Choanal Atresia in the Lama World

by Dawn Blessing

A reprint of: Las Crias Ranch & Alpaca Newsletter Issue # 12

* The purpose of this newsletter is to share some of the experiences and information which may be helpful to those considering joining into this wonderful lifestyle.  The opinions expressed herein are mine (ours), unless otherwise stated. All thoughts, comments, or requests about specific topics are very welcome!

Anyway, this week I'd like to address something that is getting to be a really big issue. We join many other farms in the feeling that this is a big probelem that is going to get bigger if all of us don't take a definite stand and do something about it. I'd also like to mention that we, at Las Crias, have a zero tolerance stance to this.  It is called Choanal Atresia or CA .

**First, what this is:

Choanal Atresia (CA) is a congenital disease where one or both of the nasal passages are blocked by a bony growth.  The animal is born with it, and it's usually evident pretty quickly, as the cria usually dies shortly after birth due to suffocation.   If the affliction isn't as severe, the cria will breathe differently (mostly through the mouth).  They also have great difficulty nursing due to the breathing.  The potential for getting milk into their trachea and lungs (aspiration pneumonia) is increased causing another life threatening condition.  Furthermore, the cria swallows large volumes of air which interferes with their normal gastro-intestinal function.  In most CA babies, the nostrils appear normal.  The owner may first suspect CA when the cria tries to nurse.  If the cria has a complete CA, euthanasia is usually the appropriate choice.  In the case of a partial or unilateral CA, no treatment may be necessary for the animal to lead a fairly normal life, however, such an animal should be removed from the breeding program.  Severity varies, depending on whether it's on one or both sides, and is generally not surgically correctable, although they have some surgically "corrected" cases in the Llama Research herd at Oregon State.   A test for CA that vets perform on new crias during their first health exam is either put a mirror up to the nose of the cria to see equally sized fog patches, or they will place their thumb over one nostril at a time to check breathing ability and ease.

**What we feel each of us, as breeders and buyers, can do about this problem:

First of all, a carrier is an animal who does not show symptoms, but is a parent of a CA cria.   The evidence of a certain alpaca being a carrier is more appearant for a male as they are able to sire numerous crias in the same timeframe that a female is only able to deliver one.  It is still uncertain how many genes it takes to cause a CA birth. It does seem to be a multiple gene problem, but the combination necessary is still unclear.  Although it is said that all alpacas carry this CA genetic to a certain degree, the general consensus is that this has been brought about by excessive inbreeding in South America (mostly in Peru) to keep white fleece a strong trait in the herds.   Colored fleece there is undesireable.  With that in mind, this may point to CA being less frequent in colored alapcas, but with more and more white alapcas being bred to colored, this thought may quickly disappear.

There seems to be two definite opinions about CA here in the US.   One is that since 25% of alpaca deaths in South America is caused from CA, it is just viewed as "one of those things" that happen to alpacas.  The information about the known carrier alpaca(s) is generally not voluntarily disclosed to purchasers by the breeders attempting to sell breedings or the animals themselves.  Since they feel this is not a problem, they wrongfully take it upon themselves to make the same decision for their buyer.  The other opinion is that all information, genetic and otherwise, should be disclosed to the buyer so they can make in informed, educated decision about the purchase or breeding they are contemplating.  Also, that CA is a very big problem and any known CA carrier alpacas should be totally eliminated from the gene pool. If there have been get from these alpacas, the owners should be notified that their alpaca's parent (sire) has contributed in producing a CA cria and is considered a known carrier.  Notification to owners of females who have been bred to known carrier males should be done as well. Some sort of compensation would need to be offered.  We all understand that this kind of "fessing up" is difficult and, in most cases, costly to do, but is in no doubt the most responsible and ethical thing to do.  It is very encouraging when we find more more and more breeders who support the second opinion!!

In Australia, they do consider CA to be a genetic problem, and totally eliminate the sire and dam who produce it.  Alpaca owners and breeders, who have smaller alpaca herd numbers than the US, have taken care of their few CA problems they have had by promptly gelding the males who sired the CA cria (and use them as teasers), and culling (not moving or selling) the females who bore the afflicted cria.

