What you see isn’t always what you get: The potential for undeclared ingredients in pet food

As a Veterinary Nutrition Specialist, one of the more common reasons pet owners would seek out my help was to manage suspected or proven food allergies. In my last post I explained the definition for some ingredients that can be used in commercial dog and cat foods, but when it comes to knowing what is actually in that bag or can you may still be guessing. A recent scientific study on undeclared ingredients in commonly available pet foods pointed out that pet owners may be getting more that they wanted in certain over-the-counter (OTC) foods and treats.

The prevalence (that’s statistics-speak for the number of cases identified each year) for true food allergies in dogs and cats is unknown, but veterinarians and caregivers alike are often quick to blame a food allergy when presented with a dog or cat with itchy skin or diarrhea. Sometimes these cases are a true allergy (i.e., a food protein interacts with an immune cell and causes an exaggerated response), while others are the results of inadequate essential fatty acids (skin problems) or poor digestibility of a food +/- a lack of dietary fiber (diarrhea). The only proven way to diagnose a food allergy is with a dietary elimination and challenge trial. This involves making a list of every food protein (plant and animal) that has ever been fed to the patient; finding a diet (commercially- or home-prepared) that does not include those ingredients; feeding that limited ingredient diet exclusively for 8-10 weeks to see resolution of signs (8-10 week is for skin disease, gastrointestinal signs usually clear up much sooner); and then challenging the patient with either the previously fed diet or individual proteins (plant or animal) and watching for recurrence of sign. One of my own dogs, Raider, had an allergy to beef and was a great example to me of what could happen with re-exposure to an offending protein. I knew that within 12 hours of eating even a single piece of drop hamburger (the reality of life with young kids and dogs) his ears would flare-up bright red and he would start to scratch them almost nonstop. Sometimes this would progress to an overt ear infection and other times it would go away on its own after a day or two. Avoidance was the key to management of his allergies.

People with food allergies on the other hand can develop life-threatening and potentially fatal anaphylaxis when exposed to an offending food protein and because of this on January 1, 2006, the Food Allergen Labeling and Consumer Protection Act (FALCPA) went into effect in the US. This required human food manufacturers to list not only the ingredients they intentionally added to a particular food or supplement, but any potential cross-contamination of outside ingredients that could occur during the manufacturing process. This is why you see labels that look ridiculously obvious like this…

egg warning

I should hope that “egg” is included!

But also ones with potentially hidden allergens like this…

allergy warning

That is a whole lot of foods other than “rice” to worry about.

Which brings me back to the study out of Chapman University on undeclared ingredients in pet foods. There are two ways that unlisted ingredient can find their way you’re your pet’s food:

  • #1: The less sinister explanation is that this is simply a side-effect of the manufacturing process. The reality of pet food manufacturing is that one production line will process a number of different foods, potentially for different companies and brands on the same day. These manufacturing facilities do not close down and clean out the equipment between runs of different foods. A cleaning and sterilization process happens at the end of the production day and it would be too expensive, both from the cost of labor and lost production, to do it after every single food or treat run. Which means that if a “lamb and rice” diet follows a “chicken and rice” diet during processing, little bits of residual chicken will end up in the “lamb and rice” food. Additionally, if any powdered protein ingredients (i.e., “meals”) are in the recipe, small amounts of these powders can end up on the equipment. Think about what happens when you bake at home. I don’t know about you, but as careful as I try to be, I always end up with at least a little bit of flour on the counter (and me!). Cross-contamination of ingredients is a very common occurrence in OTC pet foods and treats and is one of the reasons why limited ingredient diets sold exclusively through veterinarians are more expensive. These prescription-only therapeutic diets are made in a way that prevents cross-contamination of other protein sources so that you as the caregiver know exactly what you are feeding.
  • #2: The second reason undeclared ingredients may find their way into your dog or cat’s food is the more nefarious route, intentional (and illegal) substitution of ingredients. This means that the manufacture or raw material provider may have decided to use “Poultry” (a potential combination of chicken and turkey) as a less expensive alternative to individual “Chicken” or “Turkey”; “Chicken” as a less expensive alternative to “Beef”; or “Meat” (a potential combination of beef, pork, lamb, and goat) as a less expensive alternative to individual “Beef”, “Lamb”, or “Venison”. I’m not saying that this happened with any of the foods tested in this study nor that it happens at all in pet food manufacturing, but if I’m being completely cynical I think it would be fairly easy to pass off one non-descript animal protein ingredient for another. “Poultry meal” (a yellowish-tan powder) looks a lot like “turkey meal” (another yellowish-tan powder); “meat” (reddish-brown muscle protein) can look a lot like “venison”, “beef”, or “lamb” (all reddish-brown muscle proteins). When I look at the details of the DNA results in this article I noticed that a few diets that listed “Turkey” as an ingredient also tested positive for chicken and vice-versa; a few with “Beef” as an ingredient also tested positive for pork, lamb, and/or goat; and one that listed “Venison” was found to have no venison at all. Some of these may have been unintentional cross-contamination that occurred during manufacturing, while others (like the absence of venison in a diet that listed venison) may have been a purposeful substitutions. Irrespective of whether these were intentional or not, this study highlighted some of potential gaps in quality control of the OTC pet food supply chain.

For caregivers who are living with dogs and cats with food allergy, having undeclared proteins can lead to unnecessary discomfort and pain for the dog or cat as well as unnecessary medication and visits to the vet’s office. Allergen warning labels are not required on foods and treats for dogs and cats, so if you want to know what is potentially in your dog or cat’s OTC food, you need to look at every single product that particular brand sells and mentally add them to the List of Ingredients. The veterinary therapeutic diets are easier to figure out; what’s on the List is what’s in the food. Every pet food company big or small is trying to make a profit, the challenge is figuring out which ones are also trying to improve dog and cat health and which ones are solely trying to claim a piece of the $20 billion a year prize.

