It is hard to tell from that one picture but you can buy a fine toothed comb and go over the fur with it. If they have lice, the comb will pick up eggs/adults. Have they been excessively itching recently? You can tell it is eggs and not bedding since the eggs, when pressed between your fingernails, will leave a blood speck. Treatment for lice is pretty simple so the faster you treat, the easier it is going to be.