The Heart of the Matter

In mid-July, the U.S. Food and Drug Administration (FDA) released an alert to veterinarians and pet owners regarding reports of increased incidence of a heart disease called canine dilated cardiomyopathy (DCM). This disorder is characterized by weakening of the heart muscle, which leads to a decreased ability of the heart to pump, and if untreated, to cardiac failure. The reported cases occurred in breeds that are not considered to be genetically predisposed to this disorder.

Further, a significant number of the dogs were found to have reduced levels of circulating taurine in their blood and have responded positively to taurine supplementation. It is speculated that these cases are related to the consumption of foods that negatively affect taurine status, leading to taurine-deficiency DCM. Foods containing high levels of peas, lentils, other legume seeds, or potatoes were identified by the FDA as potential risk factors. These ingredients are found commonly in foods that are formulated and promoted as “grain-free.”

As these things go, there followed a lot of hype and a fair bit of hysteria in response. Let us avoid this type of reaction and instead look at the evidence – what do we currently know about the role of diet and taurine in the development of DCM in dogs and how is it that “grain-free” foods have been recently targeted as a possible dietary cause?

What is Taurine? The nutrient taurine is a unique type of amino acid, called a beta-amino sulfonic acid. It is not incorporated into proteins but rather is found primarily as a free amino acid in body tissues and circulating in the blood. Taurine has many functions, but two that are important for this discussion involve its role in normal heart function and its presence as a component of bile acids, which are needed for fat digestion. Most animals obtain adequate taurine to meet their needs by producing it endogenously (in the body) from two other amino acids, methionine and cysteine.

TAURINE

This means that while animals require taurine physiologically, most do not have a dietary requirement for taurine. The exception to this rule is the cat. Cats (but not dogs) always require a source of taurine in their food. If they do not have it, one of the diseases that they can develop (and possibly die from) is……you guessed it…..DCM.

Taurine-deficiency DCM is well documented in cats. We also know quite a lot about the dietary factors that contribute to this disease in that species. In contrast, dogs (usually) do not require a source of dietary taurine. However, we know that some dogs still develop taurine-deficiency DCM. Why does this happen? The history of DCM in cats can help in untangling what may be occurring in dogs.

Taurine-deficiency DCM in Cats: Looking back, I cannot avoid a sense of déjà vu. In the early 1980s veterinarians began reporting increased incidences of DCM in pet cats. By 1987, a role for dietary taurine was suspected. In a seminal study, a veterinary researcher at UC Davis reported low plasma (blood) taurine levels in 21 cats with clinical signs of DCM (1). When the cats were supplemented with taurine, all 21 completely recovered from the disease. This discovery led to a series of controlled studies that supported the existence of taurine-deficiency DCM developing in cats who were fed diets that contained sufficient concentrations of taurine.

What was going on?

It has to do with Bile Acids: Another role of taurine is the body is that it is necessary for normal bile acid function. Taurine is linked to bile acids in the liver to form bile salts. These compounds are secreted into the small intestine during digestion where they function to aid in fat digestion. Animals are very efficient at conserving the taurine that is secreted into the intestine by reabsorbing the bile salts back into the body further down the intestinal tract. This occurs through a process called “enterohepatic reutilization” and prevents a daily loss of taurine in the feces.

Herein lies the problem for cats with DCM: If anything happens during digestion that causes the degradation of the bile salt taurine or that inhibits its reabsorption into the body, more is lost in the feces. If this happens consistently, the cat will experience an increase in his or her daily need for dietary taurine. Simply put – if anything causes the cat to poop out more taurine-bile acid complexes (or their degraded by-products), the cat will be in danger of a taurine deficiency if a higher level is not provided in the diet.

This is exactly what was happening in the cats with taurine-deficiency DCM – and is possibly what we are seeing today in dogs. The difference is that we know what diet factors caused taurine deficiency in cats during the late 1980s. These factors are not yet fully understood for dogs (but we can make a few guesses).

