What are the main health problems in Australian Shepherds?

Australian Shepherds are generally a fairly hardy, athletic breed, but they have several inherited conditions owners should know about, several shared with other collie-type breeds. The most important concerns are: hip and elbow dysplasia (joint malformations leading to arthritis, seen in the breed as in many active dogs); eye conditions, of which the breed is prone to several (including Collie Eye Anomaly, cataracts, progressive retinal atrophy, and colobomas, so eye health is a notable consideration for the breed); the MDR1 (Multidrug Resistance 1) gene mutation, common in collie-type breeds including Australian Shepherds, which makes affected dogs dangerously sensitive to certain common medications (critically important, covered in its own question below); and epilepsy (a seizure disorder the breed can be prone to). There is also an important issue related to coat colour, dogs of the "double merle" pattern (produced by breeding two merle-coated dogs together) are at high risk of serious congenital problems including deafness and blindness or serious eye defects, which is why responsible breeders never breed two merles together, and which is covered below. Other conditions that can occur include hypothyroidism, certain autoimmune conditions, and, as in many breeds, allergies and others. Many of these are conditions responsible breeders screen for. That is a fair list, but many individual Australian Shepherds are healthy and athletic, and much of managing the breed's health is within an owner's control: know about the critically important MDR1 gene and tell your vet, have the eyes monitored given the breed's eye predispositions, keep the dog lean and fit to protect the joints, and provide good routine veterinary care. For an adopted Aussie, ask the rescue what is known about the dog's health, be aware of the MDR1 issue, and start good preventive care.

What is the MDR1 gene and why does it matter for Australian Shepherds?

The MDR1 (Multidrug Resistance 1) gene mutation is one of the single most important things to know about owning an Australian Shepherd or any collie-type breed, because it can be life-saving. The mutation, common in herding and collie-type breeds including Australian Shepherds, affects a protein that normally pumps certain drugs out of the brain. Dogs with the mutation cannot do this properly, so certain common medications, including some anti-parasite drugs (notably high-dose ivermectin and related compounds), some anti-diarrheal drugs (loperamide/Imodium), certain chemotherapy drugs, some sedatives and anesthetic agents, and others, can build up to toxic levels in the brain and cause severe neurological reactions or even death, at doses that are safe for other dogs. The critical takeaways for an Aussie owner: first, a simple, inexpensive DNA test can tell you whether your dog carries the mutation, and testing is well worth it (a significant proportion of Australian Shepherds carry it); second, whether or not you test, tell your veterinarian your dog is an Australian Shepherd (or collie-type) and ask them to treat it as potentially MDR1-affected, avoiding or adjusting the problem drugs, which is standard practice for these breeds; and third, be careful with over-the-counter medications (never give human medications like Imodium without veterinary guidance) and with livestock/large-animal dewormers. Veterinarians who see herding breeds are generally well aware of MDR1, but it is on you to make sure any vet, especially an emergency vet who does not know your dog, knows it is an Australian Shepherd. This single piece of knowledge can prevent a tragedy, and it is one of the most important health facts about the breed, so make it a priority to know your dog's status or have it treated as affected, and to inform every vet who treats it.

What eye conditions affect Australian Shepherds?

