If you have been consistent with training you should have a happy, well balanced, healthy GSD. Don't expect he or she to be good all the time though! Dogs will always have their slip ups and their cheeky streak, but that's why we love them right?
If you are adopting an adult GSD then things may be different. My mother adopted a one-year-old GSD/Doberman who was a terror. She was kept in a tiny flat, was allowed to roam around the city by herself and was not taught any basic commands. Consistent training with treats corrected this but please don't feel overwhelmed. There is help available. You can go to training classes and even get in a behavioural therapist. Know that all your effort will be worthwhile.
Feeding your adult GSD
Adult GSDs can be fed twice a day on good quality adult dog food. Always follow the manaufacturer's instructions on what amount to feed for size and age.
Keep an eye on his/her waistline! As they get older they will put on more weight.
Exercising your adult GSD
Just because your GSD is now an adult don't let up with the exercise. They can still enjoy a good run depending on whether or not they have any health issues.
Always remember to keep him/her on a lead in public areas.
Please do not walk your dog when it is too hot as it will lead to heatstroke. On hot summer days avoid the hottest times and walk in the morning and the evening. Always take water with you.
Your GSD and sleep
A normal healthy dog, not just a GSD, will sleep at different times throughout the day and night. They usually sleep between 12-14 hours over a 24 hour period. If your GSD sleeps more than this it is likely to be depressed and if it sleeps less than this it is likely to be over anxious.
The amount of sleep a dog gets directly affects its serotonin levels. Serotonin controls depression/aggression. Because of this it is a vicious circle and problems are likely to escalate.
You'll need to provide a good quality bed. Always have lots of room and comfort for your GSD. He/She should be able to lay on its side with its body and legs extended - this is to ensure it does not hurt itself during REM sleep. REM is essential for dogs as it processes the day's events and allows them to make new memories.
Make sure the temperature is appropriate. A GSD is a heavy coated dog and it is likely to over heat whereas a greyhound in cooler temperatures is likely to become too cold.
Always remember that dogs are happier sleeping together. Wild dogs always sleep in a pack. Dogs that sleep on their own may not feel comfortable or safe enough to sleep and this will impact them during the day. If you crate your GSD place the crate near your other dog(s) so that it feels safe and happy.
Your adult GSDs health
Continue to groom and brush its teeth. Check monthly for new lumps and bumps. My collie cross is now 12 years old and she has developed wart-like lumps on her body. Our vet has checked them and said they are fine. They look like little mushrooms but if they change they need to be checked out.
Take your GSD to the vet for its booster injections and continue with regular treatment for fleas and worms.
Training your adult GSD and its behaviour
Dogs are a lot calmer during old age. If your GSD has any behavioural problems they will be obvious by now.
If your GSD has behavioural problems seek help from a behaviourist.