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.

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