In vitro effects of phenolic acids and IgY immunoglobulins on aspects of rumen fermentation

The current study was carried out in order to determine the effects of simple phenols and of specific anti-methanogen IgY antibodies on ruminal gas production, methane emissions, volatile fatty acids (VFA) profile and pH in in vitro ruminal cultures. Caffeic and p-Coumaric acids and IgY antibodies were added anaerobically to ruminal batch cultures. Ruminal parameters were measured after 24, 48 and 72 hours of incubation. The results showed that addition of both phenolic acids and IgY antibodies significantly (P <0.05) decreased methane production at 24 and 48 hours of incubation. At 24 and 48 hours of incubation some significant differences were observed in volatile fatty acids profile, while the pH was not affected by simple phenols and IgY antibodies addition. Simple phenols and IgY avian antibodies can be further tested in order to achieve the purpose of methane mitigation strategies, but the ideal way to inhibit the methanogenesis process in rumen would reduce methane production without altering the other ruminal parameters, such as VFAs, total gas production or pH.