Digestibility Matters

In  “Dog Food Logic” and “Only Have Eyes for You“, I have emphasized (okay, some might say “harped upon”) the need for pet food companies to provide digestibility information to consumers. It is not a difficult value to determine and most pet food companies already conduct feeding trials that measure this (yet keep the results to themselves). As one of the most basic measures of food quality, digestibility provides essential information that can help dog owners to select the best food for their dog.

What is digestibility (and why does it matter)? To refresh, digestibility reflects a food’s ability to deliver essential nutrients to the dog who is eating it. This ultimately affects not only defecation quantity and quality (how much your dog poops and how the poop looks and smells), and a dog’s propensity for flatulence (no explanation needed), but more importantly, a dog’s longterm health and wellness. This graphic, presented in the essay, “Scoopin’ for Science“, summarizes how digestibility is measured using feeding trials with dogs.

Digest Trials

In case you have not noticed, it is that last step, “Provide Results to Consumers” that is glaringly absent from the dog food scene. But, I harp (again).

Onward. There is good news to tell.

Good vs. Poor Digestibility: The term digestibility coefficient refers to the percent of a food that the dog absorbs into his or her body during the process of digestion. As a rule of thumb, dry dog foods with digestibility values of 75 % or less will be of very poor quality, those with values between 75 and 82 % are classified as moderate in quality, and foods with digestibility values that are higher than 82 % are of high quality. If you see products with 88 % or more reported digestibility, you have a rock star.  (For a more detailed explanation of dog food digestibility, see “Dog Food Logic“).

The paradox lies in the fact that while many pet food companies routinely measure the digestibility of their products, they are not required to report this information to the people who buy their foods. Most do not provide this information even when it is directly requested. Digestibility matters (a lot), but we cannot judge foods with information that we do not have.

The good news is that two research studies measuring the digestibility of dog foods formulated with different types of protein sources were recently published by a group of animal nutritionists from the Norwegian University of Life Sciences and the University of Copenhagen in Denmark (1,2). The first compared the digestibility of dog foods that used three common animal protein meals and the second compared the use of fresh chicken meat (aka “chicken first”) with poultry meal as protein sources in a dry food. Because all of the protein ingredients that the researchers examined are frequently found in commercial foods, their results may be helpful to you in your search for a quality food.

Like me, you may be surprised by what they found:

Lamb, fish, or poultry meal? In the first study, the investigators compared the protein and overall digestibility of three dry (extruded) dog foods that were formulated containing equivalent amounts of either lamb meal, fish meal or poultry meal (1). Because one of the objectives of their work was to determine if mink provide a suitable model for assessing pet food quality, they tested the foods in growing mink, adult mink and adult dogs.

Results: As a protein source, lamb meal showed significantly lower values for multiple measures of protein quality and essential amino acid content when compared with both poultry meal and fish meal. Even though all three diets were formulated to provide complete and balanced nutrition, the lamb meal diet was found to be deficient in the essential amino acid methionine, when digestibility was taken into account. Although differences between poultry and fish meals were not as dramatic, poultry meal was of lower quality than fish meal. As a protein source in dog food, fish meal had the highest values on almost all quality measures, including digestibility and essential amino acid content. When tested in adult dogs, the protein digestibility values of the three foods were 71.5, 80.2, and 87.0 for lamb meal, poultry meal and fish meal, respectively. Overall, this study suggests that, at least for the sources used in this work, the order of protein quality was lamb meal (poor), poultry meal (moderate), and fish meal (high). Additionally, although the reported level of lamb meal in the diet exceeded the minimum methionine requirement for adult dogs, the actual amount of methionine that was available to the dogs (i.e. was digested) was less than their minimum requirement for this nutrient.

lamb-meal-vs-poultry-vs-fish

LAMB MEAL IS SIGNIFICANTLY LOWER IN DIGESTIBILITY THAN POULTRY MEAL AND FISH MEAL WHEN INCLUDED IN AN EXTRUDED DRY DOG FOOD

Is fresh chicken better? The team’s second study is groundbreaking. It is the first to examine whether or not there is a demonstrated benefit to including “fresh” (frozen, actually) chicken in an extruded, dry dog food. This is important because the promotion of “fresh first” on pet food labels is frequently used as a claim for higher protein quality in the product. The researchers tested the digestibility and amino acid content of fresh, raw chicken (technically referred to as “raw mechanically separated chicken meat”) before processing (cooking) and then again after it was included in a dry dog food to replace about 25 percent of the product’s poultry meal. Because raw meat has been shown to be more digestible than dry rendered protein meals, it was hypothesized that including raw chicken in the dry food would indeed improve the foods digestibility by several percentage points. (Note: Because mink had been previously shown to be a suitable model for dogs, adult mink were used to test the diets).

