Quantitative sperm characteristics of Tankwa goats with special reference to hyperactivated motility

A. Ngcauzele, G. van der Horst, A. Kotze, T. Jonker & L. Maree

Department of Medical Bioscience, University of the Western Cape, P/Bag X17, Bellville, 7535, South Africa; National Zoological Garden, South African National Biodiversity Institute, PO Box 754, Pretoria, 0001, South Africa; Genetics Department, University of the Free Sate, PO Box 339, Bloemfontein 9300, South Africa; Northern Cape Department of Agriculture, Land Reform and Rural Development, Private Bag X9, Jan Kempdorp, 8550, South Africa

Abstract: Computer-assisted semen analysis (CASA) is an automated and objective method of evaluating structural (e.g. morphology) and functional sperm parameters (e.g. motility and hyperactivation). Sperm hyperactivation is essential for successful fertilization and is thus an important aspect in determining the fertility potential of a male. In the current study, CASA was used for standard semen analysis and for comparison of the ability of phosphate buffered saline (PBS), BO sperm wash (10 mM caffeine), 4% lignocaine, and 5 mM procaine hydrochloride to induce hyperactivation in Tankwa goat spermatozoa. Twenty-nine ejaculates were collected from randomly selected male goats by electroejaculation. Although none of the four media affected percentage total sperm motility, lignocaine caused a significant decrease (P >0.05) in percentage progressive motility. Exposure to procaine resulted in an increase in swimming speed (P ≤0.05) and star-spin motility tracks, which are typical of sperm hyperactivation. Using PBS and procaine motility data from individually selected spermatozoa, receiver operator characteristic curves were constructed to distinguish the kinematic parameters employed as cut-off values for sperm hyperactivation. PBS and BO sperm wash did not induce hyperactivation (0.1 ± 0.2% and 0.04 ± 0.2% respectively), while lignocaine induced little hyperactivation (3.4 ± 3.0%) and procaine hydrochloride had the highest percentage hyperactivation (25.3 ± 13.6%). The large variation in hyperactivation (0–54.5%) may reflect inter-individual differences in sperm quality among these males. This study indicated procaine hydrochloride was the most promising hyperactivation-inducing medium for Tankwa goat spermatozoa and should be considered for similar assessments in other animal species.

See full article here

South African Journal of Animal Science 2020, 50 (No. 5) – DOI: http://dx.doi.org/10.4314/sajas.v50i5.6
Submitted 28 January 2020; Accepted 4 July 2020; Published 26 October 2020