Industrial hemp could potentially contribute to livestock nutrition including in the sheep industry; however, the impact of feeding industrial hemp on the gastrointestinal microbiome of sheep remains poorly characterised. Previous investigations indicated that rumen parameters, including volatile fatty acid molar proportions, and fibre digestibility of a pelleted diet were altered following inclusion of industrial hemp stubble or hay in sheep diets, suggesting modulation of the gastrointestinal microbiome by industrial hemp. Therefore, to characterise this relationship, a preliminary experiment was conducted by profiling the ruminal fluid and faecal microbiome of sheep fed a pelleted diet containing 42% industrial hemp hay. Twelve Merino ewes were allocated to either a Control or industrial hemp diet (n = 6 per treatment) for 21 d following a 6 d transitional period. A ruminal fluid and faecal sample were collected from each sheep 3 h post-feeding at the end of the feeding trial and subjected to 16S rRNA gene sequencing. While no differences (p > 0.05) in alpha diversity were observed, analyses revealed differences (p < 0.05) in the relative abundance of microbial taxa at both the phylum and genus levels. In the faeces, there was an increase in Firmicutes and subsequent decrease in both Bacteroidota and Spirochaetota at the phylum level and an increase in both Acetitomaculum and Blautia and subsequent decrease in both Treponema and Rikenellaceae_RC9_gut_group at the genus level. In the rumen, there were no differences at the phylum level but at the genus level there was an increase in both Olsenella and Eubacterium_hallii_group. Beta diversity analysis demonstrated a decrease in between-sample phylogenetic similarity in both the faeces and rumen (p = 0.006 and p = 0.002, respectively for ANOSIM analysis) following industrial hemp consumption, indicating a discernible influence on the ovine gastrointestinal microbiome. Variations in the overall microbial community structure following industrial hemp ingestion may have influenced digestion and nutrient utilisation, contributing to the changes in fibre digestibility and ruminal parameters identified following feeding of industrial hemp to sheep. Further research is required to ensure there are no adverse animal health or production effects post feeding.
Pasteurella multocida is a major causative agent of respiratory disease in goats; however, genomic data on strains in Hubei Province remain scarce. In this study, two P. multocida strains of serotypes A and D were isolated from goats with respiratory disease on intensive farms in Jingmen City and Shiyan City, Hubei Province. Phenotypic antimicrobial susceptibility testing revealed that both strains were resistant to streptomycin, sulfisoxazole, co-trimoxazole, and lincomycin, while remaining susceptible to most other antibiotics tested. A murine infection model demonstrated that the serotype D strain exhibited significantly higher virulence than the serotype A strain. Based on its elevated pathogenicity, the serotype D strain was selected for whole-genome sequencing. Genomic analysis identified a circular chromosome of 2353,913 bp carrying 101 antimicrobial resistance genes and 56 virulence-associated genes, including the toxA gene. Notably, considerable discrepancies were observed between the genotypic resistance predictions derived from whole-genome sequencing and the phenotypic susceptibility profiles obtained by disk diffusion testing. This finding demonstrates that genome-based resistance prediction alone is insufficient and potentially misleading for guiding antimicrobial therapy, as in silico predictions may overestimate resistance (e.g., due to unexpressed or dysfunctional resistance genes) and fail to capture phenotypically expressed resistance. These results underscore that antimicrobial resistance surveillance and clinical treatment decisions must integrate both genomic and phenotypic approaches, and that phenotype-based confirmation remains indispensable for accurate and reliable therapeutic guidance in veterinary practice.
