Calculating herbage utilization and intake by dairy cows under subtropical conditions using conventional field measurement techniques or the HerbValo method

LETICIA WLODARSKI; RÉMY DELAGARDE; CLAUDIO A. POZO; HENRIQUE M. N. RIBEIRO FILHO; LARISSA B.TEMP; MATHEUS LEHNHART; MATEUS G. SANTOS; GILBERTO V. KOZLOSKI

TROPICAL ANIMAL HEALTH AND PRODUCTION

SPRINGER

Lugar: Berlin; Año: 2024

0049-4747

This study aimed to evaluate the HerbValo method in comparison to conventional feld measurement techniques as a tool for estimating the herbage utilization and dry matter (DM) intake by grazing dairy cows under subtropical conditions. It was carried out during 18 months in a commercial farm of Southern Brazil. The herbage utilization was estimated monthly in two to four randomly selected paddocks (total n = 40) using the rising-plate meter or the double-sampling technique. In parallel, the herbage utilization was estimated by the HerbValo method, which is based on simple descriptions of the herd, supplements, pasture and grazing management. Values of herbage utilization estimated by feld techniques were linearly (P< 0.01) related to those estimated by HerbValo, with no efect of pasture type (tropical vs. temperate) on the origin or on the slope of the regression (slope = 0.97; origin = -0.1; R2 = 0.81; rsd = 0.17 t DM/ha). At cow × day level, values of herbage intake estimated by feld techniques were also linearly related to those estimated by HerbValo (P < 0.01; R2 = 0.82; rsd = 1.30 kg DM/cow/day). A negative linear relationship (P < 0.01) between herbage and supplement intake was obtained for both feld (slope = -1.06; R2 = 0.72; rsd = 1.64) and HerbValo (slope = -0.92; R2 = 0.82; rsd = 1.08) approaches. Herbage utilization and intake by a dairy herd in a subtropical grazing-based system can be reliably estimated by the HerbValo method with the advantage of not requiring direct feld pasture measurements.