Effects Of Ratio Of Concentrate To Roughage On Digestibility, Metabolism, Environment Of First Stomach Compartment Of Alpacas

Six alpacas(BW29.5±7.1kg,1-year old) were used in a3×3Latin square, respectively, to evaluate the effects of diets with different ratios of concentrate to roughage(C:R=3:7,5:5,7:3) on the environment in compartment I of alpacas. The results showed that:The DMI didn’t show significant difference when the diet changed. The digestibilities of DM, OM, CP, EE, CF and ADF didn’t show significant difference with different diets. When the animals were fed the diet with30%concentrate, the digestibility of NDF was higher than the diet with50%concentrate(P<0.05), higher than the diet with70%concentrate(P<0.01). The average concentration of purine derivatives of urine didn’t change a lot with the diets change(P>0.05). It is the C:R was3:7that showed a lower value of RN/DN in alpacas compared with the other2diets(P<0.01). the The pH value of C-1decreased slowly when the concentrate increased. The average concentration of NH3-N in C-1didn’t show significantly difference when the alpacas fed different diets(P>0.05). The concentration of NH3-N was highest before alpacas were fed, then decreased after they were fed, it reached the lowest6h later, then increased slowly. The results showed the concentration of acetate, propionate, total VFA, valeric acid, isovalerate were not significantly difference. When the animals were fed more concentrate, the propionate decreased, acetate, the total VFA increased slowy. When the concentrate to roughage was7:3, the acetate to propionate ratio was higher (P<0.05) than the other two diets, the isobutyrate was lower (P<0.05) than the other two diets. When the concentrate to roughage ratio was3:7, the butyrate was lower (P<0.05) than the other two diets. The MCP concentration was higher(P<0.05) when the concentrate to roughage ratio was7:3compared to3:7. The pectinase activity was higher(P<0.05) when the concentrate to roughage ratio was5:5compared to7:3. The amylase activity was lower (P<0.05) when the concentrate to roughage ratio was7:3compared to3:7. The other enzyme (urease, protease, xylanase, β-glucose glycosidase, carboxymetyl cellulose, filter paper enzyme) didn’t show significantly difference no matter which diets were fed(P>0.05). The same results showed in the number of protozoa(P>0.05). Accroding to the experiment results, the writer considered that when the alpacas were fed diet with5:5concentrate to roughage, the alpacas had a better digestibility and metabolism of forage, and also was good for the fermertation, microbial and enzyme activity.