Daily sperm production per gram of testis per day following 10ρg (A), 1ηg (B) and 1µg (C) doses after 2, 4, 6, 8, 10 and 12 days of kisspeptin treatment. Daily sperm production decreased significantly at all kisspeptin doses after 8, 10 and 12 days of treatment. Values are expressed as mean ± SE (n=7). *p<0.05, **p<0.01, ***p<0.001.