Evaluation of reproductive function of male laboratory animals under radiation and chemical exposure in small doses

Introduction.Today, due to the growth of idiopathic male infertility, the problem of the impact of chemical and physical factors on the reproductive function in men remains very relevant.Studies on the effect of radiation and hexavalent chromium on male fertility in small doses deserve special attention.Literature data on gonadotoxicity and embryotoxicity under exposure to factors in small doses are very contradictory.

Materials and methods. The experimental study was conducted on sexually mature BALB/c mice and Wistar rats of both sexes (a total of 189 animals). The animals were divided into groups according to the received dose of training and potassium dichromate. In mice, group 1 was a control, group 2 consisted of males who received a dose of 0.25 Gy, and group 3 received a dose of 0.5 Gy. In rats, group 1 was a control, group 2 consisted of males who received potassium dichromate (K₂Cr₂O₇) at a dose of 0.028 mg/kg, and group 3 – at a dose of 0.28 mg/kg for 48 days. The state of spermatogenesis was assessed in smears from testicular cell homogenate. To analyze embryonic losses, experimental animals were mated with intact females.

Results. Analysis of the testicles of animals after irradiation and chromium intoxication revealed the following: a 20% decrease in the relaxation index, an increase in multinucleated cells by 40% (dose 0.5 Gy) and 25% (dose 0.28 mg/kg), in aberrant germ cells by 1.5–2 times (dose 0.028 mg/kg and 0.5 Gy, respectively), and an almost 2-fold increase in the number of spermatids with micronuclei. The number of spermatozoa with abnormal heads increases: by 15–20% with irradiation and by 1.5–2 times with chromium intoxication. Mating of experimental males with intact females indicates an increase in the overall embryonic mortality in fetuses by 1.5–2 times with chromium intoxication.

Limitations. In the study, when using the quantitative cytological express method in assessing spermatogenesis disorders under the influence of radiation and xenobiotics in small doses, there are no data on remote effects (90–120 days), which would allow determining the prognostic significance of these indicators in solving reproductive problems.

Conclusions. For the first time, based on quantitative, morphological indicators, the degree of spermatogenesis impairment and the level of embryonic losses during irradiation and chromium intoxication in low doses were shown. The most pronounced degree of spermatogenesis impairment during chromium intoxication leads to a higher level of embryonic mortality.

Compliance with ethical standards. The experimental study was approved by the Bioethics Committee of the Institute of Plant and Animal Ecology of the Ural Branch of the Russian Academy of Sciences (protocol No. 13 dated 03/12/2025).

Conflict of interest. The authors declare no conflict of interest.

Funding. The study was carried out within the framework of State Assignment to Institute of Plant and Animal Ecology (No. 122021000085-1).

Received: April 28, 2025 / Accepted: June 26, 2025 / Published: December 19, 2025

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