Myotonia Congenita (Australian Cattle Dog) in Dogs

How do I tell if my puppy has myotonia congenita?

That description — stiffness that improves with movement — is the hallmark of myotonia congenita. Signs often appear when puppies start walking. Affected dogs have a stiff, uncoordinated gait sometimes described as 'wooden' or 'bunny-hopping,' and muscles may visibly bulge or appear overdeveloped. The stiffness is most noticeable after rest and typically improves with activity. It's caused by a mutation in the CLCN1 gene affecting chloride channels in muscles. It's seen in Australian Cattle Dogs and Border Collies. A DNA test for CLCN1 confirms the diagnosis. Our vets can help you get a proper workup started.

What should I do if my dog has myotonia congenita?

While there's no cure, supportive care makes a real difference. Regular, gentle exercise helps reduce stiffness — short, frequent walks are better than occasional long ones. Avoid letting your dog get cold, as cold exacerbates muscle stiffness. Warm-up periods before activity help. Some vets prescribe muscle relaxants (like mexiletine) for more severely affected dogs. Keep your dog at a healthy weight to reduce strain on stiff muscles. Avoid situations that require sudden movement. Most dogs with myotonia congenita adapt well and live happy lives. Our vets can discuss whether medication would help your dog's specific case.

Can myotonia congenita in dogs be cured?

Myotonia congenita is a lifelong condition — the chloride channel defect in muscles is genetic and permanent. There's no cure, but symptoms can be managed. The stiffness tends to be most pronounced in young dogs and may stabilize or even slightly improve with age and regular exercise. Medication can help in moderate to severe cases. Most affected dogs lead comfortable lives with good management. The condition isn't typically painful — it's more about mobility and awkwardness than suffering.

How much does managing myotonia congenita cost?

Costs are relatively modest. Initial diagnostics (DNA test, neurological/muscle evaluation) run $200–$800. If medication is prescribed (mexiletine or similar), expect $30–$80/month. Regular vet monitoring every 6–12 months at $100–$200/visit. The biggest ongoing cost may be physical therapy or hydrotherapy if recommended ($50–$80/session). Most dogs don't need intensive medical management. Total annual cost for a typical case is $500–$1,500. Pet insurance coverage for genetic conditions varies. Our vets can help you determine what level of management your dog needs.

How is myotonia congenita inherited in dogs?

Myotonia congenita is autosomal recessive, caused by a CLCN1 gene mutation. It affects Australian Cattle Dogs and Border Collies. Affected dogs have two copies, carriers have one (clinically normal), clear dogs have none. DNA testing is definitive. Never breed two carriers — Carrier × Clear pairings produce no affected puppies. Test all breeding stock and share results with breed clubs. Transparency with puppy buyers about parent testing status is important. Our vets can help interpret results and plan safe pairings.