Carotenoids and vitamin a in the blood of dairy calves in Puerto Rico

Abstract

The carotene and vitamin-A content of the blood of a group of dairy calves was determined at birth, before ingestion of colostrum, 24 and 72 hours after birth, and thereafter at monthly intervals until 4 months of age. There was a significant difference in carotene and vitamin-A between ages, the relationship being best described by a straight line. Carotene and vitamin A values compared favorably with those given in the United States for normal calves. Supplementation with vitamin-A during the period comprised between the third day after birth and effective grass consumption (5 weeks of age) is considered unnecessary.