Before asking what nutrients a working dog needs, we first need to ask: what are we asking the dog to do?
A sled dog travelling tens of kilometres, a gundog working intermittently throughout the day, a detection dog searching for scent are all “working” dogs. But they are not placing the same demands on their muscles, cardiovascular system or energy metabolism.
This is one of the problems with working-dog nutrition. Much of the research comes from extreme canine athletes, particularly racing sled dogs and greyhounds. Those findings are useful, but they should not automatically become feeding rules for every active dog.
Before we start, it’s worth defining what a working dog is:
A working dog is any dog regularly performing purposeful physical or mental activity, from sledding, herding, retrieving, hunting and detection work to canine sports such as canicross, obedience, agility, flyball, hoopers, protection and mantrailing.
We can then use the research to understand how these dogs fuel exercise, then adjust the diet according to the work being performed.
Dogs fuel exercise differently from us
Muscles need a constant supply of energy to contract. Because they can only store a small amount, the body continually needs to regenerate using fuels including glucose and fatty acids.
Dogs have an impressive capacity for using fat as fuel. Research suggests that, relative to metabolic body size, dogs can metabolise free fatty acids at around twice the rate observed in humans. This is one reason human sports-nutrition advice does not always translate well to dogs.
However, dogs do not simply "burn fat instead of carbohydrate".
Exercise intensity changes the fuel being used. Research has estimated that fat may provide around 60% of energy at 40% of maximal oxygen uptake, while glucose may provide around 80% at 85% of maximal oxygen uptake.
TLDR:
Longer, steadier work increases reliance on fat. Harder, faster work increases reliance on glucose and muscle glycogen. Your dog who is out working for 8-hours of the day could place more reliance on fat. Your flyball dog could place more reliance on glucose and muscle glycogen. These are just points to note, dogs don’t often read the textbook!
Duration, intensity, training status, temperature and how quickly the dog needs to work again all influence its nutritional needs.
Protein: supporting repair and adaptation
Protein is often discussed in relation to building muscle, but amino acids are also required for tissue repair, enzymes, transport proteins and many metabolic processes. Exercise changes protein turnover, so heavily exercised dogs may require more protein than sedentary dogs.
Early research in racing sled dogs found that haematocrit (the percentage of your blood that is made up of red blood cells) declined during training when dogs received 28% of their energy from protein, whereas this was not seen when protein provided 32% or more.
Researchers described this as training or "sports" anaemia.
But more protein is not automatically better. In racing greyhounds, dogs actually ran slower when dietary protein increased from 24% to 36% of energy.
These older studies should not be treated as precise feeding recommendations. What they demonstrate is that protein requirements depend on workload, total energy intake and the type and quality of protein provided.
Practical takeaway
Prioritise good-quality, digestible animal proteins rather than simply adding large amounts of extra protein. Meat, fish, eggs and appropriately selected organs provide amino acids alongside useful micronutrients.
If workload increases substantially, the dog's overall food intake and protein provision may need to increase too.
Fat: a major fuel for canine endurance
Fat is particularly important for dogs undertaking prolonged work.
In one study, Beagles eating diets providing 53–67% of their energy from fat ran for around 20 miles before exhaustion. Dogs receiving 29% of their energy from fat became exhausted after around 15 miles.
Research in sled dogs has similarly shown the usefulness of high-fat diets during demanding endurance exercise.
Fat is energy dense and dogs are highly capable of using fatty acids. Training and diet can further increase this capacity. A simple equation may be to consider how many miles you think your dog covers in a day. This may give you an indication of where your dog falls in terms of “endurance.”
However, extremely high-fat feeding is not necessarily ideal for every sport. Greyhound research suggests more moderate fat intake may suit short, high-intensity sprinting better.
Practical takeaway
For dogs doing longer duration work (like a full day), increasing dietary fat can be a useful way to increase energy intake without dramatically increasing food volume.
Suitable foods might include fattier cuts of meat, oily fish, eggs and other animal foods.
Strategies to try:
Offer oily fish in more meals,
Opt for duck or lamb proteins,
Add tallow to meals,
Remember to increase fat gradually. A sudden jump in dietary fat can cause digestive upset, and dogs with medical conditions affecting fat digestion or metabolism require individual advice.
Does a working dog need carbohydrates?
Dogs have no established dietary requirement for carbohydrate, but glucose still plays an important role during exercise.
Dogs can manufacture glucose themselves and store glucose as glycogen in the liver and muscles. As exercise intensity rises, glycogen becomes increasingly important.
Interestingly, feeding more carbohydrate does not necessarily mean a dog finishes exercise with more glycogen. Sled dogs fed a high-carbohydrate diet had higher muscle glycogen before exercise than dogs fed a high-fat diet. But they also used that glycogen faster. By the end of the race, muscle glycogen concentrations were similar between the groups.
Dogs can therefore adapt their fuel use according to the diet they are eating.
Where carbohydrate becomes particularly interesting is recovery between demanding exercise sessions.
In a study of 24 trained Alaskan Huskies completing a 30 km run, dogs receiving a glucose polymer immediately afterwards restored muscle glycogen considerably faster than dogs receiving water. Four hours later, supplemented dogs had replaced approximately 49% of the glycogen used during exercise.
