The effects were assessed of substituting half the total diet protein in solid form (soybean meal) with liquid form (soybean milk) at solid:liquid ratios of: 100.0:0% L; 87.5:12.5% L; 75.0:25.0% L. Twenty-four Holstein breed 60-d male calf steers were assigned to a randomized block design, with three concentrate (80%) diets and 20% coast-cross (Cynodon dactylon) hay, balanced for nitrogen and energy. In the diets with liquid parts, the intention was to keep the functional reflex of the esophageal groove throughout the 10 months of the experimental period, in which the animals were kept in a feedlot until slaughter at body weights higher than 400 kg. In some of the animals, with rumen canulas, only small quantities of ingested soybean milk were detected in the rumen contents, indicating success in esophageal groove formation. Daily weight gains were linearly reduced (1.399, 1.341 and 1.191 kg) as the treatments supplied larger quantities of soybean milk. Dry matter and crude protein conversions in weight gains, in the last 60 days of the experimental period, declined as the proportions of liquid feed increased. Supplying protein in liquid form in the diet did not alter carcass yield in Holstein steer.
dairy cattle; early slaughter; esophageal groove; feed conversion; liquid feeding; weight gain