Australian Shepherds are prone to several inherited eye conditions, and eye health is one of the more notable considerations for the breed, so routine eye monitoring is worthwhile. The eye conditions the breed can be affected by include: Collie Eye Anomaly (CEA, an inherited developmental condition present from birth, ranging from mild to, rarely, vision-threatening, and largely non-progressive); cataracts (clouding of the lens, which the breed is prone to and which can impair vision, sometimes treatable surgically); progressive retinal atrophy (PRA, a degenerative condition causing gradual vision loss); colobomas and other eye defects (particularly associated with the merle colouring, and especially serious in double-merle dogs, see the merle question); and others. Because the breed is prone to multiple eye conditions, responsible breeders have their breeding dogs' eyes examined by a veterinary ophthalmologist, and for any Australian Shepherd, routine eye monitoring is worthwhile, watch for signs of vision problems (cloudiness, changes in the eyes, bumping into things, hesitancy in dim light, or vision changes), and have any eye concerns assessed by a veterinarian, ideally a veterinary ophthalmologist for anything significant. Many eye conditions are manageable or treatable, especially when caught early (for example, some cataracts can be surgically corrected), and even a dog that loses some vision can often adapt and live well, particularly given the breed's intelligence and other senses. Given the breed's multiple eye predispositions, eye care and monitoring are a real part of caring for an Australian Shepherd, and the possibility of eye conditions (some potentially needing specialist treatment) is part of the pet-insurance argument. For an adopted Aussie, having the eyes checked as part of routine veterinary care is worthwhile.

What is the double-merle problem in Australian Shepherds?

The double-merle issue is an important, breed-specific health consideration for Australian Shepherds (and other merle breeds), and understanding it is worthwhile. Merle is a coat-colour pattern (a mottled or marbled pattern) that is common and prized in Australian Shepherds, and a dog with one copy of the merle gene has the merle coat and is generally healthy. The problem arises when two merle dogs are bred together: statistically, some of the resulting puppies inherit two copies of the merle gene (a "double merle"), and double-merle dogs are at high risk of serious congenital defects, particularly deafness (in one or both ears) and blindness or serious eye defects, as the double dose of the merle gene disrupts the development of the ears and eyes. Double-merle dogs are often predominantly white in colour. For this reason, responsible breeders never breed two merle dogs together, precisely to avoid producing affected double-merle puppies, and the existence of double-merle dogs is generally the result of irresponsible or careless breeding. Why does this matter for an adopter? First, it is a reason to obtain dogs from responsible sources (reputable breeders who do not do merle-to-merle breeding, or rescues) rather than from careless breeders. Second, you may encounter double-merle Australian Shepherds in rescue, dogs that are deaf, blind, or both as a result of this breeding, and while these dogs face challenges, many deaf and/or blind dogs can live happy, full lives with appropriate accommodations and care, and adopting a deaf or blind double-merle Aussie in need can be a wonderful, if more involved, thing to do (such dogs need adopters prepared for their special needs). So the double-merle issue is both a caution (about the breeding that produces affected dogs) and, sometimes, a consideration for adopters who may have the opportunity to give a home to an affected dog. If you are considering a double-merle or a deaf/blind Aussie, understand the accommodations the dog will need and be prepared for them, and a good rescue can advise. For most adopters, the main takeaway is awareness of why the condition exists and the importance of responsible sourcing.

How long do Australian Shepherds live and is pet insurance worth it in Montreal?

Australian Shepherds are a fairly long-lived breed, typically living around 12 to 15 years, reflecting their general hardiness and athletic build, and many active, well-cared-for Aussies stay fit and healthy well into their senior years. Much of keeping one healthy is within your control: know about and manage the critically important MDR1 gene (test or treat as affected, and make sure every vet knows the dog is an Australian Shepherd, this is the single most important health step); have the eyes monitored given the breed's multiple eye predispositions; keep the dog lean and fit (protecting the joints, and easy given the breed's exercise needs); be aware of the possibility of epilepsy and seek veterinary care if seizures occur; provide the substantial exercise and mental stimulation the breed needs (a well-exercised Aussie is healthier and much happier); maintain the coat with regular grooming; and stay on top of routine veterinary care so any conditions are caught early. On pet insurance: it is worth considering for an Australian Shepherd, because although the breed is relatively hardy, it does have potential conditions that can be costly, eye conditions (some may need specialist care or surgery), epilepsy (requiring lifelong medication), joint issues (which can require surgery), and others, and Montreal veterinary care, especially specialist and emergency care, is not cheap. The breed's longevity also means many years over which conditions can arise. As always, take out insurance while the dog is young and healthy, before any condition is diagnosed and excluded as pre-existing, which matters given the breed's predispositions. Compare providers, understand coverage (including whether hereditary and chronic conditions like epilepsy and the breed's eye conditions are well covered) and any limits, and read the fine print. One Aussie-specific note: the MDR1 gene means being extra careful with medications, an MDR1 drug reaction can require expensive emergency treatment, so the breed's drug sensitivity is one more reason to have a financial cushion. If you self-insure instead, keep a solid vet fund in mind, and note that for an adopted adult or senior Australian Shepherd, some conditions may already be present, so understand what a policy will and will not cover.

