When Does a Dog Count as Senior?

Ageing arrives at very different speeds depending on size. A Great Dane may be entering his later years at five or six, while a Jack Russell terrier might not need senior adjustments until nine or ten. As a rough guide, small breeds under 10 kg are usually considered senior from around eight, medium breeds from seven, and large or giant breeds from five or six. The exact number matters far less than what you're seeing day to day: slower rises from the sofa, a greyer muzzle, stiffness after a long walk, or a dog who once cleared the stile now asking to be lifted. Once those signs appear, it's worth reviewing the bowl as carefully as you review the walk.

Protein Still Matters — But Quality Comes First

A common myth is that older dogs need less protein. In truth, senior dogs need good quality, highly digestible protein to hold on to lean muscle, which is steadily lost with age. What changes is how well they extract it from their food. Older digestive systems and kidneys cope less well with heavy, fatty meats, so lighter sources often suit better:

• White fish such as cod, haddock or pollock, poached with no seasoning
• Turkey or chicken breast, skinned and cooked plainly
• Eggs, scrambled or hard-boiled, easy to chew and simple to digest
• Cottage cheese or plain yoghurt in small amounts, if dairy suits your dog
• Commercial senior diets listing a named meat or fish first, rather than "meat and animal derivatives"

Aim for a food that provides roughly 25–30% protein on a dry matter basis, but always confirm the right level with your vet, especially if your dog has kidney or liver issues where protein may need careful management rather than simple reduction.

Joint-Supporting Nutrients Worth Including

Stiffness and reduced mobility are among the most common reasons older dogs slow down, and diet can genuinely help. The most useful additions are omega-3 fatty acids from fish oil, particularly EPA and DHA, which support joint comfort and can help with inflammatory conditions. A typical starting point is 40–60 mg of combined EPA and DHA per kilogram of bodyweight daily, though higher doses are sometimes used under veterinary guidance. Look for a fish oil with a clear EPA and DHA figure on the label, not just "fish oil" by weight.

Glucosamine and chondroitin are widely included in senior diets and supplements, often in the region of 20–30 mg of glucosamine per kilogram daily. Evidence is mixed, but many owners report an improvement. Green-lipped mussel and MSM are other common additions. Introduce one new thing at a time, give it six to eight weeks, and judge by whether your dog moves more easily rather than by the label's promises.

Getting Portions Right

Metabolism slows with age, and most seniors need 10–20% fewer calories than they did in their prime. Overfeeding is far more damaging than a slightly lean dog, because extra weight loads already aching joints, worsens breathing and shortens comfortable walking distances. Do this properly:

• Weigh food on kitchen scales rather than guessing with a mug or scoop
• Check body condition monthly: ribs easy to feel without pressing, a visible waist from above, no heavy fat pad over the hips
• Weigh your dog at the vet every few months and record the number
• Count treats as part of the daily ration, and swap rich biscuits for small pieces of carrot, apple or plain cooked chicken
• Split the daily amount into two or three smaller meals if your dog seems uncomfortable or sluggish after eating

Digestion, Hydration and Daily Comfort

Older guts are often slower and more sensitive. A little added fibre — a tablespoon of cooked pumpkin or mashed carrot, or a spoonful of plain cooked oats — can settle loose stools or mild constipation. Probiotics may help after antibiotics or during stressful changes. Water matters just as much: seniors dehydrate more quickly, so keep bowls in several places, refreshing them twice daily, and consider adding warm water to dry food or mixing in a little wet food. On countryside walks, carry water and a collapsible bowl, and stop your dog scavenging discarded food, which can trigger a nasty upset.

Adjusting the Plan Over Time

Any change of food should happen gradually over seven to ten days, mixing increasing amounts of the new diet into the old. Keep a simple note of what you feed, how much, and how your dog seems — energy, stools, stiffness, appetite. Bring that record to your vet at least twice a year, or sooner if you notice weight loss, a sudden change in drinking, persistent bad breath or reluctance to walk. Ageing isn't a single decline to manage, but a series of small adjustments. Get the food right, keep the portions honest, and your old friend has the best possible chance of a comfortable, steady, well-fed retirement.