Growth rates in puppies varies greatly depending on their size. It is important to tailor diet and exercise to your puppies specific requirements to ensure ideal skeletal development. Endochondral ossification (the process during which cartilage turns to bone) differs depending on the adult size of your puppy, with growth plates closing (complete ossification has occurred) between 3 months in toy breeds and 24 months in large breeds (see pictures).
There are many factors affecting growth rate and age of maturity, for instance males mature slower than females. There are variations in periods of ‘rapid growth’ ranging from from birth to 11 weeks in small and toy breed dogs to birth to 20 weeks in large breeds (Hawthorne et al 2004) excessive exercise and inadequate nutrition during these periods may result in conformation abnormalities and malformation of bones, which may lead to osteoarthritis and degenerative joint disease.Recommended exercise levels for puppies is 1 minute for every week of their life, twice a day. This should be low impact at a steady pace.
If you are aiming to train to compete for flyball or agility it is recommended that any jump training is avoided until complete ossification has occurred.
(Catherine Marshall Veterinary Physiotherapist)