Mega Esophagus And Breeders - Page 4

I guess I may look at breeding a little differently. I do understand what Sara is saying about being able to limit DM by testing, but by breeding the gene lives on for another generation. When I was breeding, I was never thinking about just the next litter, but tried to keep in mind what I hoped to produce on down the road. I did manage to breed myself out of GSD in 3 generations, so maybe I'm not the best example to follow.

In the end, there are many health issues facing a serious breeder. hips, elbows, spine, epilepsy, DM, allergies to name a few. This is before even considering character and structure/cosmetic issues.

To breed or advocate breeding of known health isses should not be acceptable to anyone concerned about the GSD as a breed, It does not matter the percentages. Somewhere down the line, some unsuspecting buyer (like the O/P) is going to pay the price in heartache and finances. For that unlucky person, the odds are 100%.

jmo,

Rik 

OK... food for thought here:)

The German Shepherd Dog is said to have come from a balancing of 4 different breed types. What if we find that one type in particular carries the DM gene? By eliminating all DM carriers, breeders could inadvertantly be eliminating a very important piece of the balancing act of breeding.

What other traits might be lost??? Maybe you lose dogs also known for great tracking. Or dogs known to produce social aggression? or lose those known for biddability?

When you focus on one thing; whether sidegait or DM marker.... you are bound to miss out on something.

---Mary

Mary, what specifically has been lost by the mandatory requirement for h/e certification already in place. There are GSD still being produced for any task imaginable for a dog to do. From war dog, LE, to running in circles. And there are still great tracking dogs with good h/e and bred from dogs with good h/e.

The requirement just forced breeders to choose dogs for their purposes from h/e proven dogs. And hips were a much greater concern than DM. I think at one time it was estimated that approx. 50% were not able to certify. 

I really don't know that I've ever seen a great tracking dog dragging it's rear end down the track. I guess it's possible. 

I think limiting to color has done much more harm to the GSD as a breed than any restrictions on health ever will.

Rik

Got to agree with Rik in that selection for non functional traits like colour and TRAD movement can do immeasurable harm to a breed by depleting the gene pool.  A breed such as the GSD also has the added problems of more or less isolated populations within the breed, where various factions select for their own puposes, so any attempts to keep the gene pool from further depletion can only be a good thing.

This idea we have that all defect genes must be eliminated is understandable but flawed in that it can never be accomplished and for the harm that it does by reducing genetic diversity.  The more the gene pool is depleted, the more genetic defects will come to the surface.  And this is not just simple recessive traits that increase in frequency under these conditions, it's also more complex conditions that can be predisposed by increased homozygosity of the MHC gene complex.  So, the more we select to eliminate one disease gene from the population the more likely we are to see other defect conditions appearing.

A new publication here that addresses these issues - 

Traditionally, it has been desirable for animals to “breed true” for the breeder’s objectives, including breed-type and an absence of disease traits. However, the weight of scientific evidence suggests that genetic conformity is not desirable. Genomic heterogeneity has been shown to correspond to improved fertility, production, and vitality in a variety of production animal species (e.g., Sorensen et al. 2008). It is possible for highly homozygous populations to be healthy, if all the alleles that have reached fixation correspond to a healthy state, such as in certain lines of inbred mice. However, the chance of a particular line reaching fixation for healthy alleles (and purging of unhealthy alleles) for every gene is so low as to be unattainable in acceptable dog breeding practice, and so genetic progress in health and welfare objectives must be balanced appropriately against retaining genetic diversity. Indeed, the risk of fixation for unhealthy alleles through genetic drift or close breeding may be higher than previously guessed.

http://www.springerlink.com/content/031825p473055378/fulltext.html

Thank You Pod!!!! Good to see that my old armchair thoughts are not archaic but actually shared in the scientific world!

Back to Mega- E .. I think there needs to be some vid tape addressed here and sound bites if possible. I have seen with my own eyes a puppy with Mega E. I also HEARD a noise when the puppy was running that sounded like wet rubber balloons rubbing against one another.. almost like the sound of a horse running with water/food in its belly.. An observant breeder should be able to identify this anomaly in an otherwise healthy puppy.

The problem with Mega E is not an deformity as some said, its a lack of nerves responding in the muscle of the esophagus. The nerves keep the muscle taught, but if there is either nerve damage or a place where the nerves do not respond , they cannot keep the muscle wall tight and thus a relaxed ( paralyzed spot) pouch is formed. A deformity would mean that the esophagus its self was formed in a pouch, which is not true. There are other un-related problems where a ring is left after birth , which causes constriction to the esophagus, this like undescended testicles can be attributed to hormone issues.

http://www.marvistavet.com/html/body_megaesophagus.html

Just as there are a bunch of different heart defects possible, multible bone malformitys that could happen ( hips spine knees shoulder elbow), so there are other genetic issues as other posters have mentioned- there is no such thing as a perfect ANYTHING and there cannot be . Some things cannot be bred out, infact by reducing the gene pool you will end up with more issues.

Good luck with your puppy OP.

Whisper

Some of you act as if Mega-E and DM are at epidemic proportions and impossible to avoid without "reducing" the gene pool. This is no where close to being fact. mega-e is not common at all. If DM were rampant, then the dogs affected would be much higher. As I said before, in 25 years, I have seen one instance of mega-e, which happened to be in my breeding. I have not yet seen a dog with DM first hand or have knowledge of one.

This is my last comment on this as I know that most people are going to breed what they have regardless of issues and have the excuses to justify. What I question most is that if one is not going to make every effort to breed a healthy, long lived dog first and foremost, then why in the hell do you call yourself a breeder.

Rick Atchley

I had a Mega E puppy in my last litter, she appeared to be perfetly healthy, energetic and  normal but for some strange reason I held her back and refused to sell her, I just kept telling people to ring me back in 3 or 4 weeks and I may have a puppy available, then she stared to vomit after eating and I knew why I had refused to sell her and an xray soon proved why I felt the way I did about this puppy.
Heart breaking to rear a puppy to have to PTS at 6 weeks.

I can say from experience that Ive contacted breeders on an testicle issue after I had dogs back to back with this problem. I contacted ALOT of breeders and only one stepped up to actually tell me she had a puppy with it. I think this is also a genetic issue that could be minimized but breeders continue to  pass this trait on. Why is what I often ask myself? I think its sad that breeders think its ok. Lesser of the evils I suppose. A breeder actually said that to me once. I honestly cant remember the last shepherd Ive had that was sound genetically and mentally. YEARS. Ive been looking for another shepherd since my last one died of a CONGENITAL DEFECT at 6. Not sure though I want to throw the dice again. Had two shepherd rescues one was unsound physically the other a true nut case.

Margaret Im really sorry for your losses. Breeders forget what its like to have a sick friend that you vet for its life only to have the dog die of a defect that COULD HAVE BEEN PREVENTED. I see it often and get angry when I find out the breeder is "respectible". I will say as a footnote in defense of some breeders: Many are not advised of issues when Im asked to take a dog in. The buyer thinks for some reason it was on purpose and bad mouths the breeder. I always tell breeders when there are issues because if the buyer doesnt, then how will be there be change.

Sara, thanks for taking a stand on your position. Unfortunately, its when we think that we can somehow control genetics that we have somehow fallen from the path. JMO