The ruminant is less efficient than other species in the utilization of dietary protein. Nitrogen losses from ruminants are exceptionally high, particularly in grazing animals. This is an environmental problem as well as an economic one, because of the impact of nitrogen-rich excreta on the environment. Improving the protein retention in the rumen could be done by the suppression of the population of rumen ciliate protozoa. Protozoa consume large quantities of bacteria in the rumen, their breakdown can result in a decrease of the net yield of microbial protein from rumen fermentation of up to 50%. If the protozoa could be suppressed, there would be less ammonia formation and less need for dietary protein supplementation.
The project results showed that this can be achieved by orally administering, suitably via the animal feed or the drinking water, an additive containing one or more components of plant materials selected from the group consisting of Lonicera japonica, Gentiana asclepidea, Gentiana lutea, Eugenia caryophyllata, Bellis perennis, Olea europaea, Symphytum officinale, Carduus pycnocephalus, Paeoniae alba radix, Populus tremula, Prunus avium, Salix caprea, Rheum nobile, Helianthemum canum, Arctostaphylos uva-ursi, Peltiphyllum peltatum, Epilobium montanum, Knautia arvensis, Latuca sativa and Urtica dioica and extracts thereof, and â-myrcene. The total amount of the components administered to an animal is suitably from 0.02mg to 20g per day and kg bodyweight.