Breeding Collies

Complete Guide for Responsible Breeders

Breeding Collies requires navigating a complex genetic landscape dominated by three critical health concerns: Collie Eye Anomaly (CEA), MDR1 multi-drug sensitivity, and Dermatomyositis (DMS). Unlike many herding breeds where health issues are rare or polygenic, virtually every Collie carries genetic risk for at least one of these conditions, making comprehensive DNA testing and strategic breeding decisions non-negotiable. This guide provides the data, testing protocols, and selection strategies necessary to produce healthy, sound Collies while preserving the breed's signature expression, temperament, and working ability.

Breed Overview

The Collie originated in the highlands of Scotland, where the breed was developed as a sheepdog for both herding and guarding flocks. The name is thought to derive from the Anglo-Saxon word "Col," meaning black. While Collies served as practical farm dogs for centuries, the breed gained widespread popularity in the 20th century through literature and media, particularly Albert Payson Terhune's books and the iconic "Lassie" television series and films, which introduced the breed to a global audience.

The Collie was among the first breeds recognized by the American Kennel Club in 1885, making it one of the foundation breeds of the AKC. Today, the breed is classified in the Herding Group and currently ranks 38th in AKC popularity with stable registration trends. The Collie Club of America serves as the AKC parent club and provides extensive resources for breeders, including genetic testing guidance, breeder referrals, and educational materials.

Unlike the closely related Shetland Sheepdog, which shares similar coloration and head type but in a much smaller package, Collies are medium-to-large herding dogs standing 22-26 inches at the shoulder. The breed's signature sweet expression, flowing coat, and loyal temperament continue to attract fanciers worldwide, though responsible breeders must prioritize health testing to address the breed's well-documented genetic challenges.

Breed Standard Summary for Breeders

The AKC breed standard describes the Collie as "a lithe, strong, responsive, active dog, carrying no useless timber, standing naturally straight and firm." True balance is the hallmark of breed type, with each part in harmonious proportion to every other part and to the whole. When evaluating breeding stock, focus on these structural and temperamental priorities rather than attempting to reproduce the full standard point by point.

Expression and Head Type: The Collie head is arguably the breed's most defining feature. Breeders must select for the smooth, well-blended wedge shape with proper stop and muzzle length in a 1:1 ratio from stop to occiput and stop to nose. The sweet, intelligent, alert, questioning expression depends on correct eye shape (almond, obliquely set), eye color (dark except in blue merles, where one or both blue eyes are permitted), and proper ear set (three-quarters erect with tips breaking forward). Round eyes, light eyes in sables and tris, or prick/hound ears all destroy the correct expression and should be selected against.

Size and Proportion: Males should measure 24-26 inches at the shoulder and weigh 60-75 pounds; females 22-24 inches and 50-65 pounds. Oversized or coarse Collies lose the breed's characteristic elegance, while undersized dogs lack the substance needed for a working heritage. The body should be slightly longer than tall, with length primarily from well-laid-back shoulders and proper rear angulation rather than excessive back length.

Structure and Movement: Collies must possess balanced angulation front and rear to produce the effortless, ground-covering gait called for in the standard. Well-laid-back shoulders (approximately 45 degrees), correct croup angle, and proper rear angulation with well-bent stifles are essential. Straight shoulders and straight rears limit reach and drive, producing a choppy, inefficient gait. When viewing breeding stock in motion, look for smooth, flowing movement with good reach in front and powerful drive from behind, all accomplished without apparent effort.

Coat Quality: The breed standard calls for an abundant double coat with a harsh-textured outer coat and soft, dense undercoat. Short or plush single coats are serious faults. Rough Collies (the more common variety) have profuse coat, while Smooth Collies have a short, dense coat. Both varieties are equally correct and can be interbred, though coat type is genetically determined and breeding smooth to smooth will never produce roughs.

Temperament: Friendly, loyal, trainable temperament is paramount. The standard specifically faults excessive shyness or aggression. Collies should be alert and interested but never nervous, reactive, or fearful. Temperament is highly heritable, and breeding nervous or shy dogs perpetuates these undesirable traits.

Disqualifications: Double merle (homozygous merle) coloring is the only listed disqualification due to associated health concerns including deafness, blindness, and microphthalmia. Never breed merle to merle.

Reproductive Profile

Collies typically produce moderate-sized litters averaging 5 puppies, with a typical range of 4-8 puppies. This is slightly smaller than the litter sizes seen in larger herding breeds like the German Shepherd Dog or Belgian Malinois, but comparable to other medium-sized herding breeds. Very small litters (1-3 puppies) and unusually large litters (9+ puppies) do occur but are less common.

The Collie has a relatively low C-section rate of approximately 15%, significantly lower than brachycephalic breeds and many toy breeds. Most Collies whelp naturally without complications. C-sections are most commonly needed in cases of dystocia in first-time or smaller dams, singleton puppies (which may grow too large), or occasional malpresentations. Older dams (5+ years) may experience variable litter sizes and occasionally lower fertility rates.

Natural breeding is preferred and most common, but artificial insemination is widely used for geographic distance or when natural breeding is impractical. Fresh and chilled AI are commonly used with good success rates. Frozen AI is available but may require veterinary assistance and careful timing using progesterone testing, as frozen semen has a shorter viability window once thawed.

Proper timing is critical for Collie breeding success. Progesterone testing is strongly recommended to pinpoint ovulation and determine optimal breeding dates, particularly for AI breedings or when working with valuable stud dogs. Many breeders report improved conception rates and larger litters when breeding is precisely timed versus relying on behavioral signs alone.

Breeding Age and Timeline

Female Collies typically experience their first heat cycle between 6-8 months of age, though some individuals may not cycle until 10-12 months. Regardless of when the first heat occurs, wait until the second or third heat (18-24 months) before breeding. This allows the female to achieve physical maturity, complete structural development, and reach the minimum age for OFA hip evaluations and thyroid testing.