Happy Feeding!

Lisa P. Weeth, DVM, MRCVS, DACVN

A Sum of Its Parts: Understanding Pet Food Labels, Part 2 of 2.

So what exactly is in that pet food you are feeding?

Words and phrases found in the List of Ingredients (like “corn gluten meal” or “poultry by-product”) have very specific definitions within the pet food industry, but can seem vague and confusing for anyone on the outside. And many alternative pet food companies and self-appointed pet food “advice” websites will use misinformation and fear-mongering to promote their foods or philosophies. My hope is that by providing the actual legal definitions of pet food ingredients, it will help dog and cat caregivers (owners and veterinarians alike) make the best decisions they can when it comes to selecting a food for their beloved companion.

mybowl image

What’s in your bowl? Hint: it doesn’t actually look like that.

The word used for ingredient names in dog and cat foods are determined by laws adopted by individual states as recommended by the Association of American Feed Control Officials (AAFCO) Model Bill and Guidelines. AAFCO was founded in 1909 to help guide what was at the time a fledgling feed industry. Unfortunately (at least in my opinion), as pet ownership evolved over the last 105 years, the rules and regulations on pet food labels and ingredients haven’t quite kept up. The ingredient definitions that the pet food industry has to work with today are a relic of a time when most pet owners didn’t read any food labels, let alone quibbled about what exactly was in “meat by-product”.

Without further ado I will give you what I consider the not-so-secret ingredient definitions from the 2014 AAFCO Official Publication …

