Prevalence of Pentatrichomonas hominis in foxes and raccoon dogs and changes in the gut microbiota of infected female foxes in the Hebei and Henan Provinces in China

Pentatrichomonas hominis (P. hominis) is a zoonotic parasite that affects a wide range of hosts, causing gastrointestinal diseases. The present study aimed to evaluate the prevalence of P. hominis among caged foxes and raccoon dogs and the effect of P. hominis on the gut microbiota in female foxes. A total of 893 fresh fecal samples were collected from the Hebei and Henan Provinces in China. P. hominis was screened based on 18S rRNA gene expression via nested PCR. The difference in the gut microbiota between nine P. hominis-positive and nine P. hominis-negative samples was investigated by 16S rRNA gene sequencing. The total prevalence of P. hominis infection in foxes and raccoon dogs was 31.7% (283/893). The prevalence rates of P. hominis infection were 28.2% (88/312) and 33.6% (195/581) in foxes and raccoon dogs, respectively. Phylogenetic analysis revealed that all P. hominis strains detected in foxes and raccoon dogs in the present study were the zoonotic genotype CC1. Moreover, compared with those in the P. hominis-negative group, the diversity of the gut microbiota in the P. hominis-positive group was lower, and the abundance of Firmicutes and the ratio of Firmicutes/Bacteroidetes (F/B) in the P. hominis-positive group were lower than those in the P. hominis-negative group. We speculate that these differences may be due to indigestion and diarrhea in infected female foxes. Overall, the present study evaluated the prevalence of P. hominis in foxes and raccoon dogs in the Henan and Hebei Provinces and revealed that P. hominis infection interrupted the diversity of the gut microbiota in female foxes.

Evaluation of gut microbiota composition to screening for potential biomarker in AFB1-exposed sheep

Aflatoxin B1 (AFB1) is an inevitable contaminant in animal feed and agricultural products, which seriously threatens the health of animals. However, there is currently no better diagnostic tool available than depending on clinical symptoms, pathophysiology, biochemical indicators, etc. Here, we profiled the fecal microbiomes of sheep exposed to and not exposed to AFB1 to identify potential non-invasive biomarkers of AFB1 intoxication by 16S rRNA gene sequencing technology, while measuring serum biochemical indexes. The results showed that the sheep exposed to AFB1 had significantly higher levels of the liver function indicators ALT (alanine transaminase) and AST (aspartate aminotransferase), and their microbial profiles were different from those of the CON (Control) group. In detail, the relative abundance of seven phyla and three genera were overrepresented in the AFB1 group from top 10 relative abundance. Importantly, we found that Prevotella and Bifidobacterium were significantly different in the CON and AFB1 groups (p = 0.032 and p = 0.021, respectively) based on linear discriminant analysis effect size (LEfSe) and random forest analysis. Additionally, the area under curve (AUC) of ALT was 1 (95% CI 1.00-1.00; p < 0.001) and that of Bifidobacterium was 0.95 (95% CI 0.81-1.00; p = 0.0275), suggesting that Bifidobacterium correlated with ALT (r = 0.783, p < 0.01) may be a potential biomarker for AFB1 exposure in sheep.