The objective of this study was to verify the effect of reducing in pasture height at the beginning of the deferment period (PHBD) of Brachiaria brizantha cv. Marandu on nutrient intake and digestibility in sheep during winter. The combinations between average sward heights (15, 25, 35 and 45 cm) at the beginning of the deferment period and the times of sward use during the winter were evaluated; intake and digestibility evaluations were carried out at the beginning, middle and end of the grazing period, which lasted 90 days. The experimental design used was completely randomized, with three replications. The parameters evaluated were: intake and digestibility of dry matter (DM), crude protein (CP) and neutral detergent fiber (NDF) and potentially digestible dry matter (pDDM). The pDDM contents were similar in pastures kept with 15 and 25 cm, but higher than those observed in pastures with 35 and 45 cm at the beginning of the deferment period. The NDF contents were lower and the CP and NDF digestibility were higher in 15 and 25 cm deferred pastures than in 35 cm at the beginning of deferment period, except for pastures lowered to 45cm. The improvement in nutritional value of the forage apparently ingested by sheep, promoted by ISP reduction, did not result in a variation in pasture consumption by the animals. DMI, expressed as percentage of body weight (%BW), ranged from 1.10 to 1.63. At the beginning of the grazing period, higher values of pDDM, CP and DM digestibility (DMD) were verified in simulated grazing samples. The same response pattern observed for nutritional value traits also occurred for DMI (g.day-1 and %BW) and CP intake. These were higher at the beginning, than at the middle and end of the grazing period. The use of lower sward heights at the beginning of the deferment period allowed the production of pasture with better nutritional quality, but these changes in the nutritional value of the pasture were insufficient to result in higher nutrient intake and digestibility. Furthermore, there was a reduction in nutritional value of the forage apparently consumed by sheep, in the intake and digestibility of deferred pastures throughout the grazing period, in winter. The lower pastures at the beginning of the deferment period (15 cm) improves the nutritional value of forage and nutrient digestibility at the beginning of the winter grazing period. The nutritional value and intake of deferred forage by sheep are compromised by the grazing period.

To verify if strategies to reduce the height of Marandu grass pasture at beginning of the deferral period change intake and metabolic parameters in sheep during the dry season, 18 crossbred females, ½ Dorper + ½ Santa Inês were used, distributed in 9 Marandu grass paddock handles to 3 drawdown strategies at the beginning of deferral period: 1) maintenance of grass with 15cm for 5 months before deferral start (15/15cm); 2) maintenance of marandu grass with 25 cm for 5 months, but at the beginning of deferral it was reduced to 15cm (25/15cm); 3) maintenance of 35 cm grass for 5 months, but at the beginning of deferral it was reduced to 15cm (35/15cm). The experiment was conducted in a completely randomized design (CRD), with 6 repetitions and repeated measures over time. Strategies to reduce the height of Marandu grass pasture, at the beginning of the deferral period, do not change nutrient intake and energy and protein metabolism. However, changes occurring in the pasture during the dry season alter these variables, and deferral is an interesting strategy to be used for forage production in winter, however, to optimize its use, it is necessary to use supplementation with concentrated rich in fermentable carbohydrates.

The objective was to investigate the feeding behavior of sheep in marandu grass (Brachiaria brizantha cv. Marandu) pastures under continuous stocking with the same average height and different horizontal structures. The treatments were composed of less heterogeneous pastures (P-H, 24% coefficient of variation of plant heights and more heterogeneous pastures (P+H, 46% coefficient of variation of plant heights) and the locations of the picket, front and back, were also evaluated. A randomized block design was used, with split plots in space and four replications in two years. Crossbred lambs were used, managed under continuous stocking and variable stocking rate, to maintain average height of pastures at 30 cm. Greater masses of total forage, live leaf, live stem and dead material, and greater time of sheep in rumination, occurred in the front, in relation to the paddock background. In P-H, grazing time (GT) did not vary between regions. In P+H, GT was lower at the front than at the background. Idle time (IT) was similar between P-H and P+H. However, the animals remained more IT in the front than in the background. The feeding behavior of grazing sheep is modified in marandu grass pastures under continuous stocking with the same average height, but with different spatial variability of the vegetation.

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