Key Health Tests

What is Hypertrophic Cardiomyopathy (HCM) in Maine Coons?

• Thickened Heart Walls: The heart muscle walls, especially the left ventricle, thickens, reducing its pumping efficiency.
• Genetic Link: A known mutation (A31P) in the MYBPC3 gene      predisposes Maine Coons, but other causes exist, and not all carriers get sick (incomplete penetrance).
• Serious Risks: Can lead to congestive heart failure, blood clots (thrombi), and sudden cardiac death.

Signs & Symptoms (Often Subtle)

• mEssential for diagnnosis,  ruling out other causes like hyperthyroidism or high blood pressure.
• Many cats show no symptoms until a crisis. 

Diagnosis & Management

•  Echocardiogram (Heart Ultrasound):  Essential for diagnosis, ruling out other causes like hyperthyroidism or high blood pressure.
• Genetic Testing: Detects the A31P mutation but doesn't rule out other HCM types.
• Breeding: Affected cats shouldn't breed; carriers can be bred carefully to clear cats to reduce the mutation's frequency.
• Treatment: No cure; medications manage heart rate, blood pressure, and clot risk (e.g., beta-blockers).

Key Takeaway for Breeders

• Regular screening (echo & genetics) for Maine Coons is vital.
• A negative genetic test doesn't guarantee freedom from HCM; clinical signs must still be monitored.

When you hear people talk about Hip Dysplasia and that radiographs have been taken, most people are referring to dogs. But this problem also applies to cats in general. Hip Dysplasia is a hereditary defect in the socket joint (in the pelvis) which means that it is not as deep as it normally should be. Because of this, the ball does not fit exactly in the socket joint, and the surfaces begin to rub against each other, causing the cartilage to degenerate. Then the joint surface is made up solely of bone (the cartilage having been worn away) leaving a bone-against-bone joint surface which is painful for the cat. The problem is that the body cannot renew the cartilage, and the body tries to repair the damage by increasing bone production which only serves to make the problem worse. Cats in general are very good at not showing pain and can suffer from HD without limping at all. Instead, they may move more carefully or less than cats normally do and may also avoid jumping. Cats with a mild degree of HD may not suffer at all.

In New Zealand, hip x-rays for Maine Coons are a standard screening practice, especially for breeding cats, to detect hip dysplasia (HD). Maine Coons are a large breed genetically predisposed to this condition. 

Purpose of Hip X-Rays

• Screening: Reputable      breeders in NZ routinely x-ray their breeding cats to screen for hip dysplasia and prevent passing the genetic condition to offspring.
• Diagnosis: X-rays are used diagnostically if a cat shows clinical signs of hip issues, such as lameness, stiffness, or an altered gait.
• Assessment: The images help veterinarians assess the severity of any joint abnormality, often using a grading system (e.g., OFA, PawPeds, or Australian Grade equivalent). 

The Procedure in NZ

• Sedation is Recommended: Proper positioning for feline hip x-rays can be      uncomfortable, so light sedation is generally recommended to ensure the cat is still and positioned correctly for accurate results.
• Specialised Vets: It is crucial to use a veterinary clinic experienced in      performing hip x-rays for hip scoring, as poor positioning can lead to      inaccurate grading.
• Cost: The cost for a set of diagnostic x-rays in NZ typically ranges from $400      - $800 NZD. 

Evaluation Grades

The evaluation grades on the scale used are the same ones as for hip radiographing dogs, but due to the fact that the anatomical picture is different for cats the usual "Norberg’s angle" is not used. This means that we do not use the ABCD evaluation scale. Instead, we use "normal", "1", "2" and "3" where each hip will be scored separately:

• HS0 - Normal -(grade 0) - no signs of hip dysplasia and/or degenerative joint      disease and the acetabulum covering at least 50% of the femoral head.
• HS1 - Grade 1 (acceptable hips) – The acetabulum covers slightly less than 50% of the femoral head. There are no deforming changes or degenerative joint disease. This grade is considered within the normal functional range, and cats with this classification are not expected to develop clinical      problems.
• HS2 - Grade 2 (moderate hip dysplasia) - moderate signs of hip dysplasia      and/or signs of deforming degenerative joint disease.
• HS3 - Grade 3 (severe hip dysplasia) - severe signs of hip dysplasia and/or      deforming degenerative joint disease.

Where hip scores are borderline, these cats are always graded at the lower score: i.e. scores were conservative in these cases.

In New Zealand, several companies offer DNA testing for Maine Coons, primarily for screening of heritable diseases, coat colours, and blood types. Reputable NZ breeders routinely use these tests to ensure healthy bloodlines, focusing on conditions common in the breed. 

I personally use Orivet to order a full breed profile testing kit online and collect the sample myself, using a simple cheek swab. Then I sent it off to Orivet to analyse. 

Full Breed Profile

Description:

Discover the essence of your breed with Orivet's Full Breed Profiles (FBPs), offering comprehensive genetic screening tailored to each breed's needs. Our panels select from over 260 scientifically validated tests for disease and trait predispositions, ensuring accuracy for your breed. Each FBP includes a DNA Profile for verifying parentage, providing assurance in breeding decisions. Simplifying genetic testing, Orivet makes breed-specific screening straightforward and affordable, focusing on enhancing breed health.

Feline DNA Profile

Description

Also referred to as a DNA Fingerprint, a DNA Profile is unique for your animal and is used to verify parentage. The feline DNA Profile identifies 101 individual single nucleotide polymorphisms (SNPs). A DNA Profile allows you to verify any mating, an external stud service or any multiple sires. All Full Breed Profile requests include a DNA Profile. DNA profiling is a once off cost and is recommended for any breeding animal.

Important Information

As part of my commitment to being a responsible, reputable breeder, every one of my Maine Coons is registered with the New Zealand Cat Fancy (NZCF).

For more information, go to https://nzcf.com/