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Carcass characteristic and meat quality from bulls and Nellore steers (n = 64 total) subjected to different grazing heights (15, 25, 35, and 45 cm) were evaluated isolatedly, under continuous grazing and variable load, in pastures of Convert grass. The experimental period was from May 2015 to June 2017, in an area of 16 ha, divided into 16 paddocks of 1 ha. The experimental design was randomized blocks with four replications. Each paddock was grazed by three animals and regulators, used to adjust grazing heights. The final slaughter weight, hot carcass, and crude protein in the meat of steers were higher when the pastures were managed at 42 cm. When the pasture was managed between 25 and 35 cm in height, greater fat thickness, marbling, muscle:bone and muscle+fat:bone ratio and lower color* of the meat and percentage of bone were found. For the steers, the height of 40 cm provided higher fat thickness and marbling in the meat. The loss during thawing in meat was greater at 28 cm in height. The heights of grazing alter the carcass characteristics and meat of bulls and steers.

We assessed the impact of genetic divergence and the ability to combine corn hybrids used for the production of silage on the agronomic and bromatological traits of silage quality. We evaluated 18 corn hybrids used as genitors in a circulant diallel scheme in which each genitor hybrid participated in 9 hybrid combinations, and evaluated 100 treatments [18 genitor hybrids, 81 diallelic hybrids, and a commercial check hybrid (DKB330)] in a triple lattice 10 x 10 experimental design in two environments in Brazil. Genetic variability was adequate among the corn silage hybrids, and we can recommend the use of genitors 2B688 and P30B39 for the formation of a base population for intrapopulational breeding. The P30P34 hybrid is the best for intrapopulational breeding when aiming for silage with high protein content, low fiber content, and higher in vitro digestibility. Interpopulational breeding directed at improving silage digestibility can use a combination of genitors P30P34 and AS1572, but AS1572 and P30K64 are the most recommended. Hybrids 2B688, P30P34, and SG6015 are considered the most genetically distant of the others hybrids, and have desirable combining potential; therefore, they are important genitors for the formation of new segregated populations for improving corn silage.

The aim of the present study was to evaluate the different supplementation strategies for finishing Nellore beef cattle on pastures of Tanzania guinea grass (Panicum maximum Jacq. 'Tanzania'). The experiment was performed in a 12 ha area divided into 12 paddocks of 1 ha each. Forty-eight, 2-year-old, non-castrated Nellore cattle with an initial body weight (BW) of 384 kg (SEM = 21) were used in this study. The following supplementation strategies were evaluated: (1) mineral supplement supplied once per week (MS), (2) energy and protein supplement with intake regulator (2 g/kg BW) supplied once per week (EPS1), (3) energy and protein supplement (7 g/kg BW) supplied daily (EPS2), and (4) energy and protein supplement (7 g/kg BW) supplied three times per week (EPS3). The average daily gain (ADG) of animals receiving EPS3 was 0.177 kg/day higher than those receiving EPS1 (p < 0.01), 0.233 kg/day higher than the MS group, and not significantly different from EPS2. Animals in MS and EPS1 groups exhibited the lowest ADG. The ADG was not significantly different between EPS1 and EPS2 animals, but was 0.203 kg/day higher for EPS2 animals than for MS. Animals receiving only mineral supplementation spent more time grazing than the other supplementation groups tested (p < 0.01). We therefore conclude that Tanzania guinea grass is nutritionally limited and can be amended using supplements, thereby increasing animal performance. Animal performance was higher with increased protein and energy supplementation (7 g/kg BW), independent of the frequency with which supplements were administered.