Behavior of four different mixed pastures in the South Part of the State of São Paulo, Brazil. I. Botanical composition, protein and fiber content

Abstract

The grazing trial was conducted from February, 1981 to April, 1986, at the county of Itapetininga, ni the South of the State of São Paulo, Brazil, comparing the behaviour of four tropical mixed pastures under three grazing pressures (low, medium and high). The management system used was the continuous grazing one with variable stocking rates during the different parts of year. Each kind of mixed pasture was composed by three paddocks of different sizes (0.63, 0.83 and 1.25 ha) which were maintained with the same number of animals during each time. The data were analized by co-variance comparing regression lines, utilizing only one replication. It was studied seasonal variations of botanical composition as well as the crude protein contents of each species in the mixtures. The standard mixture was green panic plus perennial soybean which showed a mean of 8.44% CP and 34.76% FB. In the comparison between the standard. mixture with the other ones studied the kazungula setaria plus Galactia striata mixture showed high dry matter amount under grazing (P < 0.01) although the CP content was lower. The mixture guinea grass plus Desmodium uncinatum and rhodes grass plus Tinaroo soybean did not differ statistically from the standard mixture in neither of the parameters studied. The mixture rhodes plus Tinaroo soybean showed a good balance grass/legume and are suited to be used in the Shouth part of the State of São Paulo.