New Approaches to Predict the Sperm Quality by the Spermatozoal miRNA Content in Fish: A Review

The survival of the progeny and fertilization success depend on high-quality mature spermatozoa containing DNA and coding and non-coding RNAs besides the female gamete quality. Sperm cells and gonads in fish contain different RNA classes. It is possible that the development of fish could be affected by miRNA and/or other non-coding RNAs being abundant in Teleost fish and having important functions. Studies about the presence of miRNA in some fish species (e.g. Danio rerio, Salmo salar, Carassius auratus, Cyprinus carpio) showed that sperm motility is regulated by miRNA. Nevertheless, limited knowledge and several hypotheses have been presented about classes and content of RNAs in fish spermatozoa. More research about the effects of miRNA on fish reproduction and sperm quality are needed for population, aquatic ecosystems, and broodstock management, and the evaluation of molecular sperm quality parameters with miRNA could be used together with traditional techniques.