title: Differences in the expression of genes involved in the somatotropic axis in divergent strains of Holstein-Friesian dairy cows during early and mid lactation.
abstract: Differences in genetic selection criteria for dairy cows internationally have led to divergence in the Holstein-Friesian breed. The objective of this study was to compare hepatic expression of genes of the somatotropic axis in the North American Holstein-Friesian and the New Zealand Holstein-Friesian strains of dairy cow at early and mid lactation. Mature cows of both the North American Holstein-Friesian (n = 10) and New Zealand Holstein-Friesian (n = 10) strains were selected. Liver tissue was collected by percutaneous punch biopsy from all cows at 35 and 140 d postpartum, representing early and mid lactation, respectively. Total RNA was extracted and the hepatic expression of genes involved in the control of the somatotropic axis was examined. Abundance of insulin-like growth factor (IGF)-1 mRNA was greater in the New Zealand strain, concomitant with a tendency for increased expression of acid-labile subunit mRNA. Across strains, mRNA abundance of IGF-binding protein-1, IGF-binding protein-2, and growth hormone receptor 1A decreased from d 35 to 140 postpartum, whereas expression of IGF-1 and acid-labile subunit tended to increase. Abundance of suppressor of cytokine signaling-3 mRNA was increased at d 140 postpartum. Both the strain of Holstein-Friesian cow and the stage of lactation influenced expression of genes controlling the somatotropic axis in hepatic tissue.
authors.affiliation: Teagasc, Animal Production Research Centre, Athenry, Co Galway, Ireland.
authors.forename: S D
authors.initials: SD
authors.lastname: McCarthy
authors.forename: S T
authors.initials: ST
authors.lastname: Butler
authors.forename: J
authors.initials: J
authors.lastname: Patton
authors.forename: M
authors.initials: M
authors.lastname: Daly
authors.forename: D G
authors.initials: DG
authors.lastname: Morris
authors.forename: D A
authors.initials: DA
authors.lastname: Kenny
authors.forename: S M
authors.initials: SM
authors.lastname: Waters
mesh_terms: D000818:Animals; D002417:Cattle / Q000235:genetics*; D005260:Female; D005786:Gene Expression Regulation; D018969:Insulin-Like Growth Factor Binding Proteins / Q000235:genetics*; D007334:Insulin-Like Growth Factor I / Q000235:genetics*; D007774:Lactation / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D011986:Receptors, Somatotropin / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013045:Species Specificity; D050826:Suppressor of Cytokine Signaling Proteins / Q000235:genetics
chemical_list: D018969:Insulin-Like Growth Factor Binding Proteins; D012333:RNA, Messenger; D011986:Receptors, Somatotropin; D050826:Suppressor of Cytokine Signaling Proteins; D007334:Insulin-Like Growth Factor I