부산대학교 도서관

Exogenous enzymes can improve domestic ruminants’ productive performance by improving the amount of nutrients obtained from their rations, mainly from the fibrous portions. Dietary inclusion of exogenous enzymes can act synergistically with endogenous enzymes from the rumen during digestion and can modify the populations of ruminal communities and methane emissions. In the present study, dietary supplementation of a multi-enzyme (M-E) complex (Optimax E[sup.®]) at 0, 0.2, 0.4, and 0.8% of dry matter (DM) increased nutrient digestibility, daily weight gain, and net energy, and improved feed conversion and the Firmicutes/Bacteroidetes ratio. Results confirm that including Optimax E[sup.®] can be used to improve lambs’ performance. The objective of this study was to evaluate the effects of increasing levels of the M-E complex (xylanase, glucanase, cellulase, and invertase) Optimax E[sup.®] on the performance of growing lambs, their digestibility, and their rumen microbiota, and to estimate NEm, NEg, and ruminal methane levels. Forty lambs (Katahdin x Dorset; 22.91 ± 4.16 kg) were randomly assigned to dietary concentrations of ME (0, 0.2, 0.4, and 0.8% DM) and fed individually for 77 days. Increasing M-E improved feed conversion (p < 0.05) as well as NEm and NEg (p < 0.05), which were associated with increased in vivo DM and NDF digestion (linear and quadratic p < 0.01). Few microbial families showed abundancy changes (Erysipelotrichaceae, Christensenellaceae, Lentisphaerae, and Clostridial Family XIII); however, the dominant phylum Bacteroidetes was linearly reduced, while Firmicutes increased (p < 0.01), resulting in a greater Firmicutes-to-Bacteroidetes ratio. Total Entodinium showed a quadratic response (p < 0.10), increasing its abundancy as the enzyme dose was augmented. The daily emission intensity of methane (per kg of DMI or AGD) was reduced linearly (p < 0.01). In conclusion, adding the M-E complex Optimax E[sup.®] to growing lambs’ diets improves their productive performance by acting synergistically with the rumen microbiota, modifying the Firmicutes-to-Bacteroidetes ratio toward more efficient fermentation, and shows the potential to reduce the intensity of greenhouse gas emissions from lambs.
Author(s): Germán David Mendoza-Martínez [1]; Pedro Abel Hernández-García (corresponding author) [2,*]; Cesar Díaz-Galván [1]; Pablo Benjamín Razo-Ortiz [2]; Juan José Ojeda-Carrasco [2]; Nalley Sánchez-López [1]; María Eugenia de la Torre-Hernández [...]