Males can physically breed as early as 12 months, but most responsible breeders wait until 18-24 months when the male has matured mentally, proven his temperament, and completed all required health testing. Young males may lack experience and confidence, leading to unsuccessful breeding attempts.

Critical Testing Timeline:

24 months (2 years): OFA minimum age for hip dysplasia evaluation. Do not breed Collies before 24 months unless ALL required DNA tests are complete and you plan to do final OFA hips exactly at 24 months prior to first breeding.

12 months: Earliest practical age for thyroid panel (OFA), though results are most reliable at 2+ years when autoimmune thyroiditis typically manifests.

Any age: DNA tests (MDR1, PRA-rcd2, DMS, CEA, Grey Collie Syndrome) can be performed at any age, including puppies. Many breeders test entire litters at 6-8 weeks to determine genetic status before placement.

Annual: Eye examinations (CAER/CERF) if performing phenotypic CEA screening instead of DNA testing; cardiac evaluations if indicated by family history.

Breeding Retirement: Most Collie breeders retire females from breeding between 6-8 years of age, with a maximum of 6 litters per female over her reproductive lifetime. Older dams may experience declining fertility, smaller litters, and increased whelping complications. Males can remain fertile much longer but should be evaluated for overall health and vitality before continuing stud service beyond 8-10 years.

Required Health Testing

The Collie has one of the most comprehensive health testing protocols in the dog fancy, driven by the breed's well-documented genetic disease burden. The Canine Health Information Center (CHIC) requires three DNA tests for Collie certification, but responsible breeders routinely perform additional testing to screen for other known hereditary conditions.

CHIC Required Tests (Minimum for Breeding):

MDR1 (Multi-Drug Resistance 1) DNA Test: Screens for a mutation in the ABCB1 gene causing severe sensitivity to ivermectin, loperamide (Imodium), and numerous other common medications. This is a non-negotiable test for every Collie, as 55-70% of the breed carries at least one copy of the mutation. Affected dogs (MDR1 mutant/mutant) can die from standard doses of heartworm preventive or anti-diarrheal medication. One-time test, approximately $75.

PRA-rcd2 (Progressive Retinal Atrophy) DNA Test: Screens for an autosomal recessive form of PRA caused by a mutation in the RD3 gene. Affected puppies show night blindness by 6 weeks of age and progress to complete blindness by 6-8 months. One-time test, approximately $75.

DMS (Dermatomyositis) DNA Test: Screens for genetic risk across three loci (A, B, and C) that contribute to an autoimmune skin and muscle disease. Nearly all purebred Collies carry at least one risk allele, making this the most complex and challenging genetic issue in the breed. The test provides a risk assessment (clear, low, moderate, high) rather than a simple affected/carrier/clear result. One-time test, approximately $150.

Estimated CHIC Testing Cost: $300 (minimum required tests only)

Additional Recommended Tests:

Beyond the CHIC minimum, serious Collie breeders perform these additional evaluations:

Hip Dysplasia (OFA or PennHIP): While Collies have a low hip dysplasia rate (2.8% per OFA data), hip evaluation is recommended to screen breeding stock and maintain low prevalence. OFA requires minimum age of 24 months. Approximately $200.

Thyroid Panel (OFA): Autoimmune thyroiditis is moderately prevalent in Collies, listed among the 12 most affected breeds. OFA thyroid testing screens for T4, Free T4, T3, Free T3, and thyroid autoantibodies (TgAA). Approximately $150.

Eye Examination (CAER/CERF): Annual eye exams screen for Collie Eye Anomaly (CEA) and other ocular conditions. While a DNA test for CEA is available (see below), some breeders prefer annual phenotypic examinations to screen for late-onset conditions. Approximately $75.

Cardiac Evaluation: Auscultation by a veterinary cardiologist screens for congenital and acquired heart disease. Recommended if family history indicates cardiac concerns. Approximately $150.

CEA (Collie Eye Anomaly) DNA Test: This autosomal recessive test identifies genetic status for CEA, which historically affected 80-85% of Collies. Thanks to widespread testing and selective breeding, prevalence has decreased significantly, but the mutation remains common. Knowing genetic status allows breeders to make informed decisions about carrier-to-carrier breedings. One-time test, approximately $75.

Grey Collie Syndrome (Cyclic Neutropenia) DNA Test: Screens for a recessive mutation causing a fatal blood disorder in grey/dilute Collies. The condition is rare but devastating, with affected puppies showing recurrent infections, stunted growth, and shortened lifespan. One-time test, approximately $75.

Total Estimated Testing Cost (Comprehensive): $1,025 per dog

This is one of the highest testing costs across all AKC breeds, reflecting the Collie's significant genetic disease burden. However, these tests are one-time expenses (except annual eye exams and periodic thyroid panels) that provide critical information for breeding decisions.

Hereditary Health Conditions

The Collie faces a challenging genetic landscape with multiple well-documented hereditary conditions, three of which are so prevalent that they define modern Collie breeding strategy. Understanding inheritance modes, prevalence, and available DNA tests is essential for every Collie breeder.

Collie Eye Anomaly (CEA)

Prevalence: Historically 80-85% phenotypic incidence; significantly reduced in recent decades through testing and selective breeding, but the mutation remains widespread.

Inheritance: Autosomal recessive

DNA Test: Yes (highly recommended)

Clinical Signs: CEA is a congenital eye defect affecting retinal development. Severity ranges dramatically from mild choroidal hypoplasia (thinning of tissue beneath the retina) with no vision impact to severe retinal detachment and blindness. Severity is determined by 6-8 weeks of age and does not progress after that point. Mildly affected dogs may live normal lives with no functional vision problems, while severely affected dogs are blind.

Breeding Implications: The CEA DNA test identifies three genotypes: Normal/Normal (clear), Normal/Affected (carrier), and Affected/Affected (affected, will have some degree of CEA). Clear dogs can be bred to any dog without CEA risk. Carriers can be bred to clear dogs, producing 50% clear and 50% carrier offspring with no affected puppies. Carrier-to-carrier breedings produce 25% affected puppies and should be avoided unless both dogs have exceptional qualities that warrant the risk, in which case affected puppies must be placed in pet homes with full disclosure. Never breed affected to affected.

