β-Carotene, retinol and α-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 -caxotene, retinol and alpha -tocopherol concentrations decreased in colostrum during the first 2.5 d of lactation. Plasma beta -carotene, retinol and alpha -tocopherol concentrations in new-born cdves 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 ist 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.