Resumo -O objetivo deste trabalho foi avaliar os efeitos de níveis de inclusão de glicerina bruta (GB), contendo 36,20% de glicerol, na dieta de cordeiros em terminação, sobre o consumo, digestibilidade dos componentes da dieta e desempenho produtivo e econômico. Utilizaram-se 35 cordeiros machos não castrados da raça Santa Inês, com peso médio inicial de 20±2,27 kg, distribuídos em delineamento inteiramente casualizado, com cinco tratamentos e seis repetições. Os tratamentos consistiram de níveis de inclusão da GB na dieta (0, 3, 6, 9 e 12% da matéria seca), em substituição ao milho. Após 10 dias de adaptação, cinco animais foram abatidos para se obter o rendimento de carcaça inicial. Após o período de adaptação, os 30 animais restantes foram alojados em baias individuais. Quando o grupo atingiu o peso médio de 35 kg, os animais foram abatidos. Houve efeito linear decrescente dos níveis de GB sobre o consumo de MS e ganho médio diário de peso, e efeito quadrático sobre o coeficiente de digestibilidade da fibra em detergente neutro corrigida para cinzas e proteínas. Houve efeito quadrático também sobre o peso corporal final dos animais e conversão alimentar (CA). A GB contendo 36,20% de glicerol pode ser incluída na dieta de cordeiros em terminação em até 6% da MS da dieta, com otimização da CA e aumento dos benefícios econômicos.Termos para indexação: biodiesel, coprodutos, desempenho, glicerol, ovinos, ruminantes. Crude glycerin on finishing lamb dietsAbstract -The objective of this work was to evaluate the effects of crude glycerin (CG) inclusion, with 36.20% of glicerol, on finishing lamb diets on intake, nutrients digestibility, and productive and economical performance. Thirty-five intact male lambs (Santa Inês), with 20±2.27 kg of initial average body weight were randomly assigned to five treatments, with six replicates. The treatments consisted of increasing crude glycerin levels on the diet: 0, 3, 6, 9 and 12% of diet dry matter. After ten days of adaptation, five animals were slaughtered to determine initial carcass dressing. After the adaptation period, 30 animals were housed in individual pens. When the group reached average body weight of 35 kg, animals were slaughtered. The CG levels had a negative linear effect on dry matter intake and average daily weight gain, and a quadratic effect on neutral fiber detergent digestibility corrected for ash and protein. Crude glycerin levels had also a quadratic effect on body weight at slaughter and feed-to-gain ratio (FGR). Crude glycerin with 36.20% of glycerol can be included in the diet of finishing lambs up to 6% of dry matter, optimizing the FGR and promoting economic benefits.Index terms: biodiesel, co-products, performance, glycerol, sheep, ruminants. IntroduçãoA terminação de cordeiros em confinamento é uma prática que tem despertado o interesse de produtores, por possibilitar a redução das perdas de animais jovens decorrente de deficiências nutricionais e infestações parasitárias. Além disso, essa prática permite a regularidade de oferta da carne dura...

Thirty non-castrated male lambs with 20±2.3 kg average body weight (BW) were randomly assigned to five treatments consisted of different dietary concentrations of crude glycerin (CG; 0, 3, 6, 9 and 12% on DM basis) to evaluate the effects on performance, carcass and meat quality traits. A quadratic effect was observed for performance (P=0.04), final BW (P<0.01) and hot carcass weight (P<0.01). No effects of CG were observed (P>0.05) on carcass pH neither on shear-force, cooking loss and ether extract content in longissimus. The inclusion of CG tended to reduce the Zn content in meat (P=0.09). The data suggests that CG (36.2% of glycerol and 46.5% of crude fat) may be used in diets of finishing lambs with concentrations up to 3% without negative effects on performance and main carcass traits. Moreover, inclusion of CG seems to not affect quality and safety of meat for human consumption.

Our objective was to estimate the energy and protein requirements of Holstein young calves up to 87 days old. Forty-two Holstein calves aged 4 days were used. From these, ten were randomly selected and slaughtered to compose the baseline slaughter (BS) group. The remaining calves were randomly assigned to eight treatments in a 4 × 2 factorial using a completely randomized design. The treatments were 2, 4, 6, and 8 kg/day of milk (297 g/kg CP; 319 g/kg of fat) fed twice daily, and then harvested at 59 or 87 days of age. Calves were fed a starter (193 g/kg CP; 133 g/kg NDF) ad libitum in all treatments. The calves slaughtered at 87 days of age had milk replaced by Coast-cross (Cynodoon sp.) hay (125 g/kg CP; 728 g/kg NDF). The net requirement of energy for maintenance (NEm) was 0.36 MJ/kg EBWG, with efficiency of utilization of energy for maintenance (k m) of 59.4 %. The equation obtained to estimate the net requirement of energy for gain (NEg; MJ/d) was 4.40 × EBW(0.099), with the efficiency of utilization of energy for gain (k g) equal to 46.5 %. The observed requirements of net and metabolizable protein for maintenance (NPm and MPm) were 3.67 and 3.88 g/kg BW(0.75), respectively. The efficiency of use of metabolizable protein for maintenance (k pm ) was 94.6 %. The predicted requirements were higher than those observed in the literature, and this study demonstrated that the requirements of newborn calves are higher than the recommended.

-The objective of this study was to evaluate the in situ and in vitro degradation kinetics and to predict the digestible neutral detergent fiber (dNDF) from the incubation times; in situ and in vitro degradation kinetic parameters; and equations fitted for agricultural and agro-industrial byproducts. Byproducts from pineapple, cocoa, palm kernel, corn gluten meal, common bean, sunflower, guava, cassava bark, cassava stems, cassava foliage, papaya, mango, passion fruit and turnips were evaluated. There were differences between the byproducts as for the potentially neutral detergent fiber (NDF) fraction and the in situ NDF degradation rate in the final volume of the gases generated by fibrous carbohydrates (FC), for the lag time and for the in vitro fractional degradation rate of the FC. There was equivalence between the dNDF values predicted in situ and those observed in vivo; however, there was low precision of estimates. The degradability in the in vitro incubation times of 30 and 48 hours presented equivalence with the values observed, but also did not present precision in the estimates. The equations fitted without lignin were not precise and accurate to estimate the dNDF of agricultural and agro-industrial byproducts.The equation with lignin and with the digestion rate obtained by the in vitro method presented more precise estimates.Byproducts from common bean, cassava bark and papaya presented greater NDF availability, whereas those of guava had the lowest NDF availability. The digestible NDF fraction was best predicted with the in situ incubation time of 72 hours. The equation fitted utilizing in vitro or in situ digestion rates enables the prediction of the NDF availability of agricultural and agroindustrial byproducts.

The objective of this work was to quantify the net requirements for the maintenance (NRm) and growth (NRg), as well as the retention coefficient (RC) of calcium, phosphorus, sodium, potassium and magnesium, of Holstein calves. The NRm were 87.8, 20.8, 4.36, 2.21, and 1.01 mg kg-1 of empty body weight for Ca, P, Na, K, and Mg, respectively. The RC was 0.882, 0.473, 0.274, 0.088, and 0.052 for Ca, P, Na, K, and Mg respectively. The requirements of Ca and P of Holstein calves are higher than those estimated for adult animals.