Australian Shepherd Health Issues: Montreal Guide

The short answer

The Australian Shepherd is generally hardy and long-lived (~12 to 15 years), but knows several inherited conditions. The most critical: the MDR1 gene, common in collie-type breeds, which makes affected dogs dangerously sensitive to certain common medications, tell every vet your dog is an Aussie (life-saving). Also: multiple eye conditions (Collie Eye Anomaly, cataracts, PRA, colobomas), hip and elbow dysplasia, and epilepsy. A breed-specific caution: the double-merle pattern (from breeding two merles) causes deafness/blindness, hence responsible breeders never do it. The levers you control: know the MDR1 gene, monitor the eyes, keep the dog lean and fit, and stay on routine vet care. Insurance is worth considering, insure while young.

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An Australian Shepherd being examined at a Montreal veterinary clinic — Knowing the MDR1 gene, monitoring the eyes, keeping the dog lean and fit, and routine vet care are the Aussie owner's most valuable health habits.

The Australian Shepherd is a fairly hardy, athletic, long-lived breed, its working heritage bred for soundness, but it comes with a handful of inherited conditions, several shared with other collie-type breeds. Two, the MDR1 gene and the double-merle issue, are especially important to understand. Here is the medical picture, condition by condition, starting with the one that matters most.

The MDR1 gene: the most important thing to know

The MDR1 (Multidrug Resistance 1) gene mutation, common in collie-type breeds including Australian Shepherds, makes affected dogs dangerously sensitive to certain common medications, some anti-parasite drugs (notably high-dose ivermectin), some anti-diarrheals (loperamide/Imodium), certain chemotherapy drugs, and some sedatives/anesthetics, which can build to toxic levels in the brain and cause severe reactions or death at doses safe for other dogs. This is one of the most important health facts about the breed.

The takeaways: a simple, inexpensive DNA test tells you whether your dog carries the mutation (well worth it, a significant proportion of Aussies carry it); whether or not you test, tell every vet your dog is an Australian Shepherd and ask them to treat it as potentially MDR1-affected (standard practice); and be careful with over-the-counter and livestock medications. Make sure any vet, especially an emergency vet who doesn't know your dog, knows it's an Aussie. This single piece of knowledge can prevent a tragedy. The Washington State University veterinary lab pioneered the MDR1 test.

Eye conditions

Aussies are prone to several inherited eye conditions, so eye health is a notable consideration: Collie Eye Anomaly (present from birth, largely non-progressive), cataracts (the breed is prone, sometimes surgically treatable), progressive retinal atrophy (PRA) (gradual vision loss), and colobomas and other eye defects (particularly associated with the merle colouring, and especially serious in double-merle dogs). Routine eye monitoring is worthwhile, watch for cloudiness, vision changes, or bumping into things.

Have any eye concerns assessed (ideally by a veterinary ophthalmologist for anything significant). Many eye conditions are manageable or treatable when caught early (some cataracts can be surgically corrected), and even a dog that loses some vision can often adapt and live well, given the breed's intelligence and other senses. Given the breed's multiple eye predispositions, eye care and monitoring are a real part of caring for an Aussie, and the possibility of conditions needing specialist treatment is part of the insurance argument.

The double-merle issue

Merle is a mottled coat pattern common and prized in Aussies; a dog with one copy of the merle gene has the merle coat and is generally healthy. The problem is breeding two merles together: some puppies inherit two copies (a “double merle”) and are at high risk of deafness and blindness or serious eye defects (often predominantly white). Responsible breeders never breed two merles together, so double-merle dogs are generally the result of careless breeding.