  1. Meat and Meat By-Product = From Regulation PF5; Ingredients (b): “The ingredients “meat” and “meat by-product” shall be qualified to designate the animal from which the meat and meat by-product is derived unless the meat and meat by-product are made from cattle, swine, sheep, goats, or any combination thereof.”
  • Translation:  “Meat” cannot be dog, cat, horse, road kill, etc, unless specifically named as such. If it isn’t beef, pork, sheep (lamb/mutton), or goat it cannot legally be included as “meat” or as a “meat by-product”.
  1. Meat = From Official Names and Definitions of Feed Ingredients; Item 9.2: “Meat is the clean flesh derived from slaughtered animals and is limited to that part of the striated muscle which is skeletal or that which is found in the tongue, in the diaphragm, in the heart, or in the esophagus; with or without accompanying and overlying fat and the portions of skin, sinew, nerve, and blood vessels which normally accompany flesh. It shall be suitable for use in animal foods. If it bears a name descriptive of its kind, it must correspond thereto. (Adopted 1938, Amended 1939, 1963).”
  • Translation = It is the muscle and similar type animal proteins from any combination of cattle, swine, sheep and goats (if labeled as “meat”) or the muscle protein from a specifically named food animal  that hasn’t made its way into the human food supply chain. Not because these meats are unfit for human consumption, but because people in the US are squeamish about eating them (mmm, tongue…) or they are not economically feasible to sell as a human food.
  1. Meat By-Product = From Official Names and Definitions of Feed Ingredients; Item 9.3: “Meat by product is the non-rendered, clean parts, other than meat, derived from slaughtered mammals. It includes, but is not limited to, lungs, spleen, kidneys, brain, livers, blood, bones, partially defatted low temperature fatty tissue, and stomach and intestines, freed of their contents. It does not include hair, horns, teeth and hoofs. It shall be suitable for use in animal food. If it bears name descriptive of its kind, it must correspond thereto. (Proposed 1973, Adopted 1974, Amended 1978)”
  • Translation:  “Meat By-Product” is the edible, non-muscle meat protein portions of cattle, swine, sheep, goats, or “any combination thereof” that is not eaten widely by people in the US. It specifically excluded intestinal “contents” (i.e., poop) as well as the non-digestible parts on the animal. The internal organs like liver and kidney are typically what ends up in pet food and are the primary component of “by-product”, but these vitamin and mineral rich foods would otherwise go to waste in the US (we don’t eat much liver and onions now days…). It can technically include brain, but because of BSE concerns, brain is not a common component of “by-product”.
  1. Poultry = From Official Names and Definitions of Feed Ingredients. Item 9.57: “Poultry is the clean combination of flesh and skin with or without accompanying bones, derived from parts of whole carcasses of poultry or a combination thereof, exclusive of feathers, heads, feet or entrails. It shall be suitable for use in animal food. If it bears a name descriptive of its kind, it must correspond thereto. If the bone has been removed, the process may also be so designated by use of appropriate feed term. (Proposed 1978, Adopted 1979, Amended 1995, Amended 1997).”
  • Translation:  Poultry can technically be any bird species used in food animal production such as chicken, duck, turkey, quail, ostrich, or emu, although the reality is that it is almost always chicken, duck and turkey (with or without bone) that haven’t made their way into the human food supply chain. This is not because these poultry proteins are unfit for human consumption, but because people in the US only want to eat breast, leg/thigh, and wing meats and the rest of the frame needs to go somewhere. It is also important to note that bone is allowed unless the Pet Food Company specifically tells you so on the List of Ingredients.
  1. Poultry By-Product = From Official Names and Definitions of Feed Ingredients; Item 9.12: “Poultry By-Product must consist of non-rendered clean parts of carcasses of slaughtered poultry such as heads, feet, viscera, free from fecal contents and foreign matter except in such trace amounts as might occur unavoidably in good manufacturing practice. If the product bears a name descriptive of its kind, the name must correspond thereto. (Proposed 1963, Adopted 1964, Amended 2000).”
  • Translation:  It is everything except the frame meat from a chicken, duck, and/or turkey, but specifically not poop (“fecal contents”).  Yes, it can include heads and feet, but the reality is that poultry producers will usually get a higher price for heads and feet on the “ethnic” food market for human consumption (mmm, chicken feet…) than they will from the Pet Food Companies.  The internal organs are typically what end up in pet food and are the primary component of “by-product”, but again these vitamin and mineral rich foods would otherwise go to waste in the US.
  1. Poultry By-Product Meal = From Official Names and Definitions of Feed Ingredients. Item 9.10: “Poultry By-Product Meal consist of ground, rendered, clean parts of carcasses of slaughtered poultry such as necks, feet, undeveloped eggs, and intestines, exclusive of feathers, except in such amounts as might occur in good manufacturing practices. …[guaranteed amounts of specific nutrient are listed next, but I’ve left them out here]… If the product bears a name descriptive of its kind, the name must correspond thereto. (Proposed 1985, Adopted 1990, Amended 2000).”
  • Translation:  I don’t know why there are two different lists of what can be included in fresh vs. processed “poultry by-products”, but there are and there are some key differences between the two. The biggest being that chicken poop (“fecal contents”) is specifically excluded from fresh “poultry by-products”, but feathers are what is excluded “poultry by-product meal”. So if you follow the letter of the law, “poultry by-product meal” can include poultry feces, while “poultry by-product” can include feathers, but not vice-versa. Weird distinction, but now you know.
  1. Rendering = From Official Feed Terms: “cooking and separating process in which conditions such as time and temperature, with or without pressure, are sufficient to remove water, kill pathogenic microorganisms, and separate fats and oils from other components.”
  • Translation:  Meals are the dehydrated, defatted product of cooking an ingredient prior to incorporation into pet foods. Depending on the source protein, “meals” can be good ingredients or bad. Using animal protein “meals” allows for a very specific and consistent amount of protein in the diet without the worries of water or fat fluctuations that can affect formulation using fresh meats (of any kind), but the rendering process can alter the structure of essential amino acids making them less digestible and create a nutrient deficiency if not corrected by the manufacturer.
  1. Adulteration , Model Bill and Regulation
    1. Section 7 (a) (7): “If it consists whole or in part of any filthy, putrid, or decomposed substance, or if it is otherwise unfit for feed”
    2. Section 7 (a)(9): “If it is, in whole or in part, the product of a diseased animals or of an animal that has died otherwise than by slaughter”
  • Translation:  Only healthy food animals and non-disease parts can be included in pet foods, anything else is considered an “adulterant” and subject to legal action against the manufacturer or raw material provider. The truth about the types of animal proteins that can legally be added to pet foods is not nearly as exciting and head-line grabbing as telling pet owners that “4D” meats go into main stream pet food (4D=dead, dying, diseased and disabled if you haven’t heard this term before).
  1. Gluten = From Official Feed Terms: “The tough, viscid nitrogenous substance remaining when the flour of wheat or other grain is washed to remove the starch.”
  • Translation:  Gluten is just the generic term for protein from grains. People who have “gluten” sensitivities or Celiac Disease  are actually reacting to the proteins gliadin and glutenin that are specific to wheat, rye, and barley (grains in the wheat family); these are not found in corn or rice at all, so “corn gluten” or “rice gluten” can be eat by people  with documented “gluten” problems.
  1. Brewers Rice = From Official Names and Definitions of Feed Ingredients. Item 75.4: “Chipped Rice, Broken Rice, or Brewers Rice is the small fragments of rice kernels that habe been separated from the larger kernels of milled rice.”
  • Translation:  The less aesthetically pleasing pieces of rice that don’t end up in people foods. I love that the other synonymous terms are “broken” or “chipped” rice. I can understand why Pet Food Companies prefer the term “Brewers Rice” instead.
dog-food-label-9 - Copy

But real lamb is the first ingredient!

As a Veterinary Nutrition Specialist the only times I run into problems with some of these ingredients is when I encounter a dog or cat with food allergies or with liver dysfunction.  For animals with suspected food allergies previous diets that included “meat” and/or “poultry” on the List of Ingredients could potentially contain any combination of beef, pork, lamb, goat, chicken, duck and turkey, so I need to avoid all of them in the new diet; “Poultry By-Product Meal” can also include eggs, so now I have to add that to the list of foods to avoid, too. Animals with liver disease should not be fed diets with any “By-Products” since feeding organ meats (especially liver!) may worsen their clinical signs and increase the risk of developing hepatic encephalopathy or urate bladder crystals/stones. And the only times I worry about “Gluten” is if has been contaminated with melamine and cyanuric acid, which shouldn’t happen now that Pet Food Companies are testing for these potential contaminants, or if I have an animal with a suspected food allergy to that particular plant protein.

So why do some Pet Food Companies continue to use these vague, often misinterpreted ingredient names? My theory is that these terms were originally adopted into the AAFCO guidelines (1938 for the oldest, 1985 for the newest) at a time when pet owners wanted to buy the lowest cost food for their dogs and cats and the specific ingredients had little to no importance as long as the food was safe and healthful. BY using these general ingredient terms Pet Food Companies could provide a least-cost food that easily complies with label regulations. If a Pet Food Companies makes a food with “Meat”, “Poultry” or “By-Product” then they have what would I would considered an “open formulation” and are legally allowed to substitute nutritionally comparable ingredients depending on cost and ingredient availability, without having to submit new product approval to the FDA first.  If a Pet Food Company lists specific animal ingredients (like “Beef” or “Chicken”) then they have what I consider a “closed formulation” and any substitution to a specifically name ingredient list would be considered an “adulteration” and would be illegal unless they obtain prior approval, a process that can take months to years. These two methods of developing a pet food formulation are equally nutritious. “Open formulation” are easier and less expensive from a production standpoint, but are a pain when trying to find a novel diet to manage a suspected food allergy.

