UK · 2010
92.3%
Boston Terrier
86.1%
Bulldog
81.3%
French Bulldog
Per-breed C-section proportions for 151 breeds across 22,005 UK Kennel Club litters; the largest published breed-level survey.
J Small Anim Pract 51:113-118
Research by BreedTracker · Data: Evans & Adams 2010 (J Small Anim Pract 51:113-118) · Borge et al. 2011 (Theriogenology 75:911-919) · Schrank et al. 2022 (Front Vet Sci 9:934273)
Peer-reviewed sources · 201 breeds · Updated 2026
C-section rates and mean litter sizes for 144 breeds, drawn from two large peer-reviewed veterinary population studies. Sort, search, and filter by AKC group or brachycephalic status. All values trace to cited sources; breeds without published data are clearly marked.
| Source | ||||
|---|---|---|---|---|
| Boston TerrierBrachy | non-sporting | 4.11 to 8 | 92.3% | Evans 2010 |
| BulldogBrachy | non-sporting | 5.41 to 10 | 86.1% | Evans 2010 |
| French BulldogBrachy | non-sporting | 4.71 to 8 | 81.3% | Evans 2010 |
| MastiffBrachy | working | n/a | 64.6% | Evans 2010 |
| Scottish Terrier | terrier | n/a | 59.8% | Evans 2010 |
| Miniature Bull Terrier | terrier | n/a | 52.4% | Evans 2010 |
| German Wirehaired Pointer | sporting | 7.31 to 14 | 47.8% | Evans 2010 |
| Clumber Spaniel | sporting | n/a | 45.2% | Evans 2010 |
| PekingeseBrachy | toy | n/a | 43.8% | Evans 2010 |
| Dandie Dinmont Terrier | terrier | n/a | 41.4% | Evans 2010 |
| Saint Bernard | working | 6.81 to 18 | 41.2% | Evans 2010 |
| Irish Wolfhound | hound | n/a | 40.3% | Evans 2010 |
| Sealyham Terrier | terrier | n/a | 40.0% | Evans 2010 |
| Brussels GriffonBrachy | toy | n/a | 39.0% | Evans 2010 |
| Greyhound | hound | n/a | 37.8% | Evans 2010 |
| Norwich Terrier | terrier | n/a | 36.6% | Evans 2010 |
| Neapolitan MastiffBrachy | working | n/a | 36.4% | Evans 2010 |
| Pembroke Welsh Corgi | herding | 5.51 to 9 | 35.7% | Evans 2010 |
| BullmastiffBrachy | working | n/a | 35.4% | Evans 2010 |
| Basset Hound | hound | 6.71 to 11 | 35.3% | Evans 2010 |
| Alaskan Malamute | working | 6.92 to 11 | 35.0% | Evans 2010 |
| Chihuahua | toy | 3.21 to 7 | 34.4% | Evans 2010 |
| Dachshund | hound | 5.41 to 13 | 31.2% | Evans 2010 |
| Swedish Vallhund | herding | n/a | 30.0% | Evans 2010 |
| Briard | herding | n/a | 29.8% | Evans 2010 |
| Great Pyrenees | working | n/a | 28.9% | Evans 2010 |
| Spinone Italiano | sporting | n/a | 28.3% | Evans 2010 |
| Chow ChowBrachy | non-sporting | 4.41 to 9 | 28.1% | Evans 2010 |
| Scottish Deerhound | hound | n/a | 28.1% | Evans 2010 |
| Dogue de BordeauxBrachy | working | 8.12 to 17 | 27.8% | Evans 2010 |
| Schipperke | non-sporting | n/a | 27.7% | Evans 2010 |
| PugBrachy | toy | 4.21 to 8 | 27.4% | Evans 2010 |
| Great Dane | working | 7.11 to 13 | 27.1% | Evans 2010 |
| Pointer | sporting | 7.21 to 12 | 26.0% | Evans 2010 |
| Australian Cattle Dog | herding | n/a | 25.7% | Evans 2010 |
| Bernese Mountain Dog | working | 6.41 to 15 | 25.6% | Evans 2010 |
| Siberian Husky | working | 5.11 to 14 | 24.6% | Evans 2010 |
| AffenpinscherBrachy | toy | n/a | 24.4% | Evans 2010 |
| Finnish Spitz | non-sporting | 3.72 to 6 | 24.3% | Evans 2010 |
| Leonberger | working | 8.41 to 15 | 23.6% | Evans 2010 |
