Using climatic variables to estimate dry matter production in the grazing stratum of Piatã palisadegrass

Abstract

The modeling of pasture production could be used as a tool to make the process of working with increasingly erratic precipitation and temperature patterns resulting from climate change easier and more accurate. This study aimed to define models to determine dry matter, leaf and stem production associated with climatic variables for Palisadegrass (Brachiaria brizantha cv. Piatã) in the grazing stratum. Four treatments were established to provide the greatest variability throughout the experiment, consisting of two light interception percentages as cutting criteria (95 and 100%) and two residue heights (15 and 20 cm). Data were collected between January 2012 and December 2013. Dry matter production day À1 (DMPd), leaf production day À1 (LPd) and stem production day À1 (SPd) were regressed against 13 climatic variables. The variables were also corrected by multiplying each variable by the relationship: real evapotranspiration/potential evapotranspiration. The backward procedure was used to determine significant variables to estimate production; then a multiple regression was fitted. When the corrected variables presented better Akaike's Information Criterion (AIC), they replaced the original variables. The analysis showed that climate variables are adequate to estimate DMPd, LPd and SPd in palisadegrass cv. Piatã, and the models should significantly contribute to pasture management across tropical regions.

Effect of protein supplement level on the productive and reproductive parameters of replacement heifers managed in intensive grazing systems

“…The composition and availability of the grazing stratum was estimated between d 6 and d 9 through two isolation cages (1.0 × 1.5 m), in the same way used by [ 12 ]. The forage inside the cage was cut/sampled at the same height of the pasture consumed by the animals [ 12 , 34 ]. At the end of each digestibility trial, samples of pasture and feces were pooled and stored at −20 ºC.…”

“…the cage was cut/sampled at the same height of the pasture consumed by the animals [12,34]. At the end of each digestibility trial, samples of pasture and feces were pooled and stored at −20 ºC.…”

Intake, performance, and feeding behavior of Holstein and Holstein x Gyr heifers grazing intensive managed tropical grasses during the rainy season

“…The grazing stratum composition and availability were determined using two isolation cages (1.0 × 1.5 m) placed in the paddocks before the animals' entrance (from d-16 to d-18), in a location representing the height and density of pasture. On the day following the animals' removal from the paddock, forage samples were taken from the cage by cutting the stratum at the same height as the pasture intake (Brandao et al, 2018).…”