Effect of Yeast Culture, Fatty Acids, Whey, and a Peptide Source on Dairy Calf Performance

The objective of this study was to evaluate different ingredients in calf starters. In the first experiment, the starter treatments were a control, sweet dried whey, a source of peptides, yeast culture, and a blend of fatty acids (butyrate, medium-chain fatty acids, and linolenic acid). In the second experiment, the starter treatments were a control and yeast culture. Holstein calves, initially less than 1-wk old, were fed 0.45 kg milk replacer powder (20% CP, 20% fat) daily for 42 d and weaned. Starters contained primarily corn and soybean meal formulated to 18% CP and were fed ad libitum. Calves were maintained in individual pens for a 56-d period. The first trial was analyzed as a randomized complete block design. In Exp. 2, a 56- to 84-d feeding period was added at the end, with calves grouped in pens of 6, and results were analyzed as a completely randomized design. When compared with control calves in Exp. 1, calves fed the peptide source had lower ADG, starter intake, and hip width change from 0 to 56 d; calves fed whey had greater feed efficiency from 42 to 56 d; calves fed yeast culture had greater ADG and feed efficiency from 42 to 56 d; and calves fed the fatty acid blend had greater ADG and hip width change from 0 to 56 d. There were no differences between treatments in Exp. 2. Results are consistent with published research. The major positive response was when the blend of fatty acids was added.