MDR1 Multi-Drug Sensitivity

Prevalence: 55-70% of Collies carry at least one copy of the mutation (either MDR1 mutant/normal or mutant/mutant).

Inheritance: Autosomal recessive with incomplete dominance. Homozygous mutant/mutant dogs are severely affected. Heterozygous mutant/normal dogs may show mild sensitivity depending on drug and dose.

DNA Test: Yes (absolutely required for every Collie)

Clinical Signs: Dogs with the MDR1 mutation lack functional P-glycoprotein pumps that normally protect the brain from toxic levels of certain drugs. Affected dogs exposed to ivermectin, loperamide (Imodium), and other P-glycoprotein substrate drugs can experience severe neurotoxicity including tremors, seizures, coma, and death. Common heartworm preventives, anti-parasitic medications, and over-the-counter anti-diarrheals can be fatal.

Breeding Implications: This is a management issue rather than a breeding exclusion, as the mutation frequency is so high that eliminating all carriers would devastate the gene pool. The MDR1 test identifies three genotypes: Normal/Normal (no sensitivity), Mutant/Normal (mild sensitivity), and Mutant/Mutant (severe sensitivity). ALL three genotypes can be safely bred provided owners and veterinarians are informed of drug sensitivities. Many breeders aim to produce at least 50% Normal/Normal puppies by breeding Normal/Normal to Mutant/Normal or Normal/Normal to Mutant/Mutant. Mutant/Mutant dogs should be bred to Normal/Normal to avoid producing any Mutant/Mutant offspring unless there is a compelling reason to accept that risk. Always disclose MDR1 status to puppy buyers and educate them about safe vs. dangerous medications.

Dermatomyositis (DMS)

Prevalence: Approximately 18% of Collies have some genetic risk; 6% have high-risk genotype; nearly all purebred Collies carry at least one risk allele.

Inheritance: Complex polygenic involving at least three loci (A, B, and C). Autosomal dominant with variable expressivity means that dogs with risk alleles may or may not develop clinical disease.

DNA Test: Yes (highly recommended)

Clinical Signs: DMS is an autoimmune condition affecting skin and muscles. Lesions typically appear on the face, ears, tail tip, and bony prominences. Muscle atrophy and difficulty swallowing can occur in severe cases. Severity ranges from mild cosmetic lesions that resolve with management to debilitating, progressive disease. Clinical signs typically appear between 6 months and 1 year of age, though occasionally as early as 7 weeks.

Breeding Implications: The DMS test reports risk as Clear (no risk alleles), Low, Moderate, or High. Because nearly all Collies carry at least one risk allele, eliminating all at-risk dogs is impractical. Current breeding recommendations prioritize breeding Clear or Low risk dogs, avoiding High x High risk pairings, and being extremely cautious with Moderate x Moderate breedings. Environmental triggers (stress, sun exposure, vaccination reactions) may influence whether genetically at-risk dogs develop clinical disease. DMS is the most frustrating genetic condition in Collies because genetic risk does not perfectly predict clinical outcome, and environmental management plays a significant role.

Progressive Retinal Atrophy (PRA-rcd2)

Prevalence: Overall frequency unknown; mutation identified in the breed.

Inheritance: Autosomal recessive (RD3 gene mutation)

DNA Test: Yes (CHIC required)

Clinical Signs: Affected puppies show night blindness at 6 weeks of age, progressing to complete blindness by 6-8 months due to abnormal development of rods and cones in the retina.

Breeding Implications: Standard recessive breeding strategy: clear to clear produces all clear; clear to carrier produces 50% clear and 50% carrier; carrier to carrier produces 25% affected (blind). Never breed carrier to carrier, and never breed affected dogs. Because a simple DNA test is available and the condition is devastating, there is no excuse for producing PRA-affected puppies.

Grey Collie Syndrome (Cyclic Neutropenia)

Prevalence: Rare; primarily seen in grey/dilute-colored Collies.

Inheritance: Autosomal recessive (AP3B1 gene mutation)

DNA Test: Yes

Clinical Signs: Dilute grey coat color, recurrent infections every 10-14 days, stunted growth, bleeding episodes, shortened lifespan (usually under 3 years). Clinical signs appear at 8-12 weeks.

Breeding Implications: This is a fatal condition with no treatment. The mutation is tightly linked to the dilute grey coat color. Never breed two grey Collies together (guaranteed to produce affected puppies if both are carriers). Test all grey dogs before breeding. Clear and carrier dogs can be bred safely, but affected dogs should never be bred and are rarely candidates for pet placement due to shortened, suffering-filled lives.

Autoimmune Thyroiditis

Prevalence: Moderate; Collies listed among the 12 most affected breeds.

Inheritance: Polygenic with heritable component

DNA Test: No (diagnosed via OFA thyroid panel)

Clinical Signs: Weight gain, lethargy, coat and skin issues, behavioral changes. Treatable with daily thyroid hormone supplementation.

Breeding Implications: Screen breeding stock via OFA thyroid panels at 2+ years of age. Avoid breeding dogs with autoimmune thyroiditis, as the condition is heritable even if exact mode is unknown. Dogs receiving thyroid supplementation can live normal lives but should ideally not be bred.

Hip Dysplasia

Prevalence: Low (2.8% based on OFA data)

Inheritance: Polygenic with environmental factors

DNA Test: No (diagnosed via OFA or PennHIP radiographs)

Clinical Signs: Lameness, difficulty rising, reduced activity, arthritis.

Breeding Implications: OFA evaluate all breeding stock at 24+ months. Breed only dogs with OFA Fair, Good, or Excellent ratings (or PennHIP scores in the acceptable range). Collies have one of the lowest hip dysplasia rates among medium-to-large breeds; maintain this advantage through continued screening.

Bloat (Gastric Dilatation-Volvulus)

Prevalence: Moderate risk; deep-chested breed.