Results:  As expected, when tested before processing the digestibility of raw chicken meat was significantly higher than that of rendered poultry meal (88.2 % vs. 80.9 %, respectively). However, when the raw chicken meat replaced 25 percent of the poultry meal in an extruded dry food, the digestibility of the food was not significantly improved  (81.3 vs. 80.3, respectively).  In addition, the digestibility of several essential amino acids was actually higher in the food containing only poultry meal than in the food that included the raw chicken meat.

chicken-not-better-than-poultry-meal

WHEN INCLUDED IN A DOG FOOD, FRESH (RAW) CHICKEN MEAT DOES NOT IMPROVE THE FOOD’S PROTEIN DIGESTIBILITY OR AMINO ACID AVAILABILITY COMPARED WITH POULTRY MEAL

Take Away for Dog Folks

Wow. The results of these two studies contradict several previously accepted (if never actually proven) dog food edicts. These are:

  1. Lamb meal is a high quality protein source for pet foods. Um, apparently not. The first study found that lamb meal was poorly digested (70.5 %) and provided inadequate levels of an essential amino acid, methionine after digestibility was taken into account.
  2. Named species meals are always superior to generic meals. This refers to the general rule of thumb that dog folks should always choose a food that uses chicken, turkey, salmon or lamb meals over the less specific meat, poultry or fish meals. At least regarding the animal-based protein sources used in these studies, choosing lamb over the generic poultry or fish may not get you the quality you are hoping for.
  3. Chicken first on the pet food label means higher quality (more digestible) protein: Nope again. While the digestibility of fresh chicken meat was higher than that of poultry meal when tested prior to processing, incorporating fresh chicken (as 25 percent of the protein source!) into an extruded food did not improve digestibility or lead to a higher quality product. The researchers speculated that this may have occurred because raw meat ingredients could be more susceptible to damage caused by the heating and drying processes of extrusion than are rendered protein meals. Regardless of the cause, it appears that “Chicken First’ may not be the marketing holy grail that pet food companies are promoting it to be.
soapbox

UP ON MY SOAP BOX

This is great information for dog folks to have. Many thanks to this team of researchers, among others (all notably at universities, not from pet food companies) who have been publishing scientific evidence regarding the protein quality, amino acid content, digestibility and safety of various dog food ingredients and products. We are grateful to you all and hope to see more of these types of studies. Although these do not (yet) go so far as to provide us answers to the most important question: “What is the digestibility of the  brand of food that I am feeding to my dog?” they provide needed and essential information.

I have said this many times before and will say it again:

If pet food manufacturers insist on telling us that their brands of food are expected to provide “complete and balanced nutrition” throughout our dogs’ lives, then providing a few very simple measures of the quality of those foods is not too much to ask.

The researchers of these papers agree. They finish the abstract of their first paper with this statement: “Furthermore, the study showed that to ensure nutritional adequacy of dog food and to be able to compare protein quality of dog foods, information of AA [amino acid] composition and digestibility is crucial“. [Emphasis mine].

So, pet food manufacturers……..are you listening? Time to step up and provide this information on your labels, websites, or at the very least, in response to direct inquiries.  In the meantime, I will continue to report and promote research studies that provide us with the information that we need to choose smart for our dogs.

Until next time, happy feeding and happy training!

Chip and His Cake

CHIPPY WONDERS ABOUT THE DIGESTIBILITY VALUES OF HIS CAKE

Cited Studies:

  1. Tjernsbekk MT, Tauson AH, Matthiesen Cf, Ahlostrom O. Protein and amino acid bioavailability of extruded dog food with protein meals of different quality using growing mink (Neovison vison) as a model. Journal of Animal Science 2016; 94:3796-3804.
  2. Tjernsbekk MT, TAuson AH, Kraugerus OF, Ahlstrom O. Raw, mechanically separated chicken meat and salmon protein hydrolysate as protein sources in extruded dog food: Effect on protein and amino acid digestibility. Animal Physiology and Animal Nutrition 2017 (in press).

