A Blenheim Cavalier King Charles Spaniel sitting on a soft rug in a bright kitchen
Breed Encyclopedia

Cavalier King Charles Spaniel

The Cavalier King Charles Spaniel is a gentle, affectionate toy spaniel with royal British roots that gets along with family, children, other dogs and even cats. It is just as happy on a walk as on the sofa, and because heart murmurs are common in the breed, regular veterinary checks and a trim body matter.

A Blenheim Cavalier King Charles Spaniel sitting on a soft rug in a bright kitchen

  • SizeSmall
  • AKC groupToy Group
  • Height12-13 in
  • Weight13-18 lb
  • Life expectancy12-15 years
Part A

About the Cavalier King Charles Spaniel

Origin and purpose

Cavaliers descend from the small "comforter" spaniels of European and English royal courts, made famous by Kings Charles I and II. The modern breed was revived in Britain from the 1920s on, and AKC recognized it in 1996. It has always been bred as a companion. (AKC history, ACKCSC flier, AKC fun facts, ACKCSC)

Coat and energy

The silky, moderately long coat has feathering and no curl (a slight wave is fine), and the standard does not allow trimming. There are four colors: Blenheim (red and white), Tricolor, Ruby, and Black and Tan. (AKC breed standard, AKC fun facts, ACKCSC)

Energy is moderate. AKC calls Cavaliers adaptable, happy with active owners or homebodies and as fond of walks as of lounging, and suggests keeping them leashed or fenced because of their sporting instincts. (AKC)

Nutrition and weight

Cavaliers gain weight easily: a UK study of veterinary records found them about 1.5 times as likely as crossbred dogs to be recorded as overweight. (RVC VetCompass)

With AKC standard weights of 13-18 lb, a few bites of a human-sized cookie can be a big share of the day's calories, so keep all treats under about 10% of daily calories. UK Cavaliers had a median maximum adult weight of 10.5 kg (about 23 lb), above the standard's range, so ask your veterinarian what a lean weight looks like for your own dog. (AKC breed standard, Tufts, VetCompass)

Once heart valve disease progresses, diet becomes part of veterinary care: ACVIM consensus guidelines address sodium intake, including sodium from treats, for dogs with more advanced disease. Follow your veterinarian's plan rather than changing the diet on your own. (ACVIM guidelines)

Health watch

  • Myxomatous mitral valve disease (MMVD): Gradual thickening and leaking of the heart's mitral valve; ACVIM guidelines say Cavaliers are predisposed to develop it at a relatively young age, and 30.9% of Cavaliers in UK primary-care records had a heart murmur recorded. For dogs with more advanced disease, the guidelines call for limiting sodium from treats and table food and avoiding processed or salted foods, so ask your veterinarian before giving salty bakes to a Cavalier with a murmur. (ACVIM guidelines, VetCompass, ACKCSC hearts)
  • Chiari-like malformation and syringomyelia: A skull malformation that crowds the back of the brain and can lead to fluid-filled cavities in the spinal cord; the Merck Veterinary Manual says it is commonly reported in Cavaliers, with signs such as face rubbing, "phantom" scratching, wobbliness and weakness, though many dogs with it on MRI show no signs. No specific treat link. (Merck: CM/SM, ACKCSC on SM)
  • Eye problems (dry eye and juvenile cataracts): The breed club flags juvenile cataracts and dry eye and asks breeders to screen for inherited eye defects; eye disorders affected 20.6% of UK Cavaliers in veterinary records, with dry eye among the most frequently recorded corneal problems. No specific treat link. (ACKCSC flier, VetCompass)
  • Patellar luxation (slipping kneecap): A kneecap that slips out of its groove; the Merck Veterinary Manual lists Cavaliers among breeds predisposed to the lateral form, and kneecap checks are recommended before breeding. No specific treat link. (Merck table, AKC health testing, ACKCSC flier)

Fun fact

The modern Cavalier owes its comeback to a prize: in 1926 an American, Roswell Eldridge, offered 25 pounds sterling at England's Crufts show for spaniels that matched the older, longer-nosed type. (AKC history, ACKCSC breed guide)

Part B

Baking, treats and ingredients

Breed-specific baking notes

  • Go easy on salt. Choose unsalted butter or skip butter, and avoid salty, cheesy savory bakes. Cavaliers are prone to early heart valve disease, and ACVIM guidelines call for limiting sodium, treats included, once that disease advances. (ACVIM guidelines)
  • Heart diet first. If your Cavalier is on a prescribed heart diet, check with your veterinarian before adding any homemade treats. (ACVIM guidelines)
  • Tiny portions. Break treats into fingernail-sized pieces for a 13-18 lb dog that puts on weight easily, and keep treats under about 10% of daily calories. (AKC breed standard, RVC VetCompass, Tufts)

General baking safety (all dogs)