Inheritance: Polygenic with environmental triggers (feeding practices, stress, exercise timing)

DNA Test: No

Clinical Signs: Distended abdomen, restlessness, unproductive retching, shock; life-threatening emergency requiring immediate surgery.

Breeding Implications: No specific breeding protocol, but educate puppy buyers about risk factors (single large meal per day, rapid eating, exercise immediately after eating, family history). Some breeders recommend prophylactic gastropexy at the time of spay/neuter for at-risk dogs.

Color and Coat Genetics

The Collie is recognized in four color varieties: Sable and White, Tricolor (black with white and tan markings), Blue Merle (mottled grey-black with white and tan), and White (predominantly white with sable, tricolor, or blue merle markings). All four colors are equally correct per the breed standard, though sable is the most common and whites are the least common in the show ring.

Accepted Colors:

• Sable and White: Ranges from light gold to deep mahogany sable with white markings (collar, chest, legs, tail tip, blaze). This is genetically ay/ay or ay/at at the A locus.
• Tricolor: Black body with tan points (eyebrows, cheeks, legs) and white markings. Genetically at/at (tan points) with E/E or E/e at extension (allowing black pigment expression).
• Blue Merle: Diluted black (appearing mottled grey-black) with tan points and white markings. Genetically tricolor (at/at) + Mm (one copy of merle). The merle gene randomly dilutes areas of eumelanin (black pigment), creating the mottled pattern.
• White (Color-Headed White): Predominantly white body with colored head (sable, tricolor, or blue merle) and minimal body color. This is caused by extensive white spotting at the S locus (sw/sw or sp/sp), NOT the merle gene. White Collies are NOT "double merles" and do not have merle-associated health issues.

Disqualifying Colors:

• Double Merle (MM): Breeding merle to merle produces approximately 25% homozygous merle (MM) puppies with excessive white, often accompanied by deafness, blindness, and microphthalmia (small or absent eyes). This is an automatic disqualification and an ethical violation. Never breed merle to merle.
• Any solid color without white markings: Collies should always have white markings (Irish spotting pattern). Solid-colored dogs without white are not typical.

Relevant Genetic Loci:

• A locus (agouti): Controls sable vs. tan points. ay (sable) is dominant to at (tan points). Sable Collies can be ay/ay (will produce only sable or merle offspring) or ay/at (can produce sable, tricolor, and merle depending on mate).
• E locus (extension): Controls whether eumelanin (black) is expressed. All Collies are E/E or E/e (allowing normal color expression). The recessive e/e genotype (recessive red) is not found in Collies.
• K locus (dominant black): Not typically present in Collies, allowing agouti patterns to express. Collies are ky/ky.
• M locus (merle): Mm (heterozygous) produces blue merle. MM (homozygous) produces double merle with health issues (disqualified). mm (no merle) produces non-merle colors. Merle affects only eumelanin (black), so blue merle appears as diluted black on tricolor base. Merle does not dilute phaeomelanin (red/sable), so sable merles exist in other breeds but are not described in the Collie standard.
• S locus (spotting): Controls white markings. Collies typically have si/si (Irish spotting) producing white collar, chest, legs, tail tip, and blaze. Extensive white (sw/sw or sp/sp) produces color-headed white Collies.
• D locus (dilution): Associated with Grey Collie Syndrome when homozygous recessive dd in combination with the cyclic neutropenia mutation.

Health-Linked Color Concerns:

Double Merle (MM): As stated, merle-to-merle breedings produce double merle puppies with severe health problems. This is entirely preventable by never breeding merle to merle. Breeding merle to sable or merle to tricolor is safe and produces approximately 50% merle puppies.

Grey Collie Syndrome (Dilute Grey): Grey/dilute-colored Collies with the dd genotype who are also homozygous for the cyclic neutropenia mutation develop fatal Grey Collie Syndrome. DNA testing identifies carriers. Never breed grey to grey without verifying both are clear or only one is a carrier.

Color Breeding Predictions:

• Sable x Sable: All sable (some may carry tricolor recessively and produce tricolors if both parents are ay/at)
• Sable x Tricolor: 100% sable if sable parent is ay/ay; 50% sable / 50% tricolor if sable parent is ay/at
• Tricolor x Tricolor: 100% tricolor
• Blue Merle x Sable: 50% sable, 50% blue merle (if sable is ay/ay); more complex ratios if sable carries at
• Blue Merle x Tricolor: 50% tricolor, 50% blue merle
• Blue Merle x Blue Merle: NEVER BREED. Produces 25% double merle (disqualified, health issues).

Color-headed white Collies are produced by breeding two dogs with the extensive white genes. Breeding white to white can produce all-white puppies, but responsible breeders typically breed white to colored to avoid confusion with double merles.

Selecting Breeding Stock

Collie breeding stock selection requires balancing conformation quality, genetic health testing, temperament, and genetic diversity. Given the breed's extensive genetic disease burden, health testing results should be weighted heavily alongside structural and temperamental evaluation.

Conformation Priorities:

Expression and Head Type: This is the hallmark of breed type. Prioritize dogs with correct wedge-shaped heads, proper stop, 1:1 muzzle-to-skull ratio, almond-shaped dark eyes (except blue in merles), and three-quarter erect ears with forward-breaking tips. The sweet, intelligent expression is created by the combination of these features. Avoid round eyes, light eyes in sables/tris, prick ears, and hound ears.

Front and Rear Angulation: Balanced angulation produces the Collie's effortless gait. Well-laid-back shoulders (approximately 45 degrees), correct croup angle, and proper rear angulation with well-bent stifles are essential. Straight fronts and rears produce choppy, inefficient movement. Evaluate gait in person whenever possible, as photos can be deceiving.

Coat Quality: Abundant double coat with harsh outer coat and soft, dense undercoat. Short or plush single coats are serious faults. Coat should be profuse but not woolly or overly soft. Breeding for excessive coat length can produce dogs with too much coat for practical maintenance.

