The following letter was sent to the membership of the American Manchester Terrier Club in June 2026, and will be published in the club’s fall 2026 newsletter. In short, all breeders are now strongly encouraged to screen for deafness in Manchester Terriers.
Update from the AMTC Health Committee Chair
By Michelle Barlak
The occurrence of deafness in Manchester Terriers has been whispered about for decades but has never been widely reported. Recently, a few breeders have come forward with information about deafness in their dogs that has resulted in a large number of dogs being tested. The rate at which deafness has been detected recently in the Standard variety is cause for concern, but I have the fullest faith that we can address this as a breed community.
At the most recent AMTC Board meeting, the health committee put forth the recommendation that BAER testing be added to the list of required tests for Standards to receive an OFA CHIC certification, and that it be added to the list of recommended tests for Toys. This was approved unanimously by the AMTC Board and has been submitted to OFA for review and acceptance.
To that end, I have put together the following short-term guidance, which I hope will help us all to navigate this complicated issue. As more information is gathered, we will share continued guidance with the membership.
Recommendations for Breeders
- Testing: Of paramount importance is gathering information through BAER testing. It is the only way to detect unilateral deafness (deaf in one ear). BAER testing for congenital deafness only needs to be done once. Please see more about testing in the FAQ attached to this letter.
- Standards: All dogs should be tested before breeding. All litters from affected dogs or relatives of affected dogs should be tested prior to placement. Puppy owners deserve to be informed if their puppy is unilaterally or bilaterally deaf before placement.
- Toys: All dogs should be tested before breeding. More information needs to be gathered about how this affects Toys and we can only do that through testing.
- Reporting: The only way to tackle this as a community is to share information. The lack of testing and reporting is what got us here.
- All test results (passing and failing) should be recorded in the public OFA database.
- There is no time limit on when test results can be submitted. You can submit test results to OFA at any time, even if you have a 10 yr old dog that was tested 8 years ago. As long as you still have the documentation, OFA will accept the results.
- Research: Health committee members Christina Caridis and Robin Gates have agreed to spearhead research efforts. Be on the lookout for more information.
- Breeding: The OFA recommendation is to avoid breeding affected dogs altogether. I think that is reasonable until more is known. What I do NOT advocate is for the mass-spay and neuter of all unilaterally deaf dogs and their relatives. Canine genetics research grows by leaps and bounds every year. If we all work together, a genetic test could be developed before some of these younger dogs pass breeding age.
I have the same questions as all of you about how much it affects Standards and Toys, where this deafness has come from, and how to breed away from it. I don’t have all the answers but here are my thoughts:
- I urge caution and ask our community to pause before making rash decisions. We need to make informed decisions.
- Pedigree research is important but it’s easy to shift into blame and we need to do our best to be as neutral as possible. Witch hunts will only prevent people from sharing information. We can’t go back and change the past but we can move forward together and continue to make the breed better.
I know we can work together, set aside differences, and protect the future health of our breed. We did it with the juvenile dilated cardiomyopathy study, and we can do it again.
Resources for BAER Testing
BAER Test Sites | Deafness in Dogs & Cats https://lsu.edu/vetmed/deafness/baersite.php
OFA Health Clinics https://ofa.org/health-clinics/
Dog/Canine Health Test Clinic Schedule https://cavalierhealth.org/health_clinics.htm
Note: For more information about BAER testing, and the genetics and inheritance for deafness, please visit https://ofa.org/diseases/other-phenotypic-evaluations/congenital-deafness/
Frequently Asked Questions – Deafness in Manchester Terriers
1. Why wasn’t BAER testing already required if deafness was known to be in the breed?
Per the OFA, “Once included in the CHIC program, the breed-specific requirements are dynamic. As health priorities within a breed change… the breed-specific requirements can be modified to reflect the current environment. If the breed-specific requirements are modified, existing CHIC numbers are not revoked.”
Based on past health surveys (2002, 2018, 2020) and OFA test records, deafness was not widely reported in the breed. However, because it had been documented in the Standard variety, it was listed as an optional test in the 2021 OFA update. One of the purposes of the OFA database is to allow parent clubs and breeders to track, test, and report disease rates through testing. Now that new information is available, the health concerns have shifted, and so have our health testing recommendations.
2. Why was BAER testing added to the CHIC requirements for Standards and not Toys?
At this time, BAER has been added as an optional health test for Toys. We encourage breeders to do all of the health tests listed and share their results through the public OFA database. If we should determine based on this new data that deafness is a prevalent disease in Toys, we can amend the health test recommendations.
3. Why are the health tests different for each variety if they are the same breed?
The only difference lies in the emphasis placed on specific tests, which are categorized as either required or recommended, depending on the variety. However, it’s important to note that all the health issues listed can appear, and have been documented as appearing, in both Standard and Toy Manchester Terriers.
Just as certain breeding lines within a breed may have predispositions toward specific traits, they can also be more susceptible to particular genetic mutations. In the United States, the development of the Toy and Standard varieties has followed a path similar to two distinct breeding lines within the same breed. The health test recommendations are designed to guide breeders in making informed decisions about which tests to prioritize.
4. What health tests should I perform if I’m breeding a Standard Manchester from Toy Manchester parents? What about a dog from a Standard to Toy breeding?
This is a decision best made based on pedigree research of the individual dogs. Ultimately, all tests listed in the OFA CHIC database are recommendations to guide breeders in making informed decisions.
5. What is the cause of congenital deafness?
Congenital means present from birth. It is not something a dog develops over time, but rather something it is born with. In dogs, congenital deafness is most commonly linked to genetics, though the specific genes involved vary by breed. BAER testing is the only acceptable diagnostic tool for detecting it and OFA’s BAER testing program exists specifically to identify and track congenital deafness in dogs.
6. Why do we currently believe this is congenital, hereditary deafness?
The pattern we are seeing strongly points to a genetic and congenital cause for two reasons. First, the leading cause of deafness in dogs is congenital hereditary sensorineural deafness, with acquired (non-hereditary) forms appearing only on rare occasions. The sheer number of affected dogs, across multiple lines and breeding programs is not consistent with acquired deafness from causes like infection, injury or aging.
Second, several affected dogs are unilaterally deaf (deaf in one ear only). Current research notes that unilateral hearing loss rarely results from acquired disease or injury. A dog that tests unilaterally deaf has almost certainly been deaf in that ear since birth.
Therefore, the presence of unilaterally deaf dogs in our affected population is itself strong evidence that we are dealing with congenital deafness.
For further reading, we encourage you to refer to the following article written by leading authority on canine deafness, Dr. George Strain of Louisiana State University’s School of Veterinary Medicine: https://www.lsu.edu/vetmed/deafness/vetclinna.php
7. How can acquired causes of deafness be ruled out?
According to OFA further specialized testing can rule out acquired deafness in a dog that fails a BAER exam, “Under appropriate circumstances, when an ear tests as deaf using air-conducted stimuli, and the possibility of conduction deafness exists (chronic otitis, excess ear wax accumulation), repeat testing with a bone stimulation transducer is recommended.”
8. Where can I get my dogs BAER tested?
BAER Test Sites | Deafness in Dogs & Cats https://lsu.edu/vetmed/deafness/baersite.php
OFA Health Clinics – OFA https://ofa.org/health-clinics/
Dog/Canine Health Test Clinic Schedule https://cavalierhealth.org/health_clinics.htm