Here is What We Know: The studies with cats found that several dietary factors influenced taurine status (2,3,4). These were the level and type of dietary protein, the amount and type of dietary fiber, and the degree of heat treatment that was used during food processing. These factors could affect taurine status in three ways:

  1. Bile Acid Binding: Certain fibers and peptides (small protein chains) in the food can bind with bile salts the small intestine and make them unavailable for reabsorption into the body. This results in an increased daily loss of taurine in the feces and a subsequent increase in daily taurine requirement to replace that loss.
  2. Increased Microbial Degradation: Thermal processing of protein (extrusion or canning) can lead to the production of Maillard products – complexes of sugars and amino acids and are poorly digested in the small intestine. The undigested complexes travel to the large intestine and provide an intestinal environment that favors increased numbers of taurine-degrading bacteria. An increase in these bacterial populations reduces the proportion of taurine that is available for reabsorption and reuse by the body.
  3. Reduced Taurine Availability: Taurine is found naturally in animal-based proteins but is not found in plant-based protein sources. Therefore, providing diets that include a sufficient level of high-quality animal proteins (that are not heat damaged) should ensure adequate taurine intake. However, protein that is of low quality or that has been excessively heat-treated will be poorly digested, reducing the availability of taurine and of its precursor amino acids, cysteine and methionine. (Note: Cats produce small amounts of taurine from these precursors, while dogs can produce all of their needs from them, if adequate levels are available).

In response to new information regarding the interaction of dietary factors and taurine status in cats (and their relationship to DCM in cats), the Association of American Feed Control Officials (AAFCO) increased the recommendations for dietary taurine in extruded and canned cat foods in the early 1990s. The current recommendations are 1000 mg taurine/kg (0.1 %) in dry (extruded) cat foods and 2000 mg taurine/kg (0.2 %) in canned cat foods.

So, What about Dogs? Unlike the cat, dogs that are fed diets containing adequate levels of protein should be capable of synthesizing enough taurine from the two amino acid precursors, cysteine and methionine, to meet their needs. Therefore, a requirement for dietary taurine has not been generally recognized in dogs.

Breed Predispositions: However, there is evidence – evidence that we have had for at least 15 years – that certain breeds of dogs, and possibly particular lines within breeds, exhibit a high prevalence of taurine-deficiency DCM. Genetically predisposed breeds include the American Cocker Spaniel, Golden Retriever, Labrador Retriever, Saint Bernard, Newfoundland and English Setter (5,6). Although the exact underlying cause is not known, it appears that some breeds have either a naturally occurring higher requirement for taurine or a metabolic abnormality that affects their taurine synthesis or utilization.

Size: A second factor that affects taurine status in dogs is size. There is evidence that a large adult size and a relatively slow metabolic rate influences the rate of taurine production in the body and may subsequently lead to a dietary taurine requirement. It is theorized that increased body size in dogs is associated with an enhanced risk for developing taurine deficiency and that this risk may be exacerbated by a breed-specific genetic predisposition. For example, when compared metabolically, Newfoundlands have a significantly lower rate of taurine synthesis than Beagles (7).

There is additional evidence that large and giant breed dogs have lower rates of taurine production compared with small dogs. Ultimately, studies suggest that certain dogs possess a genetic predisposition to taurine depletion and increased susceptibility to taurine-deficiency DCM and that this susceptibility may be related to the combined factors of breed, size and metabolic rate.

What is the Role of Diet? The recent spate of cases and media attention to taurine-deficiency DCM in dogs suggests that this is a very new problem in dogs. However, it is not new. A connection between diet and DCM in dogs was first described in a paper published in the Journal of the American Veterinary Medical Association in 2001 (8). What is new is the sudden focus on certain pet food ingredients and the target that appears to have been placed upon the backs of all “grain-free” pet food brands by some bloggers and veterinarians. Not to put too fine a point on this, but the 12 cases of taurine-deficiency DCM described in the 2001 paper were collected between 1997 and 2001, years before grain-free dog foods had arrived on the pet food scene. Rather than disparage one class or type of dog food (or pet food company), it is more important to look at specific dietary factors that may be involved in DCM in dogs.

Generally speaking, these are expected to be the same as those identified for cats, including low protein levels, poorly processed or heat-damaged proteins (leading to Maillard products), and the inclusion of a high proportion of plant-based protein sources such as peas and legumes.

