Congratulations on Your New Rescue Giant!

First of all, your new rescue will take a while to adjust to its new home.  If you have other dogs in your home, it tends to be easier to introduce new dogs in a neutral location, like a park or the yard, rather than inside the house where your dogs will feel the need to protect their territory.

The first few days (or weeks) are the most difficult for most new adopters.  New dogs need time to adjust to your schedule and your other pets will take time to figure out the new dog’s position in their pack.  Female dogs tend to be territorial and protective of their pack and owners, whereas male dogs are territorial and protective of their territory (i.e. home, yard, and crate).

When same sexed dogs are in the same household there can be a conflict over what the dog perceives its job to be.  While your dog may be great with other dogs in a neutral situation like a dog park, this may not be the case when a new dog is introduced into your household.  This is one of the main reasons Rescue prefers to place rescue Giants with opposite sexed dogs.  It helps to reduce the likelihood of serious dog fights. 

Adult Giants tend to take anywhere between 4-6 weeks to relax and settle down in their new homes.  For some dogs it may take a year or more to fully relax and feel confident and safe.  During this time, they may not do the typical Giant things like barking, relaxing on the furniture, playing with toys, protecting, getting into things left unattended, counter surfing (if you are lucky).  They seem slightly aloof or distant with their new family.  This is normal for the breed. 

Many rescue dogs will have accidents in the house due to insecurity or a lack of knowing where the door is and how to tell their new family that they want out.  Both female and male Giants can be prone to spay/neuter or genetic urinary incontinence.  If the dog urinates in the crate, when they are laying down, or the leaking continues after the dog is adjusted to its new home, you may want to have your vet check the dog for urinary incontinence. 

Getting a new rescue dog to eat can sometimes be frustrating. Giants sometimes show their stress through their stomach, either with a loose stool or loss of appetite.  Again, that behavior is fairly typical for the breed.  Feeding the new dog in a crate without any other dogs nearby is a very good way of helping them to feel secure.  This will also reduce the chances of the dogs fighting over resources such as food.

The easiest way to deal with any new dog is to treat them as you would someone who moved here from a foreign country. Assume that the new dog does not speak your language and treat them as you would a puppy.  The words and commands that you use on your dogs may be very different than the previous owners used.  One person may like having their dogs on the furniture, while another may dislike that and it will take a while for the new dog to figure out what you want from it.  Having other dogs in the household will help a lot.  It gives the new dog a role model for what behavior is accepted. 

After the "honeymoon period," the rescue dog tends to start focusing on their new family and showing their true personality.  Spending alone time with each dog is always a good thing to do if you can.  Dogs being pack animals will tend to form bonds with the other dogs and it is to the owner's benefit to make sure that each dog has time to form a bond with humans on their own.  Taking a new dog through a training class is a great way of doing that.  It also gives you both of you time to learn each other's language and way of dealing with things. 

There are two techniques that many rescue people use with new dogs, "Leading The Dance" (http://www.shirleychong.com/keepers/archives/dance.txt) and "Nothing In Life Is Free (NILIF)" (http://www.goof.com/~pmurphy/NILIF.html).  Both work very well with this very alpha and terrier-like breed and can be used at anytime to establish the hierarchy in the household or if you are having problems with your dogs.  The new dog needs to earn its' position in your pack and the biggest mistake we all make is to try give them too much too soon.  We all do it at one point or another and then have to spend a great deal of time undoing the bad behavior that comes from spoiling them.