ovulation. After that, blood samples were taken at 12-h intervals until d 10 after ovulation. Differences between diets in insulin response were not significant. In Starch-fed sows, LH pulsatility at d 7 of lactation was greater (P < .05), the preovulatory LH surge was greater ( P < .05), and progesterone production was greater (P < .05) from 108 h until 256 h after the LH surge than in the Fat-fed sows. Results indicate that feeding Starch-rich diets to multiparous sows compared with Fat-rich diets, on an isocaloric basis, increases LH pulsatility during early lactation, the preovulatory LH surge, and progesterone production after the LH surge.
authors.affiliation: Department of Animal Husbandry, Wageningen Agricultural University, The Netherlands.
authors.forename: B
authors.initials: B
authors.lastname: Kemp
authors.forename: N M
authors.initials: NM
authors.lastname: Soede
authors.forename: F A
authors.initials: FA
authors.lastname: Helmond
authors.forename: M W
authors.initials: MW
authors.lastname: Bosch
mesh_terms: D000818:Animals; D001835:Body Weight / Q000502:physiology; D004040:Dietary Carbohydrates / Q000494:pharmacology; D004041:Dietary Fats / Q000494:pharmacology; D004435:Eating / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology; D004958:Estradiol / Q000097:blood*; D004971:Estrus / Q000378:metabolism* / Q000502:physiology; D005260:Female; D005313:Fetal Death / Q000662:veterinary; D007328:Insulin / Q000097:blood*; D007774:Lactation / Q000378:metabolism* / Q000502:physiology; D007986:Luteinizing Hormone / Q000097:blood*; D010060:Ovulation / Q000378:metabolism / Q000502:physiology; D011247:Pregnancy; D011374:Progesterone / Q000097:blood*; D013024:Soybean Oil / Q000008:administration & dosage / Q000494:pharmacology; D013213:Starch / Q000008:administration & dosage / Q000494:pharmacology; D013552:Swine / Q000097:blood* / Q000502:physiology
chemical_list: D004040:Dietary Carbohydrates; D004041:Dietary Fats; D007328:Insulin; D011374:Progesterone; D004958:Estradiol; D013024:Soybean Oil; D007986:Luteinizing Hormone; D013213:Starch