Desempenho de gramíneas tropicais no semiárido

Abstract

The aim of this thesis was to evaluate the performance of Andropogon grasses (Andropogon gayanus Kunth), Buffel (Cenchrus ciliary L.) cv. Grass and Massai (Panicum maximum x Panicum infestum) at ages 21, 35, 49 and 63 days. The experiments were carried out at the Federal Institute of Education, Science and Technology of Rio Grande do Norte - IFRN Campus Apodi, in the period from June to December 2014. The evaluations were carried out in two stages, which yielded three scientific papers. In the first stage, information was addressed regarding the forage species, which were emphasized morphogenetic and structural characteristics and the production and chemical composition of corn in different regrowth ages. In the second stage, it was shown the evaluation of animal performance using hay of the three studied forages, which analyzed the nutrient intake, feeding behavior and sheep performance. For morphogenic and structural evaluation the andropogon presented late vegetative development, contrary to the development presented by buffel grass. Grasses Andropogon, Buffel and Massai increase the production of dry matter with advancing age of regrowth, the andropogon showed higher growth rates of dry matter (469.41%). It occurred only difference between the grasses and Andropogon Massai, from 49 days of regrowth. The crude protein, neutral detergent fiber and lignin components were more varied with increasing regrowth period in all forage species. In assessing the performance of animals fed with hay, it was observed that the regrowth ages influenced rumination, reducing its efficiency with advancing age. The daily weight gain of the animals fed the massaigrass hay and grass Andropogon hay did not differ, but differed from the buffel grass hay. The daily weight gain was not influenced by the age of grasses. Overall analysis showed that the thesis information interrelation helped to determine the best way to choose the forage species to the region, reaching the conclusion that in the conditions, the Massai and Andropogon grasses stood by vegetative best performance and best responses to animals.