Characterization of Conjunctival Bacterial Flora of Healthy Laboratory‐Housed New Zealand White Rabbits

Objective To characterize the conjunctival bacterial flora of laboratory‐housed New Zealand White (NZW) rabbits using conventional culture techniques and quantitative bacterial analysis. Animals Studied This experimental study involved the collection of conjunctival fornix samples from 24 eyes of 12 healthy laboratory‐housed NZW rabbits. Procedures Conjunctival samples were obtained using sterile dry swabs and processed using standard microbiological techniques. Bacterial identification was performed via mass spectrometry (MALDI‐TOF), and quantification was expressed in colony‐forming units per milliliter (CFU/mL). Results Bacterial growth was observed in 74% of the samples (17/24 eyes), with seven species identified: Moraxella cuniculi , Corynebacterium spp., coagulase‐negative Staphylococcus , Bacillus spp., Staphylococcus aureus , Streptococcus viridans group, and Tsukamurella spp. Although most isolates were Gram‐positive, M. cuniculi —a Gram‐negative bacterium—was the predominant species. It exhibited the highest bacterial load (CFU/mL) and demonstrated a statistically significant difference compared to the other species (Kruskal–Wallis, p = 0.01). M. cuniculi also exhibited the highest variability in CFU/mL values among all isolates. Conclusions Despite the predominance of Gram‐positive isolates, M. cuniculi was identified as the predominant species in the conjunctival flora of healthy NZW rabbits, both in frequency and bacterial load. These findings contribute to a more detailed characterization of the ocular microbiota in this commonly used laboratory model.