Genetic Health Screening for Boxers in a Breeding Program

[Bers]

Source: http://www.americanboxerclub.org/health-screening.html

RECOMMENDATIONS FOR HEALTH SCREENING OF BOXERS
IN BREEDING PROGRAMS

TESTING AND REPORTING GUIDELINES
ABC HEALTH & RESEARCH COMMITTEE

Use and interpretation of tests should be in consultation with your veterinarian or veterinary specialist. These guidelines will be updated as further knowledge is gained.

Condition Tested: Hip/Elbow Dysplasia
Test Used: Radiograph/Radiograph
Minimum Age: 2 years/6 mos.
Frequency: Once/Once
Reported As: OFA#/PennHip%


Condition Tested: Hypothyroidism
Test Used: Thyroid Panel2
Minimum Age: 2 years
Frequency: Annually for Breeding
Reported As: date tested**


Condition Tested: Aortic Valve Disease
Test Used: Auscultation / Doppler1
Minimum Age: None
Frequency: None
Reported As: date tested**


Condition Tested: AS / SAS
Test Used: Auscultation & Doppler Echocardiogram1
Minimum Age: 24 mos. 1
Frequency: Once by Echo
Reported As: date tested**


Condition Tested:
Boxer Cardiomyopathy1
Test Used: Holter Monitor
Minimum Age: 12 mos.
Frequency: Annually for Breeding
Reported As: date tested**

Heart disease can be inherited or it can be caused by bacterial, viral or parasitic agents these are NOT inherited. The damage appears the same in some cases. A screening program can help determine the origin.

All hearts should be ausculted at each veterinary visit. This is particularly important prior to any surgery, including ear cropping. If a murmur is detected the dog should be evaluated to determine the cause and significance of the murmur. Murmurs may be innocent (“flow” murmurs) or may be an indication of structural heart disease such as aortic stenosis, sub aortic stenosis, septal defects or defects of the mitral, tricuspid or pulmonic valves. Echo with Doppler measurements can accurately find and diagnose the origin of murmurs which cannot always be heard or reliably pinpointed by auscultation alone.

1. Maximum flow values have recently been reevaluated and raised to 2.4 IF there is no evidence of structural causes. The cardiologist should determine if the flow value for an individual Boxer is of concern. Current information is that AS/SAS may develop upon sexual maturity in dogs that were previously tested clear, thus the new recommendation for 24 mos. minimum age. Boxer Cardiomyopathy is a complex condition that is still under study.

2. Thyroid panel must include the following tests: TGAA (Thyroglobulin auto antibodies), Total T4AA, Free T4AA (by equilibrium dialysis), cTSH. (Optional tests include T3 and free T3)

3. Because these results can change over time, or because the age at testing may be significant, it is essential to list the date of the most recent test in each case. There are no normal values for some of the recommended tests, and there can be differing opinions between experts in the field.

This post was contributed by Julia (BoxerWB)

[Bugsys Mom]

Thanks, I will need to know that in the furture and it clears up alot of confusion when looking for a responsible breeder.

[ltournat]

Thanks, I will need to know that in the furture and it clears up alot of confusion when looking for a responsible breeder.

Ditto...that will be useful when and if I get a new puppy!

[BoxerPerson]

Very informative...Thanks Julia and Amber.

[*Jen*]

Thank you that is a great post.

[Hobo]

You know I saw this before but I think when ever I go to the dog park I am going to put a copy in my pocket and when someone starts talking to me about breeding. 

"I am going to be like you know, it is funny you ask that I was doing some research today and just happen to have some info in my pocket"

Just do it all non-offensive like.

[*Jen*]

  Whoever you give it to i would love to see there faces!!!

[fairview Boxers]

You need to also carry a listing of how much each test costs.....in your area!    and take a picture of their face...

[Lisa]

I'm confused about the heart diseases in Boxers.  Are there just the three shown on this list?  Is a Doppler different from an echocardiogram?  If I get Koda an echocardiogram when he is two years old and the results are good, does that mean he's cleared of Aortic Valve Disease and AS/SAS for the rest of his life?  Is Boxer Cardiomyopathy1 the same as ARVC?

