There are several factors that come into play when determining a puppy's future size. Paw size is a helpful tool, it is not 100 percent reliable. It is unlikely that a small breed is going to have Michael Jordan paws. Consult with a veterinarian to help determine the size.
Big Parents, Big Puppies
The best way to determine the future size of your puppy is to look at both parents. The parent's breed, size and weight give you a good idea of what's in store for a small puppy. Large dogs are going to breed large offspring and the size of the puppy's paws doesn't mean that puppy is going to be the giant or the runt of the litter. The mother of the puppy will give you the best estimate of how big the dog will be.
Size Matters in Feet and Puppies
A larger breed needs bigger feet to support height and a heavier build, so this is where paw size comes into play. In additional to paw size, excess skin also can determine the size potential. The more loose skin the puppy has, the more room he has for growth. If you're looking at an older puppy, the puppy has reached approximately 75 percent of his adult height around 6 months of age because the long bone growth plates close between 8 to 11 months of age. Once these bones close, growth in height and length stops, but the dog can grow heavier since most dogs who weigh more than 55 pounds do not reach their adult size until 12 months.
Mixed Breeds Produce Varied Size
A puppy's adult size can be difficult to predict if the parents are unknown or the mixed breeds of the parents are unknown. This is often the case when adopting a mixed puppy from a local shelter. There are canine DNA testing services online that cost less than $100. These tests determine which breed the majority of your dog's physical traits will develop from, as well as the breeds in your dog's bloodline with physical traits unlikely to show unless they're dominant traits. Once you know where most of your dog's bloodline comes from, the American Kennel Club's website can give you the expected weight range and height for the breeds. If the puppy's paws are large and the dominant breed is a large breed, it's likely he'll be a large adult.
No Science in Predicting Size
If you look at the puppy's height and weight between 14 to 16 weeks of age, you can estimate the puppies adult size by doubling the current size. There is no exact science behind this method, but it does give you a better size prediction than just looking at the puppy's paws.
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Writer Bio
Melissa McNamara is a certified personal trainer who holds a Bachelor of Arts in journalism and communication studies from the University of Iowa. She writes for various health and fitness publications while working toward a Bachelor of Science in nursing.