The take-home message…

Every ingredient used in a pet food is a “by-product” of the human food supply chain. If it wasn’t, only the very wealthy would be able to feed their pets (or themselves!) and we would have an even larger problem with food waste than we already do. Personally, I don’t have a problem with pet food manufacturers using the clean, edible parts of plants and animals that people would otherwise discarded, this is the ultimate in eco-friendly, sustainable feeding practices. I just wish you could walk down the pet food aisle without needing to consult the AAFCO Office Publication to understand the ingredient list!

Happy Feeding!

Lisa P. Weeth, DVM, MRCVS, DACVN

What’s in a Name? Understanding pet food labels, part 1 of 2

All pet foods sold within the United States are required by law to have certain key pieces of information on the label. Adherence to these requirements are regulated both at the Federal level (enforced by the Food and Drug Administration [FDA]) and at the State level (enforced by State Feed Officials).  The FDA requirements are fairly minimalistic. All animal “feeds” (dog and cat food falls under this category) must have: 1) a way of identifying the product (name or product number); 2) a net quantity (gram amount); 3) a name and address (city or street) of manufacturer or distributor; and 4) a list of ingredients written in common industry terms (note: this doesn’t mean that anyone else needs to understand them).  Most of the individual 50 states have also adopted guidelines proposed by the Association of American Feed Control Officials (AAFCO). AAFCO has no regulatory enforcement and they cannot make states adopt all or even part of what they call the “Model Bill and Regulations”, but if any Pet Food Company wants to sell across multiple states, they will usually meet the most stringent of the state labeling laws. In addition to the 4 FDA pet food label requirements, you should also find: 5) a species designation (it has to say whether it is intended for a dog, a cat, or both); 6) a guaranteed analysis; 7) feeding guidelines; 8) nutritional adequacy statement; and 9) a calorie statement.  It seems like a lot of information to take in, but once you know what is required by law vs. what is added for fluffy marketing you will be able to evaluate the merits of each food better.

dog at bowl

What’s in your food?

So here is your list of label requirements and explanations of each…

  1. Product Name

All pet foods must have a formal name that distinguishes it from other foods within the same brand. The way the Product Name is written will also tell you about the formulation of the food.

The hidden “code” in Product Names:

The 95% Rule: If the Product Name is written as “Chicken for Cats” or “Beef for Dogs” then at least 95% of the weight of the food (not counting water added for processing) must be that named ingredient, AND must be at least 70% of the finished product (so with the water added).

The 25% Rule: Also called the “Dinner” rule. If a food is listed as a “Chicken Dinner” or “Turkey & Sweet Potato Dinner”, then at least 25% (not including water added for processing) must be the named ingredients, AND must be at least 10% of the finished product, AND the ingredients need to be listed in descending order of weight (so for the turkey and sweet potato example, there needs to be more turkey than sweet potato), AND none of the named ingredients can be less than 3% of the total.

The 3% Rule: Also called the “with” rule. Examples of this would include Product Names like “Beef Dog Food with Cheese” or “Cat Food with Chicken”.  Any ingredient that follows the word “with” in the Product Name must be at least 3% of the total finish product.

Flavors: When it says, for example, “chicken flavor” the actual named ingredient isn’t required as long as the dog or cat thinks it tastes like it anyway. Maybe this is why everything tastes like chicken…

Also it is important to know that ingredients other than those listed in the Product Name can still be included in the formulation and you should always check the label if you are trying to avoid certain proteins (plant or animal) that may trigger a reaction in your dog or cat. More on ingredient definitions in my next entry.

  1. Net Quantity

Pretty self-explanatory. This tells you how much is in the bag or can of food. If there is no net weight on the packaging, stop. Put it back on the shelf and move on.

  1. Name and Address

This is where Pet Food Companies that use third-party manufacturers can get a bit tricky. The requirement by the FDA and supported by AAFCO is for a name and address of the party taking responsibility for the food, not who actually made it. When you look for the Pet Food Company contact look to see whether the food was “Manufactured by…”, “Distributed by…”, or “Manufactured for…” the Pet Food Company printing their name on the label.

“Manufactured by…”

Pet Food Manufacturing Companies are up front with who makes their foods. These pet foods will either list their own company name or the name of the parent company of the brand label (this is usually the case for pet foods manufactured and distributed by the larger multinationals, for example Alpo is made by Nestle Purina and Nature’s Variety is made by Big Heart Brand, which was Del Monte Foods until they changed the name of the pet care business in February 2014). Pet Food Manufacturing Companies will own all parts of manufacturing and distribution (and often some of the ingredient supply chain) so that they can control product quality more tightly (I’m sure it helps reduce production costs, too).

