Investigation of Tear Measurement Methods (STT, PRT) in Immature Persian cat

Subject Areas : Smal Animal Medicine

seyed morteza Razaghi Manesh ¹ , Seyedeh Omolbanin Ghasemian ² , Maryam Kamipour ³ , Saba Bonyadi Dehkordi ⁴ , Ava Abrisham Kar ⁵

1 - Department of Veterinary Medicine, Faculty of Agriculture and Veterinary Medicine, Shushtar Branch, Islamic Azad University, Shushtar, Iran
2 - Department of Veterinary Medicine, Faculty of Veterinary Medicine, Islamic Azad University, Behbahan Branch, Behbahan, Iran
3 - Doctor of Veterinary Medicine graduate, Shushtar Branch, Islamic Azad University, Shushtar, Iran
4 - Doctor of Veterinary Medicine student, Shushtar Branch, Islamic Azad University, Shushtar, Iran
5 - Animal Biology student at the University of Guelph, Ontario, Canada

Received: 2025-04-22 Accepted : 2025-07-25 Published : 2025-07-26

Keywords: STT, PRT, Tear film, Immature Persian Cat,

Abstract :

This study investigated the effectiveness of the phenol red thread test (PRT) and the Schermer tear test (STT) in assessing tear production in immature Persian cats. The tear film is essential for protecting the ocular surface, and accurate assessment of tear production is crucial in veterinary ophthalmology, especially for breeds such as the Persian cat that are prone to ocular disorders. Twenty Persian kittens aged 6 to 12 weeks were randomly assigned to two groups of 10 for the Schermer test and the phenol red thread test. The results show that both tests are effective in measuring tear production. However, the PRT showed a higher degree of ease of administration and lower levels of irritation to the cats. A significant correlation was found between tear production levels and the age of the kittens, while the PRT showed comparable sensitivity and specificity to the STT. These findings provide valuable information for veterinarians regarding the selection of appropriate methods for assessing tear production in Persian cats. This research emphasizes the importance of early detection and management of ocular surface disorders, which ultimately helps improve clinical outcomes for this breed. This study enriches the existing knowledge in the study of ocular diseases by highlighting the practical applications of appropriate diagnostic tests for Persian cats.

References:


1. Sağlam, K., & Düz, E. (2023). Measurement of Tear Production in Van Cats with the Phenol Red Thread Test. Van Veterinary Journal, 34(1), 14-17.
2. Ghosh P., & Sharma A.K. (2018). Comparative Evaluation of Schirmer Tear Test and Phenol Red Thread Test in Canines: An Experimental Study. *Journal of Veterinary Science*, 19(4), 543-547.
3. Hargis A.M., & Drobatz K.J. (2017). Diagnosis and Management of Keratoconjunctivitis Sicca in Dogs and Cats: A Review Article. *Veterinary Clinics: Small Animal Practice*, 47(5), 1007-1020.
4. Dwyer C.N., & Lappin M.R. (2015). Ocular Surface Disease in Cats: Clinical Signs and Treatment Options for Keratoconjunctivitis Sicca and Other Conditions Affecting Tear Production and Quality. Journal of Feline Medicine and Surgery*, 17(6), 511-522.
5. Wilkie D.A., & Maggs D.J. (2004). Clinical Assessment of Tear Production in Dogs Using the Schirmer Tear Test and Phenol Red Thread Test: A Comparative Study of Two Techniques in Healthy Dogs and Those with Ocular Disease. Veterinary Ophthalmology*, 7(2), 87-92.
6. Rojas C.V., et al. (2020). Evaluation of Tear Production Tests in Dogs with Chronic Keratoconjunctivitis Sicca: A Multicenter Study on Diagnostic Accuracy and Clinical Relevance. BMC Veterinary Research, 16(1), Article No.: 123.
7. Wilkie D.A., et al.(2000). The Effectiveness of Topical Cyclosporine for Treating Keratoconjunctivitis Sicca in Dogs: A Clinical Study on Long-term Outcomes and Prognosis Factors for Response to Therapy.*Veterinary Ophthalmology*, 3(3), 157-164.
8. Trost K. (2015). Clinical Findings Associated with Aqueous Tear Deficiency in Companion Animals. Veterinary Clinics: Small Animal Practice.
9. Moore C.P. (2018). Role of Environmental Factors on Ocular Health Among Domestic Animals. Journal of Veterinary Science.
10. Tighe S.N. (2020). Comparative Analysis Between Schirmer’s Test Variants Across Different Species. Veterinary Ophthalmology.
11. Hayat, A., & Biricik, H. S. (2014). Measurement of Tear Secretion in Healthy Pigeons by Using the Phenol Red Thread Test. Veterinary Record, 175(23), 594-594.
12. McLellan G.J., & McCulloch M.E.F. (2008). Evaluation of the Phenol Red Thread Test for Measuring Tear Production in Dogs and Cats: A Review. *Veterinary Ophthalmology*, 11(3), 166-170.
13. Trost, K., Skalicky, M., & Nell, B. (2007). Schirmer Tear Test, Phenol Red Thread Tear Test, Eye Blink Frequency and Corneal Sensitivity in the Guinea Pig. Veterinary Ophthalmology, 10(3), 143-146.
14. Holt, E., Rosenthal, K., & Shofer, F. S. (2006). The Phenol Red Thread Tear Test in Large Psittaciformes. Veterinary Ophthalmology, 9(2), 109-113.
15. Sebbag, L., Uhl, L. K., Schneider, B., Hayes, B., Olds, J., & Mochel, J. P. (2020). Investigation of Schirmer Tear Test-1 for Measurement of Tear Production in Cats in Various Environmental Settings and with Different Test Durations. *Journal of the American Veterinary Medical Association*, 256(6), 681-686.
16. Mantyh, P. W. (1983). The Terminations of the Spinothalamic Tract in the Cat. *Neuroscience Letters*, 38(2), 119-124.
17. Uhl, L. K., Saito, A., Iwashita, H., Maggs, D. J., Mochel, J. P., & Sebbag, L. (2019). Clinical Features of Cats with Aqueous Tear Deficiency: A Retrospective Case Series of 10 Patients (17 Eyes). *Journal of Feline Medicine and Surgery*, 21(10), 944-950.
18. Harvey R.G., Harari J., Delauche A.J., eds. Diagnostic Procedures for Ear Diseases of the Dog and Cat. Ames, IA: Iowa State University Press; 2001: 43–79.
19. Strain G.M., Tedford B.L., Jackson R.M. Postnatal Development of the Brain Stem Auditory-Evoked Potential in Dogs. American Journal of Veterinary Research, 1991; 52: 410–5.