Size and Proportion: Males 24-26 inches, females 22-24 inches. Oversized Collies (27+ inches in males, 25+ in females) lose elegance and may have structural issues. Undersized dogs lack substance. Body should be slightly longer than tall with balanced proportions.

Temperament: Friendly, loyal, trainable, stable. Never breed nervous, shy, fearful, or aggressive Collies, as temperament is highly heritable. Evaluate temperament in multiple contexts: at home, in public, with strangers, with other dogs, with children. Collies should be alert and interested but not reactive or anxious.

Movement: Smooth, effortless gait with good reach and drive. Look for dogs that cover ground efficiently without wasted motion.

Common Faults to Select Against:

• Short or plush coat lacking proper texture or double coat
• Narrow or coarse head; lack of proper stop; incorrect muzzle-to-skull ratio
• Round or light eyes (in sables and tricolors)
• Straight shoulders and rear angulation
• Excessive shyness, nervousness, or fearfulness
• Overly tall or heavy build; coarse appearance
• Poor gait (choppy, restricted, inefficient)

Temperament Evaluation:

Evaluate puppies and adults for confidence, friendliness, trainability, and stable reactions to novel stimuli. Collie temperament testing should include exposure to strangers, other dogs, children, novel objects, and loud noises. Puppies should be curious and confident, not fearful or overly cautious. Adults should be calm and friendly in public settings.

Avoid breeding overly shy, nervous, or fearful individuals, as these traits are highly heritable and incompatible with the breed standard. Collies are naturally reserved with strangers but should never be nervous or aggressive. Observe interactions with family members, visitors, and other dogs. Temperament is as important as structure in breeding decisions.

Genetic Diversity and COI:

The Collie has an average coefficient of inbreeding (COI) of approximately 25%, which is moderately high. Target breedings with COI under 10% when possible to maintain genetic diversity and reduce the likelihood of inheriting two copies of recessive disease alleles. Use pedigree analysis tools and databases to calculate COI before breeding.

Line-breeding (breeding related dogs to concentrate desirable traits) can be useful in experienced hands but increases COI and should be balanced with occasional outcross breedings to unrelated lines. Very tight line-breeding (parent-offspring, full sibling) should be avoided in Collies given the high frequency of recessive disease alleles.

Stud Selection:

Choose studs that complement the female's strengths and weaknesses. If the female has a slightly narrow head, choose a stud with excellent head type. If the female's coat is adequate but not profuse, choose a stud with abundant coat from a line known for good coat.

Health testing is non-negotiable. Never use a stud dog without complete testing for MDR1, PRA, and DMS at minimum. OFA hips, thyroid, eyes, and CEA status are strongly recommended. Verify test results directly via OFA.org or the testing laboratory rather than relying solely on the owner's representation.

Stud fees for Collies range from $1,000 (pet-quality or unproven males) to $2,500 (titled, health-tested, proven producers from excellent lines). Most stud fees are in the $1,500 range. Some stud owners offer "pick puppy" arrangements in lieu of cash stud fees.

Show vs. Breeding Quality:

Show-quality Collies are breeding-quality Collies. The breed standard describes the ideal Collie, and breeding stock should conform as closely as possible to that ideal. Breeding "pet quality" Collies because they are not competitive in the show ring perpetuates faults and fails to improve the breed.

That said, not every excellent breeding-quality Collie will finish a championship, particularly in highly competitive regions. Prioritize dogs with correct structure, excellent temperament, complete health testing, and breed type over dogs with major championships but health testing gaps or temperament issues.

Whelping and Neonatal Care

Collies generally whelp naturally without complications, with a C-section rate of approximately 15%. This is significantly lower than brachycephalic breeds (80%+ C-section rates) and many toy breeds, but higher than some working and sporting breeds with 5-10% C-section rates.

Natural Whelping: Most Collie dams experience uncomplicated natural whelping. First-stage labor (restlessness, nesting, temperature drop) typically lasts 6-12 hours. Active labor (visible contractions and puppy delivery) should progress steadily, with puppies born 15-60 minutes apart. A pause of up to 2 hours between puppies can be normal if the dam is resting comfortably, but prolonged straining (30+ minutes) without producing a puppy warrants veterinary evaluation.

C-Section Indications: C-sections are most commonly needed in these situations:

• Dystocia in first-time or smaller dams
• Singleton puppies (may grow too large for natural delivery)
• Malpresentations (breech, transverse)
• Prolonged labor without progress (30+ minutes of strong contractions without puppy delivery)
• Maternal exhaustion
• Large litters (7+ puppies) where the dam tires before completing delivery

Monitor whelping closely and have a veterinary emergency plan. Many breeders establish a relationship with a 24-hour emergency clinic before whelping so they know where to go if complications arise.

Birth Weights: Collie puppies are born weighing approximately 12-16 ounces (males) or 10-14 ounces (females). Smaller puppies (under 10 oz) may need supplemental feeding and extra monitoring. Unusually large puppies (18+ oz) may indicate a small litter with oversized individuals.

Daily Weight Gain: Healthy Collie puppies should gain approximately 1-2 ounces per day, though gain rates vary by litter size (smaller litters = larger puppies = faster gain; larger litters = smaller puppies = slower gain). Weigh puppies daily for the first two weeks to ensure all are gaining steadily. Puppies should double their birth weight by 10-14 days.

Fading Puppy Syndrome: Monitor for failure to gain weight, weakness, crying excessively, inability to nurse, or hypothermia. Fading puppies require immediate intervention including warming, supplemental feeding, and veterinary evaluation. Some fading is caused by congenital defects incompatible with life; others may be saved with aggressive support.

Supplemental Feeding: Most Collie dams have adequate milk for their litters, but large litters (7+ puppies) may benefit from supplemental feeding to ensure all puppies get adequate nutrition. Use commercial puppy milk replacer and bottle-feed or tube-feed puppies that are not gaining adequately.

