Influencia de enzimas exógenas O Saccharomyces cervisiae en dietas fibrosas sobre la fermentación ruminal y producción de gas in vitro en ovinos

Abstract

The purpose of this investigation was to evaluate the effect of the exogenous enzymes or Saccharomyces cerevisiae in fibrous forages over ruminal fermentation in ovines. The experiment was carry out in the Faculty of Agricultural Sciences of the UTA. Two experiments were carried out, 1) 4 mixed-breed male animals with an average live weight of 30kg housed in metabolic cages and 2) 4 mixed-breed male ovines provided with a fistula with a cannula in the rumen (2 inches of internal diameter and 5 inches of external diameter). The animals were distribute randomly in a 4x4 Latin square design. The ovines were fed an integral diet based on barley stubble. Four treatments were evaluated; T1: control diet (without enzymes or yeasts), T2: diet with enzymes (2 mg / kg), T3: diet with yeasts (1.5 mg / kg) and T4: diet with enzymes and yeasts (2 mg / kg enzymes + 1.5 mg / kg yeast). Voluntary intake, pH, ammoniacal nitrogen production, VFAs, kinetics of ruminal degradation in situ and in vitro, gas production were determined. Voluntary nutrient intake showed no differences between treatments (P> 0.05). Voluntary consumption of digestible nutrients was higher for T1, T2 and T4. Digestibility was higher for T1, T2 and T4 in MS and MO, while for NDF and FDA it did not show differences between treatments P = (0.1035 and 0.2029). The in situ ruminal degradation of the MS was greater for T2, T3 and T4. Regarding in vitro gas and methane production, the lowest production observed was in T1, T2 and T4. Finally, the pH remained at an average of 7.3 - 7.6, which is favorable for enzymes and optimal for ruminal microorganisms; the ammonia nitrogen increased in the T2 and the production of VFAs did not show differences between treatments (P> 0.05). Under the conditions of this study it was concluded that the addition of exogenous enzymes to the diet favored food consumption, fiber digestibility, degradation and pH, thus creating an optimal environment for the development of ruminal microorganisms and therefore a better synthesis of the protein; resulting in a decrease in gas production at the rumen level.