Study of the applicability of I2-COSAN as a preservative for boar semen = Estudi de l'aplicabilitat del I2-COSAN coma preservant del semen porcí

Abstract

Seminal doses need to be preserved in a diluent with antibiotics to avoid bacterial contamination, which can cause infections in the female, affect fertilization and sperm quality parameters, although the need for these doses is not only for artificial insemination, but also for veterinary and human medicine. The increase in antibiotic resistance is a problem that has led to increased research into new antimicrobial compounds that can deal with multiresistant bacteria. In a previous study, the bactericidal activity of metalacarborane I2-COSAN in vitro has been demonstrated. In order to study the applicability of this compound as a preservative for boar semen, the effect of I2-COSAN on the sperm quality of uninfected samples and samples infected with Staphylococcus aureus MRSA and Escherichia coli BLEE, as well as its antimicrobial activity in these samples, was studied in this work. For the study of the impact on boar semen, the effect on motility, viability and morphology was studied through CASA (Computer-assisted sperm analysis). The study of the antimicrobial activity has been carried out by quantifying viable cells at different times (0h, 24h and 48h). The compound does not affect the viability of spermatozoa, but it does affect their motility. A fine-tuning of the protocol has also been done, finding that centrifugation greatly affects sperm motility, which will be applicable in future studies performed with other similar compounds. In the assays carried out to test the antimicrobial effect of I2-COSAN on S. aureus, a similar percentage reduction of bacterial viability was observed in all treatments. As far as E. coli is concerned, no results were obtained, because the bacterium die after 24h in the seminal samples. This indicates that there is something in the boar seminal samples that affects the tested bacteria, being E. coli more sensible than S. aureus. The fact that the compound severely affects sperm motility limits its applicability in the preservation of these samples, so it would be necessary to study other similar compounds, in order to completely refute the applicability of metalacarboranes in the preservation of seminal samples