Tear production in normal juvenile dogs.

OBJECTIVE: To establish a baseline range or average for tear production in normal juvenile dogs and evaluate the effects of age, weight, and gender on Schirmer tear test (STT) in juvenile dogs. MATERIALS AND METHODS: Healthy puppies of various breeds <6 months of age. STT1 and STT2 were performed in both eyes of each subject. Statistical analysis was performed using a backwards stepwise regression model with repeated measures. Using continuous variables of STT1 and STT2 as the dependent variables separately, the independent variables were age (days), eye (left or right), gender (male or female), ocular disease processes in eyes or not, and weight (kg). RESULTS: Eighty-six eyes from 27 males and 16 females were included in this study. Ages ranged from 25 to 133 (mean ± SEM: 61.74 ± 24.15) days and weights ranged from 0.88 to 8.86 (3.27 ± 2.22) kg. STT1 results ranged from 0 to 26 (15.76 ± 5.79) mm/min. STT2 results ranged from 0 to 24 (8.79 ± 5.01) mm/min. Age, weight, and gender significantly affected STT1 results. Weight and gender significantly affected STT2 results. STT1 values increased by 0.15 mm/min for each 1 day increase in age and by 0.84 mm/min for each 1 kg increase in body weight. STT2 values increased by 0.57 mm/min for each 1 kg increase in body weight. CONCLUSIONS: Age, weight, and gender significantly affect tear production in normal juvenile dogs. STT1 increases to adult values at approximately 9-10 weeks of age.

Effect of body position on intraocular pressure in dogs without glaucoma.

OBJECTIVE: To determine the effects of body position on intraocular pressure (IOP) in dogs without glaucoma. ANIMALS: 24 healthy dogs with no evidence of glaucoma. PROCEDURES: Dogs underwent ophthalmic examinations to ensure that no IOP-affecting ocular diseases were present. Each dog was sequentially placed in dorsal recumbency, sternal recumbency, and sitting position. For each of the 3 positions, IOP in the right eye was measured by use of an applanation tonometer immediately after positioning (0 minutes) and after 3 and 5 minutes had elapsed. The initial body position was randomly assigned; each position followed the other positions an equal number of times, and IOP measurements were initiated immediately after moving from one body position to the next. Proparacaine hydrochloride (0.5%) was applied to the right eye immediately prior to IOP measurements. RESULTS: Intraocular pressure was affected by body position. During the 5-minute examination, IOP decreased significantly in dogs that were dorsally recumbent or sitting but did not change significantly in dogs that were sternally recumbent. For the 3 positions, overall mean IOP differed significantly at each time point (0, 3, and 5 minutes). Mean IOP in dorsal recumbency was significantly higher than that in sternal recumbency at 0 and at 3 minutes; although the former was also higher than that in sitting position at 3 minutes, that difference was not significant. CONCLUSIONS AND CLINICAL RELEVANCE: Body position affects IOP in dogs. When IOP is measured in dogs, body position should be recorded and consistent among repeat evaluations.

Ophthalmic examination findings in adult pygmy goats (Capra hicus).

OBJECTIVE: To document normal ophthalmic findings and ocular abnormalities in captive adult pygmy goats. ANIMALS STUDIED: Ten healthy adult pygmy goats (five male, five female; 5-11 years of age; 26-45 kg body mass) underwent complete ophthalmic examinations. PROCEDURE: Direct illumination, diffuse and slit-beam biomicroscopy, indirect ophthalmoscopy, IOP measurements and Schirmer tear tests were performed. TonoVet rebound tonometry, followed by topical application of 0.5% ophthalmic proparacaine, and Tono-Pen XL applanation tonometry were performed in each eye to obtain estimates of IOP. RESULTS: Ophthalmic abnormalities included corneal scars and pigmentation, incipient cataracts, lenticular sclerosis, and vitreal veiling. Mean STT values were 15.8 mm/min, with a range of 10-30 mm/min. Mean IOP values were 11.8 mmHg for TonoVet-D, with a range of 9-14 mmHg; 7.9 mmHg for TonoVet-P, with a range of 6-12 mmHg; and 10.8 mmHg for Tono-Pen XL, with a range of 8-14 mmHg. CONCLUSIONS: Ophthalmic examination findings in adult pygmy goats, including normal means and ranges for STT and IOP measurements, using applanation and rebound tonometry, are provided.