Ultrasonographic Evaluation of the Corpora Nigra in the Eyes of Turkmen Horse: Assessment of Echogenicity, Dimensions, and Volume

Document Type : Original Article

Authors

1 Department of veterinary Clinical Sciences, SR.C., Islamic Azad University, Tehran, Iran.

2 Department of veterinary Clinical Sciences, SR.C., Islamic Azad University, Tehran, Iran

3 Epidemiology and Zoonosis Division, Department of Food Hygiene, Faculty of Veterinary medicine, University of Tehran, Tehran, Iran

Abstract

The aim of this study was to evaluate the ultrasonographic characteristics of the corpora nigra in the eyes of Turkmen horses, including echogenicity, dimensions, and volume. In this study, 30 healthy Turkmen horses (19 mares and 11 stallions) were categorized based on age and sex into four groups: immature stallions, mature stallions, immature mares, and mature mares. A transpalpebral technique was used for the ultrasonographic evaluation of the eye, and the length, volume, and area of the corpora nigra were measured. Ultrasonographic examination of the corpora nigra in Turkmen horses revealed that, in terms of echogenicity, all observed structures exhibited a hyperechoic appearance and generally appeared as round or oval bodies with defined borders and margins, located adjacent to each other. The results of the analyses showed that the mean length and area of the corpora nigra were smaller in younger males compared to females, while in older males, these values were equal to those in females. The statistical test indicated significant differences in the length and area of the corpora nigra based on age, but no significant differences were observed between the two sexes overall. The volume of the corpora nigra was the same in all groups, regardless of age or sex. This study aims to establish reference values and improve the understanding of these structures for clinical evaluations and management of ocular diseases in this breed.
 
 

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References

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Journal of Veterinary Laboratory Research
Volume 17, Issue 2 - Serial Number 28
October 2025
Pages 249-257

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