Category Archives: dog nutrition and labelling

Fresh and raw diets for dogs may have health benefits

Many dog owners think of their furry companions as part of the family, and now products are available to feed them that way, too. Some owners are moving away from traditional extruded kibble products, instead choosing ultra-premium fresh and raw diets found in the refrigerated aisle. The foods may look more similar to what we’d feed a member of the family, but many of the newer diets haven’t been rigorously tested for performance in dogs.

Beagle feeding study

“A lot of companies test for complete and balanced nutrition, but don’t go beyond that,” says Kelly Swanson, corresponding author on a new study published in the Journal of Animal Science and Kraft Heinz Company Endowed Professor in Human Nutrition in the Department of Animal Sciences and the Division of Nutritional Sciences at the University of Illinois. “The company we worked with – Freshpet – wanted to see how some of their unique diets would perform. Would dogs like them? Were they digestible? Would they increase activity?”

The researchers tested the palatability and digestibility of three commercially marketed fresh and raw diets for dogs, as well as a traditional extruded kibble diet. The diets included a lightly cooked roasted-refrigerated diet; a lightly cooked grain-free roasted-refrigerated diet; and a raw diet. The lightly cooked roasted diets were pasteurized, and the raw diet was treated with an acidifying bacteria that makes the food inhospitable to harmful microbes.

“The roasted diets come in a meatball form, and the raw diet was more like a big sausage roll that you cut up and feed to the dog. All diets were chicken-based, but some had added beef, salmon, or chicken liver. Each diet also contained a vitamin and mineral mix, and a dry mix of plant products like sweet potatoes, kale, spinach, cranberries, and carrots,” Swanson says. “People are familiar with those ingredients so they like to see them included in their pets’ diets. Although specific ingredients are not needed in the diet of dogs and cats, as many options can result in an acceptable nutrient profile, those ingredients are of high quality and are nutrient dense.”

Eight beagles were successively fed each diet for one month. After a 14-day transition period onto each new diet, they were monitored for voluntary physical activity, and then urine, stool, and blood samples were collected and analyzed.

The roasted diets turned out to be more digestible than the kibble, and both the grain-free roasted diet and the raw diet resulted in lower blood triglyceride levels than the kibble diet, even though they were higher in fat. Swanson isn’t able to pinpoint the cause of the surprising result, but points to it as a potential benefit of the non-traditional diets. Voluntary activity didn’t differ across the diets.

The researchers also found major shifts in the microbiota – the suite of microbes inhabiting the gut – in the roasted and raw diets, compared with kibble. Swanson says the changes in the microbiota were neither good nor bad, just different. He suggests that the results showcase the flexibility of gut microbiota, and how little scientists know about the effects of diet on host-microbe relationships as a whole.

It is important to point out that all dogs were healthy throughout the study period, and that all diets were palatable, highly digestible, and resulted in good stool quality. Even though some of the diets were statistically more digestible or led to lower triglycerides, those metrics were within the normal range for all dogs on all diets. Therefore, Swanson emphasizes, all the diet formats tested in the study, including kibble, would be healthy choices.

“As far as diet format and market segment is concerned, it ultimately comes down to consumer preference and philosophy. As long as a diet is shown to be safe and meets the nutritional needs of the pet in question, it is an acceptable option to me. If an owner is willing to pay more for premium ingredients and/or an improved processing method, I am fully supportive. To me, the most important thing is testing these new diet formats and products before they are commercially available,” Swanson says.

The article, “Apparent total-tract macronutrient digestibility, serum chemistry, urinalysis, and fecal characteristics, metabolites and microbiota of adult dogs fed extruded, mildly cooked, and raw diets,” is published in the Journal of Animal Science [DOI: 10.1093/jas/sky235]. Authors include Kiley Algya, Tzu-Wen Cross, Kristen Leuck, Megan Kastner, Toshiro Baba, Lynn Lye, Maria de Godoy, and Kelly Swanson. Lynn Lye is from Freshpet, and all other authors are from U of I. The research was funded by Freshpet.

Source:  University of Illinois press release

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Do grain-free diets really cause canine heart disease?

You may have heard that on July 12th, the US Food and Drug Administration issued a statement that it was investigating a potential connection between grain-free diets and canine heart disease:

The U.S. Food and Drug Administration is alerting pet owners and veterinary professionals about reports of canine dilated cardiomyopathy (DCM) in dogs eating certain pet foods containing peas, lentils, other legume seeds, or potatoes as main ingredients. These reports are unusual because DCM is occurring in breeds not typically genetically prone to the disease. The FDA’s Center for Veterinary Medicine and the Veterinary Laboratory Investigation and Response Network, a collaboration of government and veterinary diagnostic laboratories, are investigating this potential association.

