Estratégias de suplementação para vacas de corte gestantes no período seco e suplementação de bezerros de corte lactentes com diferentes níveis de proteína

• Autor(a) principal: Lopes, Sidnei Antônio
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/5731
• topic: Creep-feeding; Desempenho; Matrizes; Creep-feeding; Desempenho; Matrizes; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::NUTRICAO E ALIMENTACAO ANIMAL::AVALIACAO DE ALIMENTOS PARA ANIMAIS

This study was based on two experiments on ratings, production and nutrition of beef cattle supplemented on pasture. The first experiment was to evaluate the effects of supplementation with infrequent replacement of soybean meal by soybean on productive performance, nutritional characteristics and microbial efficiency in beef cows pregnant in Uruchloa decumbens pastures in the dry period. Thirty five crossbred cows with predominance of zebu, with an average age of approximately six years, with initial weight and initial body condition score average of 450 ± 0.8 kg and 4.3 ± 0.2 (scale of 1 to 9), respectively. The design was completely randomized in a factorial 2 x 2 +1, and seven repetitions. The treatments evaluated were; two isoprotéicos multiple supplements, made with two protein sources (soybean meal and soybean), provided in two weekly supplmentation, daily or three times a week (Monday, Wednesday and Friday) and control receiving mineral ad libitum. The supplements were provided in the trough in the amounts set 1.0 kg / animal / day, and always 10:00 a.m.. There wasn t effect (P>0.10) the frequency of supplementation and protein source on average gain and end body weight. The intakes of DM, NDF and NFC weren t affected (P>0.10) by supplementation and infrequent protein sources. Effects were observed infrequently and sources of supplementation protein (P<0.10) on digestibility of DM and NFC. The NDF digestibility was affected (P<0.10) by protein sources. The CP digestibility was affected by infrequent supplementation (P>0.10). The infrequent supplementation and replacement of soybean meal by soybean prove to be viable alternative management system for cattle, since they allow similar results. Infrequent supplementation did not affect the intake of nutrients compared to daily supplementation. The daily supply supplements containing soybean increases the body condition score of beef cows on pasture. In the second experiment was to evaluate the effects of supplementation with different levels of crude protein on productive performance, intake and digestibility of nutrients and efficiency of microbial protein synthesis in beef suckling calves grazing pasture. Fifty five calves, with a mean age of 100 days and average weight of 110 ± 7.5 kg, and their mothers (beef cows with predominance of zebu), with initial weight and initial body condition score average of 450 ± 15 , 3.5 and 98 kg (range 1-9), respectively. The experimental design was completely randomized with five treatments and eleven replications. The calves were allocated to treatments consisting of protein levels in supplements, 8, 19, 30 and 41% CP based on natural materials. Additionally, we established a control group receiving only mineral mixture ad libitum. The supplements were daily at a rate of 0.5% of body weight of calves. The cows received only mineral mixture ad libitum. Supplemented calves had higher (P<0.10) average daily again. Protein levels showed quadratic effect (P<0.10) for average daily again. The intakes DM and DNDF, profiles were cubic (P <0.10) with the CP levels in supplements. There weren t differences between the intakes of TMD, TMO, NDF (P> 0.10). Supplementation increased (P<0.10) digestibility of nutrients, except for the digestibility of NDF. Supplementation increased (P<0.10) the production of microbial nitrogen, and N losses in urine. The use of multiple supplements containing 35% CP provides greater weight gain of animals compared to animals receiving only mineral mixture. The intakes of supplements replace part of the pasture ingested by calves, improving the digestibility of the diet.