Substituição do farelo de soja pelo farelo de algodão corrigido com uréia em dietas à base de palma forrageira para vacas em lactação

Abstract

The objective was to evaluate the effect of replacement of soybean meal by cottonseed meal on the diet of dairy cows fed diets based on spineless cactus. Five Girolando lactating cows were used, with average live weight of 490 kg and average production of 11,5 kg of milk/day, distributed in a 5x5 Latin square design (5 animals, 5 treatments and 5 experimental periods). Each experimental period lasted 15 days, 10 days being for the adaptation of the animals to the diet and 5 days for data collecting. The experimental diet was composed by spineless cactus (53%), sorghum silage (32%) and concentrate (15%). The cottonseed meal replaced 0, 25, 50, 75 and 100% of soybean meal in the concentrate. The intake, milk yield and composition were evaluated. The nutrients intake and digestibility is not affected by the treatments, with average of 15,55 and 56,05; 13,8 and 59,31; 0,37 and 49,40; 5,32 and 30,95; 1,79 and 48,14; 9,94 and 54,31; 4,43 kg/day and 80,99%,to the dry matter, organic matter, ether extract, neutral detergent fiber, crude protein, total carbohydrates and non-structural carbohydrates; respectively. The total nutrients digestible are not affected (average of 8.30 kg/day). At the same, the milk yield and composition, fat corrected milk yield(4%), lactose, total solids, fat and protein were not affected by replacement (11,56; 11,41 kg milk / day and 4,45; 12,75; 3,95 and 3,42%, respectively). We recommend the replacement of soybean meal by cottonseed meal to the low production dairy cows.