Puppy food and adult food can look almost identical in the bowl, but they're built for very different jobs. Puppy food fuels a body that's growing fast, while adult food maintains a body that has finished growing. Feeding the wrong one for too long can cause problems either way. This guide explains what's actually different, why large breed puppies need special care, and how to tell from the label which food you're buying.
The key differences
1. More energy. Puppies can need around twice as many calories per kilogram as an adult dog of the same breed. Puppy food is more energy-dense, so a growing puppy can get what they need without eating huge volumes.
2. More protein. Protein builds muscle, organs and a healthy immune system. Under the AAFCO nutrient profiles that many pet foods are made to, puppy food needs a minimum of 22.5% protein, compared with 18% for adult food, on a dry matter basis.
3. More fat. Fat is a concentrated energy source and carries essential fatty acids. The minimum for puppy food is 8.5%, compared with 5.5% for adult food.
4. Carefully balanced calcium and phosphorus. Growing bones need more calcium and phosphorus than adult bones, and in the right ratio. Too little can weaken bones, and too much can be just as harmful, especially for big breeds.
5. DHA for brain and eyes. Many puppy foods add DHA, an omega-3 fatty acid found in fish oil, to support brain and eye development. That's useful for learning during training.
6. Smaller, softer kibble. Puppy kibble is usually sized for small mouths and baby teeth.
Why large breed puppies need their own food
Large and giant breed puppies, such as Labradors, Huntaways, German Shepherds and Great Danes, grow for longer, and their bones and joints are more sensitive to how fast they grow. Growing too quickly, or getting too much calcium, raises the risk of joint and bone problems later in life.
Large breed puppy foods are made for slower, steadier growth. They're usually a little lower in energy than standard puppy foods, with tighter limits on calcium. Under AAFCO, a food suitable for large breed growth must keep calcium below 1.8% on a dry matter basis. If your puppy will weigh over about 25kg as an adult, choose a food made for large breed puppies.
Can a puppy eat adult food?
It's not recommended. Adult food may not provide enough energy, protein or minerals for proper growth. The exception is a food labelled for all life stages, which is formulated to meet the needs of both puppies and adults. For large breed puppies, check that it specifically says it's suitable for the growth of large breed dogs.
Can an adult dog eat puppy food?
A few mouthfuls won't hurt. Long term, though, puppy food has more calories than an adult dog needs, which can lead to weight gain. One exception: pregnant and nursing mums often do well on puppy food, as they need extra energy and nutrients. Talk to your vet about feeding a pregnant dog.
How to tell from the label
Look for the nutritional statement on the bag, usually near the feeding guide. It should say the food is complete and balanced for one of these:
- Growth (or growth and reproduction): suitable for puppies.
- Adult maintenance: for adult dogs only.
- All life stages: suitable for puppies and adults. Check the wording for large breed puppies.
If the bag doesn't say, ask us. We're happy to check.
Puppy foods we stock
Black Hawk Puppy Large Breed Lamb & Rice. Formulated for puppies expected to weigh over 30kg as adults, for controlled, steady growth. Also available in Chicken & Rice, with added glucosamine.
Eukanuba Puppy Large Breed. High-quality animal protein with optimal calcium and phosphorus to help large breed puppies grow at the right rate. There's also Eukanuba Puppy Medium Breed.
Royal Canin Mini Puppy. Made for small breed puppies, with support for the immune system, brain development and gut health. Royal Canin also has Medium Puppy, plus breed-specific puppy foods including Golden Retriever, French Bulldog and Miniature Schnauzer.
Royal Canin Medium Starter Mother & Babydog. For mums during pregnancy and nursing, and for their puppies through weaning. Also available in Mini and Maxi sizes.
More puppy options. We also stock Addiction MEGA Large Breed Puppy, Pro Plan Large Breed Puppy and Small Breed Puppy, Hill's Puppy and Large Breed Puppy, Mighty Mix Nourish, and Maranui Ultimate Puppy Medallions for raw feeders.
Eukanuba, Royal Canin and Hill's are ordered in especially for you, so allow a few extra days. Not sure which suits your puppy? Call or pop into our Oxford store and we'll talk it through with you.
What about kittens?
The same principles apply. Kittens need more energy, protein and nutrients like DHA than adult cats. Feed a kitten food, such as Black Hawk Kitten, Hill's Kitten or Royal Canin Kitten, until around 12 months of age.
Ready to move on?
Our guide to when to switch your puppy to adult food covers the right age for each breed size and how to make the change.
Find the right food for your puppy
Browse our full range of dry dog food, with delivery across New Zealand and click and collect from Oxford, North Canterbury. Or get in touch and tell us about your puppy. We're happy to help you choose.
This article is general information, not veterinary advice. If your puppy is unwell, see your vet.