RESUMO Objetivou-se avaliar os efeitos de quatro alturas (15, 25, 35 e 45cm) da Urochloa brizantha cv. Marandu (capim-marandu) no início do diferimento sobre a morfologia do pasto, a seletividade e o desempenho de ovinos no início, meio e fim do período de pastejo, no inverno. Foi utilizado o delineamento inteiramente ao acaso, com três repetições. Os pastos diferidos com 35 e 45cm apresentaram maiores massas de forragem do que aqueles diferidos com 15 e 25cm. O pasto diferido com 15cm apresentou maior porcentagem de folha e menor percentual de colmo morto, em comparação aos demais pastos. A seleção por folha morta aumentou no período de pastejo. Em geral, nos pastos diferidos mais altos, os percentuais de folha viva foram menores e os de colmo morto, maiores nas amostras de pastejo simulado. O desempenho dos ovinos foi superior no pasto diferido com 15cm, intermediário nos pastos diferidos com 25 e 35cm, e inferior no pasto diferido com 45cm. A manutenção do capim-marandu com 15cm no início do diferimento resulta em pasto com melhor morfologia, otimiza a seletividade e aumenta o desempenho dos ovinos no inverno.

The objective of this study was to evaluate the apparent selectivity of sheep in marandu palisadegrass (Urochloa brizantha cv. Marandu) pastures with four heights at the beginning of the deferment period (15, 25, 35 and 45cm). The deferment period was 92 days and started on 03/21/2014. Evaluations occurred in the beginning (first week), middle (45th day) and end (92nd day) of the grazing period, in winter (06/21/2014 to 09/21/2014). Deferred pastures with 15 and 25cm presented lower forage mass (FM), but higher live leaf (LL) percentage in FM than deferred pastures with 35 and 45cm. The live stem percentage in the FM and the apparent selectivity index (ASI) of the LL were superior in the deferred pasture with 45cm. The dead stem (DS) percentage in the grazing simulation (GS) and the ASI of this morphological component were lower in the pasture with 15cm, compared to the deferred pasture with 45cm. The FM and the LL percentages in FM and in the GS sample decreased, while the DS percentages in FM and in GS sample increased with the grazing period. Marandu palisadegrass with 15cm at beginning of the deferment period improves the morphology of the deferred pasture. Selective grazing is difficult during the grazing period.

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This study aimed to assess the effects of yellow grease supplementation on the intake, digestibility, and nitrogen balance in sheep. Twenty Santa Inês lambs with a mean age of 95 ± 10 d and body weight of 19.29 ± 3.17kg were evaluated in a completely randomized design. The diets were supplemented with oil at concentrations of 0, 20, 40, 60, and 80 gkg-1 of dry matter (DM) of the concentrate. The diets were based on roughage and concentrate (50:50). The experimental period lasted 19 d and included 14 adaptation days and five collection days for the total supplied diet, orts, feces, and urine. Supplementation with yellow grease had no significant effect on the intake of DM, crude protein (CP), neutral detergent fiber (NDF), or non-fiber carbohydrates (NFC). However, the ether extract (EE) intake increased linearly with supplementation of yellow grease. Moreover, no effect was observed for DM, CP, NDF, and NFC digestibility and nitrogen balance. EE digestibility increased linearly with the yellow grease dietary supplementation. Thus, sheep dietary supplementation with yellow grease may be used at a level of up to 80 gkg-1 of DM of concentrate without impairing nutrient intake and digestibility.