title: Domperidone can ameliorate deleterious reproductive effects and reduced weight gain associated with fescue toxicosis in heifers.
abstract: The aim of this study was to evaluate the effect of a dopamine antagonist, domperidone, in nonpregnant, reproductively cycling heifers consuming endophyte-infected (EI) fescue diets. Thirty crossbred heifers (Angus x Holstein or Hereford x Holstein) were assigned to one of three treatment groups (n = 10); endophyte-free (EF) fescue diet, EI fescue diet, or endophyte-infected diet and treated with domperidone (EID). Heifers fed EI diets had decreased weight gains compared with heifers fed EF or EID (P < 0.05) during a 21-d treatment period. Ovarian structures were monitored via transrectal ultrasound to determine follicle size and day of ovulation. Blood plasma samples were collected daily and analyzed for progesterone concentration to determine luteal function. Heifers ingesting EI diets had estrous cycles of shorter duration and lower mid-cycle progesterone concentrations than heifers in the EF or EID treatments (P < 0.05). Ovaries from a subset of heifers in each group (n = 3 per group) were harvested and in vitro secretion of progesterone from luteal tissue extracts was determined. No differences in progesterone concentrations were detected among luteal tissue incubates (P > 0.05). These results suggest that domperidone supplementation of heifers consuming EI fescue may ameliorate certain symptoms of fescue toxicosis.
authors.affiliation: Department of Animal Science, Food & Nutrition, Southern Illinois University Carbondale, Carbondale, USA. kljones@siu.edu
authors.forename: K L
authors.initials: KL
authors.lastname: Jones
authors.forename: S S
authors.initials: SS
authors.lastname: King
authors.forename: K E
authors.initials: KE
authors.lastname: Griswold
authors.forename: D
authors.initials: D
authors.lastname: Cazac
authors.forename: D L
authors.initials: DL
authors.lastname: Cross
mesh_terms: D000164:Acremonium; D000821:Animal Feed / Q000009:adverse effects; D000818:Animals; D002417:Cattle / Q000097:blood / Q000502:physiology*; D004294:Domperidone / Q000494:pharmacology*; D018492:Dopamine Antagonists / Q000494:pharmacology*; D004971:Estrus / Q000187:drug effects / Q000502:physiology; D005260:Female; D005506:Food Contamination; D010053:Ovary / Q000000981:diagnostic imaging / Q000187:drug effects; D006109:Poaceae / Q000382:microbiology*; D011374:Progesterone / Q000097:blood; D011897:Random Allocation; D012098:Reproduction / Q000187:drug effects*; D014463:Ultrasonography; D015430:Weight Gain / Q000187:drug effects*
chemical_list: D018492:Dopamine Antagonists; D011374:Progesterone; D004294:Domperidone