The question about whether to free feed your dog or provide food in scheduled meals is one of the most frequently asked questions I get as a veterinarian. From my search, I could find no scientific studies that shed good clinical data on the subject. As a clinician I do think that there is value in addressing the subject as I believe it can make a difference in your dog’s health, at least in certain circumstances.
According to a recent National Geographic article, domestic dogs descended from some ancestral wild canid, most likely gray wolves. If this is true would it not make sense that feeding one meal a day would more realistically imitate the natural feeding habits of dogs? As the article also points out however, there is abundant “morphological diversity” in modern dogs. It is this “morphological diversity” I believe that gives us cause to discuss the rationales for free feeding as opposed to scheduled meals.
A couple of weeks ago an adult Great Dane presented at the clinic late one evening with a condition called gastric dilation and volvulus (GDV). GDV is a life-threatening condition most common in large, deep-chested dogs in which the stomach fills with air and then twists, preventing the gas from escaping. One of the predisposing factors in this condition is thought to be rapidly ingesting a large meal. While there is no proven direct cause and effect between single meal feeding and development of DGV, I still recommend feeding scheduled meals at least three times a day, for large deep chested dogs, in an attempt to lower the incidence of GDV.
Last year I had an approximately one pound Yorkshire terrier puppy rushed into the clinic because it was drooling and staggering. This patient was suffering from hypoglycemia, a very common syndrome afflicting many small breed dogs. My recommendation to prevent hypoglycemia in small breed puppies is to free feed. Making sure that food is easily accessible at all times may help to maintain sufficient blood glucose levels, hopefully preventing this potentially life threatening situation.
As you can see there is no standard answer when deciding whether to free feed your dog or provide food in scheduled meals. This decision is best made based on the specific needs of your dog. Decisions are obviously based on consideration of number of factors including, breed, size, age and any medical conditions that may be affecting your dog. As always, consult your veterinarian for specific recommendations concerning your canine companions.
Source: How to Build a Dog by Evan Ratliff
National Geographic Magazine February 2012