| Samoyed | working | 6.21 to 12 | 23.4% | Evans 2010 |
| Bull Terrier | terrier | 5.51 to 9 | 23.1% | Evans 2010 |
| Lakeland Terrier | terrier | n/a | 22.6% | Evans 2010 |
| Parson Russell Terrier | terrier | n/a | 22.4% | Evans 2010 |
| Cesky Terrier | terrier | n/a | 22.2% | Evans 2010 |
| English Setter | sporting | 6.41 to 13 | 22.2% | Evans 2010 |
| Pomeranian | toy | 2.41 to 6 | 22.0% | Evans 2010 |
| Cardigan Welsh Corgi | herding | n/a | 21.9% | Evans 2010 |
| English Toy Spaniel | toy | n/a | 21.8% | Evans 2010 |
| Miniature Schnauzer | terrier | 4.71 to 10 | 21.5% | Evans 2010 |
| Afghan Hound | hound | n/a | 21.3% | Evans 2010 |
| Beagle | hound | 5.51 to 10 | 21.2% | Evans 2010 |
| Maltese | toy | n/a | 21.1% | Evans 2010 |
| Shih TzuBrachy | toy | 4.21 to 9 | 21.1% | Evans 2010 |
| Bouvier des Flandres | herding | n/a | 20.5% | Evans 2010 |
| Labrador Retriever | sporting | 6.91 to 13 | 20.2% | Evans 2010 |
| Polish Lowland Sheepdog | herding | n/a | 20.0% | Evans 2010 |
| Sussex Spaniel | sporting | n/a | 19.4% | Evans 2010 |
| Staffordshire Bull Terrier | terrier | 5.61 to 12 | 19.1% | Evans 2010 |
| West Highland White Terrier | terrier | 3.71 to 8 | 18.9% | Evans 2010 |
| Glen of Imaal Terrier | terrier | n/a | 18.8% | Evans 2010 |
| Standard Schnauzer | working | 7.02 to 11 | 18.8% | Evans 2010 |
| BoxerBrachy | working | 6.61 to 12 | 17.7% | Evans 2010 |
| Golden Retriever | sporting | 7.51 to 14 | 17.7% | Evans 2010 |
| Border Terrier | terrier | 5.11 to 9 | 17.5% | Evans 2010 |
| Brittany | sporting | 6.41 to 10 | 17.5% | Evans 2010 |
| Papillon | toy | 3.31 to 7 | 17.5% | Evans 2010 |
| Airedale Terrier | terrier | n/a | 17.3% | Evans 2010 |
| Norfolk Terrier | terrier | 2.51 to 5 | 17.3% | Evans 2010 |
| Rottweiler | working | 7.41 to 14 | 17.3% | Evans 2010 |
| Puli | herding | n/a | 17.2% | Evans 2010 |
| Cairn Terrier | terrier | 4.41 to 8 | 17.1% | Evans 2010 |
| Finnish Lapphund | herding | 5.22 to 9 | 16.7% | Evans 2010 |
| Old English Sheepdog | herding | n/a | 15.9% | Evans 2010 |
| Dalmatian | non-sporting | 8.41 to 15 | 15.8% | Evans 2010 |
| Manchester Terrier | terrier | 4.72 to 7 | 15.5% | Evans 2010 |
| Tibetan Spaniel | non-sporting | 3.81 to 8 | 15.5% | Evans 2010 |
| Whippet | hound | 6.11 to 10 | 15.1% | Evans 2010 |
| Wire Fox Terrier | terrier | n/a | 15.1% | Evans 20101 source |
| Kerry Blue Terrier | terrier | n/a | 14.8% | Evans 2010 |
| Saluki | hound | n/a | 14.8% | Evans 2010 |
| Basenji | hound | 4.81 to 8 | 14.7% | Evans 2010 |
| Japanese ChinBrachy | toy | n/a | 14.5% | Evans 2010 |
| Newfoundland | working | 6.51 to 12 | 14.5% | Evans 2010 |
| Shetland Sheepdog | herding | 3.91 to 8 | 14.5% | Evans 2010 |
| Borzoi | hound | n/a | 13.9% | Evans 2010 |
| Flat-Coated Retriever | sporting | 8.31 to 15 | 13.6% | Evans 2010 |
| Lhasa ApsoBrachy | non-sporting | 4.91 to 9 | 13.4% | Evans 2010 |
| Cavalier King Charles SpanielBrachy | toy | 4.11 to 15 | 13.1% | Evans 2010 |
| Wirehaired Vizsla | sporting | n/a | 12.5% | Evans 2010 |
| Keeshond | non-sporting | n/a | 12.2% | Evans 2010 |
| Giant Schnauzer | working | 7.01 to 14 | 11.8% | Evans 2010 |
| Vizsla | sporting | n/a | 11.8% | Evans 2010 |
| Toy Poodle | toy | 2.41 to 4 | 11.6% | Evans 20101 source |