 

Happy New Year from The Science Dog! (The 2017 Pet Blogger Challenge)

Happy New Year from The Science Dog!

To start the year off, I am participating for the first time in The Pet Blogger Challenge that is organized by the travel site, Go Pet Friendly. Many thanks to my friend Eileen Anderson for alerting me to this annual event. Below are this year’s queries and my responses. I hope you enjoy learning a bit more about The Science Dog!

  1. When did you start your blog and, for anyone who is just seeing it for first time, please provide a description of your site. Would you say your blog focuses more on sharing stories with your readers, or providing a resource for your audience? Answer: I created The Science Dog in September of 2013, shortly before the publication of my fifth book, “Dog Food Logic“. The purpose of The Science Dog is to provide up-to-date, evidence-based information to dog folks and pet professionals about dog training, behavior and nutrition. My focus is primarily on original scientific research that has been published in peer-reviewed journals. I try to find studies whose results are relevant to trainers and dog owners and then summarize these in what I hope is a “user-friendly” style. Oh, and yeah, sometimes I editorialize a bit.

    soapbox

    GETTIN’ UP ON THE OL’ BOX

  2. What was your proudest blogging moment of 2016? Answer: I published the second Science Dog book in July of 2016, entitled “Only Have Eyes for You“. Both writing and promoting it has been a lot of fun! My husband Mike designed the cover for the book (as he did for “Beware the Straw Man“), and I was especially tickled that he used a photo of four of our dogs, posed in our garden. The oldest girl, Cadie, has since passed away, so this photo is very near and dear to my heart.

    Cadie Chip Vinny Cooper May 2013

    CHIPPY, VINNY, CADIE AND COOPER

  3. Which of your blog posts was your favorite this year and why? (Please include a link.) Answer: I enjoyed writing all of the posts, especially the nutrition essays, as I had focused the first two years of the blog on topics related to behavior and training. In 2015, I started to include more essays about nutrition and feeding practices. However, my personal favorite of 2016 has to be “The Perfect Dog“, because it reviews two recent papers that provide some insight into the gap between what people think a dog should be versus who dogs actually are (and also, to some degree, places the responsibility for this exactly where it lies).       Unrealistic Expectations
  4. Year after year, one goal that we all seem to share is that we want to reach more people. What one tool did you use or action did you take this year that had the most impact on increasing traffic to your blog? Answer: I use FaceBook quite a bit, and have a FB Science Dog page that gives dog folks access to the blog and allows readers to chat and to contact me directly. I love to hear from readers, especially when they have ideas for new science-based topics for the blog! (hint-hint).
  5. Which of your blog posts got the most traffic this year? (Please include a link.) Have you noticed any themes across your most popular posts? Answer: The essay that received the largest number of hits (~ 18,000) was “When Sit Doesn’t Mean S*it“. Catchy  little title aside, I think that it resonated with shelter professionals because it presents a set of research studies conducted by Alexandra Protopopova’s team that both challenged a prevailing belief about training and adoption rates and presented some unique solutions that may be more effective as predictors of dogs’ chances for adoption.   Sit Ubu
  6. What blog do you find most inspirational and how has it influenced your blog? (Please include a link.) Answer: There are a number of dog-related blogs that I follow regularly and enjoy. Two that are among the best are Eileen Anderson’s not-to-be-missed essays about dog training at EileenandDogs and Julie Hecht’s excellent research summaries at Dog Spies.
  7. What is one thing your readers don’t know about you or your pets that would surprise them? Answer: What my readers may not know (but all of my friends do) is that while I hold a Masters Degree in Canine/Feline Nutrition, I cannot cook a human food meal to save my life. I started volunteering two years ago at our local soup kitchen, The Daily Bread, and the other volunteers quickly learned this little secret. I am now a designated dish-washer and happily report that I excel at that particular task, keeping everyone safe (and well fed).

    daily-bread-people-2

    SUPPORT YOUR LOCAL SOUP KITCHEN! 

