Minimal disruption of equine gut microbiota by intravenous cephalothin treatment.

The research study assesses the impact of a particular antibiotic, cephalothin, when administered intravenously on a horse’s gut microbiota. They found that it has minimal effects, providing evidence of a lower risk of disruption to the equine microbiota compared to other antimicrobials.

Study Design

• The research study was set up to sample the fecal microbiota of horses undergoing different antibiotic treatments, as well as those suffering from colitis, versus clinically normal horses.
• 39 clinically normal horses served as controls while another 16 were treated with various antibiotics (cepahlothin, minocycline, and metronidazole, all dosage administered for 5 days) and 7 were affected with colitis.
• The researchers used microbial amplicon sequencing targeting the 16S-ITS-23S rRNA operon to study how the gut microbiota was impacted by these different conditions.

Findings

• The researchers found that cephalothin appeared to have minimal effect on the gut microbiota. There were no significant differences in α-diversity and β-diversity (measures of microbial diversity in the gut) between horses treated with cephalothin and those that were clinically normal.
• In contrast, the antibiotics minocycline and metronidazole significantly disrupted microbial composition of the gut. Colitis-afflicted horses likewise displayed markedly different microbiota profiles with reduced species richness, indicating a noteworthy impact of disease on these flora.

Interpretation

• The fact that none of the microbial families significantly altered in the colitis-affected horses changed in response to cephalothin suggests this antibiotic has a minimal effect on the gut microbiota of the subjects.
• In particular, the consistent abundance of Verrucomicrobia subdivision 3 – which is associated with supporting mucosal integrity – suggests that cephalothin might be a safer option compared to other antimicrobials which tend to significantly reduce the relative abundance of this important microbe group.
• The researchers conclude that the use of cephalothin in veterinary practices could potentially ensure effective infection control while reducing the risk of gastrointestinal complications by maintaining gut microbial balance.
• This study, thus, provides valuable evidence for the selection of antimicrobials, contributing to the optimization of veterinary therapeutic approaches and supporting equine gut microbiota health.