When you pet a pup and sparkles and sometimes a yellow sparkle bone appears..

I have read that the bone increases your player points a tiny bit

That means that the dog has done something well like proformed a trick from a voice command tou can drag the bone to it's mouth and it will eat it

P.S. Has no effect to it's hunger

The bones increase loulty and when the the light buld pops over the dogs head fead that to the dog to and that will tell the dog he did the tricck right

When you pat your puppy, the sparkels mean that it is happy!

If you keep petting your dog and it sparkles until the bone give it to your dog and it is so happy

It actually means that you and your puppy have gained owner points. These points are used to unlock things like other breeds and items. If you see the sparkles go in Home and tap on your dog/cats profile on the bottom right. Then you click on the dogs picture. On the top right you can see a heart with numbers. These numbers are your owner points. You can get 200 a day but if you have 3 dogs/cats 600. Also, if you go into diary then click on the letter with your mii on the top screen are the total of owner points. I hope that this helped a lot!!