Australian Shepherd Health Guide: What Every Owner Needs to Know

Breed Overview

Despite their name, Australian Shepherds were developed primarily in the western United States as versatile ranch dogs. They stand 18-23 inches at the shoulder and weigh 40-65 pounds. Aussies come in four recognized colors: black, blue merle, red, and red merle, often with white and copper markings. Their medium-length double coat is weather-resistant and moderately high-maintenance. Some Aussies are born with naturally bobbed tails, while others have full-length tails.

Aussies are extraordinarily intelligent, consistently ranking among the top 10 smartest dog breeds. They have an intense work drive and need a "job" to be happy, whether that is herding livestock, competing in agility, or learning complex tricks. Without adequate mental and physical stimulation, Aussies develop destructive behaviors, excessive barking, and anxiety. They are loyal and affectionate with their families but can be reserved with strangers, making early socialization critical.

Top Health Concerns for Australian Shepherds

1. MDR1 Gene Mutation (Multi-Drug Resistance 1) — Prevalence: ~50%

The MDR1 gene mutation is the single most important health concern for Australian Shepherd owners. Approximately 50% of Aussies carry at least one copy of this mutation, and about 25% are homozygous (two copies), making them highly sensitive to a range of common medications. The MDR1 gene encodes P-glycoprotein, a protein that acts as a gatekeeper in the blood-brain barrier, pumping certain drugs out of the brain. Dogs with the mutation have a defective blood-brain barrier for these substances.

Ivermectin is the most well-known dangerous drug for MDR1-affected dogs. At standard anti-parasitic doses, ivermectin can cause severe neurological toxicity including tremors, blindness, seizures, coma, and death in MDR1-mutant dogs. However, ivermectin is only one of many affected medications. Other dangerous drugs include loperamide (Imodium), acepromazine, butorphanol, certain chemotherapy drugs (vincristine, doxorubicin), and even some commonly used anesthetics and sedatives.

Every Australian Shepherd should be DNA-tested for the MDR1 mutation before receiving any medications. This is a simple cheek swab test that needs to be done only once in the dog's lifetime. Results should be recorded in the dog's medical file, and owners should inform every veterinarian, emergency clinic, and pet sitter about the dog's MDR1 status. For mutant/mutant dogs, safe alternative medications exist for nearly every clinical need. For mutant/normal (carrier) dogs, dose adjustments may be sufficient. This test is non-negotiable and could save your dog's life.

2. Hip and Elbow Dysplasia — Prevalence: Hip ~8%, Elbow ~5%

Both hip and elbow dysplasia affect Australian Shepherds, though at lower rates than many large breeds. Hip dysplasia involves malformation of the hip joint, while elbow dysplasia encompasses several developmental abnormalities of the elbow, including fragmented medial coronoid process, ununited anconeal process, and osteochondritis dissecans. Both conditions are polygenic (influenced by multiple genes) and also affected by environmental factors such as growth rate, nutrition, and exercise during puppyhood.

Signs of hip dysplasia include a swaying gait, reluctance to climb stairs or jump into vehicles, and stiffness after vigorous activity. Elbow dysplasia typically presents as front-leg lameness, often worse after exercise and sometimes shifting between legs. Because Aussies are active dogs that power through discomfort, subtle lameness may be the only early sign. Radiographic screening of breeding stock is essential. Maintaining lean body condition during puppyhood and avoiding excessive jumping or forced running on hard surfaces before growth plates close (around 14-16 months) helps reduce risk.

3. Epilepsy — Prevalence: ~5-10%

Idiopathic epilepsy is one of the most common neurological conditions in Australian Shepherds, with a strong genetic component. Seizures typically begin between 1 and 5 years of age. The breed appears to have a genetic predisposition to both generalized tonic-clonic seizures (grand mal) and focal seizures that may include behaviors such as fly-biting (snapping at invisible flies), staring episodes, or brief periods of altered awareness.