“Distributed by…” or “Manufactured for…”

Pet Food Marketing Companies on the other hand either lack the financial capital to build a pet food manufacturing facility, or they have decided to skip the sciencey-stuff and instead spend money on print ads, tv/web commercials, and making the cutest darn label graphics you ever did see. Either way, Pet Food Marketing Companies contract production of their food, add their own label to the finished product, and then sell it. Often at a “premium” price. This is a pretty common occurrence in the pet food industry and it can be nearly impossible to know who makes what for which company because of confidentiality agreements between all parties. There are a few marketing companies that I consider to be of a better caliber than others. These are the companies that out-source manufacturing, but still enforce quality control standards for raw materials and finished products by having independent testing done. They may be small companies but are genuinely trying to make a pet food that improves animal health and performance whether it is for a couch kitty, or a sled dog.  Unfortunately there are many more Pet Food Marketing Companies that skip along intentionally ignorant of what is actually in their finish products. They are too busy counting their money and thinking up ways to dupe owners into spending more for pet food to worry about silly details like bacterial contamination or whether their food actually has the right nutrient balance.

As for the address, a street (i.e. snail-mail) address is not required as long as the company is “listed in either a city directory or a telephone directory”. Do those still exist in the US? Now days, almost all Pet Food Companies websites and a quick Internet search will lead you to a link for contact resources. If contact information is missing on your food or treat package, put it back. Do not feed it. If the company doesn’t know enough to comply with federal and state laws I wouldn’t trust them to make a safe food.

  1. List of Ingredients

The only requirements for the List of Ingredients are that it is ordered by weight and is written in industry accepted terms. Ah, how simple that sounds, but contentious it can be.  In my next post I am planning to cover ingredient definitions, but for now I will tell you that that every Pet Food Company is guilty of padding their labels to make certain ingredients move up or down on the ingredient list. To make an animal protein jump up higher on the list, they simply use one animal protein and many different types of carbohydrates (like a diet that includes chicken, barley, oat, amaranth, potato, sweet potato, quinoa, carrots,…) or they use “meals” (i.e., dehydrated, defatted protein powders) of other animal proteins so that you can honestly say “Chicken is the #1 Ingredient!” (as a wet weight) on their packaging even when the next two ingredients are poultry meal and poultry by-product meal and make up a larger proportion of the total dietary protein than the fresh chicken meat.

mybowl image

Probably not exactly what is in the food, but you get the idea.

  1. Species Designation

Another pretty easy one to understand. Dog food has to be listed as “dog food” and cat food has to be listed as “cat food”. If there is no indicator on which one you should feed it to, stop. Put it back on the shelf and move on.

  1. Guaranteed Analysis

Only four things are required to be included on the Guaranteed Analysis (or “As-Fed Basis”): Crude Protein (listed as a minimum), Crude Fat (listed as a minimum), Crude Fiber (listed as a maximum) and Moisture (listed as a maximum). Pet Food Companies will often list other things to highlight nutrients that they think will encourage pet owners to buy their food. This is the Pet Food Companies way of saying, “look at me! look at me! I care about your dog because I include (fill in the blank)!”. They all do it. My concern with the Guaranteed Analysis is that many dog and cat caregivers will use this as a reference for comparison between brands of foods, but these values are only estimates and tell you nothing about the quality of the food or the nutritional values.

The terms “crude” refer to the method of testing use to estimate protein, fat and fiber levels in the product. Crude Protein for example is estimated by measuring the absolute nitrogen content of the food, which is then used to back calculate to a specific amount of actual protein. This is where pet food manufacturers got into trouble in 2007. At that time raw material providers took rice and wheat flours (low nitrogen containing benign powdered ingredients) and added melamine and cyanuric acid (two high nitrogen toxic industrial chemicals). This was done to make these flours look like the higher nitrogen containing ingredients rice gluten and wheat gluten (“gluten” is simply the name for a plant protein).  The recipients of these contaminated flours only tested for nitrogen levels at that time, and since they matched what was expected for rice gluten and wheat gluten, they were added to foods. It wasn’t until children in Asia and pets in the United States (any elsewhere) started going into kidney failure and dying that the intentional contamination was found. No one had thought to test for melamine and cyanuric acid in food ingredients before April of 2007, but everyone does now.

If I could change one thing about pet food labels it would be to do away with the Guaranteed Analysis completely and replace it with something more representative of what is actually in the food. Minimum values tell you the lower limit for protein and fat, but for animals with specific needs or intolerances to higher levels of these nutrients, the potential maximum values are more problematic. Animal proteins are expensive so the Proximate Analysis (actual amounts in each batch that are monitored internally by Pet Food Manufacturers) and the Guaranteed Analysis values (listed on the label) for Crude Protein are often the same, but fat is cheap and especially in foods with higher amount of fresh animal proteins (like canned cat and dog foods), fat content can be highly variable. Proximate Analysis for Crude Fat can be up to 25-30% higher than the Crude Fat number listed on the label, and is allowed as normal variation in raw materials. This may surprise pet owners since Pet Food Companies like to use images of lean meats on their label graphics (like chicken breast or beef loin), but what you need to know is that animal proteins used by Pet Food Companies are the fatty cuts that people in the US don’t want to eat. For the most part, the meats used in all pet foods are the “by-products” of the human food supply.  It will still be fresh, high-quality, USDA- inspected chicken that is used, it is just the back and wing meat, not the breast. Unless the manufacturer has tight control on nutrient specifics for ingredient, there can be quite a bit of variation in fat levels in canned foods. See my last entry on Poop if you want to learn more about what happened when you inadvertently increase your dog’s fat intake.  Dry foods have a more constant fat level batch-to-batch. Because dry foods are exposed to air after opened, any increase in fat level in a dry pet food will require an increase in the amount of preservatives used to prevent the food from going rancid.

