Measurement of tear production and intraocular pressure in ducks and geese

Objectives The purpose of this study was to establish a reference value of tear production and intraocular pressure in clinically normal ducks and geese. Animal Studied The study population consisted of forty-eight ducks (24 males and 24 females) and fifty-two geese (26 males and 26 females). Procedures Birds were gently physically restrained in dorsoventral position without any pressure to the head and neck. Tear secretion and intraocular pressure were measured using 5-mm-wide Schirmer tear test strips and TonoVet® rebound tonometer, respectively. Results Overall mean ± 2SD STT and IOP values of all eyes were 6.2 ± 2.2 mm/min and 10.2 ± 2.2 mmHg, respectively, for the ducks; 5.5 ± 2.6 mm/min and 9.1 ± 2.0 mmHg, respectively, for the geese. There was no statistically significant difference in IOP between left eye and right eye or between males and females in ducks (P = 0.56, P = 0.63) and geese (P = 0.23, P = 0.22). Analysis of variance revealed that there were no significant differences in the STT and IOP between the breeds in ducks (P = 0.49, P = 0.68) and geese (P = 0.14, P = 0.26). Conclusions Results of this study may be beneficial for the diagnosis and therapeutic monitoring of ducks and geese affected with Keratoconjunctivitis sicca, glaucoma, and uveitis.