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Resumo -O objetivo deste trabalho foi avaliar a influência de grãos de soja (GS) no desempenho, características e rendimento de cortes de carcaça de cordeiros confinados. Sessenta e quatro cordeiros Santa Inês, com peso vivo inicial de 19,5±0,19 kg e 75±2 dias de idade, foram distribuídos em blocos ao acaso de acordo com o peso vivo e a idade no início do experimento. Os GS participaram com 0, 7, 14 e 21% na matéria seca (MS) das rações isonitrogenadas experimentais. O consumo de MS (1,1, 1,0, 0,9 e 0,9 kg por dia), proteína bruta (199,2, 181,5, 179,0 e 175,2 g por dia) e o ganho de peso vivo (298, 275, 280 e 255 g por dia) diminuíram linearmente, e o consumo de extrato etéreo (43,8, 49,7, 57,2 e 66,0 g por dia) aumentou linearmente com o aumento da participação de GS nas rações. Não houve efeito na conversão alimentar, características e rendimento de cortes da carcaça. A inclusão de GS na ração com alto teor de concentrado proporciona desempenho satisfatório aos cordeiros em confinamento.Termos para indexação: confinamento, gordura, Santa Inês, ovino. Performance and carcass characteristics of feedlot lambs fed raw soybeanAbstract -The objective of this work was to evaluate the effects of raw soybean on lamb performance, carcass yield and lamb cuts. Raw soybean was added at 0, 7, 14 and 21% of the diet dry matter (isonitrogenous). Sixtyfour Santa Inês lambs (initial body weight 19.5±0.19 kg and 75±2 days old) were assigned to a complete randomized block design according to body weight and age at beginning of the trial. Dry matter intake (1.1, 1.0, 0.9 and 0.9 kg per day), crude protein intake (199.2, 181.5, 179.0 and 175.2 g per day) and average daily gain (298, 275, 280, 255 g per day) decreased linearly, and ether extract intake (43.8, 49.7, 57.2 and 66.0 g per day) increased linearly, as levels of raw soybean increased. Feed conversion, carcass yield and lamb cuts were not affected by raw soybean inclusion in the diet. The inclusion of raw soybean in high concentrate diets provides satisfactory feedlot lamb performance.Index terms: feedlot, fat, Santa Inês, sheep. IntroduçãoO rebanho nacional de ovinos é de aproximadamente 15 milhões de cabeças, representando 1,4% do efetivo mundial, e concentra-se nas regiões Sul (30%) e Nordeste (58%) (Brasil, 2006). A produção de carne é uma atividade alternativa, capaz de aumentar a renda nos negócios, não só de ovinocultores, mas de toda a atividade rural.Apesar de a população brasileira não ter o hábito de consumir carne ovina, observa-se aumento do consumo nos últimos anos. O consumo per capita de carnes no Brasil é da ordem de 65 kg por ano; o consumo de carne de ovinos é de 0,7 kg por ano (Couto, 2001), valor considerado subestimado, já que a maior parte do comércio de carne ovina é informal.Ao se considerar o elevado custo da terra, principalmente na Região Sudeste, o confinamento é uma estratégia capaz de satisfazer tanto o produtor quanto o consumidor, uma vez que permite reduzir o ciclo de produção e disponibilizar ao mercado carcaças de animais jovens e, conse...

RESUMO -Objetivou-se avaliar os efeitos do fornecimento de polpa cítrica na dieta sobre as características de carcaça e a qualidade da carne de cordeiros em confinamento. Utilizaram-se 32 cordeiros Santa Inês distribuídos em delineamento de blocos completos casualizados com quatro tratamentos e oito repetições, os quais foram definidos pelo peso e pela idade dos animais no início do experimento de desempenho. Os animais foram alimentados com rações contendo 90% de concentrado (milho moído e/ou polpa cítrica, farelo de soja e minerais) e 10% de feno de coastcross

The objective of this experiment was to evaluate the effects of replacing coastcross hay NDF by soybean hull (SH) NDF on the lactation performance and eating behavior of ewes and also on the performance of their lambs. Fifty-six Santa Inês lactating ewes (56.1 +/- 6.8 kg of initial BW; mean +/- SD) were penned individually and used in a randomized complete block design with 14 blocks and 4 treatments. Diets were formulated to provide similar concentrations of NDF (56%) and CP (16%). The SH NDF replaced 33 (SH33), 67 (SH67), or 100% (SH100) of the NDF contributed by coastcross hay in a 70% forage-based diet (SH0), resulting in SH inclusion rates of 0, 25, 54, and 85% of the dietary DM. Once a week, from the second to the eighth week of lactation (weaning time), ewes were separated from their lambs, stimulated by a 6-IU i.v. oxytocin injection, and hand milked to empty the udder. After 3 h, milk production was obtained after the same procedure. Quadratic effect for milk production (142.4, 179.8, 212.6, and 202.9 g/3 h) and cubic effect for DMI (2.27, 2.69, 3.25, and 3.00 kg/d) were observed as SH inclusion increased from 0 to 85% of the dietary DM. Milk fat (7.59, 7.86, 7.59, and 7.74%), protein (4.53, 4.43, 4.40, and 4.55%), and total solids (18.24, 18.54, 18.39, and 18.64%) did not differ among the 70% forage-based diet and diets with SH NDF replacing 33, 67, or 100% of the NDF. A linear increase in lactose concentration was observed with SH inclusion. Ewe BW gain during the trial showed a cubic response (0.37, 0.03, 4.80, and 2.80 kg) with SH inclusion. The preweaning ADG of lambs increased linearly, and ADG of lambs after weaning decreased linearly with SH inclusion. Final BW of lambs (2 wk after weaning) did not differ among treatments. Eating behavior observations were conducted with 44 ewes. The same facilities, experimental design, dietary treatments, and feeding management were used. Observations were visually recorded every 5 min for a 24-h period when ewes were 46 +/- 6.8 d in milk. Eating time (min/d, min/g of DMI, and min/g of NDF intake) and time expended in rumination and chewing activities (min/g of DMI and min/g of NDF intake) decreased linearly with the addition of SH in the diets. The inclusion of SH improved DMI and milk production, also reflecting on the BW of lambs at weaning. Milk performance was not affected when SH NDF replaced 100% of hay NDF.