Over the past 15 years, reduced taurine status in dogs has also been alternately associated with feeding lamb meal and rice diets, soybean-based diets, rice bran, beet pulp, and high fiber diets (9,10,11). As with cats, there appear to be multiple dietary (and genetic) factors involved. For example, it was theorized that the perceived (not proven) association between lamb meal and taurine status was due to low levels of available amino acids present in the lamb meal, or to excessive heat damage of the protein, or to the confounding factor of the inclusion of rice bran in many lamb meal-containing foods. To date, none of these factors have been conclusively proven or disproven. Although, the most recent study showed that three types of fiber source – rice bran, cellulose, and beet pulp – all caused reduced plasma taurine levels in dogs when included in a marginally low protein diet, with beet pulp causing the most pronounced decrease (11).

Complicated? You bet. This is why it is important to avoid making unsupported claims about certain foods and brands. Taurine-deficiency DCM has been around for a while in dogs and continues to need study before making definitive conclusions about one or more specific dietary causes.

What DO we know? We know that any dietary factor that reduces the availability of taurine precursors, binds taurine bile salts in the intestine, or causes an increase in the bacteria populations that degrade taurine can reduce a dog’s ability to synthesize taurine or will increase taurine degradation and/or loss in the feces. These changes could ultimately compromise a dog’s taurine status (especially if the dog was genetically predisposed) and affect heart health. In extreme cases, as we are seeing, this can lead to taurine-deficiency DCM (see diagram below).

FDA Report: The FDA report identified foods that contain high amounts of peas, lentils, legume seeds, or potatoes to be of potential concern. The FDA also stated that the underlying cause of DCM in the reported cases is not known and that at this time, the diet-DCM relationship is only correlative (not causative). However, this has not stopped various bloggers and even some veterinarians from targeting small pet food companies and/or grain-free brands of food, and implying that these foods, and these foods alone, are causing taurine-deficiency DCM in dogs. Their reasoning is that peas and legumes are present in high amounts in foods that are formulated and marketed as grain-free. However, the truth is that many companies and brands of food include these ingredients. More importantly, there is no clear evidence showing that a particular dog food type, brand, or even ingredient is solely responsible for taurine-deficiency DCM in dogs.

Rather, it is more reasonable and responsible to speculate that one or more of these ingredients, their interactions, or the effects of ingredient quality, heat treatment, and food processing may play a role. Furthermore, the underlying cause could be the protein, starch, or fiber fractions of these ingredients. As plant-source proteins, peas and lentils and legumes include varying amounts of starch (both digestible and resistant forms) and dietary fiber. These protein sources are also generally less nutritionally complete and less digestible than are high quality animal source proteins – additional factors that could influence a dog’s ability to both produce and use taurine. Potatoes, on the other hand, provide a digestible source of starch in an extruded food but also contain varying levels of resistant starch, which is not digested and behaves much like dietary fiber in the intestinal tract.

The Heart of the Matter: Because any or all of these dietary factors could be risk factors for taurine-deficiency DCM in dogs and because peas, legumes, and other ingredients identified by the FDA report have not yet been fully studied, the heart of the matter is that no conclusions can yet be made about the underlying dietary cause or causes of taurine-deficiency DCM in dogs. Given what we do know, a recommendation is to feed a food that contains sufficient levels high quality, animal-source protein, does not include plant-source proteins as its primary protein source, and does not contain high levels of dietary fiber. If you are worried about your dog’s taurine status or heart health, see your veterinarian for a complete physical examination and if needed, to measure plasma levels of taurine.

