Correlação entre componentes morfológicos do pasto de Urochloa Brizantha diferido e comportamento ingestivo em ovinos

Abstract

The objective was to evaluate how different morphological components are present in Urochloa brizantha cv. Marandu carried may affect the feeding behavior of sheep in the dry period. The experiment was carried out at Capim-Branco Experimental Farm, belonging to the Faculdade de Medicina Veterinária of Universidade Federal de Uberlândia (UFU), in Uberlândia, Minas Gerais, from September 2021 to August 2022. Three treatments with three replications were used. The first treatment (LC15) consisted of keeping the pasture in a continuous stocking at a height of 15 cm for 5 months before the deferral period. The second treatment (LI 25/15) adopted the intermittent stocking rate, where the animals were placed in pastures with an initial height of 25 cm and removed at 15 cm, from November until the beginning of the deferral period (March). The third treatment (LC 35/15) adopted continuous stocking to gradually lower the height of the pasture by 5 cm per month, starting in November, until reaching 15 cm in height, at the beginning of the deferral period (March). Two adult pregnant and crossbred ewes with ½ Dorper blood and ½ Santa Inês blood were allocated in 9 paddocks, totaling 18 animals. To obtain the forage mass, the morphological components of the pasture, and the feeding behavior, two collections were carried out during the grazing period of the animals. In the evaluation of the feeding behavior of the animals, the animals were observed for 12 hours recording every 10 minutes the activity the animal was doing (grazing, rumination and idleness). The variables of feeding behavior and morphological components (live leaf, live stem, dead leaf and dead stem) were descriptively determinant using graphs to obtain models with linear responses. The same data were also statistically analyzed using Pearson's Correlation to obtain significant correlation coefficients, considering a significance level of 5%. The main conclusions were that, the morphological components alter the sheep feeding behavior, pastures with a greater dead stem and dead leaf, the animals spend more time in grazing to select forage, while pastures with a greater live leaf and live stem, animals reduce grazing time. For production quality deferred pastures and better response in the animals, strategies must be used to reduce the presence of dead stems and increase the number of live leaves.