Module: Building Families – Linebreeding, Inbreeding, and Outcrossing

Learning Objectives

After completing this module, you will be able to:

• Explain the differences between linebreeding, inbreeding, and outcrossing.
• Understand how each strategy affects genetic diversity and predictability.
• Recognize when each breeding strategy may be appropriate.
• Interpret the role of Coefficient of Inbreeding (COI) in breeding decisions.
• Balance consistency, health, and preservation when planning matings.
• Develop a long-term breeding philosophy based on family improvement rather than individual dogs.

Introduction

One of the questions every new breeder eventually asks is:

“Should I linebreed, outcross, or avoid related breedings altogether?”

The answer is rarely simple.

Ask ten successful breeders this question and you may receive ten different answers. Some proudly describe themselves as linebreeders. Others believe every generation should introduce new blood. A few dismiss any close relationship between breeding dogs as dangerous. Yet history tells us that nearly every influential kennel in every breed—including the Bedlington Terrier—has used all three breeding strategies at different times.

The real question is not which breeding method is best, but rather when and why should each method be used?

Preservation breeding is not about following rigid rules. It is about understanding genetics well enough to make informed decisions that improve the breed over time. Every breeding strategy has strengths. Every strategy has weaknesses. The art of breeding lies in knowing which tool is appropriate for a particular family of dogs at a particular moment in your breeding program.

This module explores the science behind these breeding strategies while placing them in the context of preservation breeding. Rather than promoting one approach over another, it encourages breeders to think critically about their goals, evaluate the strengths and weaknesses of their bloodlines, and make decisions that serve the long-term health and future of the Bedlington Terrier.

The Goal Is Not to Breed Dogs—It Is to Build Families

One of the greatest shifts in thinking occurs when a breeder stops focusing on producing a single outstanding puppy and begins thinking in terms of families.

Exceptional dogs appear in almost every breeding program. Exceptional families are much rarer.

A family consistently produces:

• Correct breed type
• Stable temperament
• Sound movement
• Good health
• Longevity
• Reproductive soundness
• Predictable quality

That consistency does not happen by accident.

It is created through generations of thoughtful selection.

When experienced breeders evaluate a pedigree, they often pay less attention to the individual champion and more attention to what that champion consistently produced. One extraordinary dog is exciting; a family that repeatedly produces quality is invaluable.

As legendary breeder Lloyd Brackett famously stated:

“Breed the best to the best, and hope for the best.”

Over time, preservation breeders have refined that philosophy to:

“Breed the best family to the best family.”

Families—not individual dogs—are the true units of inheritance.

Why Related Dogs Produce Predictable Puppies

Every puppy receives half of its genetic material from its sire and half from its dam. If those parents share common ancestors, they also share many of the same genes.

The closer the relationship, the more likely offspring will inherit identical copies of those genes.

This increased genetic similarity explains why related dogs often produce puppies that resemble one another.

Unfortunately, genes do not distinguish between virtues and faults.

If related dogs consistently carry:

• Beautiful heads
• Excellent movement
• Wonderful temperaments

those traits become concentrated.

If they also carry:

• Weak fronts
• Poor dentition
• Copper metabolism concerns
• CDDY
• Allergies

those traits become concentrated as well.

Breeding does not create new genetics nearly as often as it reshuffles what already exists.

Understanding Homozygosity

One of the primary goals of selective breeding is increasing homozygosity for desirable traits.

A homozygous dog has inherited the same version of a gene from both parents.

The more homozygous a dog becomes, the more predictably it passes traits to its offspring.

This predictability explains why carefully linebred families often become recognizable over decades.

However, homozygosity is a double-edged sword.

It fixes virtues.

It also fixes faults.

The breeder’s challenge is deciding which traits deserve to become permanent.

Linebreeding: The Preservation Breeder’s Most Valuable Tool

(Expand into approximately 4–5 pages discussing:)

• Historical development
• Why most successful kennels are linebred
• Building recognizable families
• Examples using Bedlington pedigrees
• Managing hidden faults
• When to stop linebreeding
• Signs diversity is decreasing

Include:

Breeder’s Insight

Linebreeding should concentrate excellence—not simply relatives.

Inbreeding: Looking Behind the Curtain

Instead of simply describing father–daughter matings, discuss:

Why have respected breeders occasionally used close inbreeding?

Because it answers one question faster than almost anything else:

What genes does this family actually carry?

Inbreeding acts like a spotlight.

It exposes both strengths and weaknesses.

Historically, livestock breeders used inbreeding to identify hidden recessives before DNA testing existed.

Today, most preservation breeders accomplish this through DNA testing, health records, and family analysis rather than close inbreeding.

Outcrossing: Bringing Fresh Air Into the Gene Pool

Many novice breeders assume an outcross automatically improves health.

That is a myth.

Poor quality crossed with poor quality remains poor quality.

Instead discuss:

• Complementary pedigrees
• Complementary virtues
• Hybrid vigor within breeds
• Why first-generation outcrosses may look inconsistent
• How successful breeders “breed back” after an outcross

Understanding COI Beyond the Number

Many new breeders obsess over percentages.

Instead teach:

COI is:

✔ A probability

Not:

✔ A prediction

Low COI does not guarantee health.

High COI does not guarantee disease.

COI should be interpreted alongside:

• Health testing
• Family history
• Longevity
• Fertility
• Temperament

The Bedlington Terrier Challenge

Unlike numerically large breeds, Bedlington Terriers have a relatively small worldwide breeding population.

This creates unique challenges.

Every breeding decision affects:

• Future genetic diversity
• Availability of stud dogs
• Preservation of important female families
• Rare bloodlines
• Future health

This is why preservation breeders think several generations ahead.

Case Study

Develop three fictional matings.

Kennel A

Very low COI

Poor family history

Several health issues

Kennel B

Moderate COI

Excellent family history

Known carrier managed responsibly

Kennel C

High COI

Excellent type

Falling fertility

Increasing autoimmune disease

Ask students:

Which mating best preserves the breed?

There is no perfect answer.

Only thoughtful reasoning.

Breeder’s Toolbox

When planning every litter ask:

✓ What family am I strengthening?

✓ What fault am I trying to reduce?

✓ What virtue am I preserving?

✓ What diversity am I losing?

✓ What will these puppies contribute ten years from now?

Final Thoughts

The most successful preservation breeders do not identify themselves as linebreeders, outcrossers, or inbreeders. They identify themselves as students of families. They understand that every pedigree tells a story, every breeding decision writes the next chapter, and every generation offers an opportunity to preserve what is best while improving what can be better.

Linebreeding, inbreeding, and outcrossing are not philosophies—they are tools. Like any tools, their value depends entirely on the knowledge, honesty, and foresight of the person using them. The greatest breeders are remembered not because they followed a particular breeding method, but because they consistently produced generations of healthy, sound, recognizable Bedlington Terriers that remained true to the breed’s history, function, and standard. They understood that preservation breeding is measured not by a single exceptional dog, but by the enduring strength of the families they leave behind.