title: Influence of somatotropin and nutrition on bovine oocyte retrieval and in vitro development.
abstract: The objective of this study was to determine the effects of supplemental bovine somatotropin (bST) and limit feeding on follicular growth and oocyte competence in yearling beef heifers. Sixteen growing heifers (424+/-4 kg) were randomly assigned to 1 of 4 treatments in a 2 x 2 factorial arrangement, with main effects of bST (0 or 33 microg/kg BW/d) and feeding regimen (ad libitum or 0.75 ad libitum intake). Animals were treated for 100 d prior to follicular aspiration, and treatments continued for the 42-d period that follicles were aspirated. Follicles were observed ultrasonically then aspirated, and recovered oocytes were matured, fertilized and developed in vitro. The number of follicles observed ultrasonically was greater with bST treatment (P<0.01) but was unchanged by plane of nutrition. The number and quality of recovered oocytes were similar among treatments, as was the number of oocytes resulting in blastocyst formation.
authors.affiliation: Department of Animal Science, University of Connecticut, Storrs 06269-4040, USA.
authors.forename: M W
authors.initials: MW
authors.lastname: Tripp
authors.forename: J C
authors.initials: JC
authors.lastname: Ju
authors.forename: T A
authors.initials: TA
authors.lastname: Hoagland
authors.forename: J W
authors.initials: JW
authors.lastname: Riesen
authors.forename: X
authors.initials: X
authors.lastname: Yang
authors.forename: S A
authors.initials: SA
authors.lastname: Zinn
mesh_terms: D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001835:Body Weight; D002417:Cattle / Q000378:metabolism / Q000502:physiology*; D004973:Estrus Synchronization / Q000502:physiology; D005260:Female; D005307:Fertilization in Vitro / Q000662:veterinary*; D005508:Food Deprivation / Q000502:physiology; D013006:Growth Hormone / Q000502:physiology*; D016018:Least-Squares Analysis; D008297:Male; D009865:Oocytes / Q000502:physiology*; D011897:Random Allocation; D013396:Suction / Q000662:veterinary
chemical_list: D013006:Growth Hormone