The female alpaca reaches sexual maturity between 10 and 18 months of age. However, most veterinarians recommend that females reach two-thirds of their mature weight before being bred.
The male alpaca is unable to breed until adequate testicular growth has occurred and the penis is free from its attachments, usually at 2-1/2 to 3 years of age.
Alpacas are induced ovulators. This means that unless they are mated, the female does not ovulate. The physical act of breeding causes ovulation to occur.
Females do not come into heat, but have a cycle of a different sort--hormones in the female alpaca stimulate both follicles within the ovary--The mature follicle forms a corpus luteum or CL that can be seen in an ultrasound and its size can indicate the readiness of the female to become pregnant.
To avoid the expense, alpaca breeders mate at fourteen day intervals. A female who is "ready" will sit in the "cushed" position. The male makes a distinctive "orgling" sound during the mating. When the female is pregnant, she will not be receptive and will kick or "spit" off the male.
Because females can be bred at any time (an alpaca vet can determine the growth of the CL and predict the "best" day for breeding.),males and females are most often kept in separate pens, in order to control who is bred when. Breeding can be done by selective breeding or pasture breeding. In selective or "hand" breeding, the dam and potential sire are put in a pen together. In pasture breeding, the male is put in a pasture with several females. In the US, pasture breeding is rare.
The gestation period for an alpaca is approximately 11 months, producing only one cria (alpaca baby). Crias are often born between 9 am and 2 pm and usually without assistance. Rarely are crias born after 2 pm. Normal, healthy crias, weighing between 14 and 20 pounds, are standing within an hour of birth and nursing shortly after that.
You can watch two videos of alpacas being born on our Alpaca Birthing page.
Because alpacas are herd animals, when a cria is born, everyone else in the herd has to get a look and welcome the new cria to the farm.
At Big Meadow Creek Alpacas, we take the dam and cria (and the placenta) into the Washington State University Veterinary School to be checked within 24 hours of birth. The dam is checked to make sure that there were no tears or other problems created during birthing. The crias are also checked carefully and blood is drawn for both IGg and BVD testing and to use for genetic identification during registration with the Alpaca Registry.
Females can be bred within a week or two after giving birth. The crias are weaned, generally, at six months or at least 60 pounds.
The picture above was taken at Janus Alpaca & Fiber when I took three huacayas up for breeding with three of their males.
We used a small pen and had the three females ready for breeding in the pen. We brought in the macho who was to breed to the one "experienced" dam (Black Satin Sheetz--in the front) and the breeding started immediately.
We then brought in the macho for Caramel Swirl and then the macho for BMCA Double Stuff. This type of "threesome" is not particularly "normal." It's a shame I don't have a video with sound!
Conscientious alpaca owners weigh their crias daily, watching to see that the crias are gaining weight. With 15 crias born on the BMCA farm in 2009, the crew would load the crias into the trailer to bring them to the barn to be weighed--here's what a trailer full of crias look like!