Female llamas are ready for breeding from approximately fifteen months of age, depending upon size and development. Males mature between two and three years of age. This is not to say that either may not be ready earlier. Females have been known to conceive as early as six months and males from ten months.
Llamas breed in a prone position and mating may take up to fifty minutes. Mating can be quite vocal with sounds from humming to grunting and orgling. As llamas are ‘induced ovulators' breeding can take place at any time during the year.
Depending upon climate, breeding should be planned so that it does not coincide with the extreme heat of summer or in the middle of cold winters. Gestation averages 350 days and generally a single offspring (cria) is produced. Twinning is rare. Births normally occur during day light hours and the female may be standing, squatting or in a prone position.
Signs of imminent birth include the female moving away from the rest of the herd, repeated kushing and standing up, repeated visits to the dung pile, stretching out sideways and louder more insistent humming. The birth, if a normal presentation, may take anywhere from 10-45 minutes. Unlike many mammals llamas do not lick their newborn clean. The cria are usually walking within an hour and nursing within two hours. The afterbirth is normally passed within four hours. All being well females are generally bred back again in three to four weeks after giving birth and pregnancy can be determined around 35 to 40 days later by veterinary ultra-sound. A good indication of a pregnancy is the female's refusal to breed when re-introduced to the sire approximately two weeks after the initial breeding. She will demonstrate her lack of interest by spitting at the male. This is known as ‘spitting off'. Llamas, alpacas, guanacos and vicuna can interbreed and should be pastured separately to avoid this. A vet can castrate males not intended for breeding.