Development of a non-terminal technique for sperm collection in Wistar rats to study the influence of environmental factors on reproduction

Background. In more than 30 % of cases, infertility is attributed to male factors. The diagnosis of male infertility is based on semen analysis. The assessed semen parameters include sperm concentration, motility, and morphology. Laboratory animal models enable the study of various biological processes, including the effects of external and internal factors on reproduction processes. However, to date, there is no simple, safe, non-terminal method for sperm collection in animals.

Aim. To develop a non-terminal sperm collection technique using optimal electrical stimulation parameters in Wistar rats to study the influence of environmental factors on the reproductive function.

Materials and methods. The study was performed on 30 male Wistar rats weighing 280–300 g. For sperm collection, a rectal electrical stimulator was used to obtain ejaculate. A hemocytometer and two types of microscopes were used for sperm analysis and counting: a Micromed P-1 LED (Russia) and a Levenhuk D90L LCD digital microscope (China).

Results. All animals were divided into 6 groups of five individuals each, according to the electrical stimulation protocol. All stimulation protocols resulted in erection in all groups of animals. However, the safest and most cell-saving method was found to be rectal electrical stimulation of the seminal colliculus of rats at settings of 60 Hz and 4 V.

Conclusion. A method for sperm collection in Wistar rats with an optimized electrical stimulation protocol has been developed, enabling the study of various factors affecting male fertility.

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