Where does one turn to in Guelph for a safe and nutritious pet food?
All any of us want for our pets is to provide quality nutrition with minimal risk at a reasonable price. But how is one supposed to navigate a kaleidoscope of pet food advertisements and purported health claims, all amidst frequent recall alerts[i]? Not to mention your veterinarian may have specific diet recommendations if your pet has a health condition (including arthritis, weight management problems, allergies, and/or gastrointestinal disorders). These recommendations can be complicated to understand, and you might worry will be expensive.
To tackle such a mammoth topic as pet food, let’s start with the ‘easiest’ scenario. Your pet has a health condition and your vet has recommended a Veterinary Prescription Diet. What the heck does that mean? Can you find a food at the pet store that meets your pet’s health requirements?
These were the exact (and justified) questions of owners in a recent case of ours. “Eve” the beagle was in for her annual appointment. She is a beagle with a history of elevated triglycerides (fatty acids) in her blood. She comes by this honestly as it is not uncommon for her breed. However, it does put her at higher risk for ‘pancreatitis’, a potentially life-threatening medical condition often requiring extended hospitalized care.
One of the most effective ways to keep triglycerides reduced in the bloodstream is through a low-fat diet. Thus, Dr. Herberts recommended the Veterinary Prescription Diet Hills ‘I/D Low-Fat Gastrointestinal Restore’. Eve’s owners did their homework and came back with an over-the-counter food that appears to have similar low-fat levels, which we’ll call Food X. Dr. Herberts offered to compare the two diets; she did not have a problem with Eve on a commercial dog food brand that offers the same low-fat content and therapeutic benefits as a Prescription Diet. However, Dr. Herberts had yet to come across one. It takes a large amount of research and feeding trial work to manufacture diets appropriate for specific medical conditions.
Let’s look at what she found:
The Technical Part: To compare any two diets, we have to compare the non-water nutrient content. This is called converting from an “as fed basis” to a “dry matter basis”.
Prescription foods already have the ‘dry matter’ exact nutrient content written on the bag. Hills I/D Low-Fat reports 7.4% crude fat dry matter content in each bag of food.
Commercial diets (aka over-the-counter or pet store brand diets) typically do not test and guarantee each bag to have a precise amount of nutrient content. Instead of reporting ‘dry matter’ analysis, they report something called ‘guaranteed analysis’. This includes minimum percentages for crude protein and crude fat and maximum percentages for crude fiber and moisture. These percentages generally indicate the “worst case” levels for these nutrients in the food and do not reflect the exact or typical amounts of these nutrients.
To compare the fat content of Hills I/D Low Fat with Food X, Dr. Herberts converted the guaranteed analysis to dry matter (effectively comparing all nutrients without their moisture component).
Food X stated a guaranteed analysis of a minimum of 8.0% crude fat, and a maximum moisture content of 8.0%
The Math Part: 100%-8% (moisture) = 92% (dry matter) for Food X. Then we take 8.0% crude fat divided by 92% dry matter = 0.086 X 100% = 8.6% crude fat dry matter.
The Bottom Line: Food X has a MINUMUM of 8.6% crude fat dry matter per bag, whereas the Hills I/D Low-Fat guarantees 7.4% crude fat dry matter in each and every bag.
You might be thinking that the difference between 8.6% and 7.4% is not huge, however within that small word ‘minimum’ lays the danger.
For a dog at risk for a life-threatening condition if they get even a small variability in fat content, Dr. Herberts did not think it worth the risk to chance a commercial brand which could have 8.6% fat in one bag, but closer to 15% or more in the next (for example). Veterinarians use Prescription Diets like medications for specific health conditions. A doctor would not prescribe a medication for a condition if it came with the disclaimer: “contains a minimum of X milligrams of active ingredient”. If a doctor is prescribing a medication, they dose to the milligram, and they expect every pill to be exactly the same. Veterinarians require no less from a diet prescribed for a specific medical condition.
There are other reasons that veterinarians advise Prescription Diets beyond the precise formulation of each bag, but we will save these for another blog entry!
So with regard to Prescription Diets, what’s in the name? The take home message is that although pet store diets may seem similar in nutrient content to a recommended Prescription Diet, you must 1) do some math to make an accurate comparison (this is especially true if comparing canned versus dry food) and 2) recognize the limitations of a food analysis system based on ‘minimums’ and ‘maximums’. These limitations could cost you and your pet additional medical care and medication costs if that over-the-counter diet fails to manage your pet’s health condition, be it an acute spike in triglycerides triggering pancreatitis or failure to slow a chronic condition like kidney disease.
As for diet expense, ask your veterinarian to calculate monthly costs for your pet on their recommended Prescription Diet versus an over-the-counter diet. Depending on the diet, you might be surprised at the result. Prescription diets use less filler and higher quality ingredients to create high digestibility, requiring less volume to meet the same caloric need. This equates to less monthly food volume, and less cost. Some Prescription Diets may be slightly pricier than your ideal pet food budget, however you must weigh these monthly feeding costs against the risk of hospitalization or monthly medication costs if your pet’s health condition is exacerbated by an inappropriate diet. For example, two days of hospitalization for a pancreatitis episode for Eve would likely cost $1500 or more.
As a side-note, sometimes there are second options to Prescription Diets. For example, Eve could also benefit from a balanced homemade diet. This would have to be constructed by her veterinarian in conjunction with a nutritionist, but it is another option.
This is all well and good, but what if your pet currently has no pressing medical condition? Your vet likely has still made recommendations for a certain type of food, be it for joint health, dental health, or even weight management, but how are you to decipher what constitutes a suitable, safe food that meets those suggestions?
To answer this question, stay tuned for Part II of our Safe Pet Food Series!