| Collie | herding | 5.21 to 10 | 11.1% | Evans 2010 |
| Irish Setter | sporting | 7.11 to 13 | 11.1% | Evans 2010 |
| Poodle (Standard) | non-sporting | 7.02 to 12 | 11.1% | Evans 2010 |
| Chinese Crested | toy | 4.31 to 9 | 10.8% | Evans 2010 |
| Cocker Spaniel | sporting | 5.31 to 10 | 10.8% | Evans 2010 |
| Doberman Pinscher | working | 7.01 to 13 | 10.8% | Evans 2010 |
| Norwegian Elkhound | hound | 5.51 to 12 | 10.7% | Evans 2010 |
| Soft Coated Wheaten Terrier | terrier | 5.81 to 10 | 10.7% | Evans 2010 |
| Border Collie | herding | 6.01 to 16 | 10.6% | Evans 2010 |
| Irish Red and White Setter | sporting | n/a | 10.4% | Evans 2010 |
| English Springer Spaniel | sporting | 7.31 to 13 | 10.3% | Evans 2010 |
| Manchester Terrier (Toy) | toy | n/a | 10.3% | Evans 20101 source |
| Akita | working | n/a | 10.2% | Evans 2010 |
| German Shorthaired Pointer | sporting | 8.31 to 15 | 10.2% | Evans 2010 |
| Tibetan Terrier | non-sporting | 5.21 to 9 | 10.2% | Evans 2010 |
| English Cocker Spaniel | sporting | 5.71 to 14 | 10.1% | Evans 2010 |
| Yorkshire Terrier | toy | 3.51 to 6 | 10.1% | Evans 2010 |
| Italian Greyhound | toy | 3.31 to 6 | 9.9% | Evans 2010 |
| Otterhound | hound | n/a | 9.7% | Evans 2010 |
| Bloodhound | hound | n/a | 9.5% | Evans 2010 |
| Gordon Setter | sporting | 7.61 to 16 | 9.3% | Evans 2010 |
| German Shepherd Dog | herding | 6.11 to 14 | 9.1% | Schrank 20221 source |
| Havanese | toy | 4.31 to 9 | 9.1% | Evans 2010 |
| Field Spaniel | sporting | n/a | 8.3% | Evans 2010 |
| Lagotto Romagnolo | sporting | 6.74 to 12 | 8.3% | Evans 2010 |
| Welsh Springer Spaniel | sporting | n/a | 8.3% | Evans 2010 |
| Löwchen | non-sporting | n/a | 7.4% | Evans 2010 |
| Shiba Inu | non-sporting | 3.31 to 7 | 7.4% | Evans 2010 |
| Bearded Collie | herding | n/a | 7.2% | Evans 2010 |
| Pyrenean Shepherd | herding | n/a | 7.1% | Evans 20101 source |
| Welsh Terrier | terrier | n/a | 7.1% | Evans 2010 |
| Chesapeake Bay Retriever | sporting | n/a | 6.8% | Evans 2010 |
| Rhodesian Ridgeback | hound | 8.91 to 15 | 6.4% | Evans 2010 |
| Canaan Dog | herding | n/a | 6.3% | Evans 2010 |
| Weimaraner | sporting | n/a | 6.3% | Evans 2010 |
| Bedlington Terrier | terrier | n/a | 6.1% | Evans 2010 |
| Bichon Frise | non-sporting | 4.61 to 10 | 5.6% | Evans 2010 |
| Skye Terrier | terrier | n/a | 5.6% | Evans 2010 |
| Irish Water Spaniel | sporting | n/a | 5.5% | Evans 2010 |
| Poodle (Miniature) | non-sporting | 3.01 to 8 | 5.3% | Evans 2010 |
| Miniature Pinscher | toy | 4.31 to 7 | 4.8% | Evans 2010 |
| Australian Terrier | terrier | 5.51 to 8 | 4.5% | Evans 2010 |
| Chinese Shar-Pei | non-sporting | n/a | 2.7% | Evans 2010 |
| Australian Shepherd | herding | n/a | 1.8% | Evans 2010 |
| Curly-Coated Retriever | sporting | n/a | 0.0% | Evans 2010 |
| German Pinscher | working | n/a | 0.0% | Evans 2010 |
| Irish Terrier | terrier | n/a | 0.0% | Evans 2010 |
| Pharaoh Hound | hound | n/a | 0.0% | Evans 20101 source |
| Portuguese Water Dog | working | n/a | 0.0% | Evans 2010 |
| Silky Terrier | toy | n/a | 0.0% | Evans 2010 |
| American English Coonhound | hound | No published data | ||
| American Eskimo Dog | non-sporting | No published data | ||