And the last problem with the Guaranteed Analysis is that you also can only compare food that have similar moisture (i.e., water), fiber, and mineral (“Ash”) contents. Some people will advocate factoring out the water and convert everything to a “Dry Matter Basis” for comparison, which doesn’t really work for today’s foods. Forty years ago when all dry foods were basically the same ingredients in different packages, it may have worked. But today’s pet foods can have dramatically different fiber levels and different mineral levels, each of which will have a dilutional effect on the other numbers. For example, Company X can use a poor quality protein (which has a high Ash content) in their food, but add very little fiber. Company Y on the other hand may use a good quality protein (which has a lower Ash content), but also have added fiber for gastrointestinal health. The result would be that the Crude Protein number on the label for Company X’s food may be higher than or Company Y, even though Company Y’s diet may a better quality food.  The other problem with converting everything to a “Dry Matter Basis” is that it requires the use of a calculator and knowledge of conversions. I consider myself a math nerd and there are a lot of simple calculations I can do in my head, but dividing the crude protein value by the dry matter content and then multiplying by 100 while standing in a pet food aisle is not one of them.

  1. Feeding Guidelines

Every one complains about Feeding Guidelines, even people who work in the pet food industry, and they are almost always wrong for the “average” pet. But, Feeding Guidelines are required to be on pet food labels by most State Feed laws so we’re stuck with them. Knowing a few key pieces of information will help make them more user-friendly though. First thing to understand is that they are calculated from one of 2 different math formulas that can be used to estimate energy requirements for dogs and cats. These formulas were developed over 50 years ago on dogs and cats living in research setting (so minimal activity and minimal breed variation). The second thing to know is that even within those populations from 50+ years ago, individual variation was +/- 50%. In my experience calculated energy requirements very rarely match actual needs of dogs and cats living in home environment. I collected food intake information on every dog and cat I saw for the last 12+ years and compared it with the calculated energy “requirement” (yep, math and nutrition nerd) and they rarely matched. For example, the “average” 40 lb mixed breed dog has calculated requirement of either 986 Calories per day or 1182 Calories per day (depending on the formula used) and then when you factor in normal variation for physical activity and medical health you have a potential daily Calorie range of 493 to 1773(!). Pet Food Companies can’t possibly give guidelines that will work for every animal, but they can give us a place to start.  Even better yet would be for every dog and cat owner to keep track of how much your dog or cat needs to eat to maintain an ideal body condition. Then you can make your own feeding guideline based on Calories per cup or can that are provided on the package. The most important aspect of feeding (other than making sure the diet is balanced) is to keep your canine or feline companion at an optimal weight for their size, irrespective of actual amount fed.

  1. Nutrition Adequacy Statement

This is another part of the label that I use to evaluate the quality of a Pet Food Company itself. Every pet food requires a statement that the food is either “complete or balanced…” for a given life-stage (growth, adult maintenance, or both) or is intended for “for supplemental or intermittent feeding”. Food intended to support normal healthy animals is labels as “complete and balanced” and things like treats are “intermittent feeding only”. So if you are feeding your dog only dog cookies each day, you may want to check the label.  Certain therapeutic diets, like ones developed for animals with kidney disease, may also be labeled as “intermittent feeding only” and are ok to use longer-term when needed but should only be fed under veterinarian supervision.

Pet Food Companies have two ways of gaining a “complete and balanced” Adequacy Statement. One way is to generate a formula for a diet on a computer, make sure it meets the established mins and maxs for essential nutrients according to AAFCO recommendations, make the food, and then sell it. This is a diet that has been “formulated to meet the needs”. The other way a “complete and balanced” Adequacy Statement can be written is that it has gone through “feeding trials”. A diet that has undergone feeding trials also starts with a computer generated formula, making sure that it meets the established mins and maxs for essential nutrients according to AAFCO recommendation. The food is then made and feed it to a group of test subjects in a controlled environment to ensure nutritional adequacy before being sold for feeding to other dogs and cats.

AAFCO Feeding Trials have strict minimum standards. The diet used in the trial must come from the same batch of food (to minimize batch-to-batch variation that can occur and may influence blood work values); it must be fed exclusively (so no treats or substitutions allowed); it must have a minimum number of animals (only 8, which is not a huge number, but will still tell you if the food has any major concerns); must be fed for a designated period of time (6 months for a maintenance trial); and all animals must meets basic physical exam and blood work parameters for heath during the time of the trial. Feeding Trials are not mandatory in order to sell a pet food and the minimum requirements for an AAFCO Feeding Trial are not considered the “gold standard” for optimal nutrition by any legitimate Pet Food Company, but a Feeding Trial will give the company an idea of whether there are any larger issues with their assumed “complete and balanced” formulations. Every dog and cat food sold in the US started as a diet that was “formulated to meet the needs”, but certain problems (like nutrient interactions) won’t show up on a computer screen, but would be hard to miss in a Feeding Trial.


  1. Calorie Statement

The American College of Veterinary Nutrition (ACVN) has helped advise AAFCO for years and in 2005 ACVN began petitioning to have a Calorie Statement added to the label requirements; finally in 2011 it gained approval and in 2012 having a Calorie Statement was officially added to the AAFCO Model Bill and Guidelines. Your ACVN in action!

What can you take home from this?

Today’s pet food labels aren’t perfect,  but there is a good bit of information on what I consider “company quality” that you can find when you start reading labels with an educated eye.  Does the company make their own food? If they don’t will they tell you who does? Are they monitoring quality of their products? Or simply making money at the expense of dog and cat health?  Everyone thinks that their food is the best, but I tend to have a preference for companies that are willing to spend a little bit of money to prove it. If you want to read more about pet foods and label regulations check out websites for AAFCO and the FDA.

Happy Feeding!

