The elephantgrass (EG) used as grazing is primarily based on the conventional systems. The objective of this research was to evaluate the pasture quality in crude protein (CP), neutral detergent fiber (NDF) and dry matter in vitro digestibility (DMIVD), comparing distinct forage systems (agroecologic and conventional). Four paddocks, each one with 0.12ha, were used in the evaluation. In the conventional pasture, the EG was established in singular form. In agroecologic the EG plantation was in lines with a distance of 3m between lines. The mixture of oat and ryegrass in the cool-season, while spontaneous species in the warm-season have been done in the space between the lines. The fertilization was done with organic fertilizers (150kg ha-1 of N). Seven grazings were performed during the experimental period from 04/24/2004 to 05/05/2005 (375 days). Using the same amount of N (urea), four grazing cycles were performed in the conventional pasture which was evaluated for 213 days (from 10/06/2004 to 05/05/2005) on the warm-season. In both systems, Holstein cows receiving 3.5kg daily-1 complementary concentrate feed were used in the evaluation. The initial forage mass based on dry matter and pasture components was considered in the evaluation. Samples from hand-plucking method were collected to develop the qualitative analyses. The experimental design was completely randomized, with two treatments, conventional and agroecologic, two replicates (paddocks) and incomplete split plot to the time (grazings). There was interaction (P<0.05) between treatments and grazings for all parameters. At agroecologic pasture was verified cubic effect for all variables, during grazing time. In the conventional pasture, CP and DMIVD were adjusted better to the linear model, with positive growth rate, and inverse behavior were found to NDF during the grazings. In the conventional pasture as well as in agroecologic, negative associations between EG leaf lamina with CP and DMIVD and positive with NDF were found. In short, the agroecologic likewise the conventional system showed high qualitative values considering fertilization, manage and utilization time.
Avena strigosa; Lolium multiflorum; mixed pastures; Pennisetum purpureum; production systems