| American Foxhound | hound | No published data | ||
| American Hairless Terrier | terrier | No published data | ||
| American Staffordshire Terrier | terrier | No published data | ||
| American Water Spaniel | sporting | No published data | ||
| Anatolian Shepherd Dog | working | No published data | ||
| Azawakh | hound | No published data | ||
| Barbet | sporting | No published data | ||
| Beauceron | herding | No published data | ||
| Belgian Laekenois | herding | No published data | ||
| Belgian Malinois | herding | No published data | ||
| Belgian Sheepdog | herding | 6.32 to 11 | n/a | Borge 2011 |
| Belgian Tervuren | herding | 6.21 to 11 | n/a | Borge 2011 |
| Berger Picard | herding | No published data | ||
| Biewer Terrier | toy | No published data | ||
| Black and Tan Coonhound | hound | No published data | ||
| Black Russian Terrier | working | No published data | ||
| Bluetick Coonhound | hound | No published data | ||
| Boerboel | working | No published data | ||
| Boykin Spaniel | sporting | No published data | ||
| Cane CorsoBrachy | working | No published data | ||
| Chinook | working | No published data | ||
| Cirneco dell'Etna | hound | No published data | ||
| Coton de Tulear | non-sporting | 3.81 to 7 | n/a | Borge 2011 |
| Dogo Argentino | working | No published data | ||
| English Foxhound | hound | No published data | ||
| Entlebucher Mountain Dog | herding | No published data | ||
| Grand Basset Griffon Vendéen | hound | No published data | ||
| Greater Swiss Mountain Dog | working | No published data | ||
| Harrier | hound | No published data | ||
| Ibizan Hound | hound | No published data | ||
| Icelandic Sheepdog | herding | 4.52 to 6 | n/a | Borge 2011 |
| Komondor | working | No published data | ||
| Kuvasz | working | No published data | ||
| Miniature American Shepherd | herding | No published data | ||
| Mudi | herding | No published data | ||
| Nederlandse Kooikerhondje | sporting | No published data | ||
| Norwegian Buhund | herding | 4.91 to 8 | n/a | Borge 2011 |
| Norwegian Lundehund | non-sporting | 3.21 to 5 | n/a | Borge 2011 |
| Nova Scotia Duck Tolling Retriever | sporting | 6.62 to 12 | n/a | Borge 2011 |
| Petit Basset Griffon Vendéen | hound | 5.11 to 10 | n/a | Borge 2011 |
| Plott Hound | hound | No published data | ||
| Portuguese Podengo Pequeno | hound | No published data | ||
| Pumi | herding | No published data | ||
| Rat Terrier | terrier | No published data | ||
| Redbone Coonhound | hound | No published data | ||
| Russell Terrier | terrier | 4.41 to 10 | n/a | Borge 2011 |
| Russian Toy | toy | No published data | ||
| Sloughi | hound | No published data | ||
| Smooth Fox Terrier | terrier | No published data | ||
| Spanish Water Dog | herding | No published data | ||
| Tibetan Mastiff | working | No published data | ||
| Toy Fox Terrier | toy | No published data | ||
| Treeing Walker Coonhound | hound | No published data | ||
| Wirehaired Pointing Griffon | sporting | No published data | ||
| Xoloitzcuintli | non-sporting | No published data | ||
201 breeds
Visual analysis
Top 20 breeds by documented C-section rate. Source: Evans and Adams 2010 (UK Kennel Club, 22,005 litters).
