Pets' corner: Why is my Jack Russell chewing soil?

My 13-year-old Jack Russell cross sometimes digs up and chews shallow soil when we are out for walks - she never does this in the garden at home. She has a healthy appetite. I'm increasingly concerned about this behaviour. Should I be adding something to her food? Harriet Craven, via email

Mud munching is a common problem in canines. The first thing we've got to rule out is the dietary imbalance. If your dog is not getting the right minerals it may be eating the soil to try and complement the nutrients it's lacking. As our beloved pooches get older, they need different vitamins. Also notice that your dog's metabolism may have changed, which makes it more difficult to get everything it needs from her food.

You need to go to the vets and discuss if there is a more suitable diet or some vitamins that will enhance your Jack Russell's digestive system. As you know, JRs are bundles of fun and they need lots of exercise and entertainment. If we don't give them entertainment, they will go and find it for themselves. These can include great terrier games such as chasing squirrels, wading into duck ponds, eating mud and digging holes – which they were originally bred for, amongst other things. This is quite a big part of a dog's life! They love to dig! As long as your dog is healthy and it's not giving her diarrhea or making her sick, don't worry and let her have the enjoyment!