INTAKE, DIGESTIBILITY, AND FEEDING BEHAVIOR OF HEIFERS FED ALTERNATIVE PROTEIN SOURCES

We hypothesize that the substitution of up to 20% of the protein source does not affect feed intake, digestibility, or feeding behavior in dairy heifers. Twenty 15-month-old dairy heifers were allocated to one of four dietary treatments in a completely randomized design. Experimental diets consisted of a corn-soybean meal-based concentrate (control); inclusion of 20% cottonseed cake on a dry matter basis; inclusion of 20% sunflower meal on a dry matter basis; and inclusion of 20% castor cake on a dry matter basis. Dry matter intake and feeding behavior of the heifers were not affected by diets containing protein sources. Likewise, nutrient digestibility was not affected by the treatments. Based on the analyzed nutritional parameters, the alternative protein sources-cottonseed cake, sunflower meal, or castor cake-can be included up to 20% of diet dry matter without affecting feed intake, digestibility, or feeding behavior of dairy heifers.