| Rank | Breed | C-section rate |
|---|---|---|
| 1 | Boston Terrier | 92.3% |
| 2 | Bulldog | 86.1% |
| 3 | French Bulldog | 81.3% |
| 4 | Mastiff | 64.6% |
| 5 | Scottish Terrier | 59.8% |
| 6 | Miniature Bull Terrier | 52.4% |
| 7 | German Wirehaired Pointer | 47.8% |
| 8 | Clumber Spaniel | 45.2% |
| 9 | Pekingese | 43.8% |
| 10 | Dandie Dinmont Terrier | 41.4% |
| 11 | Saint Bernard | 41.2% |
| 12 | Irish Wolfhound | 40.3% |
| 13 | Sealyham Terrier | 40% |
| 14 | Brussels Griffon | 39% |
| 15 | Greyhound | 37.8% |
| 16 | Norwich Terrier | 36.6% |
| 17 | Neapolitan Mastiff | 36.4% |
| 18 | Pembroke Welsh Corgi | 35.7% |
| 19 | Bullmastiff | 35.4% |
| 20 | Basset Hound | 35.3% |
| Breed | C-section rate (%) | Avg litter size | Brachycephalic |
|---|---|---|---|
| Alaskan Malamute | 35 | 6.9 | No |
| Australian Terrier | 4.5 | 5.5 | No |
| Basenji | 14.7 | 4.8 | No |
| Basset Hound | 35.3 | 6.7 | No |
| Beagle | 21.2 | 5.5 | No |
| Bernese Mountain Dog | 25.6 | 6.4 | No |
| Bichon Frise | 5.6 | 4.6 | No |
| Border Collie | 10.6 | 6 | No |
| Border Terrier | 17.5 | 5.1 | No |
| Boston Terrier | 92.3 | 4.1 | Yes |
| Boxer | 17.7 | 6.6 | Yes |
| Brittany | 17.5 | 6.4 | No |
| Bull Terrier | 23.1 | 5.5 | No |
| Bulldog | 86.1 | 5.4 | Yes |
| Cairn Terrier | 17.1 | 4.4 | No |
| Cavalier King Charles Spaniel | 13.1 | 4.1 | Yes |
| Chihuahua | 34.4 | 3.2 | No |
| Chinese Crested | 10.8 | 4.3 | No |
| Chow Chow | 28.1 | 4.4 | Yes |
| Cocker Spaniel | 10.8 | 5.3 | No |
| Collie | 11.1 | 5.2 | No |
| Dachshund | 31.2 | 5.4 | No |
| Dalmatian | 15.8 | 8.4 | No |
| Doberman Pinscher | 10.8 | 7 | No |
| Dogue de Bordeaux | 27.8 | 8.1 | Yes |
| English Cocker Spaniel | 10.1 | 5.7 | No |
| English Setter | 22.2 | 6.4 | No |
| English Springer Spaniel | 10.3 | 7.3 | No |
| Finnish Lapphund | 16.7 | 5.2 | No |
| Finnish Spitz | 24.3 | 3.7 | No |
| Flat-Coated Retriever | 13.6 | 8.3 | No |
| French Bulldog | 81.3 | 4.7 | Yes |
| German Shepherd Dog | 9.1 | 6.1 | No |
| German Shorthaired Pointer | 10.2 | 8.3 | No |
| German Wirehaired Pointer | 47.8 | 7.3 | No |
| Giant Schnauzer | 11.8 | 7 | No |
| Golden Retriever | 17.7 | 7.5 | No |
| Gordon Setter | 9.3 | 7.6 | No |
| Great Dane | 27.1 | 7.1 | No |
| Havanese | 9.1 | 4.3 | No |
| Irish Setter | 11.1 | 7.1 | No |
| Italian Greyhound | 9.9 | 3.3 | No |
| Labrador Retriever | 20.2 | 6.9 | No |
| Lagotto Romagnolo | 8.3 | 6.7 | No |
| Leonberger | 23.6 | 8.4 | No |
