Supplementation level increasing dry matter intake of beef cattle grazing low herbage height

Abstract

To evaluate the foraging behaviour of yearling bulls grazing on Marandu grass, we conducted two experiments. In the first experiment (Exp. 1), three grazing heights of 15, 25, and 35 cm were evaluated, with bulls receiving 0.3% of body weight (BW) of supplement (161 g kg-1 crude protein (CP) and 20.1 MJ kg-1 gross energy (GE)); in the second experiment (Exp. 2), supplementation levels were decreased as grazing height increased: (1) low height (15 cm) and high supplementation (0.6% BW: 142 g kg-1 CP and 18.9 MJ kg-1 GE (LH-HS)); (2) moderate height (25 cm) and moderate supplementation (0.3% BW: 161 g kg-1 CP and 20.1 MJ kg-1 GE (MH-MS)) or (3) high height (35 cm) without supplementation (HH-WS). Ingestive behaviour was evaluated by direct visual observations, and intake using markers. It was used 9 paddocks each experiment. The experimental design was completely randomized, analysing effects by polynomial orthogonal contrasts (Exp. 1) and Tukey test (Exp. 2). In Exp. 1, a linear decreasing response to daily grazing time (P < 0.01) was observed, whereas a linear increasing response to herbage intake (P < 0.01) was observed with increased grazing height. In Exp. 2, LH-HS bulls had lower herbage intake (P < 0.01) than their counterparts. Bulls from both experiments showed increased grazing activity after 12 PM (P < 0.05). The herbage intake substitution effect of supplements can be explored as a production strategy, as the adjustment of supplementation levels can promote high dry matter intake as well as performance in beef cattle, in conditions of low grazing height or low forage allowance, even with a high stocking rate.

Advances in Pasture Management and Animal Nutrition to Optimize Beef Cattle Production in Grazing Systems

“…Pasture management under different grazing intensities promotes different responses in forage mass accumulation and nutritive value. Studies conducted at FCAV/Unesp Campus de Jaboticabal, Brazil generated consistent data on the effects of different heights of tropical pasture management in the rainy season [30,[32][33][34][35][36][37]. The afore mentioned authors evaluated Marandu grass pastures in a continuous stocking and variable stock grazing system, at three heights: 15, 25 and 35 cm.…”

Suplementação para bovinos de corte na estação chuvosa: revisão / Supplementation for beef cattle during the rainy season: a review

“…A adição de concentrado na alimentação de bovinos em pastejo possibilita maximizar a utilização dos recursos forrageiro, resultado dos efeitos nutricionais interativos entre consumo de suplemento e forragem (DETMANN et al, 2014a). Barbero et al (2020) avaliaram a redução dos níveis de suplementação a medida que a altura de pastejo aumentou: 1) pasto baixo (15 cm) e alta suplementação (0,6% PC: 142 g/kg PB e 18,9 MJ/kg energia bruta); 2) pasto moderado (25 cm) e Brazilian Journal of Animal and Environmental Research, Curitiba, v.5, n.1, p. 625-636, jan./mar. 2022. moderada suplementação (0,3% PC: 161 g/kg PB e 20,1 MJ/kg energia bruta) ou 3) pasto alto (35 cm) sem suplementação (somente mistura mineral).…”

Influences of Conventional Feeding Regimen on the Productivity of Bali Cattle in Samarinda

“…This contributed to increased feed's crude fiber contents, consequently, the forage quality was lowered. The quantity, quality, and adequacy of feed nutrients (forage) affect the productivity and efficiency of the beef cattle business (Flaten et al, 2019;Barbero et al, 2020).…”