The present study was conducted to investigate the variations in blood serum and hepatic levels of vitamin A and b-carotene in Ghezel sheep throughout the year. From 1000 sheep aged 1-5 years, blood and liver samples were collected before and after slaughter. The levels of vitamin A and \beta-carotene in both samples were determined spectrophotometrically. The results showed significant differences between summer and winter values (P < 0.05), but no differences were found between the sexes (P > 0.05). There were significant correlations between the vitamin A levels in serum and the liver (P < 0.05). Due to low levels of vitamin A and \beta -carotene in Ghezel sheep during the winter, supplementary feeding of vitamin A is recommended during this season.
AFSHARI, GHOLAMREZA; HASANPOUR, A.; HAGHPANAH, H.; and AMOUGHLI-TABRIZI, BAHRAM (2008) "Seasonal Variation of Vitamin A and Beta-Carotene Levels in Ghezel Sheep," Turkish Journal of Veterinary & Animal Sciences: Vol. 32: No. 2, Article 11. Available at: https://journals.tubitak.gov.tr/veterinary/vol32/iss2/11