“He hath eaten me out of house and home...” This quotation from "King Henry the Fourth Part 2" was not in reference to a dog, but it may seem that way as more owners struggle to keep their pets looking like the corpulent Falstaff.
Avoiding obesity and its long-term damaging side effects may be the biggest problem a pet parent faces.
It would seem to be a simple matter to keep dogs lean, but that is not the case, considering that more than 54% are overweight and obese. The situation is perplexing because there are several factors involved with this problem, including pet parents being unaware of the ideal body condition of their pet. The pet food industry then must address this problem to help owners keep their dogs lean. In addition, the pet parent could save money just by reducing pet food consumption.
Often, the dogs are overfed as parents defer to their pets' appetite even when they are attempting to feed the right amount of food. Unintentionally overfeeding a dog can baffle owners who believe they are doing the right thing.
Feeding at maintenance
The objective of the pet parent should be to provide enough food to maintain the dog in a healthy body condition. For an adult dog, this means sustaining a constant bodyweight, which means feeding at maintenance levels. By definition, maintenance is the equilibration of metabolizable energy (ME) intake and heat produced by metabolism, according to the National Research Council (NRC), 1981.
The Nutritional Requirements of Dogs & Cats (2006) summarized research showing daily maintenance for dogs ranging between 94 and 183 kcal of metabolizable energy (ME)/W.75 (kg). One can expect a wide range in maintenance requirements among breeds due to resting energy metabolism, body conformation, hair coat, resistance to being idle and other factors. In addition, one must accept that experimental error among studies could lead to an exaggerated range in the perceived requirements for maintenance. The table shows estimated maintenance requirements for dogs at different bodyweights assuming relative low, medium and high requirements.
Bodyweight Low Moderate High
10 lb 280 310 340
25 lb 560 620 680
50 lb 935 1040 1145
75 lb 1270 1410 1550
*Maintenance requirements are expressed in kcal ME/day. Low, moderate and high maintenance requirements were established at 90, 100 and 110 kcal/day/W.75
How much to feed?
Typical feeding guidelines on a bag of pet food will provide a range of amounts of food (usually in cups) that should be given to a dog at a certain bodyweight. A range is given because the dietary energy requirements for dogs vary widely. Bodyweight is used as a criterion to establish feeding guidelines. However, there are differences in physical, activity and differences among breeds and even within lines of breeds based on age, sex and metabolism based on intense genetic selection over many years. Consequently, the maintenance requirements of two dogs with the same bodyweight may differ significantly. Given all these factors involved, it leaves the pet guardian to determine the proper amount of food that should be given to their dog. Essentially, the feeding guidelines are a starting point as the guardians must decide for themselves the necessary adjustments in the amount of food needed to keep the dog in an optimal body condition.
For dogs weighing 50 lb. the feeding guidelines, based on the Table, would imply that all dogs that need 935-1,145 kcal ME daily. Taking a food that is 400 kcal ME per cup, an acceptable guideline could show a range of 2.3 cups to 2.9 cups for the 50 lb. dog. What happens if an owner of a 50 lb. dog considers feeding the dog the middle of this range, 2.6 cups, while the maintenance requirement of the dog is on the low end? The owner could unintentionally provide the dog with an extra 120 kcal ME per day. This practice can potentially cause the dog to gain 8 lb. over the course of a year.
The generous owner
Another problem can arise when the owner feeds an overflowing cup of food when the feeding guidelines are designed for a heaping cup. Take an owner who perceives that the dog is provided with the correct amount of food to maintain bodyweight using a heaping cup. The resulting overflowing cup provides more food than needed -- let’s assume 10% more than needed for maintenance. Consequently, the 50 lb. dog will receive 10% more ME than required, which would result in weight gain of 6.2, 6.9 and 7.6 lb. based on the ME requirements from the low, moderate and high levels, respectively, (Table) over a period of one year.
Of course, ME intake can insidiously add up when treats are fed. Assume that a dog is given 10 g of treats daily that have an energy density of 3,200 kcal/kg. This amount might seem quite paltry to the owner. If the dog is given a food that is supplying enough ME for maintenance, however, the consumption of these treats can result in the dog gaining 2 lb. over a year’s time. This problem can easily be ameliorated by feeding treats with a lower energy density or making sure to account for treats as an additional source of ME. One can easily reduce the additional ME from the treats from the base food provided that the treats are nutritionally balanced.
To summarize, it is not hard for a guardian's dog to become over-conditioned. In many situations, the owner may be diligently attempting to keep the dog lean but unintentionally does something that nullifies the effort. Given the range in maintenance requirements, it is impossible for pet food companies to develop feeding guidelines with more precision than those currently in use.
The differences among dogs makes using bodyweight as the sole index for any feeding guidelines inadequate for precisely estimating maintenance requirements.
Down the road, some companies may be able to provide specific information concerning the maintenance requirements from information gathered from the genome of an individual pet. Until then, it is important to educate the pet guardian about the proper body condition score or some other index to keep their pet in good health. Pet guardians must also be informed about the limitations of feeding guidelines, be educated on how to properly provide food volumetrically and understand the contribution of feeding treats to dietary energy.
NRC. 1981. Nutritional Energetics of Domestic Animals. National Academy Press, Washington DC.
NRC. 2006. Nutrient Requirements of Dogs and Cats. National Academy Press, Washington, DC.
*Ron Rompala is director of nutrition for Cool Springs International, Franklin, Tenn., and adjunct professor at the University of New Hampshire. Juan Gomez-Basauri is global director, companion animal business, Alltech, Nicholasville, Ky.