Saint Bernard nutrition, from slow puppy growth to bloat

Two feeding decisions carry most of the weight for a Saint Bernard. The first is to grow the puppy slowly, on measured meals, and never supplement its calcium. The second is where the food bowl sits: in a large study, about half of the cases of bloat in giant-breed dogs were attributed to feeding from a raised bowl. Everything else, from calories to joint care, comes back to keeping a very large dog lean.

According to the American Kennel Club, males stand 71 to 76 cm (28 to 30 in) and weigh 64 to 82 kg (140 to 180 lb), females stand 66 to 71 cm (26 to 28 in) and weigh 54 to 64 kg (120 to 140 lb), and life expectancy is 8 to 10 years.

Calories for a giant dog

Energy needs do not rise in step with body weight, which is why a 70 kg Saint Bernard eats far less per kilogram than a 10 kg terrier. The Merck Veterinary Manual gives the usual starting formula. Resting energy requirement (RER), in kcal per day, is 70 multiplied by body weight in kilograms raised to the power 0.75. An intact adult dog needs about 1.8 times RER, a neutered adult 1.6 times, and an adult that gains weight easily 1.4 times. Rounded to the nearest 5 kcal:

These are first estimates. Merck notes that animals of the same weight can differ by as much as 30% in what they need, and that breed matters independently of size: Newfoundlands, another heavy giant breed, appear to need fewer calories a day than Great Danes. A Saint Bernard with a quiet house life may well need the lower columns. Weigh the dog every few weeks on a vet clinic scale and adjust portions by about a tenth at a time.

Body condition is the real target. Ribs should be easy to feel under a thin layer of fat, and there should be a visible waist from above and a tuck behind the ribs from the side. On a heavily coated dog this has to be checked by hand.

Staying lean does more than spare the joints. In a lifelong study of 48 Labrador Retrievers, dogs fed 25% less than their paired partners lived significantly longer, and the onset of chronic disease was generally delayed. That study used a different breed, but the principle matters most in a breed whose life expectancy is already short.

Feeding a growing puppy

A Saint Bernard puppy has a very long way to grow, and the skeleton cannot be hurried safely. Two feeding mistakes make developmental bone and joint problems worse: too much energy and too much calcium.

Energy

In German growth trials, Great Dane puppies fed as much as they wanted during their first six months had more skeletal growth disturbances than puppies fed 70% to 80% of that amount. Fast growth produced angular limb deformities in both front and hind legs. Free feeding a giant-breed puppy removes that control.

Merck gives puppies about 3 times RER until four months of age and 2 times RER after that. For a 15 kg puppy under four months, that is about 1,600 kcal a day; for a 45 kg puppy over four months, about 2,430 kcal. Split the day's food into three or four meals while young, then two or three. Weigh the puppy regularly and ask the vet to check body condition at each visit. A lean, slightly slow-growing puppy is the goal, not the heaviest puppy in the litter.

Calcium

Merck describes excess calcium as a particular problem for large- and giant-breed dogs between weaning and one year of age. Diets supplemented above 3% calcium on a dry matter basis caused more severe osteochondrosis and decreased skeletal remodeling in young, fast-growing large-breed dogs. The practical rules follow directly:

• Feed a puppy food labeled complete and balanced for growth of large-breed dogs.
• Do not add calcium, bone meal or calcium-rich supplements to a complete food.
• Do not switch a giant puppy to an adult food early to slow growth. Control the amount fed instead.
• Be cautious with homemade diets. Merck notes that calcium deficiency has occurred in dogs fed high- or all-meat diets, and the calcium-to-phosphorus balance is easy to get wrong in either direction.

For dogs, Merck puts the optimal calcium-to-phosphorus ratio at about 1.2 to 1.4 to 1, within the AAFCO range of 1 to 1 up to 2.1 to 1. Growth diets must also contain at least 22.5% protein on a dry matter basis, against 18% for adult maintenance.

