Evaluation serum level of ß-carotene and vitamin A in new borned Holstein calves

The aim of the present study is determine the concentration of vitamin A and β- caroten in the serum of pregnant Holstein cows and calves during the birth and after the consumption of colostrum (24, 48, 72 hours after birth). This study was done to make a comparison between the level of serum vitamin A and β-caroten in dams with her calf, The blood samples were taken from 40 pregnant cows and borne calves of them, in the time of birth and 24, 48 and 72 hours after parturition. After separated serums, vitamin A and Beta- carotene were measured by spectrophotometer and using N. Hexane method. Statistically, the mean values of serum vitamin A in calves were higher than to those for dams (p<0/05), whereas the mean values of serum β-caroten in calves were lower than to those of their mothers pre and post calving. Also the mean values of serum vitamin A in females calves were more than to those in males, whereas, there was not a significant statistic differences between the mean values of serum β-caroten for males and females (p>0/05). This result shows that colostrum is necessary for cattle in the first time of birth to catch necessary substance especially vitamin A precursor.