Objetivou-se avaliar os efeitos da inclusão de ureia de liberação lenta em substituição à ureia convencional na dieta sobre as características de carcaça de ovinos confinados. Foram utilizados 20 ovinos Santa Inês x SRD, machos não castrados, com peso corporal inicial de 21,1±1,2 kg e idade média de 120 dias, distribuídos nos tratamentos na forma de delineamento inteiramente casualizado. Os níveis de substituição utilizados como tratamentos foram 0; 20; 40; 60 e 80%, compondo dietas de aproximadamente 12% de proteína bruta, com 50% de feno de capim tifton-85 e 50% de concentrado. Não houve influência da ureia de liberação lenta sobre o peso corporal ao abate (35,17 kg) e os pesos de carcaça quente (16,75 kg) e fria (16,24 kg), entretanto, os rendimentos dessas carcaças apresentaram comportamento quadrático, revelando menores percentuais aos níveis de substituição de 48,5 e 47,63%, respectivamente. Os pesos e rendimentos dos cortes não variaram, exceto para o braço posterior, cujos valores apresentaram comportamento cúbico. As medidas objetivas da carcaça, área de olho de lombo, e as avaliações subjetivas de conformação, acabamento e marmoreio das carcaças não foram influenciadas. A espessura de gordura subcutânea decresceu de forma linear (4,25 a 2,48 mm). A inclusão de ureia de liberação lenta na dieta altera os rendimentos e reduz a gordura subcutânea, contudo, não influencia nas demais características da carcaça.

This study aimed to evaluate the effects of adding slow-release urea to replace conventional urea in the diet on carcass characteristics of feedlot sheep. We used 20 Santa Ines x SRD rams, with average body weight of 21.1±1.2 kg and average age of 120 days, distributed in a completely randomized design with 5 treatments. The replacement levels used as treatments were 0, 20, 40, 60, and 80%, composing diets of about 12% crude protein, with 50 % Tifton-85 hay and 50% concentrate. There was no influence of slow release urea on weight at slaughter (35.17 kg), and on hot (16.75 kg) and cold (16.24 kg) carcass weight, but the yield of these carcasses showed quadratic trend, revealing lower percentages at 48.5 and 47.63% replacement levels, respectively. The weights and yields of cuts did not change, except for the posterior arm, whose values showed a cubic trend. Objective measures of carcass, loin eye area, and subjective evaluations of conformation, finishing and marbling of carcasses were not affected. The subcutaneous fat thickness decreased linearly (4.25 to 2.48 mm). The inclusion of slow release urea in the diet changes the yield and reduces subcutaneous fat, however, it does not influence other carcass characteristics.

The objective of this study was to establish a correlation between the content of total lipids, cholesterol and fatty acid profile of the edible portion of the shoulders of 12 castrated and 12 non-castrated Santa Ines lambs, slaughtered at different ages (84, 168, 210, 252 days). Shoulders and the edible portion (muscle and fat) were weighed and stored at -5 °C. Castrated and uncastrated lambs increased their body weight and half carcass weight, respectively. The shoulder weight increased in the carcasses of uncastrated animals. The edible portion of the shoulders of castrated lamb has greater amount of total lipids (16.09 g/100 g). The cholesterol content was influenced by castration, reducing with age. Santa Ines castrated lambs, under semi-extensive conditions, presented larger amounts of C18:1 T11 and CLA in the edible portion of the shoulder. Castration causes no significant correlation between total lipids, cholesterol and total saturated and unsaturated fatty acids of the edible portion of Santa Ines shoulder lambs from 84 to 252 days of age.

Objetivou-se avaliar a degradabilidade ruminal da matéria seca, da proteína bruta e da fibra em detergente neutro da silagem de capim elefante com diferentes componentes de algaroba. Utilizou-se o delineamento inteiramente casualizado, com 4 tratamentos e 12 repetições, sendo as silagens: 100% de capim elefante; 70% de capim elefante + 30% de farelo de algaroba integral; 70% de capim elefante + 30% de vagem de algaroba; 70% de capim elefante + 30% de amido de algaroba. O capim elefante foi cortado com 100 dias após a rebrota, triturado e ensilado com os componentes de algaroba. Após 60 dias, os silos foram abertos e as amostras foram coletadas para a pré-secagem, moagem e posteriores análises e incubação. Amostras de cada silagem foram incubadas no rúmen de três novilhos Gir X Holandês, por períodos de 0; 3; 6; 12; 24; 48; 72; 96; 120 e 144 horas. Para o conjunto de parâmetros de degradação estudado, observou-se que os diferentes componentes de algaroba na silagem de capim elefante aumentaram a degradabilidade potencial e efetiva, a degradabilidade ruminal da matéria seca e proteína bruta. A maior degradabilidade foi observada na silagem com amido de algaroba. A algaroba e seus componentes constituem uma alternativa viável a ser adicionada na silagem de capim elefante, contudo, o amido de algaroba é mais eficiente.

The objective was to evaluate the degradability of dry matter, crude protein and neutral detergent fiber of elephant grass silage with different components of mesquite. It was used a completely randomized design with twelve treatments and four replications, and silages: 100% elephant grass, elephant grass 70% + 30% bran full mesquite, 70% of elephant grass + 30% pods mesquite, 70% of elephant grass + 30% starch mesquite. The elephant grass was cut to 100 days after sprouting, and ensiled with crushed mesquite components. After 60 days, the silos were opened and samples were collected for pre-drying, grinding and subsequent analysis and incubation. Samples of each silage were incubated in the rumen of three steers Holstein X Gir for periods of 0, 3, 6, 12, 24, 48, 72, 96, 120 and 144 hours. For the set of degradation parameters studied, it was observed that the different components of mesquite in the elephant grass silage increased the potential degradability and effectively increases the degradability of dry matter and crude protein. The higher degradability was observed in mesquite starch silage. The mesquite and its components constitute a viable alternative to be added in the elephant grass silage, however, mesquite starch is more efficient.