Produtividade e qualidade nutricional do capim piatã fertirrigado com água residuária de suínos

Abstract

Swine production in Brazil grew 38.9% in this decade, inherent the process, the pollution potential has increased, and its fate brings with it environmental concerns. In this context, the work was conducted at the Experimental Farm of Agricultural Sciences of the Federal University of Grande Dourados, in Dourados - MS, from March 21, 2014 to March 20, 2015, with the objective of evaluating the responses of Piatã grass (Urochloa Brizantha cv. BRS Piatã) at different doses of swine wastewater (SWW), in the presence and absence of irrigation, determining the variables total forage dry matter (TFP) productivity, dry matter yield of leaves and stems (YLS) , Crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and in vitro dry matter digestibility (DMD). The experimental design was randomized blocks with subdivided plots with and without irrigation in the plots, and four doses of SW subplots: 75, 150, 225 and 300 m3 ha-1 cut-1, with four replications. There was a significant effect for doses, with increasing curve, reaching mean TFP at the dose of 300 m3 ha-1 of 41.92 Mg ha-1. The results showed that the use of the highest dose of SWW together with irrigation yielded the best results of TFP and YLS with 47.8 and 41.9 Mg ha-1 year-1, respectively. Irrigation also yielded the best results per cycle, with spring promoting the highest forage accumulation of 12.28 and 8.55 Mg ha-1, irrigated and non-irrigated, respectively. In the bromatological parameters, irrigation obtained the highest average levels of CP, ADF and DMD of 16.7, 33.8 and 66.5%, respectively. NDF did not respond to irrigation and SWW doses. The research allowed concluding that the use of irrigation with fertilization with SWW brought quantitative and qualitative benefits to Piatã grass production.