The effect of a high protein intake on sperm production in boars at two semen collection frequencies

Abstract

A protein rich diet was fed to half of 97 Yorkshire boars maintained at two semen collection frequencies in two experiments measuring sperm production and semen quality. The boars were fed a control diet (12.56 MJ metabolizable energy (ME) per kg, 14.5% crude protein, 0.68% lysine and 0.44% methionine plus cystine) or an isocaloric diet with increased protein content (12.56 MJ ME per kg, 22.2% of crude protein, 1.20% lysine and 0.81% of methionine plus cystine). The sperm collection occurred either three to four or six times in two weeks (low or high collection frequency). None of the parameters were influenced by amino acid supply. The semen collection frequency influenced the number of ejaculated sperm cells ( P < 0.0001). The number of ejaculated sperm cells per day was increased if the semen collection frequency increased. Sperm quality was not influenced by semen collection frequency. The control diet contained enough protein to ensure good sperm production of a boar used for Artificial Insemination.