Lisa P. Weeth, DVM, MRCVS, DACVN

Let Talk About Poop

Poop. Everybody does it, and dog and cat owners are almost universally fixated on the quality and frequency of their animal’s defecation habits. Is it too soft, too hard, too smelly, too frequent, in the wrong place? I think just about every consult I had in my referral practice was either about poop, or poop would get worked into the discussion somehow. For some of my patients it was diarrhea that brought them to my exam room, but even in those with “healthy” gastrointestinal tracts, occasional soft stool or diarrhea, especially after a diet change or overindulgence (usually the unintended stealing-food-off-the-counter kind), would occur.

everyone poops

A must read for everyone with human kids.

Pet owners are aware of their dog or cat’s defecation habits more so than their own, and definitely more so than their other human family members (unless you are the caregiver of a kids still in diapers). My kids are well passed potty-training and as a parent of pre-teen kids I’d be hard pressed to tell what their poop is like day-to-day unless my son forgets to flush the toilet (he is a boy after all). My cats, though, are a different story.  I know that the youngest one, Loki (1), gets diarrhea if he eats too much canned cat food or with certain brands of dry cat food, but he can eat small amounts of people foods without ill effect; the oldest one, Oliver (17), gets colitis if he eats the wrong variety of canned food but seems to do well with just about any dry foods; and my middle cat, Cosette (3), has an iron stomach and has had perfect poops since we brought her home as a kitten no matter the diet. And yes, I can identify each of their poops in the litter boxes and know that Cosette and Loki like to poop in one box and pee in another, but that anything goes with the third box. I also know that the old man of the bunch has pretty bad arthritis and long hair so he occasionally gets hangers-on because he stands instead of squats now. TMI with the litter box habits, but if other pet owners can share with me I should be able to share with you, too.

So what causes diarrhea and how can you as a caregiver decrease the risk that you will be cleaning it up off laundry room floor? The first thing to understand is roughly how the gastrointestinal tract works. The basic idea is that the process of digestion begins in the stomach with acid and enzymes breaking down proteins. Food exits the stomach into the upper small intestine in a controlled fashion to help prevent overwhelming small intestine’s absorptive capacity (the small intestine can handle only so much food at a time). In the upper small intestine (the duodenum), the pancreas releases bicarbonate to neutralize the acid and additional enzymes to continue the protein breakdown as well as start digestion of fats and carbohydrates. The gall bladder also releases bile into the duodenum at the same time to allow fat to be absorbed. These smaller particles are then absorbed along the length of the rest of the small intestinal (primarily the jejunum, but also the ileum to some extent). A dysfunction of any one of these organs will prevent normal absorption and can cause diarrhea (with a different appearance and more severe health consequence compared to diet-induced colitis), but so can feeding a larger volume of food or a larger amount of protein, fat, or carbohydrates than what the body is equipped to handle at that time. Diarrhea caused by making an abrupt diet change will often get better over 3-4 days, about how long it takes for the pancreas, liver (where bile is made), and  small intestine to catch up, but sometimes needs medical from your Veterinarian help to clear up faster.

Once the nutrients have been absorbed in the small intestine, whatever is left makes its way to the large intestine (colon) were it is formed into what we recognize in the litter box and yard as normal poop. The colon acts as a “holding tank” until the appropriate time and place to move the poop out; water and nutrients that are dissolved in water can be absorbed from the colon; and the colon is home to a large number of bacteria, many of which support animal health and normal colon function. These beneficial bacteria can release essential vitamins from the remaining foodstuff (like vitamin K), can produce compounds that support colon cell health (such as butyrate, the preferred energy of the colon cells), and can outcompete pathogenic bacteria such as Salmonella and Campylobacter preventing them from getting a foothold and causing disease. The beneficial colonic bacteria prefer to use dietary plant fibers (fermentable fibers specifically) as a food source, but will use protein, fat and starches if necessary. Some of the most noxious gasses produced in the colon (such as cadaverine, the smell of rotting flesh that some gassy dogs can make) are created by the bacterial fermentation of undigested animal proteins. Non-fermentable, insoluble fibers (like bran or cellulose) are necessary as well, adding bunk and form to the poop and acting as “nature’s broom” sweeping out sloughed intestinal cell and extra bacteria.  Changes in diet, especially changes in protein, fat and fiber levels, can cause a bacterial dysbiosis (meaning the amount and types of bacteria in the colon get out of whack) and are a common cause of diarrhea in dogs and cats.

Oliver in his younger poopy bottom days.

Oliver in his younger poopy bottom days.

In my experience, inadequate fiber intake in otherwise healthy dogs is a relatively common cause of colitis-like signs especially if they are a large breed or when they are fed certain commercial diets. Boxers, German Shepherd Dogs, and Labrador Retrievers are just a few of the breeds that tend to do better with extra fiber in their diet (both fermentable and non-fermentable types). They are the ones I think of as being at a higher risk for colitis when fed some of the so-called “premium” diets. Unless the food is being made by a company knowledgeable about animal health and nutrition it will often have low fiber, high fat and high protein levels; the perfect storm to create a bacterial imbalance.