Why it matters for adopters: it's a reason to obtain dogs from responsible sources (rescues, or breeders who don't do merle-to-merle breeding). You may also encounter double-merle Aussies in rescue, deaf, blind, or both, and while these dogs face challenges, many deaf and/or blind dogs live happy, full lives with appropriate accommodations, and adopting a deaf or blind double-merle Aussie in need can be a wonderful, if more involved, thing to do (such dogs need adopters prepared for their special needs; a good rescue can advise). For most adopters, the main takeaway is awareness of why the condition exists and the importance of responsible sourcing.

Joints, epilepsy, lifespan, and insurance

Hip and elbow dysplasia occur, keeping the dog lean and fit is the biggest lever (easy given the breed's exercise needs), avoiding high-impact stress in growing puppies. Epilepsy (a seizure disorder) can occur, often well managed with medication, have any seizure evaluated. Also possible: hypothyroidism and some autoimmune conditions. Aussies are long-lived, typically ~12 to 15 years.

Keeping one healthy: know and manage the MDR1 gene (the single most important step), monitor the eyes, keep the dog lean and fit, be aware of epilepsy, provide the substantial exercise and mental stimulation the breed needs, maintain the coat, and stay on routine vet care. On insurance: worth considering, because although relatively hardy, the breed's potential conditions, eye conditions (specialist care/surgery), epilepsy (lifelong medication), and joint issues, can be costly, and Montreal specialist care isn't cheap. An MDR1 drug reaction can also need expensive emergency care, one more reason for a cushion. Take insurance out while the dog is young, before conditions are excluded. For an adopted adult, understand what a policy covers. See our adoption guide.

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A good rescue shares a dog's known health history, and many can advise on MDR1 testing and any special needs. Refreshed regularly across Montreal-area organizations.

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Frequently Asked Questions

What are the main health problems?

Generally hardy and long-lived, but with inherited conditions: the MDR1 drug-sensitivity gene (most important), multiple eye conditions (Collie Eye Anomaly, cataracts, PRA, colobomas), hip and elbow dysplasia, epilepsy, and the double-merle risk. Many individual Aussies are healthy and athletic.

What is the MDR1 gene?

A mutation common in collie-type breeds that makes affected dogs dangerously sensitive to certain common medications (ivermectin, loperamide, some chemo drugs and sedatives). A DNA test exists, but whether or not you test, tell every vet your dog is an Aussie, this can be life-saving. One of the most important facts about the breed.

What eye conditions affect them?

Several: Collie Eye Anomaly (present from birth, largely non-progressive), cataracts (sometimes surgically treatable), PRA (gradual vision loss), and colobomas (linked to merle colouring). Routine eye monitoring is worthwhile, watch for cloudiness and vision changes, and see a veterinary ophthalmologist for anything significant.

What is the double-merle problem?

Merle is a coat pattern; one copy is fine, but breeding two merles together produces some “double merle” puppies at high risk of deafness and blindness. Responsible breeders never do merle-to-merle breeding. You may meet deaf/blind double-merle Aussies in rescue, they can live happy lives with accommodations, and adopting one is a wonderful, if more involved, thing to do.

How long do they live?

A long-lived breed, typically 12 to 15 years. Know and manage the MDR1 gene, monitor the eyes, keep the dog lean and fit, be aware of epilepsy, provide the substantial exercise and mental work the breed needs, and stay on routine vet care. Many stay fit into their senior years.

Is pet insurance worth it?

Worth considering, eye conditions (specialist care/surgery), epilepsy (lifelong medication), and joint issues can be costly, and the long lifespan means more years for conditions to arise. An MDR1 drug reaction can need expensive emergency care too. Take insurance out while the dog is young. For an adopted adult, understand what a policy covers.

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Australian Shepherd Health Issues