Cited Studies:

  1. Pion PD, Kittleson MD, Rogers QR, et al. Myocardial failure in cats associated with low plasma taurine: A reversible cardiomyopathy. Science 1987; 237:764-768.
  2. Earl KE, Smith PM. The effect of dietary taurine content on the plasma taurine concentration of the cat. British Journal of Nutrition 1991; 66:227-235.
  3. Hickman MA, Morris JG, Rogers QR. Effect of processing on the fate of dietary taurine in cats. Journal of Nutrition 1990; 120:995-1000.
  4. Hickman HA, Morris JG, Rogers QR. Intestinal taurine and the enterohepatic circulation of taurocholic acid in the cat. Advances in Experimental Medicine and Biology 1992; 315:45-54.
  5. Freeman LM, Rush JE, Brown DJ, et al. Relationship between circulating and dietary taurine concentrations in dogs with dilated cardiomyopathy. Veterinary Therapeutics 2001; 370-378.
  6. Backus RC, Ko KS, Fascetti AJ. Low plasma taurine concentration in Newfoundland dogs is associated with low plasma methionine and cysteine concentrations and low taurine synthesis. Journal of Nutrition 2006; 136:2525-2533.
  7. Ko KS, Backus RC, Berg JR, et al. Differences in taurine synthesis rate among dogs relate to differences in their maintenance energy requirement. Journal of Nutrition 2007; 137:1171-1175.
  8. Fascetti AJ, Reed JR, Roger QR, et al. Taurine deficiency in dogs with dilated cardiomyopathy: 12 cases (1997 – 2001). Journal of the American Animal Veterinary Association 2001; 223:1137-1141.
  9. Delaney SJ, Kass PH, Rogers QR, Fascetti AJ. Plasma and whole blood taurine in normal dogs of varying size fed commercially prepared food. Journal of Animal Physiology and Animal Nutrition 2003; 87:235-244.
  10. Torres CL, Backus RC, Fascetti AJ, et al. Taurine status in normal dogs fed a commercial diet associated with taurine deficiency and dilated cardiomyopathy. Journal of Animal Physiology and Animal Nutrition 2003; 87:359-372.
  11. Ko KS, Fascetti AJ. Dietary beet pulp decreases taurine status in dogs fed low protein diet. Journal of Animal Science and Technology 2016; 58:29-39.

Be There.

We switched to a new veterinarian  last year. We made the change on a good friend’s recommendation and could not be happier. Our new vet is thorough, compassionate, smart as a whip, and an outstanding diagnostician. Her staff members are also competent and welcoming. An additional virtue of this clinic (All About Animals, in Mahomet, IL) is the topic of this essay. Dr. Koss’s standard policy is that owners remain with their dogs and cats for physical examinations and for all health care procedures that good veterinary practice allows.

Here is an example.

Last summer, Cooper (aka Coopa Doopa Doo) developed an ear hematoma.

HOW COOPER SPENDS HIS SUMMERS

I was away, so Mike took him into the clinic. After examination, Dr. Koss recommended a relatively new approach to hematoma treatment in which the site is drained with a large gauge needle and an anti-inflammatory agent is directly injected into the remaining pocket. It is out-patient, does not require anesthesia, and is less invasive than traditional treatment protocols. Because it is a sterile procedure, Cooper would need to be treated in the clinic’s pre-surgery room. Dr. Koss told Mike, who was holding and talking to Coop during the examination, that the room has a large observation window and so Mike could watch as Cooper was being treated, if he so desired.

Mike did so desire. As Coop looked back at him through the window (wagging his tail the entire time), Mike witnessed both the procedure and the gentle way in which Cooper was handled and spoken to throughout treatment.  After the procedure, Caleb, the veterinary technician and Cooper’s new best friend, brought Cooper back out to Mike, and they were good to go. Throughout the entire examination and treatment, Cooper was either with Mike (for weighing, examination and diagnosis) or Mike could see him through the window (during treatment).

Standard Operating Procedure? As many dog folks know, this level of clinic transparency and owner involvement is no longer standard practice at many veterinary clinics. It is quite common today for clinics to require that owners relinquish their dog to a staff person while still in the waiting room. All physical examinations, vaccinations and treatments are then conducted out of sight of the owner in a treatment room and the dog is returned to the owner at the end of the appointment.

Disclaimer: I am going to be blunt. I have a strong opinion about this. There is not a snow ball’s chance that I would allow any of my dogs to be taken “into the back” at a veterinary clinic for anything, short of surgery. Our new vet does go up and above with her clinic’s degree of owner involvement, but we have never been clients at a clinic that required our dogs to be taken away from us for examinations. Just as I assume that parents would not accept such a policy from their child’s pediatrician, I think it is not even remotely acceptable to expect owners to not be present during their pet’s veterinary examinations. Yet, this is not only standard protocol in many clinics today, but a requirement of some for acceptance as a client.

