title: Effects of dexamethasone and colostrum intake on the somatotropic axis in neonatal calves.
abstract: Glucocorticoids and colostrum feeding influence postnatal maturation of the somatotropic axis. We have tested the hypothesis that dexamethasone (Dexa) affects the somatotropic axis in neonatal calves dependent on colostrum intake. Calves were fed either with colostrum or with a milk-based formula (n = 14/group), and, in each feeding group, one-half of the calves were treated with Dexa (30 micro g. kg body wt-1. day-1). Pre- and postprandial blood samples were taken on days 1, 2, 4, and 5, and liver samples were taken on day 5 of life. Dexa increased insulin-like growth factor (IGF)-I, but decreased growth hormone (GH) and IGF-binding protein (IGFBP)-1 and -2 plasma concentrations and increased GH receptor (GHR) mRNA levels in liver. Dexa increased IGF-I mRNA levels only in formula-fed calves and increased hepatic GHR binding capacity, but only in colostrum-fed calves. Colostrum feeding decreased IGFBP-1 and -2 plasma concentrations and hepatic IGFBP-2 and -3 mRNA levels. In conclusion, Dexa and colostrum feeding promoted maturation of the somatotropic axis. Dexa effects partly depended on whether colostrum was fed or not.
authors.affiliation: Div. of Animal Nutrition and Physiology, Univ. of Berne, Route de la Tioleyre 4, CH-1725 Posieux, Switzerland.
authors.forename: Stephanie N
authors.initials: SN
authors.lastname: Sauter
authors.forename: Edgar
authors.initials: E
authors.lastname: Ontsouka
authors.forename: Bettina
authors.initials: B
authors.lastname: Roffler
authors.forename: Yolande
authors.initials: Y
authors.lastname: Zbinden
authors.forename: Chantal
authors.initials: C
authors.lastname: Philipona
authors.forename: Michael
authors.initials: M
authors.lastname: Pfaffl
authors.forename: Bernhard H
authors.initials: BH
authors.lastname: Breier
authors.forename: Jürg W
authors.initials: JW
authors.lastname: Blum
authors.forename: Harald M
authors.initials: HM
authors.lastname: Hammon
mesh_terms: D000375:Aging; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D000831:Animals, Newborn / Q000502:physiology*; D001835:Body Weight; D002417:Cattle / Q000254:growth & development / Q000502:physiology*; D003126:Colostrum; D003907:Dexamethasone / Q000494:pharmacology*; D004435:Eating; D005938:Glucocorticoids / Q000494:pharmacology*; D013006:Growth Hormone / Q000097:blood / Q000502:physiology*; D006304:Health Status; D018970:Insulin-Like Growth Factor Binding Protein 1 / Q000097:blood; D018971:Insulin-Like Growth Factor Binding Protein 2 / Q000097:blood / Q000235:genetics; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000235:genetics; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D008099:Liver / Q000737:chemistry; D008892:Milk; D012333:RNA, Messenger / Q000032:analysis; D011986:Receptors, Somatotropin / Q000235:genetics
chemical_list: D005938:Glucocorticoids; D018970:Insulin-Like Growth Factor Binding Protein 1; D018971:Insulin-Like Growth Factor Binding Protein 2; D018972:Insulin-Like Growth Factor Binding Protein 3; D012333:RNA, Messenger; D011986:Receptors, Somatotropin; D007334:Insulin-Like Growth Factor I; D003907:Dexamethasone; D013006:Growth Hormone