How to Avoid Bad Breeding Pairings

Every poor breeding decision has downstream consequences — unhealthy puppies, buyer complaints, reputational damage, and in some cases, significant veterinary costs passed on to families who trusted you. The good news is that most bad pairings are entirely avoidable with the right information.

The Most Common Bad Pairings — and How to Avoid Them

1. Merle × Merle (Double Merle)

This is the highest-profile avoidable error in breeding.

What happens: When two merle dogs are bred, 25% of puppies inherit two copies of the merle gene — a "double merle." These puppies face elevated risk of:

How to avoid it: DNA test both dogs. Any dog confirmed as Mm (merle) should only be bred to a confirmed mm (non-merle) dog. Never assume based on appearance — cryptic merle dogs look non-merle but still carry the gene.

2. Carrier × Carrier for the Same Disease

What happens: Each puppy has a 25% chance of inheriting two copies and being "At Risk" — potentially showing symptoms of the condition.

Common examples:

How to avoid it: Test both dogs. If both carry the same variant, either choose a different pairing or accept that some puppies may be At Risk and plan accordingly.

3. Poor Structure × Poor Structure

What happens: Structural faults compound. Two dogs with steep shoulders produce puppies with steep shoulders. Two dogs with loose hips produce puppies with hip problems.

How to avoid it: Evaluate both dogs' structure before committing to a pairing. Ideally, the stud complements the dam's weaknesses — if she is slightly steep in the shoulder, select a stud with correct angulation.

4. Ignoring Hidden Color Genetics

What happens: You produce colors you did not intend — or fail to produce the colors you did intend. A merle carrier paired incorrectly produces double merle pups. Two solid dogs produce parti puppies that buyers were not expecting.

How to avoid it: Test both dogs at all relevant color loci. Predict the litter's range of possible colors before breeding.

5. Unknown Health Status

What happens: You produce puppies with hereditary conditions that could have been screened for. Buyers face unexpected veterinary costs and heartbreak. Your reputation suffers.

How to avoid it: Full genetic panels on both dogs before breeding. There is no shortcut here.

A Pre-Breeding Checklist

Before finalizing any pairing, confirm:

The Bottom Line

Most bad pairings are not the result of bad intentions — they are the result of missing information. Testing both dogs eliminates the majority of preventable problems before a single puppy is born.