Dewclaw/Tail/Ear Practices: Collies do not have tails docked or ears cropped. Dewclaws are typically left intact (not removed), as they are considered part of the natural Collie anatomy. Both rough and smooth Collies should retain their natural ears (three-quarter prick, not cropped).

Neonatal Environment: Maintain whelping area temperature at 85-90°F for the first week, gradually decreasing to 75-80°F by 4 weeks. Use heating pads, heat lamps, or radiant warmers, ensuring puppies can move away from heat if too warm. Clean, dry bedding changed frequently to prevent bacterial infections.

Puppy Development Milestones

Collie puppies follow a predictable developmental timeline from birth through placement, with key milestones for growth, socialization, and structural evaluation.

Birth to 2 Weeks (Neonatal Period): Puppies are born with eyes and ears closed, fully dependent on dam for warmth and nutrition. Primary activities are nursing and sleeping. Gain 1-2 oz daily. Eyes open at 10-14 days; ear canals open shortly after.

2-4 Weeks (Transitional Period): Puppies begin interacting with littermates, standing and walking unsteadily, and eliminating without stimulation. Teeth begin erupting at 3 weeks. Start introducing solid food (gruel) at 3-4 weeks to begin weaning process.

3-14 Weeks (Critical Socialization Window): This is the most important period for socialization. Puppies should be exposed to a wide variety of people, environments, sounds, surfaces, and experiences in a positive, non-threatening manner. Proper socialization during this window produces confident, well-adjusted adults. Under-socialized puppies may develop fear, anxiety, or aggression.

Socialization activities for Collie puppies include:

• Handling by multiple people of different ages, sizes, and appearances
• Exposure to children (supervised)
• Novel sounds (vacuum, doorbell, thunderstorm recordings)
• Different surfaces (grass, concrete, tile, carpet, gravel)
• Car rides
• Introduction to grooming tools (brush, nail clippers)
• Exposure to other vaccinated, healthy dogs
• Visits from strangers to the home

6-7 Weeks: Weaning complete. Puppies eating solid food independently. This is a common age for temperament testing (such as Volhard Puppy Aptitude Test) to evaluate confidence, reactivity, and trainability.

8 Weeks: Common age for initial structural evaluation and puppy selection. Experienced breeders can identify show prospects vs. pet prospects based on head type, proportions, angulation, coat, and movement. However, puppies change significantly during growth spurts, so 8-week evaluations are preliminary.

8-10 Weeks: Standard go-home age. Puppies have received first round of vaccinations (typically at 6-8 weeks), have been weaned, and are ready for placement. Some breeders prefer to keep show prospects until 10-12 weeks for further evaluation.

10-14 Weeks: Puppies go through a growth spurt that can temporarily disrupt proportions and structure. Evaluate structure again after this growth spurt for more accurate assessment.

16 Weeks (4 months): Fear period. Puppies may suddenly become wary of previously accepted stimuli. Avoid traumatic experiences during this period. Continue positive socialization but do not force interactions that cause fear.

6-8 Months: Final structural evaluation for show potential. Puppies have achieved most of their growth (though will continue filling out through 18 months) and head type, proportions, and movement are evident. Make final decisions about show vs. breeding vs. pet placements.

12-18 Months: Achieve full adult height by 12-15 months. Continue filling out and developing muscle through 18 months. Collie males in particular may take until 18-24 months to fully mature and develop coat profusion.

Socialization Window: The critical socialization period is 3-14 weeks. Continue socialization through 6 months and beyond, but the foundation is laid in that early window. Under-socialized Collies may develop excessive shyness, nervousness, or fear-based reactivity.

Breeding Economics

Breeding Collies responsibly is an expensive endeavor, driven primarily by the breed's extensive health testing requirements. Be prepared for significant upfront costs before ever producing a litter, and understand that most litters produce modest profits at best.

Health Testing (Per Dog): $1,025

This is one of the highest testing costs across all breeds, reflecting the Collie's genetic disease burden. Required and recommended tests include:

• MDR1 DNA test: $75
• PRA-rcd2 DNA test: $75
• DMS DNA test: $150
• Hip dysplasia (OFA): $200
• Thyroid panel: $150
• Eye examination (CAER): $75
• Cardiac evaluation: $150
• CEA DNA test: $75
• Grey Collie Syndrome DNA test: $75

These tests are primarily one-time expenses (except annual eye exams and periodic thyroid re-testing). You must test both the female AND the stud dog (if you own him), doubling this cost. If using an outside stud, verify he has been tested before proceeding.

Stud Fee: $1,500

Average stud fee for a titled, health-tested Collie from quality lines. Fees range from $1,000 to $2,500. Some stud owners offer pick-puppy arrangements instead of cash fees (typically pick of litter = $2,000-2,500 value).

Progesterone Testing: $200

Recommended for proper breeding timing, particularly for AI breedings. Most bitches require 2-4 blood draws every 1-2 days to pinpoint ovulation, at approximately $50-75 per test.

Prenatal Care: $350

Includes wellness exam, potential ultrasound (pregnancy confirmation at 28+ days, $100-200), and any prenatal diagnostics or supplementation.

Whelping Costs:

Natural whelping: $200 (emergency vet exam if needed, supplies)

C-section: $2,500 (emergency surgery, anesthesia, overnight monitoring)

With a 15% C-section rate, budget for the possibility even if planning a natural whelp. Some breeders establish a "whelping fund" of $2,500-3,000 for emergencies.

Puppy Veterinary Costs: $150 per puppy

Includes first round of vaccinations (6-8 weeks), deworming (multiple treatments from 2-8 weeks), veterinary health checks, and health certificates if required for placement. For an average litter of 5 puppies: $750 total.

Food and Supplies: $400

Increased food for dam during pregnancy and lactation, puppy food from weaning through placement (4-6 weeks of feeding 5 puppies), bedding, whelping supplies, heating, cleaning supplies.

Registration Costs: $200

AKC litter registration, individual puppy registrations (some breeders include this cost in puppy price; others charge buyers separately).

