Comparison of the Effects of Different TonoVet® Plus Modes on Intraocular Pressure Measurements in Healthy Domestic Pigeons (Columba livia)

Abstract

Objective: The aim of this study was to systematically evaluate Intraocular pressure (IOP) measurements in healthy, conscious domestic pigeons using the four available animal modes on the TonoVet® Plus device. Materials and Methods: Seventy eyes of 35 healthy pigeons were included in the study. IOP measurements were performed in conscious animals, without anesthesia, using the four modes of the TonoVet® Plus device in a randomized order Results: Measurement mode had a statistically significant effect on IOP (p < 0.05). Mean IOP ranged from 8.59±2.22 mmHg for the Cat mode to 15.57±2.04 mmHg for the Rabbit mode. All modes demonstrated excellent reliability (ICC > 0.88), with the Cat mode having the highest (ICC=0.931) and the Rabbit mode the lowest (ICC=0.882). Compared to the calibrated reference value in the literature, the Rabbit mode provided the result closest to the lower limit of the reference range, while the most reliable Cat mode significantly underestimated IOP. Conclusion: None of the available modes in TonoVet® Plus are ideal for pigeons, and mode selection significantly influences the results. The Cat mode, with its highest reliability, is preferred for monitoring IOP changes, while the Rabbit mode, with its highest apparent accuracy, is preferred for scanning against the reference range. However, in both cases, results should be interpreted cautiously within the limitations of the mode. Direct manometric calibration of TonoVet® Plus for pigeons and the development of a species-specific mode are needed.

Keywords

• Avian
• Columba livia
• Glaucoma
• Intraocular Pressure
• Rebound Tonometry
• TonoVet Plus

Supporting Institution

None.

Ethical Statement

Institution: Balikesir University Animal Experiments Local Ethics Committee (BAUNHADYEK) Date: 07.08.2025 Approval no: 2025/7-13

Thanks

None.

Sağlıklı Evcil Güvercinlerde (Columba livia) Farklı TonoVet® Plus Modlarının Göz İçi Basıncı Ölçümlerine Etkilerinin Karşılaştırılması

Abstract

Amaç: Bu çalışma, TonoVet® Plus rebound tonometresinin dört farklı modu (Kedi, Köpek, At ve Tavşan) kullanılarak sağlıklı, bilinçli evcil güvercinlerde elde edilen Göz İçi Basıncı'nı (GİB) sistematik olarak karşılaştırmayı ve her modun mod içi ölçüm güvenilirliğini belirlemeyi amaçlamaktadır. Gereç ve Yöntem: Çalışmaya 35 sağlıklı güvercinin 70 gözü dahil edildi. GİB ölçümleri, anestezi uygulanmadan, TonoVet® Plus cihazının dört modu kullanılarak, rastgele bir sırayla, bilinçli hayvanlarda gerçekleştirildi. Bulgular: Ölçüm modunun GİB üzerinde istatistiksel olarak anlamlı bir etkisi vardı (p < 0,05). Ortalama GİB, Kedi modu için 8,59±2,22 mmHg ile Tavşan modu için 15,57±2,04 mmHg arasında değişti. Tüm modlar mükemmel güvenilirlik gösterdi (ICC > 0,88), Kedi modu en yüksek (ICC = 0,931) ve Tavşan modu en düşük (ICC = 0,882) değere sahipti. Literatürdeki kalibre edilmiş referans değerleriyle karşılaştırıldığında, Tavşan modu referans aralığının alt sınırına en yakın sonucu verirken, en güvenilir Kedi modu GİB'yi önemli ölçüde düşük tahmin etmiştir. Sonuç: TonoVet® Plus'taki mevcut modların hiçbiri güvercinler için ideal değildir ve mod seçimi sonuçları önemli ölçüde etkilemektedir. En yüksek güvenilirliğe sahip Kedi modu, GİB değişikliklerini izlemek için tercih edilebilirken, en yüksek görünür doğruluğa sahip Tavşan modu, referans aralığı ile tarama yapmak için tercih edilebilir. Ancak, her iki durumda da sonuçlar modun sınırları dahilinde dikkatle yorumlanmalıdır. TonoVet® Plus'ın güvercinler için doğrudan manometrik kalibrasyonu ve türe özgü bir modun geliştirilmesi gerekmektedir.

Keywords

• Kuş
• Columba livia
• Glokom
• Göz İçi Basıncı
• Rebound Tonometri
• TonoVet Plus

Supporting Institution

Yok.

Ethical Statement

Kurum: Balıkesir Üniversitesi Hayvan Deneyleri Yerel Etik Kurulu (BAUNHADYEK) Tarih: 07.08.2025 Onay No: 2025/7-13

Thanks

Yok.

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