Feeding Encapsulated Methionine Supplement to Lactating Cows,,

Abstract

Twenty lactating Holstein cows were fed individually and were randomly assigned to 4 treatment groups in a continuous 120-day trial. The study was to determine the effects of methionine supplementation at 12g per day and of feeding methionine supplement more frequently than twice daily. Treatment 2× was twice daily feeding; 2×M, twice daily feeding plus methionine; 4× was 4 feedings daily, and 4×M was 4 feedings daily plus methionine. Average daily fat-corrected milk production, milk fat, milk protein, and ration intake by treatments were: 2×) 19.21kg, 3.49%, 3.56%, 16.42kg; 2×M) 18.22kg, 3.72% 3.49%, 15.59kg; 4×) 17.56kg, 3.60%, 3.41%, 15.11kg; and 4×M) 17.37kg, 3.43%, 3.47%, 13.88kg. Analysis of covariance indicated no significant differences (P < .05) for daily fat-corrected milk production, milk composition, and feed intake. No significant differences were found in urinary urea nitrogen, urine volume, urinary nitrogen, creatinine, urinary amino acids, or blood ammonia. The 4× group had higher blood urea nitrogen values than other groups. The 4× and 4×M groups appeared to have lower methionine to valine ratios than the 2× and 2×M groups at the end of the trial. Feeding encapsulated methionine at 12g per day showed no benefit for increasing fat-corrected milk production. © 1970, American Dairy Science Association. All rights reserved.