Acta Vet. Brno 2020, 89: 291-300
Fresh semen characteristics in captive accipitrid and falconid birds of prey
Artificial insemination (AI) is the most frequently used assisted reproductive technique for captive propagation of rare avian species. As semen quality is critical for reproductive success, baseline data are needed for evaluating and selecting the best male bird donors. To this end, we used computer-assisted semen analysis to assess male eastern imperial eagles (n = 7), northern goshawks (n = 24) and peregrine falcons (n = 20). While imperial eagles and northern goshawks donate ejaculate voluntarily, peregrine falcons required cloacal massage. Eight peregrine falcon females were inseminated with semen from eight males, with fresh ejaculates (15 to 50 µl) applied to the pars uterina of the oviduct immediately after collection and examination. All females were inseminated within 2 h of laying an egg. A fertilization rate of 70% was achieved using this method. Minimum semen characteristics associated with egg fertilization included a semen concentration of 115.12 × 106/ml, 33.52% total motility, 1.92% spermatozoa with progressive motility and 0.17% with rapid motility. Comparative data on spermatozoa concentration and kinematics suggest that eastern imperial eagles concentrate on high quality semen investment at the start of the breeding season, northern goshawks compensate for a decrease in motility-associated parameters with increased semen concentration and peregrine falcons maintain semen production standards throughout the breeding season. Our data show that, in birds of prey, levels of egg fertilization following AI with fresh semen can be almost as successful as after natural mating.
Keywords
Raptors, ejaculate quality, artificial insemination, fertilization rate, endangered avian species conservation.
Funding
This study was supported through the Internal Grant Agency of the University of Veterinary and Pharmaceutical Sciences Brno (Grant No. 232/2017/FVHE). We are grateful to Dr. Kevin Roche for correction and improvement of the English text. The authors also thank Czech Falconry Club members Karel Světlík, Jiří Nejedlý, Jiří Galát, Vlastimil Voráček and Eduard Školoud, along with MVDr. Monika Krajčovičová, Roman Gabura and Filip Weis from the Slovak Falconry Club, for their help with this study.
