DISTRIBUTION OF BOARS SPERMATOZOA IN MORPHOMETRICALLY DISTINCT SUBPOPULATIONS AFTER IN VITRO EXPOSURE TO RADIOFREQUENCY RADIATION AT 2500 MHz

To the best of our knowledge, this is the first analysis of morphometric parameters for assessing the influence of radiofrequency radiation (RF) at 2500 MHz on spermatozoa subpopulations. The aim of this study was to establish the influence of RF at 2500 MHz in vitro exposed breading boars’ semen on proportions of spermatozoa subpopulations using the principal component (PC) and cluster analysis according to morphometric head and tail parameters. Semen of 12 breeding boars was collected using a manual fixation method. Semen samples of each boar were divided into a control and an experimental sample. The experimental samples were exposed to RF of 2500 MHz in gigahertz transverse electromagnetic chamber for 2 hours at an electromagnetic field strength of 10 V/m. Semen smears were stained using the Spermac method. Morphometric analyses in the control and experimental samples were performed in stained smears by SFORM computer- assisted program. Morphometric size and shape parameters of boar’s spermatozoa (n=1691) were determined. The PC analysis revealed four components with the most important value for each (head length and width, head regularity, midpiece outline). Cluster analysis indicated there were two subpopulations (S1 - spermatozoa of smaller length and larger head width, more regular head shape and smaller circumference of the midpiece and S2 - spermatozoa of longer length and smaller head width, more elongated head shape and larger outline of the midpiece). Exposed boars’ semen samples had a greater proportion of S1 spermatozoa compared to control samples (51.83% vs 48.7%) and a lesser proportion of S2 spermatozoa (47.54% vs 52.47%). The effect of RF at 2500 MHz in vitro exposed breading boars’ semen was manifested in a reduced proportion of spermatozoa subpopulation with the spermatozoa of more elongated head and larger midpiece outline which could decrease spermatozoa motility and fertility potential.