YOU MAY NOT WANT TO TRY TO SEPARATE ME FROM MY DOG.

Yeah, not going to happen. I am my dogs’ advocate as well as their source of comfort and security. Our dogs trust us to have their backs and at no time is this more important than when they are nervous or frightened, a common state of mind of many dogs during veterinary visits.

Until recently, this has only been my opinion. However, a new study, conducted at the National Veterinary School of Alfort in France, examined whether a dog’s stress level during a veterinary examination was influenced by having their owner present and providing comfort (1).

The Study: A group of 33 healthy dogs and their owners were enrolled. The dogs were at least 6 months of age and all had previous experience at a veterinary clinic. The objectives of the study were to measure dogs’ physiological and behavioral responses to a standard veterinary examination and to determine if having the owner present and providing comfort reduced the dog’s level of stress. Heart rate, rectal temperature, ocular (eye) surface temperature, salivary cortisol, and stress-related behaviors were recorded before, during and after a physical examination conducted in a clinic setting. Two conditions were studied: (1) Contact; the owner stood next to the examination table at the dog’s side and comforted the dog by talking to him/her quietly and using gentle petting; (2) Non-contact; the owner was in the room, but did not interact with the dog and sat quietly in a chair located ~ 10 feet away from the examination table. A balanced, cross-over design was used. This means that each dog was subjected to both conditions and experienced two visits (timed 1 to 2 weeks apart). To control for an order effect, the sequence of the conditions varied and was randomly assigned. Examinations lasted approximately 5 minutes and included mild restraint, examination of the dog’s eyes, ears, mouth and teeth, palpation of the lymph nodes and abdomen, manipulation of joints, and heart and lung examination with a stethoscope.

Results: Unsurprisingly, veterinary visits are stressful to dogs:

  • Waiting room stress: All of the dogs experienced at least a low-level of stress during the pre-examination period, in the waiting room. As they waited, many of the dogs showed frequent yawning, which is considered to be a displacement behavior during periods of emotional conflict. Some of the dogs also whined and vocalized.
  • Examination stress: The researchers found that all of the dogs, regardless of whether or not their owner was comforting them, showed a measurable stress response during the veterinary examination. Heart rate, ocular temperature, and lip licking all increased during the examination period.
  •  Owner being there: However, when owners stood close to their dogs and provided comfort by talking to and petting,  the dogs’ heart rates and ocular temperatures decreased when compared with the condition in which owners were not interacting with their dogs. Both of these changes are associated with a decrease in stress. Dogs also attempted to jump off of the examining table less frequently when their owner was comforting them compared with when the owner was not providing comfort.

The authors conclude: “The well-being of dogs during veterinary visits may be improved by affiliative owner-dog interactions”.

UP ON MY SOAP BOX

I know, these results are a no-brainer for many dog folks.

Veterinary visits are stressful to dogs and being present to comfort and reassure our dogs reduces their fear and stress. Unfortunately, in my view, this study did not go far enough, since it did not study the condition that I am most interested in learning about – when dogs are taken away from their owners and examined out of the owner’s presence. Interestingly, the argument that is made to support this practice at the clinics that insist upon it is that they remove dogs from their owners because the presence of the owner can cause the dog to be more stressed, not less so. Well, at the very least, these results provide evidence against that excuse.

And, an excuse it truly is. Perhaps this sounds harsh, (but remember, I am standing on a soap box…..that is what it is for), but my belief is that these policies are in place more for the convenience of the clinic than for the benefit of the dogs. Reducing client interactions in an examination room no doubt is more expedient and efficient (for the clinic). And, there is also that pesky issue of transparency. An owner who does not have the opportunity to witness how their dog is handled, spoken to, examined or treated cannot question or criticize. There is really no other way to say this – the risk of owner displeasure and complaints is reduced by not having owners present while dogs are being examined and treated.