  • Leave these out of every bake. Chocolate and cocoa (baking chocolate and cocoa powder are the most concentrated), coffee, espresso powder, caffeinated tea or anything else with caffeine, grapes and raisins, macadamia nuts, and onion, garlic or chives. If your dog eats any of these, contact your veterinarian or an animal poison control line, such as the ASPCA Animal Poison Control Center at (888) 426-4435, right away. (ASPCA)
  • Be honest about vanilla. Under the U.S. standard of identity, vanilla extract must contain at least 35% alcohol by volume, and the ASPCA lists alcohol as dangerous for pets. Leave alcohol-based extracts, vanilla included, out of dog treats, and check the label of any other flavoring for alcohol. (21 CFR 169.175, ASPCA)
  • Never use xylitol. The FDA warns it can crash a dog's blood sugar within 10 to 60 minutes and that it can turn up in sugar-free gum and candy, some peanut and nut butters, baked goods and sugar-free desserts, so read the label of every ingredient. If your dog eats xylitol, contact your veterinarian or an animal poison control line right away. (FDA)
  • Bake yeast dough all the way through. Keep raw dough out of reach: the ASPCA says raw yeast dough can expand in the stomach and makes alcohol as it ferments. (ASPCA)
  • Keep fat, salt and dairy modest. The ASPCA says fatty nuts such as almonds, pecans and walnuts can cause vomiting, diarrhea and possibly pancreatitis, that too much salt is harmful, and that many pets digest milk and dairy poorly. (ASPCA)

Daily calories and treat budget

A typical neutered adult at 13-18 lb needs roughly 424-541 kcal a day (RER x 1.6, Merck Veterinary Manual), so treats should stay under about 42-54 kcal a day (the 10% guideline). Intact, very active, young, senior or overweight dogs differ, so ask your veterinarian for your dog's number.

Check an ingredient before you bake, and see how to portion treats with the 10% rule.

Treat size: For a typical neutered adult Cavalier at 13-18 lb, keep treats under about 42-54 kcal a day, roughly 10% of daily calories.

Ask your veterinarian about

  • Mitral valve disease (MMVD)
  • Chiari-like malformation and syringomyelia
  • Dry eye and juvenile cataracts
  • Patellar luxation

Breed tendencies don't mean your dog has a condition. Your veterinarian knows your dog.

Ingredients to know

Sources

  1. Breed page (height, weight, life expectancy), American Kennel Club. Checked October 22, 2026.
  2. Cavalier King Charles Spaniel History: From Revived Hunting Dog to Popular Companion, American Kennel Club. Checked October 22, 2026.
  3. Congratulations on Your Cavalier King Charles Spaniel, American Cavalier King Charles Spaniel Club (AKC parent breed club), flier hosted by AKC. Checked October 22, 2026.
  4. Cavalier King Charles Spaniel Facts You May Not Know, American Kennel Club. Checked October 22, 2026.
  5. Defining the Cavalier, American Cavalier King Charles Spaniel Club (AKC parent breed club). Checked October 22, 2026.
  6. Official Standard of the Cavalier King Charles Spaniel, American Kennel Club. Checked October 22, 2026.
  7. Is the Cavalier King Charles Spaniel a Good Fit for You?, American Kennel Club. Checked October 22, 2026.
  8. Frequency, breed predisposition and demographic risk factors for overweight status in dogs in the UK (RVC news release), Royal Veterinary College VetCompass (reporting Pegram et al. 2021, J Small Anim Pract, doi:10.1111/jsap.13325). Checked October 22, 2026.
  9. Growth Guide: Keeping your Puppy on the Right Track, Tufts University Cummings School of Veterinary Medicine (Petfoodology). Checked October 22, 2026.
  10. Prevalence of disorders recorded in Cavalier King Charles Spaniels attending primary-care veterinary practices in England, Canine Genetics and Epidemiology (Summers JF et al., 2015; VetCompass). Checked October 22, 2026.
  11. ACVIM consensus guidelines for the diagnosis and treatment of myxomatous mitral valve disease in dogs, Journal of Veterinary Internal Medicine (ACVIM consensus statement; Keene BW et al., 2019). Checked October 22, 2026.
  12. Hearts, American Cavalier King Charles Spaniel Club (AKC parent breed club). Checked October 22, 2026.
  13. Congenital and Inherited Cerebellar Disorders in Dogs and Cats, Merck Veterinary Manual. Checked October 22, 2026.
  14. SM, American Cavalier King Charles Spaniel Club (AKC parent breed club). Checked October 22, 2026.
  15. Table: Heritable Conformational Conditions Resulting in Canine Osteoarthritis, Merck Veterinary Manual. Checked October 22, 2026.
  16. Toy Group Health Testing Requirements, American Kennel Club. Checked October 22, 2026.
  17. The Cavalier King Charles Spaniel Breed Guide (Revised 2011), American Cavalier King Charles Spaniel Club (AKC parent breed club), Judges' Education Committee; hosted by AKC. Checked October 22, 2026.
  18. People Foods to Avoid Feeding Your Pets, ASPCA Animal Poison Control Center. Checked October 22, 2026.
  19. 21 CFR 169.175 -- Vanilla extract., U.S. Food and Drug Administration regulation, published in the Electronic Code of Federal Regulations (eCFR). Checked October 22, 2026.
  20. Paws Off Xylitol; It's Dangerous for Dogs, U.S. Food and Drug Administration. Checked October 22, 2026.

Last checked against these sources: October 22, 2026.

Written by VanillaGoods from the cited sources. Not reviewed by a veterinarian. Not a substitute for veterinary advice.