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Poor-quality roughages are widely used as fiber sources in concentrate-based diets for ruminants. Because roughage quality is associated with the efficiency of energy use in forage-based diets, the objective of this study was to determine whether differing the roughage source in concentrate-based diets could change the energy requirements of growing lambs. Eighty-four 1/2 Dorper × 1/2 Santa Inês ram lambs (18.0 ± 3.3 kg BW) were individually penned and divided into 2 groups according to primary source of dietary roughage: low-quality roughage (LQR; sugarcane bagasse) or medium-quality roughage (MQR; coastcross hay). Diets were formulated to be isonitrogenous (2.6% N) and to meet 20% of physically effective NDF. After a 10-d ad libitum adaptation period, 7 lambs from each group were randomly selected and slaughtered (baseline). Twenty-one lambs in each diet group were fed ad libitum and slaughtered at 25, 35, or 45 kg BW. The remaining 28 lambs (14 from each diet group) were submitted to 1 of 2 levels of feed restriction: 70% or 50% of the ad libitum intake. Retentions of body fat, N, and energy were determined. Additionally, 6 ram lambs (44.3 ± 5.6 kg BW) were kept in metabolic cages and used in a 6 × 6 Latin square experiment designed to establish the ME content of the 2 diets at the 3 levels of DM intake. There was no effect of intake level on diet ME content, but it was greater in the diet with LQR than in the diet with MQR (3.18 vs. 2.94 Mcal/kg, respectively; P < 0.01). Lambs fed the diet with LQR had greater body fat (g/kg of empty BW) and energy concentrations (kcal/kg of empty BW) because of a larger visceral fat deposition (P < 0.05). Using a low-quality roughage as a primary source of forage in a concentrate-based diet for growing lambs did not change NEm and the efficiency of ME use for maintenance, which averaged 71.6 kcal/kg(0.75) of shrunk BW and 0.63, respectively. On the other hand, the greater nonfibrous carbohydrate content of the diet with LQR resulted in a 17% better efficiency of ME use for gain (P < 0.01), which was associated with a greater partial efficiency of energy retention as fat (P < 0.01). This increased nutritional efficiency, however, should be viewed with caution because it is related to visceral fat deposition, a nonedible tissue.

RESUMO -Dois experimentos foram realizados para avaliar o valor nutritivo, a estabilidade aeróbia de silagens de cana-de-açúcar e a digestibilidade aparente de rações contendo essas silagens. No experimento 1, a cana-de-açúcar foi ensilada sem aditivo ou inoculada com cepas NCIMB 40788 do Lactobacillus buchneri (5 x 10 4 ufc/g de matéria verde). Amostras das silagens foram analisadas e comparadas à cana-de-açúcar in natura para avaliação da estabilidade aeróbia, considerando os dados de temperatura, pH e perdas de MS das silagens. No experimento 2, utilizaram-se 12 cordeiros distribuídos em blocos completos casualizados e mantidos em gaiolas para ensaio de metabolismo recebendo rações contendo cana-de-açúcar in natura, silagem de cana-de-açúcar sem aditivo ou silagem de cana-de-açúcar tratada com Lactobacillus buchneri. Os teores de matéria seca, carboidratos solúveis e ácido acético foram maiores na silagem com aditivo. O teor de etanol não diferiu entre as silagens. A silagem tratada com aditivo apresentou menor perda de matéria seca e manutenção do pH durante o período de avaliação em aerobiose. A digestibilidade aparente de fibra em detergente neutro, fibra em detergente ácido e hemicelulose foram maiores nas rações contendo silagem de cana-de-açúcar. Palavras-chave: ácido acético, bactérias heterofermentativas, composição química, digestibilidade aparente, etanolEffect of Lactobacillus buchneri on fermentation, aerobic stability, and nutritive value of sugar cane silage ABSTRACT -Two trials were performed to evaluate the nutritive value and aerobic stability of sugar cane silage, as well as apparent digestibility of diets containing these silages. In trial 1, sugar cane was ensiled without additive or inoculated with strains NCIMB 40788 of Lactobacillus buchneri (5 x 10 4 cfu/g wet basis). Silages were sampled, analyzed, and compared with fresh sugar cane. Aerobic stability was evaluated by controlling the temperature, pH, and dry matter losses of the silages. In trial 2, twelve lambs were assigned to a complete randomized block design and placed in metabolism crates and fed with diets composed by fresh sugar cane, sugar cane silage without additive, or sugar cane silage treated with Lactobacillus buchneri. Dry matter, soluble carbohydrates, and acetic acid concentrations were higher for silage treated with Lactobacillus buchneri when compared with silage without additive. There was no difference on ethanol levels between silages. Sugar cane silage treated with Lactobacillus buchneri showed lower dry matter losses, unchanged pH, and greater aerobic stability. Neutral detergent fiber, acid detergent fiber, and hemicellulose apparent digestibility were higher for sugar cane silage treatments.Key Words: acetic acid, apparent digestibility, chemical composition, ethanol, heterofermentative bacteria IntroduçãoAtualmente, a conservação de cana-de-açúcar na forma de silagem tem despertado o interesse de pesquisadores e produtores, sobretudo em virtude dos benefícios em logística e operacionalidade desta técnica.De...