Estimación de la calidad de la dieta en sistemas silvopastoriles mediante la cuantificación del nitrógeno fecal

Abstract

In order to evaluate the quality of the diet consumed by bovines in multiestrata silvopastoral systems (SSP) through estimation fecal nitrogen´s (NF), were compared four silvopastoral arrangements with variation in their vegetal composition versus a treeless prairie (M. maximum). Each arrangement was composed by shrubs (L. leucocephala y C. cujete), trees (A. saman, G. ulmifolia y C. grandis) and timbers species (P. quinata y S. macrophylla). Four cow Romosinuano x Holstein x Cebu (436±64,2 kg) were assigned in each treatment. In each cow feces were collected directly from the rectum. The samples were dried and analyzed for nitrogen (total, soluble and insoluble in NDF), NDF and the organic matter. The information obtained in NF was used for estimated the fecal crude protein (FCP), crude protein (CP) and digestibility in intake of each SSP. The NF presented as FCP was affected by treatment (p<0.1). The treatment Pasto-Arbust-Arbor-Mad showed the higher value (132.19 g.kg MO-1) significantly different from treatment Pasto, Pasto-Arbust y Pasto-Arbor, with 119.77, 116.77 y 118.91 g.kg MO-1 respectively. MO, NDF and the soluble and insoluble nitrogen no showed statistical difference between treatments. The intake digestibility and CP estimated through NF ranged from 61.45% to 65.24% and from 10.28 to 12.02 respectively. NF quantification allowed to show the quality of intake in the complex plant structure of the silvopastoral systems.