| Lhasa Apso | 13.4 | 4.9 | Yes |
| Manchester Terrier | 15.5 | 4.7 | No |
| Miniature Pinscher | 4.8 | 4.3 | No |
| Miniature Schnauzer | 21.5 | 4.7 | No |
| Newfoundland | 14.5 | 6.5 | No |
| Norfolk Terrier | 17.3 | 2.5 | No |
| Norwegian Elkhound | 10.7 | 5.5 | No |
| Papillon | 17.5 | 3.3 | No |
| Pembroke Welsh Corgi | 35.7 | 5.5 | No |
| Pointer | 26 | 7.2 | No |
| Pomeranian | 22 | 2.4 | No |
| Poodle (Miniature) | 5.3 | 3 | No |
| Poodle (Standard) | 11.1 | 7 | No |
| Toy Poodle | 11.6 | 2.4 | No |
| Pug | 27.4 | 4.2 | Yes |
| Rhodesian Ridgeback | 6.4 | 8.9 | No |
| Rottweiler | 17.3 | 7.4 | No |
| Saint Bernard | 41.2 | 6.8 | No |
| Samoyed | 23.4 | 6.2 | No |
| Shetland Sheepdog | 14.5 | 3.9 | No |
| Shiba Inu | 7.4 | 3.3 | No |
| Shih Tzu | 21.1 | 4.2 | Yes |
| Siberian Husky | 24.6 | 5.1 | No |
| Soft Coated Wheaten Terrier | 10.7 | 5.8 | No |
| Staffordshire Bull Terrier | 19.1 | 5.6 | No |
| Standard Schnauzer | 18.8 | 7 | No |
| Tibetan Spaniel | 15.5 | 3.8 | No |
| Tibetan Terrier | 10.2 | 5.2 | No |
| West Highland White Terrier | 18.9 | 3.7 | No |
| Whippet | 15.1 | 6.1 | No |
| Yorkshire Terrier | 10.1 | 3.5 | No |
C-section rate vs. litter size · 76 breeds with both data points
Brachycephalic breeds
Among the 18 brachycephalic breeds in this dataset, 17 have published C-section data. Their median surgical delivery rate is 28.1% - well above the overall pedigree population rate of 12.7 to 15.5% reported by Secher et al. 2025 across 35,121 Danish litters. Three independent studies in three countries corroborate the pattern.
UK · 2010
92.3%
Boston Terrier
86.1%
Bulldog
81.3%
French Bulldog
Per-breed C-section proportions for 151 breeds across 22,005 UK Kennel Club litters; the largest published breed-level survey.
J Small Anim Pract 51:113-118
A / D / CH · 2022
open access21.6%
Overall C-section rate
899 litters across 80 breeds at a German-speaking referral clinic; corroborates UK findings and provides elective vs emergency breakdown.
Front Vet Sci 9:934273
DK · 2025 (brachycephalic)
open access37.6-40.1%
Brachycephalic breeds
35,121 Danish Kennel Club litters (2013-2022); population-level data confirms the brachycephalic burden and documents a rising trend through 2020.
Theriogenology 249:117663
DK · 2025 (all pedigree dogs)
12.7-15.5%
Overall pedigree rate
The same study's all-breed baseline: roughly 1 in 8 pedigree litters delivered surgically, making brachycephalic breeds 2.5 to 3x the population average.
