Ovinos e caprinos terminados em caatinga raleada e enriquecida com Capim buffel (Cenchrus ciliaris L.).

Abstract

The Caatinga is the vegetation of the semi-arid northeast, its native flora is made up of a food source for sheep and goats that are created often extensively; the quality and quantity of pasture available is a limiting factor for the animal production, mainly in dry season. This aspect, along with the practice of overgrazing has compromised the development of the botanical species of better nutritive value, greatly affecting its availability and supply of dry matter, resulting in a reduction of intake, digestibility and animal performance. Then, it’s necessary a management strategy for the optimize itself use, which enhances the thinning and enrichment of the Caatinga. This study was carried out at Lameirão Experimental Station/CSTR/Federal University of Campina Grande. Twenty-four animals were used, 12 crossbreed goats (Boer x SRD) and 12 Santa Inês sheep, with an initial live body weight (LW) of 15.0 kg and 220 days-old. The feeding system consisted of grazing from 8:00 to 17:00 hours, then, the animals were collected to stalls equipped with troughs and water fountains. To evaluation of dry matter the herbaceous vegetation was separated into Cenchrus ciliaris L. grass, herbaceous dicotyledonous and other grasses that have been evaluated in 5 periods. The only species that had their participation in the two treatments until the end of the experiment were Cenchrus ciliaris L. grass and Aristida setifolia, among the grasses, and Rhychosia minimum and Hyptis suaveolens, in the group of dicotyledonous. The accumulation rate of grass Cenchrus ciliaris L. not statistically different (P> 0.1) between the periods during all experiment. It was found to increase (P <0.1) on supply of Cenchrus ciliaris L. grass in areas grazed by sheep in 32.9 versus 13.3 kg GDM/100 kg BW / day in areas grazed by goats.The Dry Matter (DM) content of buffel grass (Cenchrus ciliaris L.) in the beginning (jun/01) of the experiment was lower (P <0.1) than that observed in other periods. There was variation in the performance of animal species (P <0.05), with goats showing an average daily weight gain higher than sheep, but the final weight did not change (P> 0.05). The use of sheep and goats finished in thinned Caatinga enriched with Cenchrus ciliaris L. grass favored the disappearance of botanical species of high nutritive value. Just as affected by decreasing progressively the availability, accumulation rate and supply of dry matter of herbaceous dicotyledonous.The chemical composition of herbaceous vegetation wasn’t affected by grazing animals. As the estimate of DM digestibility of herbal components, among the two methods tested, the most efficient was the iNDF method. In the thinned Caatinga enriched with buffel grass, the goats had higher intake responded with better performance compared to sheep.