A red clover-based dietary intervention limits nematode egg excretion and reshapes parasite-host-microbiome interplay within the sheep abomasum

Although anthelmintics remain the primary control strategy, resistance is becoming increasingly widespread. Thus, sustainable alternatives are urgently needed to improve parasite control and support animal health.

We formulated a red clover–based forage diet using the biorefinery by-product red clover pulp. In sheep infected with three common GIN species, this diet reduced fecal egg counts by ~40% (P = 0.0006) without negatively affecting feed intake or weight gain. The diet also significantly increased the abundance of Bacteroidales RF16 and Bacteroidales p-251-o5, taxa associated with short-chain fatty acid production, while reducing Methanomethylophilaceae, a family linked to methane production.