Bloat and GDV

Gastric dilatation-volvulus (GDV) is the emergency to know about. The stomach fills with gas and can twist on itself, cutting off its own blood supply and pressing on major blood vessels. In a prospective study of 1,914 dogs from 11 large and giant breeds, including the Saint Bernard, the giant breeds had 26 cases per 1,000 dog-years, and 28.6% of the dogs that developed GDV died. Risk rose with age.

A companion analysis of the same cohort found four factors that significantly raised risk: older age, a parent, sibling or offspring that had GDV, eating quickly, and a raised food bowl. The researchers attributed about 52% of GDV cases in the giant breeds to raised bowls. Raised feeders are widely sold for big dogs, which makes this the single most useful finding for owners.

• Feed from a bowl on the floor.
• Slow a fast eater with a slow-feeder bowl or by scattering part of the meal.
• Split the day's food into two or more meals rather than one large one.
• Avoid hard exercise straight after a big meal. This is sensible, though it has less evidence behind it than bowl height and eating speed.
• Ask the breeder whether any close relatives have had GDV.

Signs include a swollen or tight belly, repeated retching that brings nothing up, drooling more than usual, restlessness, pale gums and collapse. This is an emergency that needs a vet immediately, not a wait to see whether it settles.

Preventive gastropexy

A gastropexy fixes the stomach to the body wall so it cannot twist. It is often done at the same time as neutering. In a study of 61 dogs followed for a median of about two years after incisional gastropexy, none developed GDV, though about one in ten had later episodes of simple bloating without a twist. A gastropexy does not stop the stomach filling with gas, so a bloated dog still needs a vet, but it removes the twist that makes GDV so deadly. For a Saint Bernard, it is worth discussing with the vet before neutering.

Joints and body weight

Every extra kilogram on a dog this size loads the hips, elbows and knees, and body weight is the joint factor an owner controls completely. Keep the dog at a lean body condition from puppyhood onward, and let a growing puppy exercise at its own pace.

Joint supplements are sold heavily for giant breeds, and the evidence splits sharply. A 2022 systematic review and meta-analysis of 72 trials in dogs and cats with osteoarthritis found clear pain-relieving effects for omega-3-enriched diets and omega-3 supplements, and a marked lack of effect for glucosamine-chondroitin products, which the authors said should no longer be recommended for osteoarthritis pain. If a Saint Bernard shows stiffness, reluctance to rise or lameness, a vet examination comes before any supplement, since the dose and product matter and pain relief may be needed.

Drool, skin folds and water

Saint Bernards drool heavily, and food and water spread well beyond the bowl. A large washable mat under the bowls makes cleaning easier. Moisture trapped in the lip folds can lead to fold dermatitis, so wipe and dry the jowls after meals and check the folds for redness or smell.

Water should never be restricted. Merck gives the usual requirement for mammals as about 44 to 66 mL per kilogram of body weight a day, which for a 70 kg dog is roughly 3 to 4.5 liters. A noticeable rise in thirst with no change in weather or exercise is a reason for a vet check.

Sources

1. Saint Bernard dog breed information. American Kennel Club.
2. Nutritional requirements of small animals. Merck Veterinary Manual.
3. Effects of diet restriction on life span and age-related changes in dogs. Journal of the American Veterinary Medical Association, 2002.
4. The effect of a different energy supply for growing Great Danes on the body mass and skeletal development. 3. Clinical picture and chemical studies of the skeleton. Zentralblatt für Veterinärmedizin Reihe A, 1995.
5. Incidence of and breed-related risk factors for gastric dilatation-volvulus in dogs. Journal of the American Veterinary Medical Association, 2000.
6. Non-dietary risk factors for gastric dilatation-volvulus in large and giant breed dogs. Journal of the American Veterinary Medical Association, 2000.
7. Efficacy of incisional gastropexy for prevention of GDV in dogs. Journal of the American Animal Hospital Association, 2013.
8. A 2022 systematic review and meta-analysis of enriched therapeutic diets and nutraceuticals in canine and feline osteoarthritis. International Journal of Molecular Sciences, 2022.