So, personally, I am happy to see these results, as they can be used as evidence when responding to a clinic that insists it is less stressful for dogs to be removed from their owner during examinations and routine procedures. Petting and talking to our dogs when they are upset during a veterinary visit reduces their stress. We have the data. (Not to put too fine a point on it, but these results also provide more ammunition to combat the still-present [and false] belief that calming a fearful dog “reinforces fear“. I address that particular issue in more depth in “Dog Smart“).

Hopefully, we will see a follow-up study that examines dogs’ responses to “no owner present” policies. Regardless, the data that we currently have encourage us to stay with our dogs during veterinary visits and examinations. It is quite simple really.

Just Be There. Insist upon it.

Study Reference: Csoltova E, Martineau M, Boissy A, Gilbert C. Behavioral and physiological reactions in dogs to a veterinary examination: Owner-dog interactions improve canine well-being. Physiology & Behavior 2017; 177:270-281.

 

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).

 

Consider the (Caregiver) Placebo Effect

Most people are familiar with the concept of a “placebo effect”, the perception of improved health while unknowingly receiving a sham (placebo) treatment that in reality should have no benefit at all. Growing up, my mother referred to this as “giving someone a sugar pill”. The assumption is that because we believe that we are receiving an actual treatment, our mind tells us that we should feel a bit better. Then amazingly, we do feel better. We notice a reduction in symptoms and ultimately conclude that the “medicine” must be working. The irony is that placebos actually can be powerful medicine (or something), at least for some people, for some diseases, some of the time.

placebo-comic

Placebos and Us: The effects of placebos in human medicine are well-documented and are described with human diseases of almost every type. The highest level of placebo effect is seen with diseases that have subjective symptoms that are patient-reported and difficult to measure directly, that tend to fluctuate in severity, and that occur over long periods of time (i.e. are chronic). Examples include depression, anxiety-related disorders, gastric ulcer, asthma, and chronic pain. In medical research, an average placebo response rate of 35 percent is reported, with rates as high as 90 percent for some health conditions. By any standard, that is a whole lot of sugar pill response going on.

placebo

Placebo Control Groups: Although the reasons that we respond to placebos are not completely understood, medical researchers universally accept the importance of considering them when studying new treatments. Studies of new drugs or medical interventions include placebos as control groups to allow unbiased comparisons with the treatment or intervention that is being evaluated. Any effect that the placebo group shows is subtracted from the effect measured in subjects who are receiving the actual medication. The difference between the two is considered to be the degree of response attributable to the treatment. If a placebo control group was not included, it would be impossible to differentiate between a perceived response (placebo) and a real response to the treatment. Today, double-blind, placebo-controlled clinical trials are considered to be the Gold Standard of study designs by medical researchers. The “double-blind” part refers to the fact that in addition to having both a placebo group and a treatment group, neither the researchers nor the subjects know which subjects are getting the treatment and which are getting the placebo. (For more information about double-blind research trials with dogs, see “Thyroid on Trial“).

What about Dogs? Can a placebo effect occur with dogs? Possibly, but things work a bit differently where our dogs are concerned. Most obviously, while highly communicative in many ways, dogs cannot specifically tell us what part of their body is in pain, how intense that pain is, if it is abating, or by how much. Rather, we use our knowledge of a dog’s behavior and body language to determine how he is feeling. As their caregivers, we are the recorders and the reporters of our dogs’ health, symptoms, and response to treatments. Similar to human studies, this is most relevant when the symptoms are things that are not easily measured using medical tests and that are more subjective in nature.

A second important difference is that dogs are basically always blinded to treatments. Although they may understand that something different is being done to them (or that there is a strange pill buried in that piece of cheese), most people will agree that dogs do not have an understanding that they are being medicated for a particular health problem or are on the receiving end of a new behavior modification approach. As a result, unlike human patients, dogs lack the specific expectations and beliefs about health interventions that may be necessary for a placebo effect to occur directly. However, because it is the owner who reports many symptoms and changes in health to their veterinarian and also who conveys subjective information regarding the dog’s response to a given treatment, a different type of placebo effect may be in action with dogs. This is called a “caregiver placebo effect”. As with human maladies, the conditions for which this type of placebo effect has been described in dogs are those that involve subjective measures of health (pain, activity level, appetite) and that have a tendency to fluctuate in severity.

