Crossbreed - no registry group (parent groups: Working + Sporting) · Giant (88-155 lbs typical) · 9-11 years
Mastador
Typically courageous from the Mastiff side and friendly from the Labrador Retriever - but a cross is an individual first: littermates can land at opposite ends of both parents. Meet the dog, not the label.
Crossbreed
88–155 lb
At a glance
Kid-friendly
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First-time owners
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Energy
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Shedding
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Good with cats
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Alone time
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Apartment OK
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Trainability
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What this is
A cross of: Mastiff (English Mastiff) × Labrador Retriever. A cross can inherit from either parent line — in temperament, coat and health. Read both parent breeds, and treat anything shared by both as the risk that matters most.
What this is
What they’re great at
✓ Handles alone time better than most breeds
✓ Devoted family loyalty - nothing gets past them
✓ A natural with children - famously patient
✓ Quick study - learns in a handful of reps
Why it matters
Honest challenges
Prey drive is hardwired
Small fast animals flip an ancient switch - this is wiring, not disobedience.
What helps: ['Management IS the training: never unsupervised with small pets, period', 'Secure fencing plus leash or long line outdoors for life', 'Feed the drive legally: flirt pole and lure-chase games']
Small fast animals flip an ancient switch - this is wiring, not disobedience.
What helps: ['Management IS the training: never unsupervised with small pets, period', 'Secure fencing plus leash or long line outdoors for life', 'Feed the drive legally: flirt pole and lure-chase games']
Selective about dog friends
Not every dog wants a hundred friends - this breed prefers a curated list.
What helps: ['Quality over quantity: a few calm, known companions beat any dog park', 'Parallel walks are the gold-standard introduction', 'Advocate for their space - declining strange dogs is good ownership']
Not every dog wants a hundred friends - this breed prefers a curated list.
What helps: ['Quality over quantity: a few calm, known companions beat any dog park', 'Parallel walks are the gold-standard introduction', 'Advocate for their space - declining strange dogs is good ownership']
Wariness of strangers is the factory setting
Centuries of guarding don't switch off for dinner parties.
What helps: ['Massive early neutrality socialization: calm around strangers, not friends with all', 'Door protocol: place command and managed greetings - no self-employment as bouncer', "Never encourage 'protection' - confidence comes from training, not suspicion"]
Centuries of guarding don't switch off for dinner parties.
What helps: ['Massive early neutrality socialization: calm around strangers, not friends with all', 'Door protocol: place command and managed greetings - no self-employment as bouncer', "Never encourage 'protection' - confidence comes from training, not suspicion"]
Not a starter dog
The combination of drive, power, or independence punishes improvisation.
What helps: ['A rewards-based professional from week one is the cheat code', "Find a breed mentor: the parent club and this breed's Pack", 'Structure and routine do half the training for you']
The combination of drive, power, or independence punishes improvisation.
What helps: ['A rewards-based professional from week one is the cheat code', "Find a breed mentor: the parent club and this breed's Pack", 'Structure and routine do half the training for you']
What you can do
Exercise & training
Exercise: Moderate - daily walks; avoid puppy overexertion (from Mastiff (English Mastiff)) / High - 1-2 hrs/day of vigorous activity plus swimming/fetch (from Labrador Retriever) - a cross can land at either end, or between.
Training profile — Guardian / mastiff / livestock guardian type: Bred to make independent decisions about threats. Your job is teaching them that YOU handle threat assessment. A professional trainer relationship from puppyhood is money well spent.
Sports and outlets that suit them: Leisurely walks · CGC
What you can do
Grooming & coat
Grooming: Low effort expected. The specifics depend entirely on which coat this individual inherited - see coat_and_grooming for the honest version, including matting risk and professional grooming budget.
Shedding: Heavy as a starting expectation - but shedding is one of the least predictable traits in a cross. See coat_and_grooming: a single litter can produce both a low-shed and a full-shedding coat, and no breeder can promise which you'll get.
Good to know
Health to know about
From the Mastiff (English Mastiff) line: Hip/elbow dysplasia, bloat, osteosarcoma, cardiac disease, cystinuria, short lifespan | From the Labrador Retriever line: Hip/elbow dysplasia, obesity, exercise-induced collapse (EIC), PRA, ear infections | SHARED BY BOTH LINES (not diluted by crossing): hip/elbow dysplasia
BOTH parent lines carry risk for: elbow dysplasia. This is the important one to understand - crossing does NOT dilute a risk that both lines share, and 'hybrid vigor' does not apply here. Ask for testing on BOTH sides for these.
Breed-typical tendencies, not a diagnosis. Individual dogs vary enormously — your veterinarian screens for what matters for your dog.
Why it matters
Emergency red flags
Poisoning (chocolate, xylitol, grapes, medications, rodenticide)
Vomiting, drooling, tremors, collapse, or known ingestion
→ Call ASPCA Poison Control 888-426-4435 or Pet Poison Helpline 855-764-7661 immediately; do NOT induce vomiting unless instructed
Vomiting, drooling, tremors, collapse, or known ingestion
→ Call ASPCA Poison Control 888-426-4435 or Pet Poison Helpline 855-764-7661 immediately; do NOT induce vomiting unless instructed
Know your ER
→ Save your nearest 24-hour emergency vet's address and phone in your phone TODAY, not during a crisis
→ Save your nearest 24-hour emergency vet's address and phone in your phone TODAY, not during a crisis
BLOAT / GDV - the minutes-matter emergency for this breed
Unproductive retching (trying to vomit, nothing comes), rapidly swelling/hard belly, drooling, pacing, sudden distress after eating
→ Drive to the ER immediately. Do not wait to see if it passes. Untreated GDV is fatal within hours
Unproductive retching (trying to vomit, nothing comes), rapidly swelling/hard belly, drooling, pacing, sudden distress after eating
→ Drive to the ER immediately. Do not wait to see if it passes. Untreated GDV is fatal within hours
Urinary blockage
Straining with little or no urine produced, crying in the litter posture, vomiting, hard painful belly
→ This is a life-threatening emergency, especially in males - ER immediately
Straining with little or no urine produced, crying in the litter posture, vomiting, hard painful belly
→ This is a life-threatening emergency, especially in males - ER immediately
This page never carries product links in the emergency section. ASPCA Poison Control (888) 426-4435 · Pet Poison Helpline (855) 764-7661.
Good to know
The numbers
Typical ranges for planning, not promises — costs vary by region, breeder and individual dog.
| Group | Crossbreed - no registry group (parent groups: Working + Sporting) |
| Size | Giant (88-155 lbs typical) |
| Lifespan | 9-11 years |
| Healthy adult weight | 88–155 lb |
| Original purpose | Bred as a companion cross, not for a working role. The instincts still arrive from both sides - Mastiff (English Mastiff): Estate guardian and war dog. | Labrador Retriever: Retrieving waterfowl and game for hunters; retrieving fishing nets. |
| Monthly care | $100-$300 (estimated range across both parent lines) |
| Typical puppy price | $800-$3,500 (spans both parent breeds; reputable cross breeders should still health-test BOTH lines) |
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