The in vitro effect of kanamycin on the behaviour of bovine spermatozoa
The use of antibiotics is a common part of animal biotechnologies. Especially, the use of antibiotics in semen extenders is necessary. However, the effect of antibiotics on the spermatozoa structure and function is still not completely examined. Therefore, the aim of our study was to investigate the effect of kanamycin on bovine spermatozoa at concentrations of 80 and 160 µg/mL during the 24 h in vitro cultivation. Semen samples were collected from clinically healthy Holstein-Friesian bulls. At times of 0, 2 and 24 h the motility assessment, mitochondrial activity, acrosomal and membrane integrity evaluation were performed. The sperm motility was measured using the Computer-assisted sperm analysis (CASA). Mitochondrial activity was evaluated through the Mitochondrial Toxicity Test (MTT). The acrosomal status was determined using the fast green/rose bengal staining on slides. Similarly, the membrane integrity was analysed using the eosin-nigrosin staining. Our results revealed the dose- and time-dependent effect of kanamycin under the in vitro conditions. In conclusion, the selected concentrations of kanamycin may have adverse effects on the motility, mitochondrial activity, acrosomal and membrane integrity during semen processing. Considering the relatively low concentrations used, we do not recommend to use kanamycin as a supplement in bovine semen extenders.