Determination of Tear Volume and Intraocular Pressure in Saanen Goat and Sakiz Sheep in Similar Environmental Conditions

Abstract views: 356 / PDF downloads: 210



Goat, intraocular pressure, Saanen, Sakiz sheep, Schirmer tear test


The aim of this study is to identify physiological reference values for Schirmer tear test (STT) and intraocular pressure (IOP) results, in healthy sheep and goats. The study included 56 adult Sakiz sheep and 38 Saanen goats with no ocular disease. Tear volume was measured by a sterile STT strip. IOP was measured with Tono-Vet. IOP and STT readings were carried out in July, at 12.30-14.30 hrs. Measurements were write down in similar conditions in sheep and goats (at 41.8°C-30% humidity and 40.5°C and 32% humidity, respectively). No statistically significant difference was determined between the mean IOP and STT values of the left eye and the right eye in the statistical analysis of goats and sheep (P>0.05). The mean STT values were 10.6±3.03 mm/min in Saanen goats and 11.8±3.35 mm/min in Sakiz sheep. The mean IOP values were 16.5±5.46 mmHg and 17.7±4.57 mmHg for Saanen goats and Sakiz sheep, respectively. A statistically significant difference was determined in the STT (P<0.05) and IOP (P<0.01) values between goats and sheep. In the literature review for reference IOP and STT levels, there is no report for Sakız sheep. Reference values of STT and IOP in summer conditions in Saanen goats and Sakiz sheep were revealed and provide more information for experimental and clinical studies.


Ali KM, Abdelgalil AI, Hassan EA, Torad FA. 2020. Circadian Rhythm of Intraocular Pressure in Clinically Normal Donkeys ( Equus Asinus ). Biological Rhythm Research, May, 1–10.

Broadwater JJ, Schorling JJ, Herring IP, Pickett JP. 2007. Ophthalmic Examination Findings in Adult Pygmy Goats (Capra Hicus). Veterinary Ophthalmology, 10 (5): 269–73.

Faulkner J, Williams DL, Mueller K. 2020. Ophthalmology of Clinically Normal Alpacas ( Vicugna Pacos ) in the United Kingdom: A Cross-Sectional Study. Veterinary Record, 186 (16): e7–e7.

Garzón-Ariza A, Guisado A, Galán A, Martín-Suárez E. 2018. Diurnal Variations in Intraocular Pressure and Central Corneal Thickness and the Correlation between These Factors in Dogs. Veterinary Ophthalmology, 21 (5): 464–70.

Gelatt KN, Gilger BC, Kern TJ. 2013. Veterinary Ophthalmology 5th Edn: Two Volume Set. Edited by Thomas J. Kern Kirk N. Gelatt, Brian C. Gilger. 5th ed. Oxford: Wiley-Blackwell.

Gerometta R, Podos SM, Danias J, Candia OA. 2009. Steroid-Induced Ocular Hypertension in Normal Sheep. Investigative Opthalmology & Visual Science, 50 (2): 669.

Ghaffari MS, Shojaei M, Sabzevari A, Khorami N. 2011. Reference Values for Intraocular Pressure and Schirmer Tear Test in Clinically Normal Sanjabi Sheep. Small Ruminant Research, 97 (1–3): 101–3.

Görig C, Coenen RTI, Stades FC, Djajadiningrat-Laanen SC, Boevé MH. 2006. Comparison of the Use of New Handheld Tonometers and Established Applanation Tonometers in Dogs. American Journal of Veterinary Research, 67 (1): 134–44.

Hartley C, Williams DL, Adams VJ. 2006. Effect of Age, Gender, Weight, and Time of Day on Tear Production in Normal Dogs. Veterinary Ophthalmology, 9 (1): 53–57.

Irby NL. 2004. Surgical Diseases of the Eye in Farm Animals. Farm Animal Surgery, 429–59.

Van Kampen KR, James LF. 1971. Ophthalmic Lesions in Locoweed Poisoning of Cattle, Sheep, and Horses. American Journal of Veterinary Research, 38: 1293–95.

Kovalcuka L, Boiko D, Williams DL. 2018. Tear Production and Intraocular Pressure Values in Clinically Normal Eyes of Whooper Swans (Cygnus Cygnus). Open Veterinary Journal, 8 (3): 335.

Moore CP, Whitley RD. 1984. Ophthalmic Diseases of Small Domestic Ruminants. Veterinary Clinics of North America: Large Animal Practice, 6 (3): 641–66.

Mustikka MP, Pietilä EM, Mykkänen AK, Grönthal TSC. 2020. Comparison of Two Rebound Tonometers in Healthy Horses. Veterinary Ophthalmology, 23 (5): 892–98.

Ofri R, Steinmetz A, Thielebein J, Horowitz IH, Oechtering G, Kass PH. 2008. Factors Affecting Intraocular Pressure in Lions. The Veterinary Journal, 177 (1): 124–29.

Oriá AP, Oliveira AVD, Pinna MH, Martins Filho EF, Estrela-Lima A, Peixoto TC, da Silva RMM, Santana FO, Meneses IDS, Requiao KG, Ofri R. 2015. Ophthalmic Diagnostic Tests, Orbital Anatomy, and Adnexal Histology of the Broad-Snouted Caiman (Caiman Latirostris). Veterinary Ophthalmology, 18 (January): 30–39.

Pigatto JAT, Pereira FQ, Albuquerque L, Corrêa LFD, Bercht BS, Hünning PS, Silva AAR, de Freitas LVRP. 2011. Intraocular Pressure Measurement in Sheep Using an Applanation Tonometer. Revista Ceres, 58 (6): 685–89.

Ribeiro AP, Piso DYT, Padua IRM, Silva ML, Laus JL. 2010. Intraocular Pressure and Tear Secretion in Saanen Goats with Different Ages. Pesquisa Veterinária Brasileira, 30 (9): 798–802.

Smith MC. 2017. Small Ruminant Ophthalmology. Omaha: In: American Association of Bovine Practitioners Proceedings of the Annual Conference.

Snyder KC, Lewin AC, Mans C, McLellan GJ. 2018. Tonometer Validation and Intraocular Pressure Reference Values in the Normal Chinchilla (Chinchilla Lanigera). Veterinary Ophthalmology, 21 (1): 4–9.

Sole MJ Del, Sande PH, Bernades JM, Aba MA, Rosenstein RE. 2007. Circadian Rhythm of Intraocular Pressure in Cats. Veterinary Ophthalmology, 10 (3): 155–61.

Williams DL, Tighe A. 2018. Immunohistochemical Evaluation of Lymphocyte Populations in the Nictitans Glands of Normal Dogs and Dogs with Keratoconjunctivitis Sicca. Open Veterinary Journal 8 (1): 47–52.




How to Cite

Kibar Kurt, B., Bulut, O., Bozkan, Z., Bilgen Şen, Z., & Belge, A. (2021). Determination of Tear Volume and Intraocular Pressure in Saanen Goat and Sakiz Sheep in Similar Environmental Conditions. International Journal of Veterinary and Animal Research (IJVAR), 4(3), 78–82. Retrieved from



Research Articles