Seasonal and other factors affecting the sexual behaviour of alpacas

Records of sexual behaviour of 13 male alpacas (machos) and 97 female alpacas (hembras) obtained during three spring (mid-October to early December, n = 96) and four autumn (mid-February to March, n = 98) joining periods were analysed to determine the effects of season and other factors on sexual behaviour. Joining was carried out by introducing one macho to one hembra in a 5.5 m × 7 m pen. In spring, there was a higher frequency of spitting, kicking, and threatening to spit by hembras, the duration of pre-copulatory chases was longer, mating duration was shorter, and a lower percentage of hembras were mated, compared with autumn joining periods (P < 0.01). Sexually inexperienced hembras were more likely to kick, and attempt to escape from the testing pen, but were less likely to spit or threaten the macho, compared with experienced hembras (P < 0.01). Sexual receptivity was related to the performance of spitting, threatening and kicking by hembras, as these behaviours reduced the likelihood of mating (P < 0.001). It was concluded that season and previous sexual experience affected female behaviour at joining, which in turn affected mating activity. In addition, a negative relationship between the time elapsed since parturition of experienced hembras and the likelihood of mating was found (P < 0.001).