The role of the rumen microbiome in detoxifying forage mycotoxins and improving dairy cow health and welfare

Grass silage is the main forage fed to ruminants in the UK, and under adverse forage growing conditions or aerobic contamination of clamps or bales at feed-out, fungal spoilage can be widespread. Under these conditions fungi can produce secondary compounds such as mycotoxins, which has been reported to occur in up to 90% of forage fed to cattle in temperate regions such as UK, Ireland and Northern Europe. When present in the diet of cattle, mycotoxins and biologically active breakdown products can negatively affect health, fertility and production, and in extreme cases lead to death. Moreover, there is a risk that mycotoxins can be passed into the human food chain via the milk or meat. The ability of the rumen microbiome to efficiently ferment forages is also dependent on a delicate balance of microbial species that can break down fibre and protein in the diet. An imbalance or shift in microbial population as a result of mycotoxin ingestion may reduce digestive efficiency and subsequently reduce health, milk performance and fertility.
There is, however, a lack of knowledge on the conditions that lead to mycotoxin production in grass silage, and their subsequent effect on the rumen microbiome, dairy cow metabolism and health. Additionally, the negative effects of mycotoxins may be mitigated by the addition of binders to the diet, although there is a lack of research on their effectiveness in grass silage based diets
This project will investigate the effect of mycotoxins in grass silage on the rumen microbiome, rumen metabolism and performance in dairy cows, and assess the efficacy of feed binders on mitigating their effects.