  8. What is something you’ve learned this year that could help other bloggers? Answer: Not to point any political fingers (interpret this as you like), but my advice to other writers (and citizens) is: Don’t lie and stick to the facts that have evidence to support them.    just-the-facts-maam-2
  9. What would you like to accomplish on your blog in 2017? Answer: The biggest challenge that I may have in 2017 is finding enough time to work on all of the writing and dog training projects that I am excited about. I am currently writing a new dog training book that presents evidence-based training and the applications that we use at our training school, AutumnGold, plus developing a few new training courses with several of AutumnGold’s instructors and writing essays for The Science Dog (many of which will appear, in some form, in the new book). Add in training and enjoying time with my own dogs, and it looks like it will be a busy and fun year!

    Cooper and Alice Standing Platforms

    PLATFORM TRAINING AT AUTUMNGOLD!

  10. Now it’s your turn! You have the attention of the pet blogging community – is there a question you’d like answered, or an aspect of your blog that you’d like input on? Answer: Thanks to GoPetFriendly for sponsoring this blog challenge and hop! This is a Blog Hop!

“Only Have Eyes for You: Exploring Canine Research with The Science Dog” – Kindle Edition Now Available!

The Kindle edition of Only Have Eyes for You: Exploring Canine Research with The Science Dog” is now available! Click on the image below for more information and to order.

Book description:  In her second Science Dog book, Linda Case tackles commonly held beliefs about canine nutrition, pet foods, behavior, social cognition and training. Each of the book’s 32 chapters explores a current issue that is of interest to dog owners and pet professionals and presents the scientific evidence that supports or refutes commonly held claims and beliefs. Learn about pet food ingredients and research showing that what is on the label may not always be in the food, about measures of food quality (and what consumers may not know about the foods that they buy), and about the safety and digestibility of popular dog treats and chews. Other chapters review new information regarding how dogs communicate, factors that help or inhibit a dog’s ability to learn, and the effectiveness of different types of training. Find out if dogs are capable of “knowing what someone else knows”, if they feel empathy for their friends, if they bark for no reason, and if they are capable of feeling guilt following a misdeed. Learn more about breed stereotyping, factors that influence our perceptions of dogs, and which canine characteristics most influence our attraction to particular dogs. This newest Science Dog book has something for everyone who works with and trains dogs, as well as for those who simply love dogs and enjoy learning more about our canine best friends.

                                                                             ♥♥♥♥♥♥♥♥♥♥♥♥♥♥

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New Book! “Only Have Eyes for You: Exploring Canine Research with The Science Dog”

Only Have Eyes for You: Exploring Canine Research with The Science Dog” (paperback version) is now available! Click on the image below for more information and to order. (Kindle version will be available soon!)

Book description:  In her second Science Dog book, Linda Case tackles commonly held beliefs about canine nutrition, pet foods, behavior, social cognition and training. Each of the book’s 32 chapters explores a current issue that is of interest to dog owners and pet professionals and presents the scientific evidence that supports or refutes commonly held claims and beliefs. Learn about pet food ingredients and research showing that what is on the label may not always be in the food, about measures of food quality (and what consumers may not know about the foods that they buy), and about the safety and digestibility of popular dog treats and chews. Other chapters review new information regarding how dogs communicate, factors that help or inhibit a dog’s ability to learn, and the effectiveness of different types of training. Find out if dogs are capable of “knowing what someone else knows”, if they feel empathy for their friends, if they bark for no reason, and if they are capable of feeling guilt following a misdeed. Learn more about breed stereotyping, factors that influence our perceptions of dogs, and which canine characteristics most influence our attraction to particular dogs. This newest Science Dog book has something for everyone who works with and trains dogs, as well as for those who simply love dogs and enjoy learning more about our canine best friends.

                                                                             ♥♥♥♥♥♥♥♥♥♥♥♥♥♥

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I Bow for Your Play

At AutumnGold we have an informal group of trainers and dog friends who get together regularly to do a bit of dog training, go for group walks, and give our dogs free time to play. During play time, we take care that the dogs who are loose together know one another well, are  comfortable together and demonstrate good play manners. We include plenty of “calling out of play” and play pauses to keep things safe and tension free. One of the most enjoyable things about these sessions is that they give us a chance to watch our dogs having fun together and to observe the many ways in which dogs communicate during play.

And there are certainly a lot of ways.

Play 1Play 2

Play 4  Play 5

While many of us learn a great deal from watching our dogs play, there is also a substantial body of science on this topic. Researchers have long been interested in the expression and functions of animal play in a variety of species. Specific studies of play in dogs are not as numerous, but several scientists, such as Marc Bekoff, Nicola Rooney, John Bradshaw and Alexandra Horowitz have published work that examines play behavior in young and adult dogs.

