TY - JOUR ID - 23541 TI - Effect of Supplementation of Different Level Protein Diets with Rumen Protected Methionine and Lysine on Performance and Ruminal Parameters of Holstein Dairy Cows in Early Lactation JO - Iranian Journal of animal Science JA - IJAS LA - en SN - 2008-4773 AU - Abdi Benmar, Hossein AU - Rezayazdi, Kamran AU - Dehghan banadaki, Mehdi AD - Y1 - 2011 PY - 2011 VL - 42 IS - 3 SP - 221 EP - 230 KW - Crude protein level KW - lactating cow KW - Milk production and composition KW - Rumen protected methionine and lysine KW - Ruminal parameters. DO - N2 - The objective of this study was to evaluate the effects of supplementation of different level protein diets with rumen protected methionine and lysine on performance and ruminal parameters in Holstein dairy cows when in their early lactation. Twenty one dairy cows in their early lactations were assigned to three treatments in a randomized block design experiment of a 35-d duration period. Diets were: 1) High protein diet containing 17.5% crude protein (CP), 2) Moderate protein diet bearing 16% CP along with 12 gr/d of rumen protected methionine, 3) Low protein diet with 14.5% CP plus 14 gr/d of rumen protected methionine and also 5 gr/d of rumen protected lysine. Dry matter intake, milk production, 3.5% fat corrected milk (3.5% FCM), percent content of milk fat, molar concentration of rumen volatile fatty acids and ruminal fluid pH were not significantly affected by diets. However, experimental treatments significantly affected percent of milk protein, milk urea nitrogen and ruminal ammonia concentration (P UR - https://ijas.ut.ac.ir/article_23541.html L1 - https://ijas.ut.ac.ir/article_23541_20cf4f392ea5434ebb91546d7246a32f.pdf ER -