Vitamin A is one of the fat-soluble vitamins. Because of its particular role in different tissues and organs, in deficiency conditions various clinical signs are seen. In addition, sometimes the marginal deficiency is present that clinical signs are not visible but performance defects, such as infertility is seen. In present study changes of serum /3- carotene and vitamin A from birth to 4 months age old in 10 Holstein calves were investigated in summer 2004. A simple and cheep method (spectrophotometery) was used for measuring vitamin A and /3-carotene. The results were analyzed statistically by Paired T test and Friedmant test. In this study the values of mean of serum /3-carotene and vitamin A were 12.90.9 and 77.2 5.1 gld1, respectively. Also, the results show the mean values of serum vitamin A and /3-carotene significantly increased after taking colostrum.

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