My fiber and pet food soapbox: Most of the “premium” priced foods are actually distributed by marketing companies with little to no understanding of animal nutrition. Their motivation is to sell food at a “premium” price. (As an aside, the term “premium” within the pet food industry actually indicates the price point, not the quality of food; owners just assume it is a nutritional value statement as well and none of these companies are going to correct them.) These “premium” priced foods companies have been telling pet owners  that fiber is a “filler” and that higher fiber ingredients like corn and wheat are “bad” ingredients used by “cheap” dog foods. This pet food myth has also been perpetuated by pet food “advice” sources who are parroting the marketers and giving these benign foods almost supernatural powers to cause all sorts of ills. Yes, the US grows a lot of corn and wheat so the cost of these ingredients is relatively low compared to other grains like barley or amaranth and, yes, lower cost pet foods tend to have higher proportions of corn and wheat (and rice but that is a low fiber food so I’m ignoring it for now) since these grains are also less expensive than animal protein.  That doesn’t make corn and wheat “bad” foods to include in pet foods, just common and less expensive ones, and these “premium” priced food would loath to be considered common.

Porkchop and corn

Taffy and one of her favorite foods, freshly killed corn!


Fiber is also not considered an essential nutrient for survival for dogs, cat, or people (meaning you won’t die if fiber is left out of your diet, but you’ll sure feel like it) and there is no legal requirement for it to be added to pet food. Very high levels of dietary fiber can interfere with nutrient absorption and an over reliance on cereal grains is not an optimally balance diet either. Too much fiber can increase the volume of stool, making your Yorkie poop like a Labrador. It can also interfere with absorption of essential fatty acids and essential minerals required for optimal skin and coat health, so dogs and cats on high fiber diets that are not balanced correctly can start to look pretty shabby.

Big, well-formed poops, and a dry hair coat won’t cause you to make a midnight trip to the Emergency Vet, but chronic low fiber intake may. Dogs not getting enough dietary fiber are the ones that seem to get diarrhea out of the blue and are acting normal otherwise. Metronidazole (Flagyl) usually clears things up within a day, but then anywhere from 1 to 3 months later these dogs get diarrhea again. Usually at 2 AM on a Sunday morning. Cats being carnivores are adapted to a lower fiber diet so inadequate fiber intake is not much of a problem in otherwise healthy cats. But even cats can develop diarrhea from too quick of a diet change or from increases in fermentable fibers intake that upset the bacteria balance (things like guar gum, pectin, inulin, and carrageenan are all fermentable fibers that can be used in canned cat foods). Colitis in cats makes a mess in the little box and is not fun for anyone, especially if you have a long-haired cat like mine, who would leave little poo-poo butt prints wherever he went.


Tips to keep your pet regular:

  1. Don’t change diets abruptly, unless this is already your routine. If your cat or dog is used to eating a new type of food with varied levels of protein, fat and fiber each day (like your own diet) then you are probably ok to continue rotating foods. But if you are like the vast majority of pet owners who buy the same bag of kibble each time, any change in food (even if it is more expensive) will cause a few days of diarrhea. This is not your pet “purging” the “bad” food out (one of my favorite marketing gimmicks to rationalize a food causing diarrhea), this is just normal physiology. Usually it will clear up in a few days, but occasionally requires a course of metronidazole to get the bacteria back in balance. To avoid this, gradually transition between different foods over 5-7 days.


  1. Know how much fiber in your dog or cat’s current food. The pet food label will indicate Crude Fiber (which is mostly the non-fermentable, bulking-type fiber), but a quick check of the ingredient list will tell you if there are fiber containing ingredients or supplements added. Whole grains of any kind will have a higher fermentable and insoluble dietary fiber content. Potatoes and sweet potatoes are high in fermentable fibers, but low insoluble fiber (so bacteria growth without the bulk to push them out). Higher protein diets (dry or canned) will typically have low fiber levels as well.


  1. Add fiber if needed. If your dog or cat is eating a low fiber food and everything is working well, then don’t change a thing, other than following Tip #1. But, if you have a standing order of metronidazole at your local pharmacy or veterinary clinic, then you may want to consider either changing to a diet with more fiber or adding fiber to the current diet. I have a busy family schedule so personally like to simplify meal times and would just change the diet, but not everyone can do this. If your dog or cat is on special diets for medical reasons (like food allergies or kidney disease) then you should check with your Veterinarian to find out if there is a higher fiber option available. Some therapeutic diets will have a lower Calorie version, which is the same base diet with fiber added. For other dogs and cats you may be able to add a fiber supplement or higher fiber food (that is compatible with the feeding plan) to the existing diet.


Examples of Fiber Supplements and Dietary Fiber Amounts:

Canned pumpkin: Relatively low fiber, but dogs (and some cats) like the flavor so I will often use this to hide other fiber supplements.  One 1/4 cup of canned pumpkin provides 20 Calories and 2 grams of total dietary fiber (1 fermentable, 1 non-fermentable/insoluble).

Ground Psyllium: More concentrated fiber supplement. Ground psyllium becomes gelatinous when wet and can increase frequency of defecation in some dogs, which will mimic signs of colitis, so be careful with the amount. Depending on the brand used, 1 level teaspoon can provide 10 Calories and 3 grams of total dietary fiber (2 fermentable, 1 non-fermentable/insoluble).

Oat Bran: Used as a fiber supplement, but with different fiber distribution than psyllium. Depending on the brand used, 1 rounded teaspoon provides 5 Calories and 3 grams of total dietary fiber (1 fermentable, 2 non-fermentable/insoluble).

Inulin: Used as a fiber supplement, but with different fiber distribution than psyllium or oat bran. Depending on the brand used, 1 rounded tablespoon provides 5 Calories and 3 grams of total dietary fiber (3 fermentable, no non-fermentable/insoluble).


Just like most nutrients there is not a one-size-fits-all fiber intake for every dog or cat, but hopefully I have given you some insight into how you can keep your dog or cat looking and feeling good for years to come.

Happy Feeding!

Lisa P. Weeth, DVM, DACVN