A study was designed to learn more about the effect of nature based solutions to improve nitrogen utilization in dairy cows. In current practice, soybeans are processed and/or treated with chemicals such as formaldehyde to reduce rumen degradability and increase the content of intestinal digestible protein. It can be debated if the use of formaldehyde is the most sustainable and favorable solution. IDENA developed a feed additive Vertan, a blend of Eugenol, Thymol and essentials oils, as an alternative for chemical feed processing of protein-rich feed ingredients such as soybean meal.
To evaluate the effect of Vertan on performance and nitrogen use efficiency, a feeding trial was conducted with three groups of 15 dairy cows. After a pre-period cows were grouped and allotted to one of the following treatments. A negative control diet with untreated soybean meal (SBM) in the diet, a positive control diet with formaldehyde treated soybean meal (SBM-bp; bp stands for by-pass) and a treatment diet with soybean meal supplemented with Vertan (SBM-V; V stands for Vertan). Parallel to the performance study, three cows fitted with a rumen cannula were used in a Latin square design to measure rumen characteristics, the in situ rumen degradation of the soybean meals and total diets, and fecal digestion. To back up the findings on the mode of action of the feed additive, a simulation with a rumen fermentation model was included in the study to mimic the effect of soybean meal characteristics on fermentation, digestibility and emissions.
Figure 1: Schematic design: feeding trial (B), fermentation trial (A) and model predictions (C)
From this study it is concluded that the use of Vertan, as a nature based solution for improved feed protein utilisation, has an effect on rumen fermentation and milk protein. Supplementing Vertan has an effect on rumen protein fermentation and VFA concentrations, resulting in lower in vivo rumen ammonia, iso-valeric and valeric acid concentrations and a lower blood urea concentration.These results are indicators for a better protein utilisation. However, not all results could be fully explained by the outcome of in situ measurements on nitrogen degradation or by model predictions.