Most recently, a team of researchers at the University of Michigan focused their work on a very specific component of canine play (1).

Play Bow 2

THE PLAY BOW

The play bow is a common and highly stereotyped play signal in dogs (and several other canid species as well). However, the precise meaning of this posture is not completely understood. Marc Bekoff’s earlier work with puppies and young adults suggested that dogs tend to bow prior to making a move that might be misconstrued by their play partner, such as feigning a bite or attack, as a way to clarify playful intent (2). In other words, the play bow is analogous to a dog saying “Hey, dude. Just wanted to remind you that this is all play. I just mention this because the next thing that I plan to do is well…..bite your ear. Remember this is all play, ‘kay?” Other possible functions of play bows are as visual signals to reinitiate play after one or both of the play partners have paused, as strategic moves that allow a dog to position himself ready to either pounce upon or dodge his play partner, or, because play bows are often offered simultaneously, as a way to synchronise play behavior.

Play Bow 1

PLAY SYNCHRONIZATION?

The Study: Because it is quite possible that play bows are highly flexible signals and may have multiple functions, the researchers searched for evidence for all of the aforementioned possibilities. They presented four hypotheses regarding the function of the play bow: to clarify play intentions, to reinitiate play after a pause, to position oneself for escape or attack, or to synchronize play behaviors. They also studied the role of the play bow as a distinctly visual signal, which if true, would mean that play bows are only offered when a dog is within the visual field of his or her play partner.

The team analyzed a set of videotaped play sessions of 16 dogs playing as pairs. The dogs were playing in large enclosed backyards or a public area. All of the dogs were well socialized, played well together, and varied in their degree of familiarity with one another. Some had just recently met while others were well-acquainted friends. Play behaviors were coded according to a previously developed ethogram of adult dog behavior and were independently recorded by three reviewers. The number of play bows, their context, and each dog’s behavior before, during and after play bows were recorded. Results: A total of 414 play bows occurred during 22 separate play sessions. Four play pairs were responsible for the majority of the play bows (76 %). By comparison, no other pair accounted for more than 5 percent of total bows, suggesting that play bows vary dramatically among individuals and play pairs. There was no indication of an influence of age, sex or size influencing the number or form of play bows. However, this may be due to the relatively small sample size and are factors that could be examined in future work.

The collected data suggested the following regarding the function of play bowing for adult dogs during play:

  • Both bowing dogs and their partners showed an increase in active play behavior following a play bow, supporting the hypothesis that play bows function to reinitiate play following a pause.
  • The type of behaviors that dogs showed prior to and immediately following play bows tended to be similar within pairs, suggesting that play bows also help play partners to synchronize behavior. These results are corroborated by another recent study showing that dogs who use play bow mimicry tend to play together longer than those who do not (3).
  • More than 98 percent, virtually all, of the play bows occurred when the two dogs were within each others’ visual fields, providing strong support for the hypothesis that play bowing is an intentional visual signal that dogs only use when they know that their partner can see them and respond.
  • Although the researchers did not find support for Bekoff’s theory of  the play bow as an intention clarifying signal, they note that his work was primarily with puppies and young dogs, and used a different methodology. It is possible that the bow serves this function for young dogs while they are initially learning to play and to inhibit their bite, but is less necessary for adult dogs.
  •  Of the 16 dogs in this study, a single individual, a Belgian Tervuren named Tex, played with five different dogs and was responsible for more than 40 percent of the total play bows counted in the study. In contrast, several dogs showed just one play bow in a session or did not bow at all.

Take Away for Dog Folks

For dog folks, play bows are a welcome sight during paired or group play among adult dogs because we seem to intuitively grasp their use as a non-threatening and friendly signal. This new research, coupled with the earlier work of Marc Bekoff, suggests that bowing during play is not a random event that is just part of play, but rather that it is used to communicate specific information. For adults, this seems to be an invitation to continue play –  “Hey pal, let’s start playing again!” – as well as perhaps a way to coordinate and synchronize movement “Okay Charlie, let’s bow together and when I say GO, you shall zig and I shall zag”. And for young dogs and perhaps some adults, it may also serve to clarify playful intent.