Let’s look at two examples – the caregiver placebo effect in dogs with osteoarthritis and in dogs with epilepsy.

Does Your Dog Hurt Less? Osteoarthritis is a painful and progressive health problem that can seriously impact a dog’s quality of life. A variety of medical and nutritional treatments are available today for afflicted dogs. These range from NSAIDS (ex. deracoxib, meloxicam), nutrient supplements (ex. glucosamine, chondroitin sulfate) to alternative medicine approaches (acupuncture, cold laser therapy). Researchers who have studied these treatments use subjective measures of lameness in which dogs’ owners and veterinarians numerically rate their dog’s degree of pain, mobility, and interest in daily activities in response to treatment. Some, but not all, studies also include objective measurements of arthritis that quantify the amount of weight-bearing in the affected legs and weight distribution in the body.

Arthritis Studies: In virtually all placebo-controlled studies of this type, a substantial proportion of owners and veterinarians have reported improvement in the placebo-treated dogs. However, when measured using weight-bearing techniques, the dogs in the placebo group showed no change in or a worsening of disease. Michael Conzemius and Richard Evans at the University of Minnesota’s College of Veterinary Medicine decided to quantify the actual magnitude of the placebo effect in this type of experimental trial (1). They analyzed the data from 58 dogs who were in the placebo control group of a large clinical trial that was testing the effectiveness of a new NSAID. All of the enrolled dogs had been diagnosed with osteoarthritis and had clinical signs of pain and changes in gait and mobility. This was a multi-centered design, which means that each dog’s own veterinarian conducted the bi-weekly evaluations of gait and lameness. Both owners and veterinarians completed questionnaires that measured whether the dog showed improvement, no change, or worsening of arthritis signs over a 6-week period. Neither the owners nor the veterinarians knew if their dog was receiving the placebo or the new drug.

Results: Half of the owners (50 percent) stated that their dog’s lameness decreased during the study, 40 percent reported no change, and 10 percent said that their dog’s pain had worsened. When these reports were compared with actual change as measured by force platform gait analysis, the caregiver placebo effect, (i.e. thinking that improvement occurred when there was either no change or an actual worsening of signs), occurred in 40 percent of owners. The veterinarians performed no better. A placebo effect occurred 40 to 45 percent of the time when veterinarians were evaluating dogs for changes in gait or pain. This means that not only were the owners strongly invested in seeing a positive outcome, so too were their veterinarians. This effect occurred despite the fact that all of the human participants were aware that their dog had a 50 percent chance of being in the placebo group or the drug group, and that there was no way to be certain which group their dog was in.

Seizure Study: This study used an approach called a “meta-analysis” which means that the researchers pooled and then reexamined data collected from several previous clinical trials (2). Veterinarians from North Carolina State University College of Veterinary Medicine and the University of Minnesota reviewed three placebo-controlled clinical trials that examined the use of novel, adjunct treatments for canine epilepsy. During the treatment period owners were asked to record all seizure activity, including the length of the seizure, its intensity, and the dog’s behavior before and immediately following the seizure. The pooled results showed that the majority of owners of dogs in the placebo group (79 %) reported a reduction in seizure frequency in their dog over the 6-week study period. Almost a third of the owners (29 %) said that there was a decrease of more than 50 percent, the level that was classified in the study protocols as indicative of a positive response to treatment.

What’s Going On? Well, several things, it appears. The most obvious explanation of the caregiver placebo effect in dogs is owner expectations of a positive response when they assume an actual treatment is being administered to the dog. Whenever we introduce a new medication or diet or training method and anticipate seeing an improvement in our dog’s health, nutritional well-being or behavior, we naturally tilt toward seeing positive results and away from seeing no change (or worse – a negative effect). This is a form of confirmation bias – seeing what we expect to see and that confirms our preexisting beliefs. In fact, an early study of the caregiver placebo effect in dogs found that when owners were asked to guess which group their dog was in, the owners who said that they were certain that their dog was in the treatment group (but was actually in the placebo group) demonstrated the strongest placebo effect (3).

