Efecto de enzimas fibrolíticas exógenas en dietas altas en fibra sobre la función ruminal in vivo e in vitro en ovinos

Abstract

The objective of this work was to evaluate the effect of the addition of fibrolytic enzymes in high fiber diets on ruminal function in vivo and in vitro in sheep. The work was carried out in the Granja Experimental Docente Querochaca. Four castrated male sheep with an average weight of 30 kg were fed a diet covering the nutritional requirements of the animals according to the 1993 AFRC, with different inclusion levels of enzymes (0%, 0.08%, 0.16% and 0.24% ). The investigation included four periods of 14 days of adaptation and 4 days of sampling for the treatments T1, T2, T3 and T4, resulting in a field work of 72 days where each animal was confined in its metabolic cage. The voluntary intake of MS and MO was higher (P <0.05) respectively, in T1, T3 and T4 with respect to the other treatment. PC consumption was higher (P = 0.0013) for T4 (363.8 g / animal / day). With respect to NDF and ADF consumption, it was higher (P <0.05) for T1 and T4 respectively (Table 3). The voluntary consumption by PV0.75 of MS, MO, NDF and FDA showed no differences (P> 0.05) between the treatments. The intake of digestible nutrients of MO and NDF showed a better response in T1, T3 and T4 respectively (Table 3). The digestibility of the FDA was higher (P = 0.0407) in the treatments with ascending levels of enzymes (linear P = 0.0060) (Table 3). The ruminal pH and the production of AGVs, acetic, butyric, isobutyric and isovaleric acids, no differences were observed (P> 0.05) between treatments, whereas propionic acid was higher (P = 00.0084) in T3 and T4 as the dose of exogenous fibrolytic enzymes. In the same way, the ratio decreased from acetate to propionate (P <0.05) in T3 and T4. A lower PG (P <0.05) was recorded in the T1 and T4 treatments than the other treatments. The kinetics of gas production (PG) (ml / 0.5g MS degraded), recorded a lower PG (P <0.05) in the treatments T1 and T4 than the other treatments. The ammonia production was higher (P = 0.0001) (table 4) in the treatments T3 and T4 with respect to the other treatments. The production of methane (Table 6) (ml / 0.5g MS fermentable) showed (P <0.05) a lower production of methane in the T4 treatment.