Marketing and Miscellaneous: $100-500

Website maintenance, advertising, puppy buyer communications, contract preparation, travel to stud dog if applicable, genetic testing for entire litter if desired.

Total Cost for Natural Whelping (5-puppy litter): ~$4,625

Total Cost for C-Section (5-puppy litter): ~$6,925

Revenue:

Average Puppy Price (Pet Quality): $1,500

Average Puppy Price (Show Quality): $2,500

Most litters include a mix of pet and show prospects. A typical 5-puppy litter might include 1-2 show prospects ($2,500 each) and 3-4 pet puppies ($1,500 each).

Average Litter Revenue (5 puppies, mixed quality): $7,500-9,000

Net Profit/Loss:

Natural whelping: $7,500 revenue - $4,625 costs = $2,875 profit

C-section whelping: $7,500 revenue - $6,925 costs = $575 profit

These figures assume:

• Average litter size (5 puppies)
• All puppies survive and are placed
• No complications requiring additional vet care
• You already own the dam (not factoring in her purchase price, showing costs, or ongoing maintenance)

Is Breeding Collies Profitable?

Responsible Collie breeding is rarely profitable when you factor in all costs, including the purchase price of quality breeding stock, show expenses to prove quality, ongoing training and maintenance, and time investment. Small litters (3-4 puppies), C-sections, or puppy losses can easily turn a small profit into a significant loss.

Most dedicated Collie breeders break even or lose money on individual litters, viewing breeding as a passion and investment in the breed rather than a profit-generating business. The high health testing costs are a necessary investment in producing healthy puppies, but they significantly impact the bottom line.

If your goal is profit, breeding Collies is not the path. If your goal is producing healthy, well-socialized, structurally correct Collies that advance the breed, the economics can work if you price puppies appropriately and minimize unexpected costs.

Breeder Resources

The Collie has a strong network of parent club support, educational resources, and breeder communities to help both new and experienced breeders.

Parent Club: The Collie Club of America (CCA) is the AKC parent club and offers extensive resources including:

• Breeder referral directory
• Code of Ethics for member breeders
• Genetic testing information and guidance
• Annual national specialty show
• Health and genetics committee resources
• Regional club directory

The CCA is an essential resource for any serious Collie breeder. Membership provides access to experienced mentors, educational seminars, and networking with other breeders committed to breed improvement.

Regional Clubs: Collie clubs exist across the United States, offering local shows, fun matches, herding tests, and educational meetings. Contact the CCA for a directory of regional clubs in your area.

AKC Breeder Programs:

AKC Breeder of Merit: Recognizes breeders who demonstrate a commitment to health testing, continuing education, and responsible breeding practices. Requirements include health testing per breed-specific criteria (easy to achieve with the comprehensive Collie testing protocol), AKC registration of all litters, and participation in AKC events.

AKC Bred with H.E.A.R.T. Program: Emphasizes Health, Education, Accountability, Responsibility, and Tradition. Requires health testing, participation in continuing education, compliance with AKC regulations, and adherence to a code of ethics.

Recommended Books:

• The New Collie by Sarah Hodgson: Comprehensive overview of breed history, standard, care, and breeding.
• The Complete Collie by Iris Combe: Classic text covering breed history and development.
• Collie Concept by Helen Lee James: In-depth discussion of breed type, structure, and breeding philosophy.
• Understanding Collie Genetics by various Collie Club authors: Focused on color genetics and hereditary conditions.

Online Communities:

• Collie Health Foundation (colliehealth.org): Research-focused organization funding studies of Collie health issues. Excellent resource for current genetic research, testing protocols, and breeding recommendations.
• Collie Club of America Members Forum: Private forum for CCA members to discuss breeding, genetics, show results, and health concerns.
• Collie Talk Forum: Online community for Collie enthusiasts. Topics include breeding, genetics, health, training, and show results.
• Breed-Specific Facebook Groups: Several active Facebook groups for Collie breeders, including "Collie Breeders Network" and "Rough & Smooth Collie Fanciers." Verify that groups emphasize responsible breeding and health testing before participating.

Mentorship: Finding an experienced Collie breeder mentor is invaluable, particularly for first-time breeders. Mentors can provide guidance on health testing interpretation, pedigree analysis, whelping, puppy evaluation, and navigating the challenges of the breed's genetic landscape. Contact the CCA or local Collie clubs to connect with potential mentors.

Frequently Asked Questions

How many puppies do Collies typically have?

Collies average 5 puppies per litter, with a typical range of 4-8 puppies. Litters smaller than 4 or larger than 8 occur but are less common. First-time mothers may have smaller litters (3-5 puppies), while experienced dams in their prime reproductive years (3-5 years old) tend to produce larger litters. Older dams (6+ years) may experience declining litter sizes. Very small litters (1-2 puppies) can result in oversized puppies that require C-section delivery due to size.

Do Collies need C-sections?

Collies have a relatively low C-section rate of approximately 15%, meaning the majority (85%) whelp naturally without surgical intervention. C-sections are most commonly needed in cases of dystocia in first-time or smaller dams, singleton puppies (which may grow too large), malpresentations, or when the dam experiences prolonged labor without progress. While most breeders can expect natural whelping, it is wise to budget for the possibility of emergency C-section ($2,500) and have a relationship with a 24-hour emergency veterinary clinic before whelping begins.

What health tests are required for breeding Collies?

The Canine Health Information Center (CHIC) requires three DNA tests for Collie certification: MDR1 (Multi-Drug Resistance 1), PRA-rcd2 (Progressive Retinal Atrophy), and DMS (Dermatomyositis). These tests cost approximately $300 total. However, responsible breeders routinely perform additional testing including hip dysplasia evaluation (OFA or PennHIP, $200), thyroid panel ($150), eye examination (CAER, $75), cardiac evaluation ($150), CEA DNA test ($75), and Grey Collie Syndrome DNA test ($75). Comprehensive testing totals approximately $1,025 per dog, making Collies one of the most expensive breeds to health test.

How much does it cost to breed Collies?

