Growth spurts do in fact happen in Newfoundlands. In fact Newfoundlands can be 2 years old before they reach maturity, leaving you months of growth spurts to look forward to.
When Do Growth Spurts Happen
For larger breeds like the Newfoundland, puppies tend to grow steadily from birth until they are 5 to 6 months old. After this, their growth will slow and accelerate in cycles, just like human babies. During a growth spurt, your puppy will more than likely be hungrier than usual because his body is working hard to get taller and bigger.
Behavior Changes to Expect
The most noticeable thing you will notice in your puppy is the teething stage. When your Newfoundland is cutting teeth before he is a year old, you must provide him with adequate chew toys or you might find your puppy chewing on all manner of things that aren't made to handle puppy teeth. Keep chew toys on hand at all times and check them regularly for wear and tear. With your Newfoundland this is especially important because he is a breed with a large, powerful jaw that can wear out an average chew toy easily.
Changes in Diet During Growth Spurts
You puppy's nutritional needs change during growth periods. If you free feed your puppy, chances are he probably will eat until he is stuffed, which can cause him to grow too quickly. Overfeeding can lead to major health problems down the road for large breeds like the Newfoundlands, so make sure to check in with your vet regularly to see how much food he recommends for your pup according to his age, maturity and size.
Body Changes During Growth Spurts
During your Newfoundland's growth spurts, expect a sudden increase in height and weight. You might notice one day that your dog seems to be a few inches taller than he was a few days ago, and you probably are right. Growing spurts should level out around the time he turns 2.