Congenital defects in llamas

"Congenital" means "present at birth."

Some congenital defects are hereditary, some are not. Some are actually both — having a hereditary component, but they must also have an environmental influence (trigger) before they can manifest.

Very few formal scientific studies have investigated congenital defects in llamas, and none to date have reached a full conclusion about the origin of any of these defects. Observation of occurance in related and unrelated individuals makes it clear that some defects are certainly genetic.

At least one private (unpublished) study has shown strong evidence exists for DNA damage (mutation) in a llama parent with subsequent eqpigenetic heritabiity: Progeny inherit the defect from the parent alone, but that parent's ancestors are unaffected and cannot produce defective offspring unless exposure to the mutagenic agent is ongoing.

 

Serious congenital defects (lethal, no surgical correction possible):

 

Serious congenital defects (lethal if not surgically corrected)

 

Nonlethal congenital defects (surgical correction not required for survival)

 

Congenital defects that appear to have an environmental or teratogenic cause, perhaps with a hereditary component

 

Congenital defects with cause as yet undetermined in llamas

 

Congenital differences that are hereditary and are NOT defects

Most of these differences are listed as serious and unacceptable defects by the show association and/or the lama registry. In reality, they do no harm to the llama nor do they significantly change a llama's ability to perform functions for humans. The reason for blacklisting these variations is clearly political. Most breeders would not want these traits their breeding herds for one reason only -- to improve sales potential.

 

Frequency of congenital defects in llamas

When llamas' popularity as an "investment" surged, it was widely stated that llamas had no hereditary defects. Once it became obvious this was not true, the PR line changed to llamas have fewer defects than other livestock. In actual fact, some defects are more common than in other livestock, some occur at a similar rate, and others occur rarely.

In general, duplication errors are more common in llamas (ie, extra digits, extra canines, double cervix) than in other species. Because all lamas (as a genus) all have double upper canines, this prediliction may have originally been a hereditary advantage.

Choanal atresia occurs only in llamas and in humans. Choanal atresia is the most common lethal congenital defect in lamas.

Heritable dominant defects (such as malconformed and gopher ears) and inherited undesirable traits (such as blue eyes) are largely found in the unregistered, "cria mill" and "backyard breeder" portions of the gene pool, where the parental selection bar is low or nonexistant. It does pay to screen breeding stock for known hereditary defects, and to purchase registered stock (with known ancestry) from responsible breeders whose goals include the overall health of the gene pool.

Farms that don't provide good nutrition based on the specific needs dictated by their own locale eventually see increasing rates of birth defects associated with malnutrition, such as rickets, carpus valgus, poor vigor at birth, low birth weights, decreasing adult size, and low fertility.

Farms that limit or eliminate environmental, ingested, and injected exposure to chemical, drug, and feed additives during pregnancy statistically experience far fewer congenital defects of certain types.