Résumé
Vitamin A which is found in different tissues and organs plays a particular role in detecting clinical signs in various deficiency conditions. However, sometimes the marginal deficiency is present in a way that clinical signs are not visible but performance defects, such as infertility is seen. In this study, the normal baseline levels of vitamin A and beta-carotene in clinically healthy camels [Camelus dromedarius] in the Yazd province were investigated. A total of 168 Iranian camels of both sexes were sampled from February 2009 to July 2010. Spectrophoto-metry was used for measuring the serum values. The mean +/- SE concentration of vitamin A and beta- carotene were 63.9 +/- 4.7 and 9 +/- 1.1 micro g/dL, respectively. Although, the beta-carotene concentration was significantly higher in summer, vitamin A was not influenced by season. No significant difference in the serum levels of the measured parameters was observed in different ages and sexes. The results of this study, for the first time, indicate the concentration of vitamin A and beta-carotene in the camels in Iran. This finding can be used as a reference guide for evaluation of the deficiency or excess of vitamin A and beta-carotene in camels in Iran. Furthermore, due to the lower levels of vitamin A and beta-carotene in Iranian dromedaries during winter, supplementary feeding of vitamin A is recommended during this season