The effect of beta carotene supplementation on the beta carotene and vitamin A levels of blood plasma and some fertility indices of dairy cows
Iwańska, S.; Lewicki, C.; Rybicka, M.
Archiv für Tierernahrung 35(8): 563-570
Seasonal variations in .beta. carotene intake and low levels of .beta. carotene and vitamin A in blood plasma were found in cows fed ration based mainly on maize silage. The supplementation of daily winter rations with 300 mg Rovimix-.beta. carotene per cow, beginning 14 days before parturition and 60 days after calving increased slightly the .beta. carotene and vitamin A concentrations of blood plasma and improved some fertility indices: the number of inseminations per cow was reduced and the percentage of conception rate was significantly higher. It may be assumed that .beta. carotene content in feeds and it's utilization rate generally reflected in .beta. carotene blood plasma level and in the improvement of fertility.