RESUMO Este trabalho teve como objetivo avaliar o valor nutritivo e a força de cisalhamento da cultivar de Urochloa brizantha (syn Brachiaria brizantha) cv Xaraés submetida a três intensidades luminosas e quatro cortes. O experimento foi conduzido na FMVZ - Unesp de Botucatu, com delineamento experimental em blocos ao acaso, sendo os tratamentos: luminosidade natural, redução de 30% e 60% de luz, com quatro cortes e três repetições. As análises realizadas foram: composição bromatológica, digestibilidade e a força de cisalhamento. Não houve diferença na digestibilidade entre os tratamentos em nenhum dos cortes, mas a qualidade forrageira foi influenciada pelos níveis de intensidade de luz, tendo o tratamento com 60% de redução de luminosidade apresentado maiores concentrações de proteína bruta e cinzas, menores teores de fibra em detergente neutro, hemicelulose, celulose e força de cisalhamento. Em relação aos cortes estudados, o primeiro teve o menor intervalo de corte e produziu forragem com qualidade superior em comparação ao último, pois obteve menor teor de fibra em detergente ácido, lignina, hemicelulose, celulose e consequente menor força de cisalhamento. Portanto, a redução de 60% de luminosidade é benéfica à qualidade e à força de cisalhamento da cultivar Xaraés.

We aimed to evaluate the effect of the inclusion of corn and citrus pulp as additives in soybean silage made in plastic (PVC) tubes. The experimental design was completely randomized, with a 2x4 factorial arrangement consisting of two additive groups (corn and citrus pulp) and four inclusion levels (no inclusion, 7, 14 and 21%). The experiment was conducted at the Forage Sector of the Lageado Experimental Farm, Faculty of Veterinary Medicine and Animal Science, UNESP, Botucatu, SP, and chemical composition analysis was carried out at the Laboratory of Bromatology. The soybean variety used was BMX Potência RR. Mechanical harvest occurred at the R7 phenological stage, at a height of 15 cm, using a harvester equipped with a two-row platform. The material was chopped into medium particles of 3 to 6 mm. After 45 days, the silages were analyzed for dry matter, crude protein (CP), total digestible nutrients, pH, ethereal extract, neutral detergent fiber, acid detergent fiber, lignin, total dry matter loss, and total carbohydrates (CHOS). The inclusion of corn (21%) and citrus pulp (14 and 21%) reduced CP values (P<0.05). Control silage contained less CHOS (P<0.05). The inclusion of corn meal is better than citrus pulp to improve the values of soybean silage.

Agrosilvopastoral system is a type of production that involves the soil-forage-animal interface, both of which are benefited by the system. Hence, the present study evaluated the effects of agrosilvopastoral system on the quantitative and qualitative characteristics from pasture, and the animal performance during the feeding period of Nellore heifers. The treatments included: Soil-forage-animal – 357 eucalyptus trees per hectare (LFA14x2m); Soil-forage-animal – 227 eucalyptus trees per hectare (LFA22x2m); and Soil-animal – Five native trees remaining per hectare (CON). The forage used was Brachiaria brizantha cv. BRS Piatã and having as trees planted the Eucalyptus urograndis clones H 13. Treatment effects (P <0.05) for forage accumulation and pasture height, which were lowest in LFA14x2m compared to the others. Total forage dry mass in CON treatment was significantly greater (P <0.05) compared to the other treatments, showing maximum production in March. The LFA14x2m treatment was favorable for greater forage quality, showing an effect on chemical composition (P <0.05), compared to other treatments. Whereas, in November the LFA22x2m treatment was better for neutral detergent fiber. January and March, the treatments were similar (P >0.05) for average daily gain, while in November period, LFA14x2m treatment showed the lowest value (P <0.05). The lowest weight gain by area (November) occurred in the LFA14x2m treatment (P <0.05), although in March the LFA14x2m treatment stocking rate was similar to the others. Forage production and animal performance are altered by the trees densification in agrosilvopastoral systems. The chemical composition of pasture is better in systems with a higher trees density.

The aim of this study was to evaluate the chemical composition, dry matter losses and aerobic stability of aerial part silage of araruta whit inclusion of citrus pulp and validate the forage as an alternative source of food for ruminant animals. The experimental design was completely randomized factorial scheme 3x4 (inclusion levels of additive and opening times) with five replications. The inclusion of 30% of additive promoted an increase of 8.5% in the dry matter content to the exclusive silage. Fermented silage compared to the in natura material showed a decrease of the fibrous components. The inclusion of citrus pulp and silo opening times did not influence the non-fibrous carbohydrate content. However, the additive promoted increases in total carbohydrate content of silages. There was no statistical difference for effluent and gas losses. Silage only including 30% citrus pulp had the lowest dry matter recovery. The average maximum temperature reached by the silages was 34.5ºC. The average time for temperature increase was 67 hours for all silages. Aerial part silage of araruta can be used in animal feed, and is a potential forage resource for use in semiarid region.

SUMMARY This study aimed to evaluate the pasture productive and nutritional characteristics of Brachiaria brizantha cv. BRS Piatã in integrated systems with different densities of trees. Considering as plot the systems: integrated crop-livestock-forest with rows of trees (eucalyptus) spaced at 14 m and 357 trees ha-1 (ICLF-14m), ICLF with rows of trees spaced at 22 m and 227 trees ha-1 (ICLF-22m) and the integrated crop-livestock (ICL) with five remaining native trees ha-1; period of the year as subplots, and sampling points as subsubplots (A, B C, D, and E) arranged perpendicular to trees alleys. It was evaluated the production of forage and leaf blade dry mass, leaf:stem ratio, soil coverage, radiation photosynthetically active interception, canopy height, crude protein (CP), neutral detergent fiber (NDF), in vitro digestibility of organic matter (IVDOM) of the leaf blade, and stem associated with the leaf sheath. There was a significant difference (P<0.05) for all variables due to the month within the integrated systems. Mainly in January and March, showing the forage and leaf blade dry mass reduction due to a higher trees density. System with higher trees density showed the lowest soil coverage and canopy height sampling points A and E in ICLF-22m showed lower forage and leaf blade dry mass production and soil coverage. The system with higher trees density showed lower value of NDF of the leaf blade, and higher CP contents. The IVDOM of the leaf blade was higher in ICLF systems. For the evaluated parameters the best results were for the ICLF-22m.