The use of favored or unfavored ingredients in starter feeds for preweaned calves
When calves are allowed to choose among different ingredients, soybean meal and wheat are the most consumed ingredients commonly used in starter concentrates, whereas canola and oats are among the least consumed. The objective of this study was to evaluate three different starter feeds containing ingredients of different acceptance by calves. Sixty-three (n=21) Holstein male calves (41 ± 1.3 kg BW, 9 ± 0.9 d of age) were grouped in three treatments: a starter feed (18.6% CP, 21.4% NDF) based on soybean meal (17.5%), wheat (22%) and corn (24%), a starter feed (18.1% CP, 21.5% NDF) based on canola (15%), wheat (22%) and corn (18%), and a starter feed (20.3% CP, 18.5% NDF) based on soybean meal (18.5%), oats (24%) and corn (26.5%). All starter feeds were in a pellet form, and straw was also offered ad libitum. The milk replacer feeding program was the same for all three treatments: 4 L/d at 12.5% DM concentration from 1 to 7 d of study, 6 L/d at 12.5% DM from 8 to 35 d of study, and 3 L/d at 12.5% DM from 36 to 42 d (weaning). Animals were weighed weekly until the end of the study at 49 d, and milk replacer and starter feed intake measured daily. At 30 and 50 d of study, liquid rumen samples were obtained to determine rumen pH. Data were analyzed by mixed procedure of SAS with repeated measures, being concentrate ingredients composition and week of the study, and their interaction the main effects, and initial BW as a covariate. Animals in all three treatments had similar performance and intake parameters (0.64 ± 0.045 kg DM/d of starter intake, 0.62 ± 0.027 kg/d of ADG). There were no differences in rumen pH (5.65 ± 0.084 pH) among the three treatments. In conclusion, the inclusion of a non-favored ingredient such as canola or oats in a pelleted starter feed did not affect performance parameters of preweaned calves.
Keywords: calf, ingredient composition, performance