Breeding a litter of Collies costs approximately $4,625 for a natural whelping or $6,925 if a C-section is required (based on 5-puppy average litter). Major expenses include health testing ($1,025 per dog), stud fee ($1,500), progesterone testing ($200), prenatal care ($350), whelping costs ($200-2,500), puppy veterinary care ($750 for 5 puppies), food and supplies ($400), and registration ($200). These figures do not include the purchase price of quality breeding stock, show expenses, or ongoing maintenance costs. Collies have some of the highest per-litter costs among herding breeds due to extensive health testing requirements.

At what age can you breed a Collie?

Female Collies should not be bred until their second or third heat cycle, typically 18-24 months of age. This allows the female to achieve physical maturity and reach the minimum age for OFA hip evaluation (24 months). Males can physically breed at 12 months but should ideally wait until 18-24 months to complete all health testing and achieve mental maturity. Never breed Collies before completing required health testing for MDR1, PRA-rcd2, and DMS at minimum. Most breeders retire females from breeding by 6-8 years of age with a maximum of 6 litters over the reproductive lifetime.

How much do Collie puppies cost?

Pet-quality Collie puppies from health-tested parents typically sell for $1,500, while show-quality puppies range from $2,000 to $2,500. Prices vary by region, breeder reputation, and puppy quality. Responsible breeders who perform comprehensive health testing, raise puppies in home environments with early socialization, and provide lifetime breeder support command higher prices than backyard breeders or puppy mills. Be wary of unusually low prices (under $1,000), which may indicate lack of health testing or poor breeding practices. Color-headed white Collies and blue merles may command slightly higher prices due to rarity.

What are the most common health problems in Collies?

Collie Eye Anomaly (CEA) is the most prevalent genetic condition, historically affecting 80-85% of the breed, though widespread DNA testing has reduced incidence. MDR1 multi-drug sensitivity affects 55-70% of Collies (at least one copy of the mutation), causing severe reactions to common medications like ivermectin and loperamide. Dermatomyositis (DMS) affects approximately 18% of Collies with genetic risk and 6% with high-risk genotypes, causing skin and muscle lesions. Progressive Retinal Atrophy (PRA-rcd2) leads to early blindness in affected dogs. All of these conditions have available DNA tests, making them preventable through testing and selective breeding. Additional health concerns include autoimmune thyroiditis, hip dysplasia (low incidence at 2.8%), and bloat/GDV.

Is breeding Collies profitable?

Breeding Collies responsibly is rarely profitable when all costs are considered. An average litter of 5 puppies with natural whelping generates approximately $2,875 profit after expenses ($7,500 revenue minus $4,625 costs), but this does not account for the purchase price of quality breeding stock, show expenses, ongoing maintenance, or time investment. C-section deliveries reduce profit to approximately $575. Smaller litters, puppy losses, or unexpected veterinary expenses can easily result in financial losses. Most dedicated Collie breeders view breeding as a passion and investment in the breed rather than a profit-generating business. The extensive health testing requirements (approximately $1,025 per dog) are necessary for producing healthy puppies but significantly impact profitability.

What is MDR1 and why does it matter for Collie breeding?

MDR1 (Multi-Drug Resistance 1) is a mutation in the ABCB1 gene that causes severe sensitivity to ivermectin, loperamide (Imodium), and numerous other common medications. Dogs with the mutation lack functional P-glycoprotein pumps that normally protect the brain from toxic drug levels, resulting in neurotoxicity (tremors, seizures, coma, death) when exposed to these drugs. Approximately 55-70% of Collies carry at least one copy of the mutation. MDR1 testing is mandatory for every Collie breeding dog because even heterozygous (mutant/normal) dogs may show mild sensitivity. This is a management issue rather than a breeding exclusion—all three genotypes (normal/normal, mutant/normal, mutant/mutant) can be safely bred, but owners and veterinarians must be informed of drug sensitivities to prevent accidental poisoning from common heartworm preventives and other medications.

Can you breed merle Collies together?

No. Breeding merle to merle (blue merle to blue merle) produces approximately 25% double merle (homozygous MM) puppies with excessive white and severe health problems including deafness, blindness, and microphthalmia (small or absent eyes). Double merle is an automatic disqualification and an ethical violation. Always breed merle to non-merle (blue merle to sable or blue merle to tricolor), which produces approximately 50% merle puppies and 50% non-merle puppies, all with normal health. This is one of the most critical rules in Collie breeding and applies to all merle breeds.

What is the difference between CEA and PRA in Collies?

Both are hereditary eye diseases, but they differ significantly. Collie Eye Anomaly (CEA) is a congenital defect present at birth affecting retinal development. Severity ranges from mild choroidal hypoplasia (no vision impact) to severe retinal detachment and blindness. CEA does not progress after 6-8 weeks of age. Progressive Retinal Atrophy (PRA-rcd2) is a degenerative condition where puppies develop normally but then experience progressive vision loss, starting with night blindness at 6 weeks and progressing to complete blindness by 6-8 months. Both are autosomal recessive with available DNA tests. CEA is extremely common (historically 80-85% incidence), while PRA-rcd2 is less common but devastating. Both should be tested and carriers bred only to clear dogs.

How do you manage Dermatomyositis (DMS) in Collie breeding?

Dermatomyositis is the most complex genetic challenge in Collie breeding because it involves at least three loci (A, B, C) with variable expressivity, meaning genetically at-risk dogs may or may not develop clinical disease. The DNA test reports risk levels (Clear, Low, Moderate, High) rather than simple affected/carrier/clear results. Nearly all purebred Collies carry at least one risk allele, making complete elimination impractical. Current recommendations include breeding Clear or Low risk dogs preferentially, avoiding High x High risk pairings, and using caution with Moderate x Moderate breedings. Environmental factors (stress, sun exposure, vaccination reactions) may influence whether at-risk dogs develop clinical signs. Because genetic risk does not perfectly predict clinical outcome, many breeders focus on producing the lowest-risk puppies possible while accepting that some level of DMS risk is unavoidable in purebred Collies.