Ocular findings and selected ophthalmic diagnostic tests in a group of young commercially available Guinea and Skinny pigs (Cavia porcellus)

Abstract

Objective The purpose of this study is to evaluate a group of young commercially available Skinny pigs, to gain information regarding ocular findings in this breed of guinea pig. Comparisons of ocular findings are to be made between Skinny pigs and haired guinea pigs. Animal studied Ten haired guinea pigs and ten Skinny pigs were examined. Procedure A complete ophthalmic examination including Schirmer tear test‐II (STT‐II), phenol red thread test (PRTT), rebound tonometry with TonoVet PLUS, Fluorescein and Rose Bengal stain was performed. Microbiology swabs for aerobic bacterial growth were collected from conjunctiva of both eyes prior to the ophthalmic examination. Results The ophthalmic examination revealed seven abnormal ocular findings: trichiasis, mucopurulent discharge, hyperemia/chemosis of the conjunctiva, corneal fibrosis, corneal vascularization, and foreign body on the cornea or conjunctiva. Skinny pigs had a significantly higher amount of mucopurulent discharge (P = .0133) and a significantly higher STT‐II (P < .001) than haired guinea pigs. Although not significant, trichiasis, keratitis with corneal vascularization, and foreign body presence were more common in Skinny pigs. Significantly more Skinny pigs had Pasteurellaceae isolated from their conjunctiva than haired guinea pigs (P = .0112). Antimicrobial susceptibility for the five Pasteurellaceae organisms isolated revealed susceptibility toward oxytetracycline, tobramycin, ciprofloxacin, and ofloxacin, whereas resistance was found toward erythromycin, trimethoprim‐sulfamethoxazole, and moxifloxacin. Conclusion Young Skinny pigs have a higher risk of Pasteurellaceae‐associated conjunctivitis. Oxytetracycline, tobramycin, ciprofloxacin, and ofloxacin were identified as topical antibiotics that may be useful for Pasteurellaceae‐associated conjunctivitis in Skinny pigs.

Clinical ophthalmological diagnostic description of 10 healthy sugar gliders (Petaurus breviceps) and prevalence of ocular‐related presentations in a larger hospital population

“…Gram‐positive bacteria, in particular Staphylococcus spp. and Corynebacterium spp., have been reported as commensal conjunctival organisms in dogs, 30,31 cats, 32,33 rabbits, 34 guinea pigs, 11,19 chinchillas, 35 and Syrian hamsters 36 . Micrococcus spp.…”

“…STT has been successfully performed in other marsupial species, 13,16 indicating phylogeny may not be affecting the results of these diagnostics. PRTT has been successfully used in other ZCA mammals to measure tear film 11,15,17‐19 …”

“…One drop (0.05 ml) of proparacaine 0.5% ophthalmic solution (Bausch + Lomb Inc) was applied OU for topical analgesia. Excessive proparacaine ophthalmic solution was removed prior to tear testing using a cotton‐tipped applicator at the medical canthus as described in guinea pigs 11 . Tear production was quantified with Schirmer Tear Test II (STT) (OptiTech® Eye Care, Tarun Enterprises) and phenol red thread tests (PRTT) (Zone‐Quick, AYUMI Pharmaceutical Corporation) OU in every eye.…”

“…Rebound tonometry (TonoVet PLUS tonometer, iCare®, Helsinki, Finland) in the ‘rabbit’ calibration setting was used to measure IOPs prior to pupil dilation. The rabbit setting was selected due to a study in guinea pigs by Wu et al 11 As is standard practice, six pressure measurements were taken and averaged to produce a final value of pressure in mmHg. Only readings with low or no error were accepted, indicated by a green ring around the measured IOP number.…”

“…Prior to the ophthalmic examination, described above, bacterial culture was obtained by placing a sterile cotton‐tipped swab (BD BBL TM CultureSwab TM Plus, Fisher Scientific) into the medial canthus of each eye with the third eyelid elevated, avoiding contact with periocular skin or hair (Figure 5A). Two variations of the swab collection procedure were used: pre‐moistening the sterile swab with one drop (0.05 ml) of sterile saline (Sterile Water, Hospira Inc) prior to sample collection as described in guinea pigs, 11 and using an un‐moistened swab. The procedure used was alternated between sugar gliders to determine which would be more effective in yielding bacterial growth.…”