Your First Great Dane
Great Danes are a magnificent breed, more refined than a mastiff, though they probably have fighting mastiff in their background. Careful socialization of puppies is very important with a dog of this size, both with humans, and you need to find them puppy playmates who are robust enough with withstand their strength.
Training should start from when they are pups, since it's easier to teach them the rules while they are small. Well-trained and well-socialized Great Danes are generally friendly with people they are introduced to by their owners, and are still capable of looking serious with uninvited guests. It is counter-productive to try to teach them to be guard dogs. Few intruders would want to walk past a Great Dane standing in their path, even if the dog looked friendly.
Some Great Danes are can be dog aggressive, especially entire males with other entire males, though this breed can be very tolerant of smaller dogs that bark or yap at them, worried by their large size. Great Danes are not an ideal breed for people with more than one dog, since they need more than average handler skill in multi-dog households, though if you have a Great Dane and want to take on a second dog, the safest thing to do is to allow your dog some say in who he or she lives with. This has benefits other than ensuring that your new dog is well matched with your Dane - dogs often dislike other dogs with 'issues', or bad manners, so the chances are that your Dane will weed out problem dogs for you. Taking on two Great Danes of the same sex is an especially difficult task, so is not recommended. Careful selection of pups for a calm temperament should help ensure your Great Dane has the potential to get on well with other dogs. Ongoing socialization with calm, older dogs as well as other pups, will build on this so that your Great Dane gets on with other dogs on walks and in training classes. You may still find your dog does not like some other dogs, and will need to avoid areas with a high density of dogs, walking early, for example.
Generally the breed is tolerant with children, though supervision is important. Children should respect Great Danes, and never tease them or encourage them to indulge in rough play indoors when they are pups. Great Danes can cause a lot of mayhem when they are in a boisterous mood! It helps to include older children in obedience training programmes, so that the dogs will lie down and obey other basic commands if the children ask them to. Great Danes can be quite barky dogs, especially if left alone a lot or bored. Their bark is very deep, so they are very good watchdogs.
They don't need a lot of grooming. They do need exercise, but of the right kind. As with all giant breeds, youngsters should not be allowed to over-exert themselves, so long periods of mad running around and jumping are not a good idea, and it's a good idea to give them a rest after they have been running around. Youngsters may also need rests on walks. Adults really need a daily walk, which means that obedience training is important so that you can trust them not to pull the lead out of your hand in public places.
Common health problems include heart trouble, hypothyroidism, arthritis, cancer, including bone cancer, and hip problems. As large-breed dogs, Great Danes are also vulnerable to bloat, and their food and exercise should be carefully regulated while they are growing.
Angela Mitchell's book is an excellent introduction to the breed, which is ideal for novices. It's very funny, as well as very informative, and prepares you for what is to come, if you own a Great Dane puppy. It can also be very helpful as a reference book for preventing problems.