Alpaca

Fleeced to Meet You!

The alpaca (Vicugna pacos) is a woolly animal native to South America. It is related to the camel and domesticated llama, as well as their wild cousins the guanaco and vicuña. Raised for their valuable fiber, alpacas come in 22 natural colors, ranging from black and white to brown, beige, and grey. Alpaca gestation lasts 355 days on average, or an amazing 11-12 months! A baby alpaca is called a cria. These little tikes weigh about 20 pounds and grow to 120-190 pounds as adults (Smithsonian, 2023). Alpacas live in herds with a strict social hierarchy and communicate using a variety of hums, squeals, and posturing. There are two alpaca breeds, huacaya and suri, which are described in more detail below:

Image from Britannica.com

Huacaya

The vast majority (about 90%) of alpacas are huacaya. The huacaya breed has dense, woolly fleece with much more crimp, or springiness, than that of suri alpacas. Huacaya fiber is also usually shorter, similar to a sheep's.

Image from PacaPics by Wasim

Suri

At less than 10% of the population, suri is the rarer of the two breeds. Interestingly, the allele for their distinctive, lustrous fiber, which forms long, pencil-like ringlets, is dominant in alpaca genetics (Sponenberg, 2010).

Image from Hobby Farms

Hitting the Hay

Like most herbivores, alpacas are continuous feeders. They spend the majority of their time grazing on grass and low-growing bushes. In domesticated settings, they are fed special hays such as orchard grass, since alfalfa (a common feed for cattle) is generally too rich for them to digest. Their diets are often supplemented with minerals to replicate their natural forage in the Andes Mountains (Martin and Bryant, 1989).

A Spitting Image . . .

Now for the real question: do alpacas spit? The answer is yes! Like their famous relative the llama, alpacas spit to ward off unwanted suitors or to establish dominance in the herd. However, their "spit" isn't just saliva. In fact, it's something much stronger (and more effective, although we pity the unlucky recipient) . . .

Image from Middle England Farm

Rumination Station

Alpacas belong to the same taxonomical order as cows, sheep, and goats. However, they were given their own suborder (Tylopoda) because of the unique makeup of their digestive systems. Like ruminants, alpacas and other camelids are pre-gastric fermenters, which means that most of their microbial fermentation takes place before food reaches the stomach. However, whereas ruminants like cows have a four-chambered stomach, alpacas' stomachs have three chambers: C1, C2, and C3, making them a modified ruminant. C1, where most fermentation occurs, is similar to the ruminant reticulorumen, while C2 corresponds to the omasum and C3 to the abomasum or "true" stomach (Vater et al., 2021). Like all ruminants, though, alpacas ruminate, sometimes spending up to eight hours a day chewing their cud. So when an alpaca spits, what it's really hocking is a chunk of half-digested food — yuck! Below is a video of alpacas ruminating (and pooping . . . Fun fact: Alpacas poop in piles, and they'll often wait in line to go to the bathroom!).

Image from Alpacas of Montana

Image from Etsy

Alpac-Anatomy

Alpacas are uniquely adapted to eat and digest the poor forage of their native habitat. During the dry season in mountainous regions of South America, plants become hard and tough, with very little nutritional value, so camelids' skeletons and digestive systems have evolved in specific ways to survive. Along with their highly modified stomachs (described above), alpacas have a special mouth structure different than that of other ruminants. 

First, alpacas have a cleft upper lip. Each half of the lip acts like a finger, allowing alpacas to feel and grasp food with extreme dexterity. Like other ruminants, alpacas lack incisors in their upper jaw, instead having a hard dental pad. However, male alpacas grow sharp canine teeth (called "fighting teeth") when they reach maturity, which they use to fend off other males. The back of an alpaca's jaw is lined with large, flat molars that it uses to grind its food. Alpacas' teeth continue to grow slowly throughout their lifetimes, replacing what is worn away while chewing (Fowler, 2010).



References

Fowler, M. E. 2010. Medicine and surgery of camelids. 3rd ed. John Wiley & Sons, Hoboken, NJ.


Martin, F. S., and F. C. Bryant. Nutrition of domesticated South American llamas and alpacas. Small Rumin. Res. 

doi: 10.1016/0921-4488(89)90001-1 

Smithsonian's National Zoo and Conservation Biology Institute. 2023. Animals A-Z: Alpaca. https://nationalzoo.si.edu/animals/alpaca (Accessed 10 November 2023.)


Sponenberg, D. P. Suri and huacaya alpaca breeding results in North America. Small Rumin. Res. doi: 10.1016/j.smallrumres.2010.05.004


Vater, A. L., E. Zandt, and J. Maierl. The topographic and systematic anatomy of the alpaca stomach. Anat. Rec. (Hoboken) 

doi: 10.1002/ar.24588