Suplementação de bezerras de corte lactentes com diferentes níveis de proteína bruta e características nutricionais e produtivas de vacas de corte

• Ano de defesa: 2012
• Autor(a) principal: Cardenas, Javier Enrique Garcés
• Orientador(a): Paulino, Mário Fonseca
• Banca de defesa: Rennó, Luciana Navajas , Marcondes, Marcos Inácio , Chizzotti, Mario Luiz
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Zootecnia
• Departamento: Genética e Melhoramento de Animais Domésticos; Nutrição e Alimentação Animal; Pastagens e Forragicul
• País: BR
• Palavras-chave em Português: Bezerras de corte; Forragem; Suplementação
• Palavras-chave em Inglês: Beef heifers; Forage; Supplementation
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::NUTRICAO E ALIMENTACAO ANIMAL
• Link de acesso: http://locus.ufv.br/handle/123456789/5773

The objective of this investigation was based on an experiment related to animal production and nutritional evaluations of calves and their mothers which were kept on pasture. Calves were supplemented with creep-feeding techniques. The experiment was aimed to assess the efficacy of supplementation of heifers calves with different levels of crude protein and assess the nutritional characteristics and production of beef cows. 60 heifer calves were used; predominantly Nelore blood, aged between 126 ± 3,08 days, and an average initial weight of 123 ± 3,09 kg. Their mothers with initial weight and body condition score of 450 ± 6,97 kg and 3,7 ± 0,07, respectively. The experimental design was completely randomized with six treatments and ten repetitions. Treatments for heifer calves were different levels of protein levels in supplements of 7.3, 16.7, 25.6, 34.6 and 43.2% crude protein on dry matter basis, and the control group receiving only mineral mix ad libitum. The supplements were fed daily at a rate of 0.5 kilogram per heifer. The cows received only mineral mix ad libitum. Supplemented heifers had higher average daily gain in the control group (P <0.10) and no difference was observed between the different supplemented groups. There were no differences (P> 0.10) in total dry matter intake and milk dry matter. The control group had a higher dry matter intake from pasture (P <0.10). The apparent digestibility of dry matter, lipids, carbohydrates, fiber, neutral detergent fiber corrected for ash and protein, and total digestible nutrients did not differ for any of the treatments (P> 0.10). Effects were observed (P <0.10) on the urinary excretion of urea nitrogen g / day. And a linear profile for increasing levels of crude protein supplementation was observed. There were no effect (P> 0.10) levels for supplementation on the flow of microbial nitrogen compounds in g / day. There was no effect (P> 0.10) in microbial efficiency expressed as g microbial crude protein /kg of total digestible nutrients consumed, and the flow of microbial nitrogen compounds in relation to nitrogen intake (g/g) of nitrogen intake showed negative linear profiles. Treatments did not affect daily microbial production (P> 0.10). The concentration of serum urea nitrogen was higher in animals that received some type of supplement on compared to non-supplemented animals (P <0.10). This fact can be attributed to higher crude protein intake. There weren´t any significant differences (P>0,10) between the last weight, average daily gains, body condition score and the milk production of the cows as soon as the treatments of the calves. It is concluded that multiple supplementation increments the average daily gains of nursing calves. There was no detectable effect of the supplement composition, in terms of protein concentration. The feeding of 0,5 kg/day of multiple supplements to nursing calves doesn´t influence the average daily gains of weight, body condition score and the production of milk from the cows.