Effect of Coleus amboinicus plant extracts in ruminant ration on microbial activity and in vitro degradation

This study was conducted to compare the use of water and ethanol as solvents to extract Coleus amboinicus L. (CAL) plant and their effect on rumen fermentation and digestion in vitro. The experimental design was a 2 × 4 × 4 Factorial arrangement in Complete Random Design. The main effects were extraction solvent (water and ethanol 96%) and levels of CAL extract (0%, 2%, 4% and 6% of amount of sample incubated). The results showed that the addition of CAL extract either extracted with water or ethanol provides an ideal pH value for rumen microbial activity (6.35-6.87). The use of water as a solvent for extracting CAL plant provides a lower concentration of ammonia and protozoa population as compared to using ethanol as a solvent. The VFA values, especially acetate, butyrate and all degradation parameters were higher in water solvent. Increasing the level of use of CAL extract to 6% tends to increase the population of protozoa and reduce the concentration of acetate and all degradation parameters except for the concentration of propionate, butyrate and total VFA which did not respond to increasing CAL levels of the extract. It could be concluded that the water solvent gives better results on the fermentation and degradation of feed with a limit of 2% usage in ruminant ration.