beta-Carotene, Retinol and alpha-Tocopherol Status in Calves Fed the First Colostrum at 0–2, 6-7, 12-13 or 24-25 Hours after Birth

Effects on beta-carotene, retinol and alpha-tocopherol status of feeding 1st colostrum at 0–2, 6–7, 12–13 and 24–25 h after birth were studied in calves. beta-carotene, retinol and alpha-tocopherol concentrations decreased in colostrum during the first 2.5 d of laxtation. Plasma beta-carotene, retinol and alpha-tocopherol concentrations in newborn calves were very low. Plasma beta-carotene concentrations increased up to d 3 after the 1st meal and during the 1st month were higher in calves fed 1st colostrum at < 6–7 h than at > 12–13 h after birth. Plasma retinol concentrations increased up to d 5 after the 1st meal and were higher during the 1st month in calves fed 1st colostrum at < 12–13 h than at > 24–25 h after birth, whereas hepatic concentrations increased up to d 5 independent of time of 1st colostrum feeding. Plasma alpha-tocopherol concentrations increased after the 1st meal except in calves fed 1st colostrum at 24–25 h after birth and were higher during the 1st month in calves fed the 1st colostrum at 6–7 h than at 24–25 h after birth. In conclusion, delaying 1st colostrum intake by more than 12–13 h after birth impaired the plasma beta-carotene, retinol and alpha-tocopherol status during the 1st month of life, but did not negatively influence hepatic retinol concentrations.