title: Effects of oral supplementation with β-carotene on concentrations of β-carotene, vitamin A and α-tocopherol in plasma, colostrum and milk of mares and plasma of their foals and on fertility in mares.
abstract: In this study, effects of oral β-carotene supplementation to mares (β-carotene group: 1000 mg/day, n = 15; control group: n = 15) from 2 weeks before foaling until 6 weeks thereafter on concentrations of β-carotene, vitamin A and α-tocopherol in plasma, colostrum and milk and plasma of their foals were determined. In addition, effects on fertility were studied. Beta-carotene concentrations increased in plasma and colostrum of β-carotene-supplemented mares compared to control mares (p < 0.05). In mares of both groups, β-carotene concentrations were higher in colostrum than in milk (p < 0.05). In foals, β-carotene concentrations increased with colostrum uptake and were higher in foals born to supplemented mares (p < 0.05; control group: 0.0003 ± 0.0002 μg/ml on day 0, 0.008 ± 0.0023 μg/ml on day 1; β-carotene group: 0.0005 ± 0.0003 μg/ml on day 0, 0.048 ± 0.018 μg/ml on day 1). Concentrations of vitamin A and α-tocopherol were higher in colostrum than in milk (p < 0.05) but did not differ between groups. Concentration of α-tocopherol in plasma of mares decreased over time and in foals, increased markedly within 4 days after birth. All but one mare (control group) showed oestrus within 2 weeks post-partum. Occurrence of oestrus did not differ between groups. More mares of the control group (7/7 vs. 5/12 in the β-carotene group) became pregnant after being bred in first post-partum oestrus (p < 0.05). In conclusion, β-carotene supplementation to mares increased β-carotene concentrations in plasma, colostrum and milk of mares and plasma of their foals but had no positive effects on fertility.
authors.affiliation: Graf Lehndorff Institute for Equine Science, Neustadt (Dosse), Germany. juliane.kuhl@vetmeduni.ac.at
authors.forename: J
authors.initials: J
authors.lastname: Kuhl
authors.forename: J E
authors.initials: JE
authors.lastname: Aurich
authors.forename: M
authors.initials: M
authors.lastname: Wulf
authors.forename: A
authors.initials: A
authors.lastname: Hurtienne
authors.forename: F J
authors.initials: FJ
authors.lastname: Schweigert
authors.forename: C
authors.initials: C
authors.lastname: Aurich
mesh_terms: D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D003126:Colostrum / Q000737:chemistry*; D019587:Dietary Supplements; D005260:Female; D005298:Fertility / Q000187:drug effects; D006736:Horses / Q000097:blood*; D039382:Maternal Nutritional Physiological Phenomena; D008892:Milk / Q000737:chemistry*; D011247:Pregnancy; D014801:Vitamin A / Q000097:blood* / Q000737:chemistry; D024502:alpha-Tocopherol / Q000097:blood* / Q000737:chemistry; D019207:beta Carotene / Q000097:blood / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D019207:beta Carotene; D014801:Vitamin A; D024502:alpha-Tocopherol