Irish Wolfhound nutrition: growth, bloat and heart disease

The Irish Wolfhound is the tallest breed the American Kennel Club recognizes, and one of the shortest-lived. In a survey of Swedish Wolfhounds born between 2006 and 2008, median lifespan was 7.5 years, and males died younger than females. Heart disease, bone cancer, bloat and pneumonia are among the breed's main health problems. Feeding cannot change a dog's genes, but it does decide how fast a puppy grows, how much weight an adult carries, and how meals are served to a dog with a deep chest.

What shortens a Wolfhound's life

A review of lifespan and disease in the breed found mean lifespan estimates ranging from about 5 to almost 9 years, depending on the population and how the data were collected. The same review lists the problems reported most often:

• Dilated cardiomyopathy (DCM), in which the heart muscle weakens and the chambers stretch
• Osteosarcoma, an aggressive bone cancer that usually starts in a leg
• Gastric dilatation-volvulus (GDV, or bloat), where the stomach fills with gas and can twist
• Osteochondrosis, a disorder of cartilage and bone in growing dogs
• Intrahepatic portosystemic shunt, a blood vessel inside the liver that lets blood bypass it

The Swedish owners' survey adds respiratory disease. There, the most common causes of death were cancer (24%), heart disease (18%) and respiratory disease (16%).

Heart disease and what diet can do

According to Swedish insurance data cited in the Swedish Wolfhound study, Irish Wolfhounds are 29 times more likely to die of heart disease than the reference breed, and DCM in the breed has been shown to be hereditary. That matters for how to think about supplements. Taurine and L-carnitine are often sold for heart health, but the Wolfhound's form of DCM is inherited, and no study has shown that adding either one prevents it. Doses should come from a vet, not a label.

Grain-free food is a separate question. In 2018 the US Food and Drug Administration began looking into reports of DCM in dogs eating diets, many labeled grain-free, with peas, lentils, other pulses or potatoes high on the ingredient list. The FDA has said that case reports alone cannot establish cause, and in December 2022 it stopped issuing updates until there is meaningful new science. For a breed already at high genetic risk, a conventional, grain-inclusive diet from a manufacturer that does feeding trials avoids adding an open question on top of a known one.

Regular heart checks have better evidence behind them than any supplement. An irregular rhythm called atrial fibrillation can appear before the heart itself looks abnormal on ultrasound. In a study of 645 North American Wolfhounds screened for heart disease, atrial fibrillation and being male both predicted later cardiomyopathy. Finding disease before symptoms also changes treatment. In a blinded trial in Wolfhounds with early DCM or atrial fibrillation, dogs on pimobendan went considerably longer before heart failure or sudden death than dogs on benazepril or methyldigoxin. Ask the vet or a veterinary cardiologist about regular ECG and ultrasound checks for an adult Wolfhound. Signs such as coughing, fast breathing at rest, fainting or reduced stamina need a vet promptly.

Daily calories by body weight

The Merck Veterinary Manual gives the usual starting point. Resting energy requirement (RER), in kcal a day, is 70 times body weight in kilograms raised to the power 0.75. That number is multiplied by a factor: 3 for puppies under 4 months, 2 for older puppies, 1.8 for an intact adult, 1.6 for a neutered adult and 1.4 for an adult that gains weight easily. Rounded to the nearest 5 kcal:

A 20 kg puppy under four months works out at roughly 1,985 kcal. These figures are estimates. Merck notes that dogs of the same weight can differ in what they need to hold that weight, and a quiet adult may need less than the table suggests. The scale and the feel of the ribs decide the portion. Convert calories to grams using the kcal per kilogram printed on the food, since two dry foods can differ a great deal in energy density, and that is also what sets the monthly food bill.

Growing a giant puppy slowly

Wolfhound puppies put on weight fast, and the skeleton is under strain while it does. Osteochondrosis is one of the problems the breed review lists most often. The aim is a steady growth curve and a lean puppy, not the biggest puppy in the litter.

