Effects of different climatic conditions on intraocular pressure in Arabian horses
Abstract
This study aimed to investigate the effects of different climatic conditions on intraocular pressure in Arabian horses. intraocular pressure is a critical parameter for the diagnosis and management of ocular diseases such as glaucoma and anterior uveitis, and accurate measurement is essential for equine eye health. The present study was conducted on 15 clinically healthy Arabian horses aged between 6 and 10 years and kept under the climatic conditions of Eastern Anatolia, Türkiye. Intraocular pressure measurements were performed at two different environmental temperatures, 5 °C and −20 °C, to evaluate the effect of ambient temperature on ocular physiology. During the measurements, the head position of the horses was kept at shoulder level, and no sedatives or topical anesthetics were administered to avoid possible interference with intraocular pressure values. Measurements were obtained using an Icare® rebound tonometer, and for each eye, six consecutive readings were recorded, with the mean value used for statistical evaluation. The analysis showed no statistically significant difference between the right and left eyes at either temperature level, indicating that intraocular pressure measurements obtained from both eyes can be used interchangeably without introducing systematic bias. At 5 °C, mean intraocular pressure values were 28.53 ± 4.88 mmHg in the right eye and 28.07 ± 4.30 mmHg in the left eye. When the ambient temperature decreased to −20 °C, mean intraocular pressure values increased to 32.33 ± 3.05 mmHg and 32.00 ± 2.09 mmHg for the right and left eyes, respectively. Statistical analyses, including paired t-tests and Bland– Altman evaluation, demonstrated that this increase was significant and consistent, and that it was not dependent on the magnitude of the measurements. These findings indicate that low environmental temperature has a clear physiological effect on intraocular pressure in Arabian horses. The absence of interocular differences further supports the reliability of the measurements and the suitability of using either eye for clinical assessment. Taken together, the results emphasize the importance of considering environmental temperature when interpreting intraocular pressure values, particularly in regions with extreme climatic conditions. Future studies involving different climatic zones, breeds, and age groups would be valuable to confirm and expand upon these findings.
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