Cinética de fermentação ruminal de dietas com coprodutos da cadeia produtiva do biodiesel

Abstract

The objective of the present work was to determine the effect of increasing levels of coproduct (sunflower crushed and crambe crushed) in diets fed to ruminants (cattle and sheep) on in vitro dry matter digestibility (IVDMD), organic matter (IVDOM), crude protein (IVDCP), the kinetics of cumulative gas production, ruminal fermentation parameters, concentration of ammonia-N (NH3- N) and pH in vitro. Two diets were used for the experiment with sunflower crushed, and, in the experimental diet 1: characterized by the presence of Brachiaria brizantha marandu as roughage and concentrates that had different proportions of sunflower crushed being; 0 g/kg, 200 g/kg, 400 g/kg and 600 g/kg in partial replacement of soybean meal in a roughage concentrate 60 : 40. The experimental diet 2, Tiflon used hay as roughage and concentrates were characterized by the presence of 0 g/kg, 100 g/kg, 200 g/kg and 300 g/kg inclusion of sunflower crushed in the concentrate, the concentrate roughage used was 50 : 50. As in the experiment with sunflower crushed, crushed in working with crambe used two diets, whereas the experimental diet 1 : characterized by the presence of Brachiaria brizantha marandu as roughage and concentrates that had different proportions of crambe crushed being; 0 g/kg, 50 g/kg, 100 g/kg and 150 g/kg replacement of soybean meal in a roughage concentrate 40 : 60. The experimental diet 2 : used corn silage as roughage and concentrates were characterized by the presence of 0 g/kg, 50 g/kg, 100 g/kg and 150 g/kg inclusion crambe crushed to replace soybean meal in the concentrate to roughage concentrate adopted was 30 : 70. The methodology used to perform the incubations, collection and analysis of working with sunflower crushed was the same used for crambe crushed, and follow the following rules: The coefficients of IVDMD, ammonia-N (NH3-N) and ruminal pH, cumulative gas production and ruminal fermentation kinetic parameters were determined using ruminal and Buffer. To determine the total gas production and ruminal fermentation, ruminal technique was used automatic in vitro. The increased pressure inside the bottles produced during the incubation was measured in pounds per square inch (psi) using automatic RF: Gas Production System ® (ANKOM). Was performed in an adaptation covers glass jars used to simulate the conditions of the rumen in a digstibilidade in vitro, and can thus determine the concentration of ammonia-N and the pH of the rumen fluid. The fit of the curves and the parameter estimates of biological interest were performed using the iterative Gauss-Newton through the procedure for non-linear models program SAEG. The IVDMD and IVDOM quadratic effect for two experiments with sunflower crushed in experiment 1 was the peak for the diet with 200 g/kg of sunflower crushed, in experiment 2 the maximum point of IVDMD was for the diet with 200 g/kg and IVDOM the diet with 0 g/kg showed the maximum point of digestibility. The kinetic parameters of experiment 1 showed no different quadratic effect in Experiment 2 where C (hours), d (mL/gas), E (/ h) parameters showed a quadratic effect. In experiments with crambe crushed observed quadratic effect for IVDOM of experiment 1, with the diet of 150 g/kg with the maximum 139 point. In experiment 2, there was a quadratic effect on IVDMD and IVDOM being the maximum point of the diet with 0 g/kg The use of experimental diet 1 with sunflower crushed, reduced the in vitro digestibility of dry matter and organic matter, and increased crude protein, did not affect the kinetic parameters, reduced pH and increased ammonia-N. In two experimental diet with sunflower crushed, exhibited reduced digestibility of DM and OM as well as the experimental diet 1, but did not affect the digestibility of crude protein, restricted gas production resulting from the degradation of the fiber fraction and reduced parameters pH and ammonia-N. The crambe crushed is a coproduct with a good profile of ruminal fermentation kinetics with respect to the degradation of non-fiber carbohydrates and fibrous carbohydrates, and potential suppliers of energy and protein in the diet of ruminants. Replacement of soybean meal with crambe crushed elicited a reduction in digestibility of dry matter, organic matter and crude protein, however, this reduction does not prevent it from being used in up to 150 g/kg substitution of soybean meal. The use of diets with partial replacement and inclusion of sunflower crushed in the concentrate reduced the in vitro digestibility of dry matter and organic matter, and increased crude protein, restricted gas production coming from the degradation of the fiber fraction, reduced the pH and increased ammonia-N.