If your Newfoundland is having trouble walking around and staying mobile, call your vet to schedule an exam. Your pup may be simply developing signs of old age or he could be developing a joint or backend related illness like Degenerative Myelopathy. No matter the cause, your vet may recommend a mobility cart in addition to treatment associated with the diagnosed condition. Talk with your vet about the specific cart your pup will need and shop around to find the best brand and pricing. Carts can run anywhere from $100 to $400. Online stores such as K9carts.com offer brand new carts, used carts, and carts for rental purposes. Similar options may also be available at other retailers. Once you decide where to buy from, request a sales representative to help walk you through the process. You can also call your vet Portland, OR, or visit website http://portlandpetclinic.com/ for more additional assistance.