Influence of Macrophages on the Rooster Spermatozoa Quality

The goal of this study was to evaluate the occurrence of macrophages in rooster semen and to investigate their impact on the spermatozoa quality. Ross 308 breeder males (n = 30) with no evidence of genital tract infections were used to determine the concentration of macrophages using fluorescently conjugated acetylated low-density lipoprotein (AcLDL). Subsequently, the roosters were divided into two groups on the basis of semen macrophage concentration, and semen quality was compared in two heterospermic samples. We applied computer-assisted semen analysis (CASA) system to determine motility parameters. Fluorescence microscopy and flow cytometry were used to evaluate occurrence of apoptotic and dead spermatozoa. Spermatozoa fertility potential was examined after intravaginal artificial insemination of hens. Eighteen roosters (control group) contained 0.2-3% of macrophages within spermatozoa population and ten roosters (macrophage group) had 10-15% of macrophages. Males from macrophage group had lower (p < 0.05) motility parameters (total and progressive movement, velocity curved line) and increased concentration of dead spermatozoa detected by flow cytometry and fluorescence microscopy (p < 0.001 and p ˂ 0.05, respectively). Differences (p < 0.05) between fluorescent microscopy and flow cytometry in results on spermatozoa apoptosis and viability were observed. No significant difference was found between groups in fertility of spermatozoa. In conclusion, the higher presence of macrophages in rooster semen may have a negative effect on some parameters of rooster spermatozoa evaluated in vitro. Furthermore, our study suggests that flow cytometry allows more precise examination of spermatozoa viability and apoptosis in a very short time compared with the fluorescent microscopy.