Citrus pulp-based supplement reduces the detrimental effects of high grazing pressure on the performance of beef cattle under a rotational system of Urochloa brizantha

Abstract

SUMMARY The objectives were to evaluate the performance of bull calves under two grazing strategies and the use of energy supplementation in a rotational system of marandu palisade grass (Urochloa brizantha) and to assess the morphological and chemical composition of the grass. Eighty eight-month-old bulls of 224 ± 2.4 kg body weight (BW) were used in a completely randomized block design in a 2×2 factorial arrangement of two post-grazing heights (i.e.10 cm or 15 cm) and of a citrus pulp-based supplement (i.e. 72% total digestible nutrients) fed daily at 0 or 6 g/kg BW. Initial grazing height was set at 25 cm with variable grazing intervals and stocking rate adjustments used to control the grazing heights. Statistical analyses were performed using the SAS Mixed procedure. Significance was set at 0.05. Forage data from 12 pre-determined paddocks showed no differences in forage mass (FM) and morphological composition at pre-grazing, but greater post-grazing FM and shorter grazing interval in pastures managed at 15 cm. Higher grazing pressure resulted in lowest BW gains for non-supplemented bulls in the 10 cm treatment. The use of an energy supplement and 15 cm postgrazing height resulted in the greatest BW gains; however, combination of10 cm post-grazing height and energy supplementation allowed greater stocking rates. Under high grazing pressure, supplementary feed overcame the normal limitations, and high gains were achieved.

Citrus Pulp Replacing Corn in the Supplement Decreased Fibre Digestibility with No Impacts on Performance of Cattle Grazing Marandu Palisade Grass in the Wet-Dry Transition Period

“…In the current study, animals supplemented at 0.5% LW gained in average 0.76 kg per day, similar to the liveweight performance of growing bulls under a rotational grazing system observed by Costa et al [ 1 ], using the same supplement allowance and management based on sward heights of 25 cm at the start and 10 cm post-grazing. Based on the equations of Marcondes et al [ 32 ], grazing Nellore bulls of 350 kg of LW with a DM intake of 2.2% of LW and consuming about 4.75 kg TDN/day would have an ADG of 1.0 kg.…”

“…In this context, the utilization of by-products such as citrus pulp replacing corn, an ingredient heavily utilised in human nutrition, represents an important factor in increasing sustainability on the intensification of ruminant production systems. Costa et al [ 1 ] found that a citrus pulp-based supplement helped animals maintain performance under high grazing pressure in a rotational system of Urochloa brizantha during the wet season, whilst in the current experiments, corn and citrus pulp-based supplements were used in the transition period, when both quality and amount of forage produced decrease.…”

“…This can be explained by the lower quality of the pastures in the transition period, which inhibits energy intake despite the high forage allowance; the high stem and dead material proportions most likely affected DM intake. In the work of Costa et al [ 1 ], differences in forage allowance resulted in approximately 0.1 kg difference in ADG between animals in two treatments fed the same supplement at 0.5% LW. Ground corn fed at 0.0%, 0.3%, 0.6%, and 0.9% LW to growing beef cattle under a rotational grazing system of Marandu palisade grass resulted in linear increases in ADG, stocking rates and in gain per hectare, or the amount of beef produced per area [ 3 ].…”

“…Beef cattle production in the tropics and subtropics presents unique challenges to producers across the globe. Much attention has been given to the wet [ 1 ] and drier months of the year [ 2 ] simply because there is a clear distinction in quantity as well as the quality of forage produced in these contrasting seasons. However, the transition periods may be equally important with specific limitations on forage variables that can compromise animal performance and productivity.…”

Effect of mineral-energy supplementation on the performance of young bulls from different genetic groups on pasture

“…In the rainy season, there is a range of responses regarding animal performance with the use of supplementation, as in this period the feasibility of this technique depends on the balance between the supplement characteristics and nutrients available in the pasture, controlled by grazing management strategies, which can define the level of performance of animals (Costa et al, 2019;Ziemniczak et al, 2020).…”