0773 The effect of phase feeding on feed cost, growth, and performance of calves fed milk replacer

Abstract

Ninety-six 3- to 10-d-old Holstein bull calves with an average initial BW of 44.1 kg (SD 1.67) were shipped from Wisconsin to the Land O'Lakes Research Facility in northwest Iowa. The objective of this study was to evaluate the use of phase feeding with a milk replacer (MR) containing only milk protein in the first phase and a MR using hydrolyzed soy protein modified (HSPM) in the second phase of calf rearing. Calves were randomly assigned according to BW and blood γ globulin to one of four MR diets offered in a 15% solution: 1) 27% CP containing only milk protein, 10% fat (control); 2) phase feeding, 28% CP, 20% fat in Phase 1 and 22% CP, 15% fat with HSPM in Phase 2; 3) phase feeding, 28% CP, 20% fat in Phase 1 and 25% CP, 15% fat with HSPM in Phase 2; and 4) phase feeding, 28% CP, 20% fat in Phase 1 and 28% CP, 15% fat with HSPM in Phase 2. Calves were fed to provide 816 g DM/d during Days 1 to 6 and 1,135 g DM/d during Days 7 to 41, in 2 feedings at 0600 and 1515 h. Calves were offered 567.5 g in one feeding at 0600 h during the last week. Calf starter (22% CP, as-fed basis) was offered ad libitum throughout this 48-d trial. Data were analyzed by Mixed procedures of SAS. Total weight gain, MR consumption, feed:gain ratio, and starter intake did not differ (P > 0.05) among treatments. Total feed costs over the 7-wk trial were significantly lower (P < 0.05) for the three phase-feeding treatments. Calves on the three phase-fed diets performed equally to calves on the control-fed diets and the feed costs were significantly reduced, making this a viable option where applicable.