When our dog (1 1/2 year old beagle) runs she sometimes skips with her back left leg. I thought she was just a really happy pup and this was just one more cute thing that she does but someone told me that it could be a problem wit her back legs. She's not in any pain (at least she's not showing any signs of discomfort)... any ideas?

It could be some sort of a hip problem. I have even heard that hip dysphasia is creeping down into smaller breeds. Often a younger dog can make up for poor joint structure with good muscle tone. As the dog ages, problems shows up. Yours could be a borderline case. You should mention it to the vet the next time you are in. I doubt it is anything that needs immediate attention.

I have seen a number of puppies that didn't show any problems, be rejected by the dog guide school when they were X-rayed at a year old. The can't afford to spend the price of a fine car on a dog that will have its career shortened by hip troubles. I think it is less common now than in the early 90's. I think the breeding and nutrition is making a big difference.