Levedura seca de cana-de-açúcar para fêmeas leiteiras

• Autor(a) principal: Franco, Márcia de Oliveira
• Data de Publicação: 2011
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/5692
• topic: Novilhas leiteiras; Recria de fêmeas leiteiras; Co-produtos do alcool; Dairy heifers; Recreates female dairy; Co-products of alcohol; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA::NUTRICAO E ALIMENTACAO ANIMAL::AVALIACAO DE ALIMENTOS PARA ANIMAIS

The objective was to evaluate the effect of replacing soybean meal by dried yeast of cane sugar in the diet of dairy heifers on intake and total apparent digestibility of nutrients, performance, nitrogen balance, microbial protein production and to study models to predict weight. Were used 24 Holstein dairy heifers, purebred and crossbred with initial weight of 178 kg, distributed in a completely randomized design with four treatments and six repetitions. Were used four isonitrogenous diets consisting of increasing levels of substitution of soybean meal by yeast dry cane sugar with corn silage as roughage. There was no significant difference (P>0.05) for the consumption of dry matter (DM) in kg/day and % of body weight, DM of forage in kg/day, organic matter (OM) in kg/day, crude protein (CP) in kg/day, ether extract (EE) in kg/day, neutral detergent fiber (NDF) in kg/day and % of BW, no fiber carbohydrates (NFC) in kg/day and total digestible nutrients (TDN) in kg/day, however there was an increase (P<0.05) of concentrate consumption in kg/day with increasing inclusion level of yeast in the diet. There was no difference (P> 0.05) for digestibility coefficients of DM, OM, CP, EE, NDF and TDN observed according to the levels of inclusion, but the digestibility of NFC suffered a decrease (P<0,05). There was no significant difference in body length (BL) in cm/day, rump height (RH) in cm/day and chest width (CW) in cm/day. Weight gain (WG) in kg, average daily gain (ADG) in kg/day, heart girth (HG) in cm/day and rump height (RH) in cm/day experienced a linear increase (P<0.05). Weight gain in relation to the body growth was not significantly different (P>0.05) for measurements of HG, BL, RH, WH, RW and CW in kg/cm. There was no significant difference (P>0.05) for urea in the urine (UUR) in mg/dL, plasma urea nitrogen (PUN) in mg/dL, microbial nitrogen (Nmic) in g/day and microbial efficiency (Emic) g CP/kg TDN. Prediction equations of body weight based on linear measurements proposed by Heinrichs et al. (1992) and Reis et al. (2008), were not efficient in predicting the weight of growing dairy females, however, the equations proposed by Reis et al. (2008) approximate the observed values more accurately than models by Heinrichs et al. (1992). Heart girth proved to be the best body measure correlated with the body weight observed. Thus, dry yeast can then replace soybean meal without bringing deleterious effects on production of dairy heifers in the process of growth and prediction equations of body weight should be used with caution.