An additional important piece of information from this work is that play bows may be highly individual. Just a few pairs in the study used multiple bows and a single dog, Tex, apparently was bowing all over the place. I bet many of you are nodding right now. Because anecdotally, many of us have seen this in our own dogs or in dogs we work with. In the play group at my school, Colbie, a young Pit Bull, is a champion play-bower. She offers not only multiple play bows during paired and group play sessions, but she offers them at record speed, seemingly as an invitation to chase. My five-year-old Golden, Cooper, also bows during play, but (again anecdotal here), he seems to bow most frequently when he plays with dogs who he knows well such as his housemates, and is less likely to play bow during group play.

Coop Ally Colbie Play

PLAY TIME FOR COOPER, ALLY AND COLBIE

Ally, on the other hand, prefers to chase and to be chased.

Colbie and Ally Chase

Ally and Colbie Chasing

Like all good research, this new study stimulates thought and additional questions to ask about the play bow. For example, what factors might influence a dog’s frequent use of the bow – is it age, personality traits such as level of confidence or degree of playfulness, degree of familiarity among the dogs? Are there possibly learned components, such as training the play bow on cue? Does the use of a play bow ever “end badly”? In other words, do some dogs misinterpret this ubiquitous signal?

Lots to learn, and I am looking forward to seeing more from this team of researchers. Until then, play on, dogs, play on.

100225T114

CHIPPY’S PLAY BOW IS TRAINED – DOES THIS AFFECT HIS SPONTANEOUS PLAY BEHAVIOR?

Cited Studies:

  1. Byosiere SE, Espinosa J, Smuts B. Investigating the function of play bows in adult pet dogs (Canis lupus familiaris). Behavioural Processes 2016; 125:106-113.
  2. Bekoff M.Play signals as punctuation: The structure of social play in canids. Behaviour 1995; 132:5-6.
  3. Palagi E, Nicotra V, Cordoni G. Rapid mimicry and emotional contagion in domestic dogs. Royal Society of Open Science 2:150505; http://dx.doi.org/10.1098/rsos/150505.

Excerpted from: “Only Have Eyes for Your: Exploring Canine Research with the Science Dog” (2016).

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What’s in Your (Vegetarian) Food?

Here we go again.

It appears that there may be more than what dog owners expect to find in vegetarian dog food.

Hold the Spam, Please: Before all of the  “Dogs are Carnivores (and a pox on your mother if you think differently)” devotees begin posting comments (in all caps ) that dogs should NOT be fed a vegetarian diet in the first place, let me state that this is not what this blog piece is about. So please, don’t even start. The point of this essay is not to argue (again…..) whether or not dogs have an absolute requirement for meat in their diet (here’s a hint: They don’t). Rather, today we examine new information about undeclared ingredients that may be present in dog food and the mounting evidence of regulatory violations within the pet food industry.

In this newest pair of studies, a team of veterinary nutritionists at the University of California tested vegetarian pet foods for label compliance and ingredient content.  I have written about this before, and unfortunately once again, the news isn’t good.

25-Foods-That-Seem-Vegetarian-But-Arent

Label Compliance: In the first study, the researchers collected samples of 24 dog and cat food brands that carried a label claim of “vegetarian” (1). The majority of the foods were over-the-counter products purchased at a local pet supply store. Three products were veterinary therapeutic diets. Of the group of products, 19 were formulated for dogs or for dogs and cats, and five were formulated exclusively for cats.  Product labels were examined for their compliance with the Association of American Feed Control Official (AAFCO) model regulations, which are the basis for most state mandated pet food regulations. Pet food samples were also analyzed for total protein and essential amino acid content. Results: Of the 24 foods, only eight (33 %) were in complete compliance with AAFCO label regulations. This means that 16 brands (66 %) had one or more violations. The most common infractions were the omission of feeding instructions or caloric content, improperly reported guaranteed analysis panels, and mislabeled ingredient statements. Nutrient analysis showed that all but one of the foods met AAFCO’s minimum crude protein requirements. However, six brands had deficient levels of one or more of the essential amino acids. This means that while the total amount of protein that the food contained appeared to be sufficient, essential amino acid requirements, which are more important, were not always met.

