Authors : A. Toghdory, T. Ghoorchi, A. Naserian, Y.J. Ahangari and S. Hassani
Abstract: Eight multiparous Holstein cows with an average milk production of 34.6±2.8 kg day-1 and body weight of 676±79 kg were used to evaluate the effect of rumen protected and unprotected choline on energy-related biochemical metabolites of lactating dairy cows. The experimental design was a balanced change over design with 4 treatments and 4 periods of 21 days. Experimental treatments were: No Choline (NC), Unprotected Choline (UC) fed at 50 g day-1, Rumen Protected Choline (RPC 25) fed at 25 g day-1 and Rumen Protected Choline (RPC 50) fed at 50 g day-1. Rumen protected choline was blended with 0.25 kg of ground corn and fed once per day as a top dress. Blood samples from coccygeal vessels were collected on last day of each period and analyzed for glucose, triglyceride, cholesterol, blood urea nitrogen, very low density lipoprotein, low density lipoprotein and high density lipoprotein. The result shows that blood metabolites such as glucose, triglyceride, cholesterol, blood urea nitrogen, very low density lipoprotein and low density lipoprotein not affected by treatments (p>0.05). Blood glucose concentration tendency increased by rumen protected and unprotected choline, but wasn’t statistically significant. Unprotected choline decreased concentration of high density lipoprotein than control group (p<0.05). Rumen protected choline had no significant effect on high density lipoprotein levels. High density lipoprotein decreased by using unprotected choline, but other blood metabolites not changed by treatments.
A. Toghdory, T. Ghoorchi, A. Naserian, Y.J. Ahangari and S. Hassani, 2009. Effects of Rumen Protected and Unprotected Choline on Energy-Related Biochemical Metabolites of Lactating Dairy Cows. Journal of Animal and Veterinary Advances, 8: 2181-2185.