Effects of free gossypol in the diet of pregnant and postpartum Brahman cows on calf development and cow performance.
Pregnant Brahman cows (n = 38) and heifers (n = 12) were assigned, 90 d before expected calving dates, to one of three treatment groups: 1) 0 g of free gossypol(FG).animal-1.d-1 (FGHD) from soybean meal (SBM), controls; 2) 2 g of FGHD from SBM and cottonseed meal (CSM), low FG; or 3) 4 g of FGHD from CSM, high FG, to determine the effects of dietary FG on prepartum and postpartum cow performance, calf development, and selected blood variables. Prepartum and postpartum cow BW, 4-h milk production, and calf BW were similar (P > .10) among treatments. Following 84 d of treatment, cows receiving 4 g of FGHD tended (P < .10) to have greater erythrocyte fragility (EF) than cows given 0 or 2 g of FGHD. Mean EF for the 112-d postpartum period were greater (P < .05) in cows given 4 than in those given 0 g of FGHD. Dietary FG consumption by the dam did not affect (P > .10) calf EF. Serum triiodothyronine (T3) and thyroxine (T4) in cows and T4:T3 ratio in calves were similar (P > .10) among treatments. After 84 d of treatment, cows receiving 4 g of FGHD had lower (P < .05) serum concentrations of alpha-tocopherol and beta-carotene than cows given 0 g of FGHD. At parturition, serum alpha-tocopherol and beta-carotene were similar (P > .10) for all cows and calves. On d 7 and 28 after calving, alpha-tocopherol tended to be lower (P < .10) and beta-carotene was lower (P < .05) in calves given 4 than in those given 0 g of FGHD. Calf metacarpal medial cortex tended to be greater (P < .10) in calves from cows given 0 than in those from cows given 2 or 4 g of FGHD, and the lateral cortex (treatment x sex; P < .05) was smaller in male calves from cows given 4 than in those from cows given 0 g of FGHD but was not affected in female calves. By 96 to 105 d after calving, a greater number of (P < .05) cows consuming 4 and 2 g of FGHD experienced luteal activity, and a greater (P < .10) number than of cows receiving 0 g of FGHD had conceived by 112 d after calving. In summary, pre- and postpartum consumption of FG may have impaired some aspects of calf skeletal development and vitamin metabolism, although long-term performance of cows and calves was not affected.
Willard
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Texas A&M University, Texas Agricultural Experiment Station, Overton 75684, USA.
Neuendorff
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Lewis
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Randel
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D000085:Acetates / Q000097:blood; D000818:Animals; D000833:Animals, Suckling / Q000097:blood / Q000254:growth & development* / Q000502:physiology; D001806:Blood Urea Nitrogen; D001846:Bone Development / Q000187:drug effects / Q000502:physiology; D002338:Carotenoids / Q000097:blood; D002417:Cattle / Q000097:blood / Q000254:growth & development* / Q000502:physiology; D003369:Cottonseed Oil / Q000737:chemistry / Q000592:standards; D004032:Diet / Q000662:veterinary; D004907:Erythrocyte Deformability; D005260:Female; D005527:Food, Fortified; D006072:Gossypol / Q000032:analysis / Q000494:pharmacology*; D008297:Male; D049590:Postpartum Period / Q000502:physiology*; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000502:physiology*; D011897:Random Allocation; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood; D014810:Vitamin E / Q000097:blood
D000085:Acetates; D003369:Cottonseed Oil; D014284:Triiodothyronine; D014810:Vitamin E; D002338:Carotenoids; D006072:Gossypol; D013974:Thyroxine