Female llamas are induced ovulators, meaning that release of a mature ovum for fertilization is induced by copulation. They do not have an estrus, or heat, cycle. Llamas can be breed any time of year, although breeders prefer to avoid births occurring during the extreme heat and humidity of summer, or during the severe winter months.When the male llama approaches an open female, she may initially resist his advances, but then she will lie down in a kushed position for him to mount her.Actually breeding can last from 5 minutes to over an hour, with 20 minutes about typical. The male will release semen slowly during the course of the breeding. Approximately 7 days after successful impregnation, the female will resist the advances of the male, often to the point of “spitting-off.” Occasionally open females will spit-off a male, and pregnant females may lie down and allow the male to mate. Due to this variability, behavior is not always a conclusive indicator of pregnancy. Breeders can take advantage of progesterone level testing and ultrasounds to reliably determine pregnancy or the source of breeding problems.