Identification of insulin-like growth factor-I in boar seminal plasma and its influence on sperm quality

Abstract

The present research was carried out to investigate the relationships between spermatozoal parameters and concentrations of IGF-I in the seminal plasma of boar. Semen samples (duplicates) were collected from mature boars (n=27). In each ejaculate, the macroscopic and microscopic characteristics were determined. After centrifugation to separate sperm cells from seminal plasma, concentrations of IGF-I in seminal plasma samples were determined by a human-specific immunoassay kit. The mean concentration of the boar seminal plasma (n=54 samples) IGF-I was 1.5±0.2 ng/mL. There was no correlation (p>0.05) between IGF-I with most of the evaluated parameters. There was only a low negative correlation (-0.29; p=0.0331) between the concentration of IGF-I in seminal plasma and the motility degradation rate. This study suggests that IGF-I in the seminal plasma of boars is not related to initial fresh semen parameters. However, the hormone did increase the duration of sperm motility.