Seizure management in Aussies requires careful attention due to the MDR1 gene mutation. Some anti-epileptic drugs are processed through P-glycoprotein pathways, meaning that MDR1-affected dogs may have altered drug metabolism. Phenobarbital and levetiracetam (Keppra) are commonly used and generally safe regardless of MDR1 status. Potassium bromide is another option. Your veterinarian should be aware of your Aussie's MDR1 status when selecting anticonvulsant medications. Keeping a seizure diary recording date, time, duration, and severity of each episode is invaluable for optimizing treatment.

4. Eye Conditions — Collie Eye Anomaly and Cataracts

Collie Eye Anomaly (CEA) is an inherited developmental defect of the eye that affects Australian Shepherds along with Collies, Border Collies, and Shetland Sheepdogs. CEA involves abnormal development of the choroid (the layer of blood vessels beneath the retina) and can range from mild choroidal hypoplasia (minimal impact on vision) to severe forms with colobomas (holes in the eye structures), retinal detachment, and blindness. The severity of CEA is present at birth and does not progress, though affected puppies may not show obvious clinical signs.

DNA testing for CEA is available and recommended for all Australian Shepherds, particularly breeding stock. A dog needs two copies of the mutation (homozygous) to be clinically affected. Carriers (one copy) are visually normal but can pass the gene to offspring.

Hereditary cataracts are also common in the breed, with posterior subcapsular cataracts being the most frequent type. These typically appear between 2-7 years of age and may progress slowly or remain small and non-visually significant. Annual ophthalmologic examinations by a board-certified veterinary ophthalmologist are recommended throughout the dog's life. Surgical cataract removal is highly successful if vision becomes significantly impaired.

Recommended Health Screenings

The United States Australian Shepherd Association recommends these health evaluations:

• MDR1 DNA test — Cheek swab genetic test (one-time, non-negotiable for every Aussie)
• Hip evaluation — OFA or PennHIP radiographs at 24+ months
• Elbow evaluation — OFA radiographs at 24+ months
• Ophthalmologist evaluation — Annual OFA eye exam by a board-certified veterinary ophthalmologist
• CEA DNA test — Collie Eye Anomaly genetic test (one-time)
• HSF4 DNA test — Hereditary cataracts genetic test (one-time)

Diet and Exercise Guidelines

Australian Shepherds are high-energy athletes that require a nutrient-dense diet to fuel their active lifestyle. Most adult Aussies do well on 1.5-2.5 cups of high-quality food per day, split into two meals, though working and competition dogs may need significantly more. Choose a formula with high-quality animal protein as the first ingredient and adequate fat content (12-18%) for sustained energy. Avoid overfeeding during the rapid growth phase of puppyhood, as excess weight during development increases joint disease risk.

Exercise needs are among the highest of any breed. Australian Shepherds require a minimum of 90 minutes of vigorous activity daily, and many thrive with 2+ hours. Simple walks are insufficient for this breed. They excel at agility, herding trials, flyball, disc dog, rally obedience, and dock diving. Off-leash hiking with reliable recall (which Aussies can learn thanks to their intelligence and desire to work with their handler) is excellent exercise. Mental stimulation is equally critical: puzzle feeders, trick training, and scent work help tire their busy brains.

Without adequate physical and mental exercise, Australian Shepherds develop behavioral problems including destructive chewing, excessive barking, herding of children and other pets (nipping at heels), pacing, and anxiety. A well-exercised Aussie is a calm, content companion; an under-exercised one is a whirlwind of neurotic energy.

When to See the Vet

Beyond routine checkups, see your veterinarian promptly if your Australian Shepherd shows:

• Any adverse reaction after receiving medication (tremors, disorientation, drooling — may indicate MDR1 drug sensitivity)
• Seizure activity of any kind — even brief staring spells or fly-biting behavior
• Lameness or stiffness in any limb, especially after exercise
• Cloudiness or changes in eye appearance
• Difficulty seeing, bumping into objects, or reluctance to navigate in dim light
• Behavioral changes: sudden aggression, confusion, or disorientation
• Unexplained lethargy in a normally high-energy dog

Related Articles