This research took place in canton Cuenca, province of Azuay, Ecuador, located on UTM 717386 x 9675751, 2 714 meters above sea level, with a mean temperature of 14°C. The study determined the influence of penile spicules on sexual behavior, fertility and sperm quality parameters in cavies (Cavia porcellus), raised on the Ecuadoran highlands. A number of 5 whole males (with penile spicules), and other 5 males with their spicules removedwere included in the study, along with 40 nulliparous females, type A, pelage type 1. The pregnancy percentage of females that copulated with extirpated males decreased 65% in relation to the control group (P<0.05). However, the sexual behavior pattern and sperm quality of the two groups in the study were similar (P>0.05). Therefore, the study concluded that extirpation of the penile spicules has effects on fertility, but not on sexual behavior and sperm quality
