Effects of cleavers (galium aparine) and yarrow (achillea millefolium) extracts on rumen microbial fermentation in in-vitro semi- continuous culture system (rusitec)

Abstract

Experimental data on the effects of cleavers (Galium aparine) and yarrow (Achillea millefolium) extracts on rumen microbial fermentation are scarce. The objective of this study was to determine the effects of cleavers and yarrow extracts on in vitro ruminal fermentation. Incubation trial was carried out using the long-term rumen simulation technique (RUSITEC). The experiment lasted 10 days. After an adaptation period of 5 days, the fermentation vessels divided into 3 groups; first three vessels received no additives (control), second three vessels received 500 mg/L cleavers extract daily, and third three vessels received 500 mg/L yarrow extract daily. Supplementations of cleavers and yarrow extracts had no significant effect on ruminal pH, total volatile fatty acids (VFA), acetate, propionate and methane production, NH3-N concentration and, total protozoa. However, both extracts decreased dry matter digestibility (DMD) (P<0.05). Butyrate production, on the other hand, increased with cleavers extract (P<0.05). In conclusion, there were only small effects of cleavers and yarrow extracts on the investigated microbial fermentation characteristics. Nevertheless, it may be considered advantageous for feed conversion that plant extracts did not suppress ruminal fermentation in spite of decreasing DMD.

Keywords

• achillea millefolium
• cleavers
• galium aparine
• plant extracts
• rumen
• rusitec
• yarrow