IMPACT OF TILMICOSIN ON THE RABBIT SPERMATOZOA MOTILITY AND VIABILITY

Abstract

The aim of this study was to examine the effects of tilmicosin on rabbit spermatozoa viability and motility parameters during short-term in vitro incubation at 37°C. Semen samples were collected from adult New Zealand White rabbits and diluted with eight concentrations of tilmicosin: 0.300, 0.350, 0.400, 0.466, 0.500, 0.583, 0.600 and 0.700 mg.ml–1 (TIL 1 – 8) diluted in the physiological solution. The motility parameters were evaluated using the Computer Assisted Semen Analyzer system (Sperm Vision®) at five time periods: 0, 1, 2, 3 and 4 hours. Cell viability was measured using the metabolic activity MTT assay. Immediately at the beginning of incubation significantly higher values of motility (MOT) and progressive motility (PRO) were detected in samples TIL2, TIL5 and TIL7 compared to the control. Significantly lower values of tested motility parameters were observed after 1 and 3 hours of incubation. All concentrations of tilmicosin have no significantly negative effect on the parameters of the MOT, PRO and velocity curved line (VCL) after 4 hours of incubation in vitro at 37°C. Concentration of tilmicosin 0.350 mg.ml-1 has a positive impact on MOT (72.39 ± 15.62%, p<0.001) and PRO (54.28 ± 21.23%, p<0.01) of rabbit spermatozoa after 4 hours of incubation in vitro at 37°C. Supplementation of tilmicosin led to preservation of the cell over all time periods of the in vitro incubation. The results indicate that tilmicosin could be used to semen extenders without negative effects on rabbit spermatozoa motility and viability.