In the beginning you may see stools that are loose, odd or not happening. This is completely normal and natural when switching to a raw diet. You may see some soft, badly formed, oddly textured and/or oddly colored stool, sometimes with mucus. Dogs sometimes have trouble digesting raw food properly after being on highly processed commercial food and it takes a while for everything to start working properly. It is not unusual to have a day or two without a bowel movement. Once the digestive system has adapted, you will see stool that is firm, small, essentially odorless and quick to dry out and decompose.
If your dog is a new addition to your family, your dog may be experiencing the stress of a new environment, new people, etc. It's a very drastic change for a dog or puppy to go from how they've been living to a brand new home. For a puppies, it's especially stressful if they've just come from being with their mother, or brothers and sisters. Loose stools are often the result of stress and will subside after your dog becomes comfortable and feels safe in the new environment.