In order to evaluate the effect of adding triglyceride to diet on rumen microbial protein production and fermentation characteristics of adult small tail ewes, two experiments were conducted in vitro and in vivo

In vitro test: the basal diet (based on dry matter) with triglyceride concentrations of 0, 2, 4, 6 and 8g / kg was used as the substrate, and the rumen juice of Adult Small Tailed ewes was added, and incubated at 39 ℃ for 48h in vitro.

In vivo test: 45 adult ewes were randomly divided into 5 groups according to their initial weight (55 ± 5 kg). Glyceryl tributylate of 0, 2, 4, 6 and 8 g/kg (based on dry matter) was added to the basic diet, and rumen fluid and urine were collected for 18 days.

Test Result

1).  Effect on pH value and volatile fatty acid concentration

The results showed that the pH value of the culture medium decreased linearly and the concentrations of total volatile fatty acids (TVFA), acetic acid, butyric acid and branched chain volatile fatty acids (BCVFA) increased linearly when tributyl glyceride was added to the substrate.The results of the in vivo test showed that the dry matter intake (DMI) and pH value decreased, and the concentrations of TVFA, acetic acid, propionic acid, butyric acid and BCVFA increased linearly with the addition of tributyl glyceride.The results of the in vivo test showed that the dry matter intake (DMI) and pH value decreased, and the concentrations of TVFA, acetic acid, propionic acid, butyric acid and BCVFA increased linearly with the addition of tributyl glyceride.

The results of the in vivo test showed that the dry matter intake (DMI) and pH value decreased, and the concentrations of TVFA, acetic acid, propionic acid, butyric acid and BCVFA increased linearly with the addition of tributyl glyceride.

2). Improve the degradation rate of nutrients

The apparent degradation rate of DM, CP, NDF and ADF increased linearly when tributyl glyceride was added to the substrate in vitro.

3). Improve the activity of cellulose degrading enzyme

The addition of tributyrin in vitro linearly increased the activities of xylanase, carboxymethyl cellulase and microcrystalline cellulase. In vivo experiments showed that triglyceride linearly increased the activities of xylanase and carboxymethyl cellulase.

4). Improve microbial protein production

In vivo tests showed that tributyrin linearly increased the daily amount of allantoin, uric acid and absorbed microbial purine in urine, and increased the synthesis of rumen microbial nitrogen.

Conclusion

Tributyrin improved the synthesis of rumen microbial protein, the content of total volatile fatty acids and the activity of cellulose degrading enzymes, and promoted the degradation and utilization of dry matter, crude protein, neutral detergent fiber and acid detergent fiber in the diet.

It indicates that triglyceride has a positive effect on the yield and fermentation of rumen microbial protein, and may have a positive impact on the production performance of adult ewes.