Seasonal Variation in Bovine Luteal Concentrations of ß-Carotene

ß-Carotene is present in extremely high concentrations in bovine corpus luteum. The aim of this study was to examine the extent of the seasonal variation in concentrations of luteal ß-carotene in cows. A total of 102 corpora lutea collected throughout all 12 months of the year were analysed by high performance liquid chromatography (HPLC). The mean ß-carotene concentration of the luteal tissues was 58.7 ± 4.5 μg/g. Bovine corpora lutea collected in the warmer months (May-Oct.) contained significantly (P<0.01) higher ß-carotene concentrations than those corpora lutea collected in the cold months (Nov-Apr). However, the ß-carotene concentrations of luteal tissues were highly variable among the animals used in the study. The ß-carotene content of individual bovine corpora lutea ranged from 5.8 μg to 216 μg per gram of tissue. The results of the present study show the fact that bovine corpora lutea collected in summer contained more ß-carotene than those collected in winter, indicating the existence of a feed-dependent factor on ß-carotene accumulation in bovine luteal tissue.