Such expectations may be an especially strong motivator when we are dealing with maladies that have affected our dog for a long time, infringes upon the dog’s ability to enjoy life, and for which we feel that we are running out of options. Osteoarthritis and seizure disorders were the health conditions studied in these papers, but I can think of several other problems with our dogs for which we may easily succumb to the power of the placebo effect. These include chronic allergies, adverse reactions to food ingredients, anxiety-related behavior problems and even cancer.

Cognitive Dissonance: Another factor that may contribute to the caregiver placebo effect is finding oneself in a state of contradiction. When we invest time and money (and hope) into a new treatment for our dogs, it follows that we will naturally have high expectations that the treatment will work. Indeed if it does not, we may experience cognitive dissonance, the uncomfortable feeling caused by holding two contradicting beliefs in one’s mind at the same time. For example, “I was told that giving my dog dehydrated gooseberry rinds would cure his chronic itching; these rinds are expensive and hard to find. He does not seem any better…… Uh oh. This is not a good feeling….”

Psychologists tell us that our brain reduces this discomfort for us (without our conscious awareness, by the way) by simply changing our perceptions. “Oh look! I am sure that the dehydrated gooseberry rinds ARE finally working. It just too some time – several months in fact. Still the effect MUST be the gooseberry rinds. YAY!”  In this case, convincing oneself that the dog does seem a bit less itchy, her coat is a bit healthier and overall, she does really seem to be feeling better, immediately solves this problem for the brain and for our comfort level.

cognitive-dissonance

The Hawthorne Effect: Finally, a related phenomenon that is common enough to have earned its own name is the Hawthorne Effect, also called observation bias. This is the tendency to change one’s behavior (or in our case how one reports their dog’s behavior) simply as a result of being observed. The Hawthorne Effect suggests that people whose dogs are enrolled in an experimental trial may behave differently with the dog because they know they are enrolled in a trial that is measuring many aspects of the dog’s life. In the case of the arthritis studies, owners may have altered how regularly they exercised their dogs, avoided behaviors that worsened the dog’s arthritic pain, or began to pay more attention to the dog’s diet and weight.

The point is that when people are enrolled in a research trial or are starting a new medical treatment, diet, or training program and are being monitored, they will be inclined to change other aspects of how they live with and care for the dog as well. These changes could be as important (or more important) than the actual treatment (or placebo). This is not necessarily a bad thing, mind you, and is another reason why we always need control groups, but the occurrence of the Hawthorne Effect emphasizes the importance of recognizing that the thing that we think is working for our dog may not actually be the thing that is doing the trick.

Take Away for Dog Folks: When trying something new with our dogs, might we, at least some of the time, in some situations, be inclined to see improvement when it does not truly exist? When interpreting our dog’s response to a novel therapy or supplement or training technique are we susceptible to falling for the sugar pill? It seems probable, given the science. It is reasonable to at least consider the possibility that a placebo effect may be influencing our perceptions of our dog’s response to a new food, a new supplement, a new training technique or a novel treatment. This is especially true if the approach that we are trying has not been thoroughly vetted by research through double-blind, placebo-controlled trials. While the development of new medications and foods and training methods is exciting and important, we must avoid the tendency to see improvement from something that is novel simply because we expect and desire it to be so.

CITED STUDIES:

  1. Conzemium MG, Evans RB. Caregiver placebo effect of dogs with lameness from osteoarthritis. Journal of the American Veterinary Medical Association 2012; 241:1314-1319.
  2. Munana KR, Zhang D, Patterson EE. Placebo effect in canine epilepsy trials. Journal of Veterinary Internal Medicine 2010; 24:166-170.
  3. Jaeger GT, Larsen S, Moe L. Stratification, blinding and placebo effect in a randomized, double blind placebo-controlled clinical trial of gold bead implantation in dogs with hip dysplasia. Acta Veterinaria Scandinavica 2005; 46:57-68.

Excerpted from: “Beware the Straw Man: The Science Dog Explores Dog Training Fact and Fiction” (2015).

Beware Straw Man Cover

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.

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

coversnip

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.