Evaluation of Age-Dependent Sperm Morphometry in Gloster Canaries via CASA System

Abstract

The canary is a small passerine bird of the finch family. Canary spermatozoa are also morphologically similar to many other songbird species. In this study, the morphological characteristics of Gloster canary spermatozoa of different age ranges were examined, and the length values of the parts forming the spermatozoa were compared. The study used ten active Gloster canaries between the ages of three (Trial-1) and four years (Trial-2). Semen samples from 3-year-old canaries in the study were evaluated, and morphological segment lengths were recorded. In the study, to avoid individual differences and make homogeneous measurements, semen samples were retaken from the same canaries one year later during the breeding period and evaluated. However, since the statistical average result was obtained in the study, the canaries were compared as a whole, not individually. Semen was collected from each bird and fixed in a 5% formaldehyde solution. Collected semen samples were evaluated in terms of head length, total flagellum length, acrosome length, and nucleus size at 20× magnification in the computer-assisted CASA system for morphological examination. As a result, it was observed that the head and flagellum length in domestic canary spermatozoa showed an inverse relationship with age. © 2025 Chulalongkorn University Printing House. All rights reserved.