Improved Lactational Performance in Dairy Cows Supplemented with Methionine or Rumen-Protected Choline During the Transition Period

Abstract

The current study was aimed to determine the effects of dietary supplementation with rumen-protected choline and methionine on dry matter intake, milk yield, milk composition and body condition score of transition cows. In this study, 32 Holstein dairy cows which made one parturition at least was used as the animal material. The cows were randomly assigned to four groups according to lactation number, previous lactation milk yield and body condition score before close-up. Cows within each group was fed a basal control (CON) diet (n=8). Cows in treatment group methionine (MET, n=8) were supplemented with 42 g/d of methionine (Metasmart(R)). Cows in treatment group choline (CHOL, n=8) were supplemented with 75 g/d of rumen protected choline (RPC) source (CholiPEARL (TM)). Cows in treatment group Mix (MIX, n=8) were supplemented with 75 g/d RPC and 42 g/d methionine. Milk yields and dry matter intakes were determined during the trial as daily. At the results of analyses that were detected; milk yield and composition the highest level in MET group (P<0.028). In conclusion of this study that was determined; the supplementation of methionine to the rations of dairy cows affected milk yield and composition positively.