Theriogenology 249:117663 · Secher et al. 2025
Brachycephalic skull morphology produces disproportionately wide, dome-shaped craniums. During parturition, the fetal head must rotate and pass through the maternal pelvic canal. When the biparietal diameter of the skull (the widest transverse dimension) exceeds the conjugate diameter of the pelvic outlet, vaginal delivery becomes mechanically impossible - a condition known as cephalopelvic disproportion (CPD).
Selective breeding for extreme brachycephaly has widened the skull relative to body size without a corresponding change in pelvic dimensions, making CPD increasingly common in the most extreme phenotypes. The result is that C-section is not merely common in these breeds; for many litters it is the only safe option.
Anatomical explanation per standard veterinary reproductive medicine; not derived from this dataset.
Skull biparietal diameter (red) exceeds pelvic outlet conjugate diameter (teal) - cephalopelvic disproportion
Population C-section rates cited from Secher et al. 2025 (Theriogenology 249:117663, 35,121 litters, Danish Kennel Club, 2013 to 2022). Abstract-level retrieval only; exact range-boundary definitions are not full-text-verified. Per-breed rates from Evans and Adams 2010 (J Small Anim Pract 51:113-118, UK Kennel Club 2004 survey, 22,005 litters) and Schrank et al. 2022 (Front Vet Sci 9:934273, CC BY).
Quick reference
Methodology and sources
Sourcing
Every figure on this page is drawn from a cited, independently retrieved source and was validated against it. We publish no internal or unverified estimates: where the peer-reviewed record has no figure for a breed, the page shows “No published data” rather than a guess. Our breed roster, slugs, and groups are used only to organize the study; they are not a data source.
Of 201 breeds in the roster, 48 have no published figure for either metric and appear as “No published data” at reduced opacity by design. These are not omissions to fix; they reflect the limits of the peer-reviewed record.
How to read the numbers
Litter-size figures are from Borge et al. 2011 and count total puppies born, including stillborns; the dispersion shown is the standard error of the mean, not a standard deviation. C-section figures are per-breed proportions from Evans and Adams 2010 (UK Kennel Club, 22,005 litters), with the German Shepherd Dog from Schrank et al. 2022. Population-level C-section context is from Secher et al. 2025; where O'Neill / VetCompass figures appear they are odds ratios given dystocia, not population rates, and are labeled as such. Hip and elbow dysplasia prevalence from Oberbauer et al. 2017 comes from the OFA voluntary database, which carries a known submission bias and may understate true population rates.
Confidence legend
Each data row carries one of three confidence levels:
Six breeds carry single-source confidence: German Shepherd Dog (Schrank 2022, n = 22), Toy Poodle, Pharaoh Hound, Pyrenean Shepherd, Wire Fox Terrier, and Toy Manchester Terrier. Their values are published with sample size visible and should be treated with additional caution.
Companion study: Pre-breeding health testing requirements by breed
| Source | Citation | Sample | Coverage |
|---|---|---|---|
| Evans and Adams 2010 | J Small Anim Pract 51:113-118 | 22,005 litters, UK Kennel Club 2004 survey | 143 breeds (C-section rates) |
| Borge et al. 2011 | Theriogenology 75:911-919 | 10,810 litters, Norwegian Kennel Club | 85 breeds (litter size, total born) |
| Schrank et al. 2022CC BY | Front Vet Sci 9:934273 | 899 litters, 80 breeds | 1 breed supplement (German Shepherd Dog C-section) |
| Secher et al. 2025 | Theriogenology 249:117663 | 35,121 litters, Danish Kennel Club | Population-level C-section context (abstract only) |
| Oberbauer et al. 2017CC BY | PLOS ONE 12:e0172918 | OFA records 1970-2015 (hip and elbow) | Hip/elbow dysplasia context, voluntary-submission bias noted |
Sources retrieved 2026-06-14. Evans 2010 and Borge 2011 values were extracted twice independently; only rows with exact agreement between both extractions are marked confirmed. The Secher 2025 figures are from the published abstract; full text was not retrieved.