• Choose a food labeled complete and balanced for growth of large-size dogs. The wording on the label shows the food was formulated for the growth of large dogs rather than puppies in general.
• Do not add calcium. Merck reports that in young, fast-growing large-breed dogs, very high dietary calcium (over 3% of dry matter) produced more severe osteochondrosis and poorer bone remodeling than diets with 1% to 3%. A complete puppy food already contains what the puppy needs, so supplements only push the total up.
• Feed for a lean body. Ribs should be easy to feel under a thin layer of fat, with a visible waist from above. Cut the portion if the puppy starts to look round, even if the feeding chart says otherwise.
• Split the day into several meals. Three or four meals for a young puppy, dropping to two or three as it grows, keeps each meal smaller.

Joint supplements are widely sold for giant breeds. They are optional, and they do not make up for a puppy that grows too fast or carries extra weight.

Bloat and how meals are served

GDV can kill within hours. In a prospective study of large and giant breed dogs that included Irish Wolfhounds, risk rose with age, with a close relative that had bloated, with fast eating and with a raised feeding bowl. The authors attributed about half of the cases in the giant breeds to raised bowls. Raised feeders are often sold for tall dogs as easier on the neck, so this is worth knowing.

In practice:

• Feed at least two meals a day rather than one large one.
• Put the bowl on the floor.
• Slow a fast eater with a puzzle bowl or by scattering kibble on a mat.
• Keep hard running and play away from mealtimes. This is standard advice, although it has been studied less than bowl height and eating speed.

Preventive gastropexy, in which the stomach is stitched to the body wall so it cannot twist, is worth discussing with the vet, often alongside other planned surgery. It does not stop the stomach filling with gas. A dog that retches without bringing anything up, has a swollen or tight belly, drools heavily or cannot settle needs an emergency vet at once.

Bone cancer, weight and neutering

No diet has been shown to prevent osteosarcoma. Keeping the dog lean is still worthwhile, because every kilogram of extra weight loads joints that already carry a lot. The breed review also discourages routine castration of male Wolfhounds, since it has been associated with a higher osteosarcoma risk. Timing of neutering is a decision to make with the vet, weighing that risk against others.

Watch for lameness that does not settle within a few days, or a firm swelling on a leg, particularly near the wrist, shoulder or knee. Either needs a vet visit and usually an X-ray, not a wait-and-see approach.

Pneumonia and liver shunts

Pneumonia is common in the breed. In the Swedish survey, 37% of dogs had pneumonia at least once, and more than half of those had it again. No food or supplement has been shown to reduce that risk. What helps is catching it early. Coughing, fast or labored breathing, fever, a runny nose or a dog that suddenly stops eating should be seen by a vet the same day.

Intrahepatic portosystemic shunt is inherited in some Wolfhound lines. A puppy that grows poorly or behaves oddly, especially after eating, should see a vet, who can check liver function with blood tests. If a shunt is found, any change in diet, including protein level, belongs in the treatment plan the vet sets, not in a home experiment.

Sources

1. Occurrence of cardiorespiratory diseases and impact on lifespan in Swedish Irish Wolfhounds: a retrospective questionnaire-based study. Acta Veterinaria Scandinavica, 2017.
2. Lifespan and disease predispositions in the Irish Wolfhound: a review. The Veterinary Quarterly, 2007.
3. Echocardiographic and electrocardiographic evaluation of North American Irish Wolfhounds. Journal of Veterinary Internal Medicine, 2020.
4. Long-term outcome of Irish Wolfhound dogs with preclinical cardiomyopathy, atrial fibrillation, or both treated with pimobendan, benazepril hydrochloride, or methyldigoxin monotherapy. Journal of Veterinary Internal Medicine, 2016.
5. FDA investigation into potential link between certain diets and canine dilated cardiomyopathy. US Food and Drug Administration.
6. Nutritional requirements of small animals. Merck Veterinary Manual.
7. Non-dietary risk factors for gastric dilatation-volvulus in large and giant breed dogs. Journal of the American Veterinary Medical Association, 2000.
8. Irish Wolfhound dog breed information. American Kennel Club.