So rapidly available carbohydrate can accelerate glycogen replenishment. But that does not mean every working dog needs dextrose after exercise. Dextrose is rapidly absorbed and can cause a sharp rise in blood glucose and insulin, so while it may be useful for rapid increases in blood sugar, it is generally unnecessary for routine training or moderate activity.
Practical takeaway
For most moderately active dogs, there is little reason to automatically give sugar after every training session. During periods of harder training, digestible whole-food carbohydrates such as oats or mashed potatoes can be incorporated into the diet where appropriate. This may be particularly useful for working gundogs for example.
Rapidly available sugars have a more specific role. Something such as honey may be useful when exercise has been particularly prolonged or demanding and the dog needs to perform again before normal feeding and recovery would fully restore glycogen. This may be particularly useful for those flyball or canicross dogs.
Think of carbohydrate according to purpose:
Mashed potatoes and oats at usual feeding times may support harder and longer training periods. Rapid sugars like honey are tools for situations where rapid refuelling is actually required (on the day).
Examples of strategies to try:
- Mashed potato or oats offered around working days
- Honey during working days
This could apply to working gundogs, flyball, agility, canicross and detection.
Note: for dry-fed dogs, the carbohydrate already present in the diet can be useful for supporting glucose availability and restoring glycogen after exercise. Many dry foods provide a meaningful amount so additional carbohydrate may only be needed when the dog's workload and recovery demands justify it.
Micronutrients: supporting the machinery
Exercise also depends on vitamins and minerals.
Iron is required for haemoglobin and myoglobin, helping transport oxygen through the blood and muscle. Copper contributes to iron metabolism and haemoglobin formation, while B vitamins participate in pathways that release energy from protein, fat and carbohydrate.
Muscle contraction and nerve signalling depend on minerals including calcium, magnesium, sodium and potassium.
Exercise also places mechanical stress on muscle, connective tissue and bone. Zinc supports protein synthesis and tissue repair, while copper and manganese contribute to connective-tissue biology. Calcium and phosphorus are fundamental to bone.
This does not mean working dogs should automatically receive mineral supplements.
Calcium is a good example. Adding more calcium does not simply create stronger bones. Excessive or poorly balanced calcium can interfere with skeletal development.
A well-considered diet should provide these nutrients in appropriate amounts and ratios before individual supplements are considered.
What about electrolytes?
Human endurance athletes can lose substantial sodium through sweat. Dogs regulate body temperature primarily through panting and sweat much less, so human electrolyte advice cannot simply be transferred to them.
Water turnover can still increase dramatically with prolonged work and heat. In racing sled dogs, reported water turnover increased from around one litre per day in kennelled dogs to approximately five litres per day during a 490 km race.
That is an extreme example, but it demonstrates how dramatically hydration requirements can change.
For most active dogs, access to water and appropriate hydration strategies should come before automatically adding “electrolyte” supplements.
Useful reads:
How Dogs Stay Cool: Understanding Canine Thermoregulation
Hydration: The Foundation of Cooling, Performance and Recovery
Why Some Dogs Don't Drink Enough (And How To Encourage Them To)
Do working dogs need extra antioxidants?
Exercise increases oxygen consumption and the production of reactive oxygen species.
These molecules are often described simply as damaging "free radicals", but some reactive oxygen species also act as signals that help the body adapt to exercise.
The dog's own antioxidant systems depend on nutrients including selenium, zinc, copper and manganese. Vitamin E also helps protect cell membranes from damage.
This creates an important distinction between providing adequate antioxidant nutrients and giving large doses of antioxidant supplements.
For most working dogs, the aim should be a nutrient-dense diet that supports the dog's own antioxidant systems rather than attempting to suppress the normal response to exercise.
So, what could your working dog’s bowl look like?
Start with the work rather than the label "working dog".
For longer endurance work: energy requirements rise considerably and fat becomes particularly valuable. Focus on sufficient calories, quality animal protein, increased dietary fat and hydration. This may be for your dogs who work all day, or for those who participate in ultra-type events.
For shorter, harder work: glucose and glycogen become increasingly important. Food-based carbohydrates can be useful to consider. This can apply to dogs who work all day, but tend to work in short, hard bursts and then have some recovery time.
For repeated demanding work with limited recovery: rapid carbohydrate like honey after exercise may help restore glycogen more quickly. Again, this can apply to dogs who work all day, who are in and out of work but need to replenish quickly. It can also apply to your flyball, agility, canicross or racing dogs.
For recovery: provide adequate energy and high-quality protein, alongside a diet supplying iron, copper, zinc, selenium and B vitamins.
For supplements: start by asking what problem the supplement is intended to solve. Does your dog have that problem? If not, you probably don’t need that supplement.
The nutritional requirements of a dog running 5 km twice a week are not those of a sled dog travelling 100 km. The useful question is therefore not simply, "What should I feed a working dog?"
Ask instead: How hard is my dog working, for how long, how often, and how quickly does it need to recover?
Once you know that, you can adjust energy, fat, protein, carbohydrate and hydration to match the actual work being performed. Look for changes in body composition, if they are losing or gaining weight you probably need to look again at the macronutrients (obviously once you have had any medical reason ruled out).
If all else fails, you know your dog better than anyone. Make a few tweaks and see if it moves the needle.
Lisa Hannaby-Aird
A Registered Associate Nutritionist and author of Nutrition for Dogs, Lisa combines expertise in nutrition, psychology, biochemistry, and neuroscience to help dog owners understand the science behind canine health, behaviour, and nutrition.