Correlations between fertility and the concentrations of proteins, reducing sugars and 17 types of free amino acids in the seminal plasma of Nelore bulls were estimated. The samples were collected from 19 bulls that had high quality semen, according to physical and morphological analyses. The bulls had their fertility scores estimated based on the pregnancy of the females mated to them during three consecutive breeding seasons, either by artificial insemination or by natural breeding. A large variability in the concentrations of the molecules was observed among the samples and a significant correlation coefficient (r= 0.90) between levels of proteins and reducing sugars was estimated. None of the components showed a significant correlation with fertility.
bull; Nelore; seminal plasma; fertility; biochemical composition