title: Dietary whole cottonseed depresses lipogenesis but has no effect on stearoyl coenzyme desaturase activity in bovine subcutaneous adipose tissue.
abstract: The primary objective of this study was to determine the effect of long-term feeding of whole cottonseed (WCS) on lipogenesis and stearoyl-coenzyme A desaturase activity in growing steers. Brangus steers were fed either a control, cornbased diet (n = 11) or 30% WCS (n = 12). The 30% WCS contributed an estimated 6.6% additional lipid to the diet. Steers fed the added WCS had greater live weights (P = 0.04) and kidney, pelvic, and heart fat (P = 0.005). Subcutaneous fat thickness was not different (P = 0.20) between treatment groups, although WCS elicited an increase in the proportion of large diameter subcutaneous adipocytes. The rate of [U-14C]acetate incorporation into fatty acids in subcutaneous adipose tissue was reduced by dietary WCS (171.4 vs 122.1 nmol x 100 mg adipose tissue-1 x 2 hr-1, P = 0.03), indicating that the increased dietary fat depressed de novo lipogenesis. Hepatic desaturase activity was much lower than that of subcutaneous adipose tissue, a feature common to cattle. We anticipated that added WCS also would depress stearoyl-coenzyme A desaturase activity in subcutaneous adipose tissue and liver due to its cyclopropene fatty acid content. Instead, desaturase activity was numerically (although not significantly) greater in liver (P = 0.37) and adipose tissue (P = 0.23).
authors.affiliation: Department of Animal Science, Texas Agricultural Experiment Station, Texas A&M University, College Station 77843-2471, USA.
authors.forename: A M
authors.initials: AM
authors.lastname: Page
authors.forename: C A
authors.initials: CA
authors.lastname: Sturdivant
authors.forename: D K
authors.initials: DK
authors.lastname: Lunt
authors.forename: S B
authors.initials: SB
authors.lastname: Smith
mesh_terms: D000273:Adipose Tissue / Q000033:anatomy & histology / Q000187:drug effects* / Q000378:metabolism*; D000818:Animals; D002417:Cattle; D003369:Cottonseed Oil / Q000008:administration & dosage*; D003864:Depression, Chemical; D008055:Lipids / Q000096:biosynthesis*; D008099:Liver / Q000187:drug effects / Q000201:enzymology; D008297:Male; D009929:Organ Size / Q000187:drug effects; D013230:Stearoyl-CoA Desaturase / Q000378:metabolism*
chemical_list: D003369:Cottonseed Oil; D008055:Lipids; D013230:Stearoyl-CoA Desaturase