English Mastiffs do require more food than the smaller breeds. We personally purchase premium dog food geared to the Large or GIANT breeds (please check the labeling-depending on the brand there may be NO difference between the 2 in terms of ingredients, but there may be on the cost because it's called "GIANT"). A good premium dog food contains less fillers – which means less work when doing poop patrol around the yard.
Your premium food should contain glucosamine, chondroiton, and a correct balance of the omega 3 and omega 6 acids. The glucosamine helps to increase flexibility and reduce joint discomfort in breeds that will grow to a man’s size in just a year’s time. It is a natural analgesic. It does not work immediately, but over time it promotes connective tissue efficiency and helps with joint regeneration by aiding the production of cartilage.
Chondroitin is thought to promote water retention and elasticity in cartilage. Together the two work to prevent cartilage degeneration. The omega 3 & 6 acids boost the immune system, increase blood flow to the tissues, and promote healthy skin and coats).
We personally use PMI Exclusive for large breeds. It IS made by Purina, although you wouldn't know it from the labeling on the bag. The ingredients are even better than the Purina ProPlan for Giant breeds, it costs about 15 dollars a bag less, and every 7th bag is free with their promotion. It is available at your local co-op. If not, ask them to order it for you. You can also log on to www.pminutrition.com and enter your zip code on the first page to see your closest dealer.
Veterinary care for an English Mastiff is the same as for any other dog, although dosages for medicines will obviously need to be increased. HOWEVER, not all vets are experienced with the GIANT breeds. Please ask your vet about his or her experiences with GIANT breeds. If they do not seem comfortable with your pet, find a new vet!
A good friend of ours passed on a horrifying story about a man who took his 2 Mastiff puppies into the vet because they were limping. Neither the man nor the vet knew that temporary lameness/limping is NOT AT ALL UNCOMMON in the GIANT breeds as they grow-particularly if they have over-exercised. The vet put both of the pups down. When the man later researched the breed, he was devastated not only by his decision to put the pups down, but by the inexperienced vet he had chosen. We were devastated just hearing about it!
Supplies are a bit more expensive for an English Mastiff. If you will crate train your puppy (which we strongly suggest), get the largest crate you can find and use a divider that can be moved as your puppy grows. You'll find that your pup puts him/herself in the crate on their own when they need a rest. Crates are MUCH cheaper online, we’ve found.

Puppies ROGUE & SADIE resting after a swim in the pool
Toys need to be made of tough stuff; ropes and heavy rubber work well, as do horse balls as they grow. We check out the pet stores’ sale aisles and stock up for when toys need replacing, which saves you a good 50% or more! Consider taking your pet with you. It is great socialization and they love to have a say in what you're bringing home.
PLEASE do not provide rawhide bones of any type though – they expand in the stomach and have been known to lodge in the throat. It is not worth the risk when so many other treats are available. Also, PLEASE do not use a choke chain. There are many good collars that will prevent pulling until your dog is trained. The old-fashioned choke chain can do permanent damage to the neck and throat.
