The performance and characteristics of 18 carcasses of feedlot-finished Zebu cattle were evaluated over 93 days in confinement or semi-confinement systems. In the semi-confinement system, two strategies of pasture deferral were adopted, 40 days (40DD) and 80 days (80DD). The feed of animals in confinement was composed of 24% of grass silage Urochloa spp. and 76% concentrate, on dry matter, freely supplied twice daily. Grazing animals received 4 kg of animal concentrate per day. The final fasting weight of the animals in confinement (534.92 kg) was higher than that of animals semi-confined in 40DD (475.33 kg) and 80DD (460.67 kg) pastures, because of the higher daily weight gain (1.37 vs. 0.82 and 0.64 kg, respectively). Feedlot-finished animals had a greater carcass gain (0.91 kg animal -1 day -1 ), resulting in a higher carcass weight (296.47 kg), higher thickness of external fat (5.42 mm), weight and percentage of side cut (17.88 kg and 12.20%), and weight and percentage of fat in the carcass (74.50 kg and 25.22%). However, no difference was observed for the metric and developmental characteristics of the carcass, which allowed good quality carcasses to be obtained, independent of the strategies evaluated. Feedlotfinished Zebu cattle provide heavier and bulky carcasses, leading to higher revenue per marketed carcass. Key words: Confinement. Fat. Gain yield. Semi-confinement. Trimming. ResumoAvaliou-se o desempenho e as características da carcaça de 18 bovinos anelorados terminados durante 93 dias em confinamento ou semiconfinamento. No semiconfinamento foram adotadas duas estratégias de diferimento da pastagem, com 40 dias (40DD) e 80 dias (80DD). A ração dos animais confinados foi composta de 24% de silagem de capim Urochloa spp. e 76% de concentrado, na matéria seca, fornecida à vontade duas vezes ao dia, enquanto que os animais em pastejo receberam 4 kg de concentrado animal -1 dia -1 . O peso final em jejum dos animais confinados (534,92 kg) foi superior aos semiconfinados em pastagem 40DD (475,33 kg) e 80DD (460,67 kg), devido ao maior ganho de peso diário (1,37 vs. 0,82 e 0,64 kg, respectivamente). Animais terminados em confinamento tiveram maior ganho de carcaça (0,91

The objective of this study was to evaluate the effect of post-grazing residual leaf blades (RLB) of different lengths on the morphogenic and structural characteristics of Urochloa brizantha ‘Piatã’ grazed upon by beef cattle. A completely randomized design was used, with three RLB lengths (2, 4, and 6 cm) and two paddocks as replicates over two grazing seasons (wet and wet-dry transition). To monitor the weekly forage growth, two representative clumps and 48 tillers per treatment were marked after grazing. The procedure continued until the plants reached the target pre-grazing height of 35–40 cm. Morphogenic characteristics were not affected by the treatments or seasons, with minor changes observed in mean sheath length (MSL) within season and tiller population density (TPD). The MSL reached its peak value of 210.37 mm during the wet season relative to 175.89 mm during the wet-dry transition. The TPD reached its lowest value (680 tillers m-2) at the highest defoliation intensity (2 cm) relative to that at the lowest defoliation intensity (720 tillers m-2). The different RLB lengths modified canopy height variably; canopy height was the highest with the 6 cm leaves (24.31 cm), but did not vary between the 2 cm and 4 cm leaves. The post-grazing leaf area index and interception of photosynthetically active radiation were modified by season. The highest defoliation intensity (2 cm) increased the rest period by seven days when compared with the lowest defoliation intensity (6 cm).