[Hanna Banana]

Here is the link for the Health Index of the ABC site -

http://www.americanboxerclub.org/healthtbc.html

There are two tests for the heart - an Echcardiogram and Holter -  A doppler descripes the type of Echo being done - and Echo is basically an ultrasound of the heart which determines if the heart is contracting properly. 

http://en.wikipedia.org/wiki/Doppler_echocardiography

A dog can pass any health test at two, but does not always mean they will remain clear of anything  - Echos are normally recommended to be done once esp if the flow rate is low.  However if the flow rate is higher then it is recommended to check again down the line.   Echo normally detect for AS/SAS, but can also provide other information  -

http://www.vetgo.com/cardio/concepts/concsect.php?sectionkey=4&section=Echocardiography

ARVC is detected via a holter -  and the measurement of VPCs in a holter reading.  Many breeders holter every couple of years esp if the dog is involved in a breeding program.

http://www.americanboxerclub.org/boxer_cardiomyopathy.html

[Newcastle]

I'm confused about the heart diseases in Boxers.  Are there just the three shown on this list?

There are two main heart diseases that affect Boxers, AS/SAS and ARVC.  Boxers can have many other heart disease, of course - pulmonic stenosis, dilated cardiomyopathy, mitral valve dysplasia, tricuspid valve dysplasia, etc. - but AS and ARVC are the two most common.

Is a Doppler different from an echocardiogram?  If I get Koda an echocardiogram when he is two years old and the results are good, does that mean he's cleared of Aortic Valve Disease and AS/SAS for the rest of his life?

A Doppler is an "enhanced" echocardiogram, but the terms are often used interchangeably.  Most cardiologists will tell you that no murmur at a year of age means the dog is free of AS (or other valvular diseases); the ABC goes beyond that as do may breeders, but most will say that a clear Doppler at two years of age means the dog is free of AS.  (Some repeat Dopplers every few years, but I've yet to hear of one that was cleared at 1-2 years of age and developed AS later; flow rates may have increased with time, but the physical changes to the heart did not develop.)

Is Boxer Cardiomyopathy1 the same as ARVC?

LOL - yes, actually that "1" is supposed to be a footnote, but it didn't translate in the copy/paste process.   Some people are calling the gene Dr. Meurs discovered the "ARVC-1" gene (or the "Meurs ARVC gene" or "ARVC-A" or something similar) to clarify that the gene is one of potentially many related to ARVC in Boxers, and not the one and only.

[Missy/Precious mom]

Thanks Jen for your clarifications and explanations.

[Lisa]

I'm confused about the heart diseases in Boxers.  Are there just the three shown on this list?

There are two main heart diseases that affect Boxers, AS/SAS and ARVC.  Boxers can have many other heart disease, of course - pulmonic stenosis, dilated cardiomyopathy, mitral valve dysplasia, tricuspid valve dysplasia, etc. - but AS and ARVC are the two most common.

Is a Doppler different from an echocardiogram?  If I get Koda an echocardiogram when he is two years old and the results are good, does that mean he's cleared of Aortic Valve Disease and AS/SAS for the rest of his life?

A Doppler is an "enhanced" echocardiogram, but the terms are often used interchangeably.  Most cardiologists will tell you that no murmur at a year of age means the dog is free of AS (or other valvular diseases); the ABC goes beyond that as do may breeders, but most will say that a clear Doppler at two years of age means the dog is free of AS.  (Some repeat Dopplers every few years, but I've yet to hear of one that was cleared at 1-2 years of age and developed AS later; flow rates may have increased with time, but the physical changes to the heart did not develop.)

  Thanks for all the info.

So what is Aortic Valve Disease?  I'm wondering why it's recommended to be tested for if it's not common.

I'm glad to know that getting Koda an echocardiogram at two years can "clear" him for life so I don't have to worry about AS/SAS affecting him anymore at least.  I feel like the money spent on his ARVC DNA test was pretty much a waste and would have been regardless of the outcome, aside from contributing to research, and know that I will need to keep holtering him every year or so for his entire life in case he does have ARVC so I can get him on meds, reduce strenuous activity, etc.

[Lisa]

Based on my research and the above recommendations saying "none" for minimum age of and frequency of testing for Aortic Valve Disease, I am thinking AS and SAS are types of AVD.  I'm not sure why AVD is listed separately as if there are three heart diseases to test for instead of two though.

[Newcastle]

I am thinking AS and SAS are types of AVD.

Yes, sort of. AS is an aortic valve disease; SAS is technically subvalvular aortic stenosis, which is just below the aortic valve, but probably would be classed as AVD by all but the stickliest sticklers.

I don't know why all three are listed, either; I'm hoping this document will be updated and streamlined/cleaned up a bit soon.  I sent a proposal to the Committee but I wasn't in KY yet when they had the meeting, so wasn't able to defend it.