
Natures Menu is a fabulous product that you are using for your oldie! It will be fantastic for your puppy too.
Your new puppy will be fine if you feed an adult product, it is usually just the mince size that determines puppy from adult. Remember to give your puppy a raw chicken wing twice a week or so to be sure of a good calcium intake and teeth cleaner.
Very firm/hard poo's are quiet normal with an all meat raw diet, it is not a bad sign as it helps express the anal glands and keeps them healthy, however sometimes a very white crumbly poo is produced after eating a large amount of bone, (not a problem) it will change again when normal food is resumed. Adding veg is perfectly fine.
Natures Menu are backed with advice from an absolutely fantastic vet "Nick Thompson" who strongly believes in a natural raw diet.
Stick with a product that you know and are happy with your puppy will be fine too.