Effects of supplamental niacin, choline and biotin on some milk and blood parameters in dairy cattle during transition period

Fourty two heads of Holstein transition (from 3 weeks before to 3 weeks after parturition) dairy cows thwere used as the study material. The effects of supplamentation of Rumen protected choline (CL), Rumen protected niacin (N), biotin (B) and their combinations (biotin+choline BCL, niacin+choline NCL, biotin+niacin BN) into the transition dairy cow rations on blood total protein, urea-nitrogen (BUN), cholesterol, low dansity lipid (LDL), high dansity lipid (HDL), very low dansity lipid (VLDL), glucose, trigliserites, non esterified fatty acids (NEFA), betahydroxibutiric acid (BHBA) levels as well as milk yield and composition (fat,protein and lactose percentage) were examined in this study. In this respect, blood samples were taken once per week from all animals during the whole transition period while milk samples were taken once per week after parturition.Significant differences were determined in Total Protein levels at some weeks bu the total results didn?t indicate a significant diffirences for the transition period during the whole study. BUN levels remained at the referance interwals during the whole study and no significant change was occured during the whole sutdy. During parturition cholesterol levels were declined to the lowest level in all groups except the BCL group. Similarly LDL concentration was declined in all groups except N and NCL groups, VLDL and trigliserit concentrations were declined in all groups (p<0,05). On the other hand NEFA concentration was increased in all groups (p<0,05). HDL levels showed a higher course during the postpartum period compared to the prepartum period in all groups except the BCL and NCL groups. BHBA levels were significantly (p<0,05) increased during the first week in postpartum period in all groups except control and NCL groups.No significant effect was determined during the whole transition period by the supplementation of these vitamins and their combinations into the ration of dairy cows. However the differences occured in some groups during some weeks reminds that detailed studies are required to draw better conclusions.