In comparisson to the llama herds, alpacas' problem with CA is in its infancy, but will no doubt become a real epidemic if prophylactic measures aren't taken.  Purchasers need to research bloodlines, and ask breeders point-blank questions about any problem crias what-so-ever that their alpacas, male or female, may have produced.  Call around, ask questions, and read as much as possible about genetic and other defects.  Have an attorney draw up a Rider Statement for the breeder and you to sign regarding these kinds of problems prior to signing a sales contract.  Protect yourself. There is usually no real recourse once the animals are purchased.  Get from carriers may not throw CA cria for some time, which will make you responsible for that problem, not the breeder you bought your alpacas from.  Make sure the breeder is going to be accountable for the alpaca you purchase from them if they are pregnant and happen to have a CA afflicted cria, especially if you eventually find out they did know about a problem and chose not to inform you because of their own views on the issue.  They could try to say that it is not proven that CA is a genetic problem, and you may not be protected with their sales contract.  If they refuse to give you satisfactory answers on the bloodlines you have done research on and found to have a problem, you have the right to not do business with that breeder.  As with any other business, you can "vote with your dollars", and not reward unsatisfactory practices.

**Research and Needs:

There are two components to this project:

a.) Breeding studies - This is the portion that is in place, approved and waiting pending funds release.  This portion runs about $23,000 for a two year period.  This portion of the study will sort out the mode of inheritance - single vs multiple genes, dominance etc. The DNA samples collected in this study will be used to validate the identification of carriers in the second study.

b.) The DNA testing has been discontinued due to the absence of funding.  Unlike the first study, this portion of the research can not be continued on a stop gap basis.  It is suspected, however, that this portion would run $30,000+.  This is expensive complex work and can not be done on the cheap.

The Alpaca Registry (ARI) and AOBA have funded $20,000 for a gene mapping project being conducted by the University of California at Davis (UCD), the group that is the repository for the registry's blood type data.  Gene mapping is the first step in developing an understanding of which genes are linked to which traits (including defects) and therefore the first step in developing a test for genetic defects.  With having only identified 15+ markers it will be another 2 years before the research is completed.  UCD will be able to develop a test to identify genetic defects including CA, Patent Ductus Arteriosus (PDA), AA, polydactly, wry face, Atrial / Ventricular Septal Defects (V/A SD), etc.  This test will cost between $50.00 - $100.00 per test (per geneticist) when completed. The more tests that are run, the lower the cost.  With the lab running ~5,000 blood typing tests annually, the cost is $32.00.  If the genetic marker test is as popular as the blood typing, then the test fee will drop quickly. All UCD is waiting on is complete familes of aflicted animals (any genetic anomolies).  This means blood samples of aflicted animal, sire, dam, and any sibilings (half or full).  They are currently seeking at least 20 complete families ASAP. More will be needed in the future.  Currently the lab will run the DNA typing and testing for aflicted families for $15.00 per animal.  The data results will not be available for some time though.

**Additional reading, if you desire:

There is a very nice article on CA on page 64 in the Alpaca Registry Journal (Summer Fall 1996).  It's very authoritative, authored by Dr. Brad Smith and Dr. Karen Timm of Oregon State. Dr. Brad Smith may be able to recommend additional reading sources, and offer more information on this issue.

**If you have a CA carrier, there's a way you can help :

1. CA carrier alpacas have been bred, to my understanding, by vets at universities to try to find out what the genetic inheritance is but they are not being bred for sale or for the breeding population, obviously.  They are always looking for more known carriers to be donated to thier efforts to figure out what causes CA and how to stop this very real problem. A positive way to take part in this research is to donate the known carrier to the Institution.  I'm very sure it is tax deductable (be sure to check that out with your tax preparer).

2. Regarding any congenital anomalies in camelids, Jennifer Bowman has started compiling data and putting together a web site for the defects.  A form for completion can be forwarded to anyone interested.  5-8cc of anticoagulated blood will also be needed to be shipped to UCD Serology Lab. For more information please email Jennifer privately at : salrllamas@tgi.net

**Fund Raising attempts:

They do exist, but mostly on a small scale with the money raised going toward designated institutions.  For example - GALA, the Greater Appalachain Llama and Alpaca Association, recently raised over $9,000 designated specifically for research projects.  On a smaller scale, NEAOBA, the New England Alpaca Owners and Breeders

Association is holding a raffle type fundraiser at our upcoming event in May in hopes of raising some serious funds.  Cindy Lavan at Chase Tavern Farm Alpacas is coordinating it, and welcome people to participate.  Please contact her privately at: (ctalpacas@maine.com) if you would like to donate a raffle item.  All monies raised will go to reasearch, that she promises.  They are focusing this raffle on a general scale so that the "average" Joe or Mary can purchase the tickets. So raffle items such as alpaca made products, alpaca gift items would be key.  They are also thinking of raffling off a free breeding to alpaca folks as well, those raffle ticket prices will be higher.

**This is by no means all inclusive of the information. More digging needs to be done by all who are interested, and definite points of view need to be taken then consistantly adhered to about this issue.  If we all work together to fund research and irradicate the known problems in our individual herds, this problem can be kept to a minimum and healthier crias and incomes will result.  We need to become part of the cure, not turn our heads and become part of the cause.