Exploring the anticoccidial efficacy of Houttuynia cordata: Insights into gut microbiota modulation and metabolic enhancement in lambs.

Eimeria primarily infects the intestinal epithelial cells of livestock and poultry, disrupting gut microbiota and metabolism, which can result in diarrhea and weight loss. In severe cases, it can lead to hematochezia and even mortality. Modern intensive and large-scale farming practices, combined with the fecal-oral transmission of coccidia, create environments conducive to coccidial infections. Chemical control methods may lead to drug residues, drug resistance, toxic side effects, and other related issues. In contrast, Chinese herbal medicines typically exhibit multi-target, multi-pathway, and synergistic properties in disease resistance. In this study, the McMaster counting method was employed to assess the anti-coccidial effects of Houttuynia cordata (H. cordata) in its untreated forms (raw, water extract, and alcohol extract). The impact of these treatments on the intestinal microbiota and metabolites of lambs was examined using 16S rRNA gene sequencing technology and non-targeted metabolomics. The findings indicated that H. cordata reduced the excretion of intestinal coccidian oocysts in lambs. Notably, the alcohol extract of H. cordata (HA) significantly enhanced the average daily weight gain (ADG) and increased the abundance of unclassified Lachnospiraceae, Christensenellaceae R_7 group, and UCG_005. Additionally, metabolites such as 6-Deoxyerythronolide B, Parthenolide, and Bacilysin were highlighted for their potential significance. Overall, HA demonstrated superior anticoccidial effects and improved weight gain, likely due to the enhancement of beneficial microbiota and metabolites. This study provides a theoretical foundation for understanding the mechanisms by which Chinese herbal medicine combats coccidiosis through the modulation of intestinal microbiota and metabolism.