Presence of Animal-Based Ingredients: In a second study, the same group of researchers tested 14 brands of vegetarian pet foods (2). They purchased each food on two occasions to obtain samples as duplicates from different manufacturing batches. Six were dry and eight were canned products. Samples were analyzed for the presence of mammalian DNA using an accepted laboratory technique called multiplex polymerase chain reaction (PCR). Since all 24 foods were marketed as vegetarian (and in some cases, as vegan), none included animal-based components in their list of ingredients. Results: All six of the dry (extruded) foods that were tested contained DNA from beef, pork or sheep and five of the six contained DNA from multiple animal species. These results were consistent across batches for all 7 products.  Only one of the 8 canned vegetarian foods contained animal DNA (beef) and this finding was not repeated in the second sample. In this study, the researchers also tested for the DNA of dogs, cats, goats, deer, horses, rats, mice and rabbits. DNA from these species was not detected in any of the samples. Similar to earlier studies that have found the DNA of undeclared meats in dog foods, the amount of animal-based ingredients in the foods could not be quantified. The researchers could not speculate whether the labeling violations were a result of deliberate adulteration or unintentional cross-contamination of vegetarian products with meat-containing foods produced at the same facility.

soapbox

Soap Box Time: The Federal Food, Drug and Cosmetic Act requires that all pet foods sold in the United States are safe, produced under sanitary conditions, contain no harmful substances, and are truthfully labeled (emphasis mine). Perhaps I am being picky, but labeling a food as vegetarian and then not ensuring that the food indeed lacks the meat of cows, pigs and sheep, seems to qualify as not being truthful. (Some might even call it lying, I suppose). Not only are such egregious errors in violation of both FDA and AAFCO regulations, but they seriously impact the trust that dog owners have in pet food manufacturers. And rightly so.

To date, the majority of pet owners in the US continue to feed dry, extruded food. Of the dry-type vegetarian foods tested in this study, all of them, 100 % were, in fact, not vegetarian at all. This leads one to ponder about other products on the market and whether it is more the norm than the exception for dry dog foods that are sold as vegetarian to be nothing of the sort. While the authors note that this was a small number of products and so do not represent all vegetarian foods, the fact that all of the foods failed their DNA tests is alarming.

What can you do as a dog owner? Contact the manufacturer of your food and ask them how they verify the integrity of their products, specifically, the ingredients that they include in their foods. If they are not forthcoming and transparent with their response, find another producer who is. The good news is that the pressure that research studies such as these place on pet food companies and upon the industry as a whole will hopefully encourage increased transparency and improved regulatory oversight – something that we are apparently in dire need of.

Cited Studies:

  1. Kanakubo K, Fascetti AJ, Larsen JA. Assessment of protein and amino acid concentrations and labeling adequacy of commercial vegetarian diets formulated for dogs and cats. Journal of the American Veterinary Medical Association 2015; 247:385-392.
  2. Kanakubo, K, Fascetti AJ, Larsen JA. Determination of mammalian deoxyribonucleic acid (DNA) in commercial vegetarian and vegan diets for dogs and cats. Animal Physiology and Animal Nutrition 2016;  doi: 10.1111/jpn.12506.

 

Want Flies with that Shake?

Fries with Shake Mod

Well, not actually you, but rather your dog.

Before food purists get up in arms over  this topic, consider that numerous human cultures have historically viewed insects as acceptable and even highly desirable food items. And today, our ever-expanding human population and the increasing need for sustainable sources of food have led to increased consideration of insects as food in almost all human cultures.

Insects for Dinner

So, it’s not much of a jump to ask – what might this mean for feeding dogs?

It’s all about the protein: Protein is the most expensive nutrient in the diet of all animals, including humans. It is expensive both in terms of the monetary cost of its production and its ecological impact upon the environment. In the spirit of sustainability (a buzzword that pet food companies and other corporations love to trot out) and with the goal of reduced production costs (i.e. making foods more cheaply), pet nutritionists at The Nutro Company recently identified a number of potential alternative protein ingredients for dog and cat foods. Bugs, being plentiful, cheap, and protein-replete are included on that list.

And protein is all about amino acids: Although we talk about a dog’s protein requirement and about a food’s protein level or quality, the actual requirement that dogs and all animals have is for the essential amino acids (the building blocks of the dietary protein) and the nitrogen that dietary protein supplies. The reason that the parlance of nutrition centers on dietary protein is simply because foods contain protein, not individual amino acids. It is during the process of digestion that a food’s protein is broken down in the small intestine into its component amino acids, which are then absorbed into the body. So, at the level of an animal’s metabolic needs, it is the amino acids that actually count. This is why one of the first steps that nutritionists take when examining a potential protein-containing ingredient is to examine its amino acid composition.

So, can insect protein supply all of the essential amino acids that dogs require? The nutritionists at Nutro and at the University of California at Davis decided to find out (1).

The Study: A wide variety of different plant, algae and insect species were identified as potential alternative (and sustainable) protein sources for pet foods. Within the group of insects, the researchers focused on the adult and larval forms of various species of flies, cockroaches, and ants.

Cockroach      Ants                    COCKROACHES                                                           ANTS        

 

           Blowfly adult         Blowfly larvae                          FLY (ADULT)                                                     FLY LARVAE

All of the bug samples were analyzed for total protein and amino acid content. (I will spare you the details regarding sample acquisition and preparation in case you are reading this during your lunch hour). Amino acid analysis included measurement of the 10 essential amino acids plus taurine, a special type of amino acid that is found primarily in animal tissues. Many readers are probably familiar with taurine as an essential dietary nutrient for cats. Because there is evidence that taurine may be needed during periods of physiological stress in some dogs, it has recently been classified as a “conditional essential amino acid” for dogs as well. Because sources of taurine are limited, it is an important essential nutrient to measure when considering new ingredients for dog and cat foods.

Results: Larval and adult forms of five different insect species were analysed. Here are their primary findings:

  • High in protein: Total protein levels in all of the insect species were quite high. When reported on a dry matter basis, concentrations ranged between from 46 % in Black Soldier Fly larvae to 96 % in cockroaches. (Cockroaches? Who knew?).
  • Bugs can do it: All but one species of insect (Black Soldier Fly larvae) were found to contain sufficient concentrations of protein, essential amino acids, and taurine to meet or exceed the NRC requirements for growth for dogs and cats. The finding for taurine was rather surprising because it has been previously assumed that rich sources of taurine included only skeletal muscle and organ meats.
  • Ants and flies are best: Two groups of insects, ants and adult flesh flies, contained the most concentrated sources of taurine. However, these initial results suggest that all three of the groups that were studied – ants, cockroaches, and flies – may be nutritionally acceptable protein sources for dog and cat diets.

Take Away for Dog Folks

Dogs and cats (like humans) require nutrients in their diet, not ingredients. Therefore, if a particular protein ingredient can supply most or all of the dog’s essential amino acids, is nutritious when fed, and is safe and palatable, then it technically meets the criteria (ick factor aside) to be considered as a potential dietary ingredient. Having passed the first test of adequate protein and amino acid content, where do insects fall on these other criteria?

  • Nutritious when fed: This refers to how digestible and bioavailable the essential nutrients of the ingredient actually are, when fed to the dog. For example, some insects and plants contain anti-nutritional factors, compounds that interfere with the ability to digest or use certain nutrients. Some of these compounds can be toxic or so potent as to cause illness, making their presence a clear “no-fly zone” for pets (pun intended).
  • Safety: Many species of bugs have ways to protect themselves from becoming someone’s meal. They produce toxins that cause illness or consume plants whose by-products are toxic to animals. They may also just taste really, really nasty. Clearly, toxic bugs are out.
  • Acceptability: Living with four dogs, one of whom is a notorious poop-eater, I would venture that the acceptability issue is as much about the human side of the equation than it is the dog side. Still, dogs must not just accept a bug-flavored food, they must relish it.
Dogs Watching Eating 2

THE BOYS WATCH MIKEY AS HE TRIES THE LARVAE-FLAVORED CHOW

Will owners accept it? Might Cockroach Recipe for Seniors or Fly Formula for Active Dogs be a hard sell? My (gut) instinct is to say yes, especially in the US. We all project our own preferences and desires onto our dogs – it is our nature to do so. This is why dog foods that depict entire roasted chickens and sirloin steaks on their front panels sell so well (however misleading such graphics may actually be).

Still, seeing that there is a booming market for dog foods containing alligator meat, brushtail (Australian Possum), and Unagi (freshwater eel), along with treats made from dried bull penises, pig hooves and cow tracheas, one must admit that the bar is already set pretty low. Will insect dog food be next up?

Cited Study: McCuster S, Buff PR, Yu Z, Fascetti AJ. Amino acid content of selected plant, algae and insect species: A search for alternative protein sources for use in pet foods. Journal of Nutritional Science 2014;3:e39;1-5.