Canine DCM is a disease of a dog’s heart muscle and results in an enlarged heart. As the heart and its chambers become dilated, it becomes harder for the heart to pump, and heart valves may leak, leading to a buildup of fluids in the chest and abdomen. DCM often results in congestive heart failure. Heart function may improve in cases that are not linked to genetics with appropriate veterinary treatment and dietary modification, if caught early.

The underlying cause of DCM is not truly known, but is thought to have a genetic component. Breeds that are typically more frequently affected by DCM include large and giant breed dogs, such as Great Danes, Boxers, Newfoundlands, Irish Wolfhounds, Saint Bernards and Doberman Pinschers. It is less common in small and medium breed dogs, except American and English Cocker Spaniels. However, the cases that have been reported to the FDA have included Golden and Labrador Retrievers, Whippets, a Shih Tzu, a Bulldog and Miniature Schnauzers, as well as mixed breeds.

Full text of the FDA statement here.

Investigating possible links is always a good thing; but equally concerning is understanding what data backs up any claim.

Pet Business magazine points out that the data backing up the link is very thin – at this point unlikely to pass the rigor of a peer-reviewed journal.  Obviously an industry body has concerns about the impact of consumer choices  and the impact on sales, but it is right that they point out that the data set so far is quite limited.

I follow research regularly, and I’m always open to findings that may cause us to re-think our choices of food and other healthcare strategies for our dogs.

But let’s be sure about evidence.

The availability and variety of grain-free foods has increased dramatically in recent years, as cases of itchy dogs and dietary intolerances caused by corn and wheat have been documented.  Who’s to say that grain-free carbohydrates like peas, lentils and potatoes might not also come with side effects?

And all of this debate reinforces my belief in the hybrid diet.  Sometimes raw, sometimes kibble, and sometimes homemade.  Diversification is a strength!

Kathleen Crisley, specialist in dog massage, rehabilitation and nutrition/food therapy, The Balanced Dog, Christchurch, New Zealand

Hunting dogs may benefit from antioxidant boost in diet

Free radicals, those DNA-damaging single-oxygen atoms, are produced in spades during exercise. Dogs that exercise a lot, like hunting dogs, may need to consume more antioxidants than their less-active counterparts to protect against this damage. But what diet formulation best meets the needs of these furry athletes? A new University of Illinois study provides some answers in a real-world scenario.

Hunting dogs

Researchers visited a kennel of American Foxhounds in Alabama over the course of a hunting season, providing one group a high-performance commercial diet and another group a test diet similar to the commercial diet, but with added antioxidants (vitamins C and E, and lutein), zinc, and taurine. During the study, dogs from both groups went on two to three hunts per week, each 2 to 5 hours in length.

“We think of it as unstructured endurance exercise. They’re not running the entire time. They might stop to sniff or go more slowly to pick up a scent,” says Kelly Swanson, corresponding author on the study and Kraft Heinz Company Endowed Professor in Human Nutrition in the Department of Animal Sciences and the Division of Nutritional Sciences at U of I.

Before starting the diets and on four occasions during the seven-month study, researchers took blood samples from the dogs to examine oxidative stress markers and other blood metabolites.

“We hypothesized that dogs fed the test diet would have a lower concentration of oxidative stress markers and improved performance compared to the dogs fed the commercial diet,” Swanson says. “It turns out performance wasn’t affected by diet, but the test diet did improve indirect measures of oxidative stress. Therefore, improved performance may be expected with more strenuous exercise when metabolic demands are higher.”

The amino acid taurine, once thought to be non-essential for dogs but now recognized as an important nutrient for heart health, declined over the course of the season for dogs fed the commercial diet. The same pattern occurred with vitamin E. Although one dog did come close to a critically low level of taurine during the study, all dogs fed the commercial diet stayed within the normal range for all blood metabolites.

For dogs fed the test diet, taurine and vitamin E levels were maintained at or above the baseline. The results suggest to Swanson and his co-authors that these compounds are compromised in athletic dogs over months of unstructured exercise, and more-active dogs such as sled dogs may experience greater depletion.

“We can conclude that athletic dogs may benefit from supplementation of vitamin E and taurine to minimize oxidation and maintain taurine status,” he says.

The article, “Longitudinal changes in blood metabolites, amino acid profile, and oxidative stress markers in American Foxhounds fed a nutrient-fortified diet,” is published in the Journal of Animal Science [DOI: 10.1093/jas/skx070]. Funding was provided by The Nutro Company.

Source:  University of Illinois press release

Dogs could be more similar to humans than we thought

Dog and human gut microbiomes have more similar genes and responses to diet than we previously thought, according to a study published in the open access journal, Microbiome.

Canine Microbiome

The canine microbiome is quite similar to that of humans. Credit: © Kar Tr / Fotolia

Dr Luis Pedro Coelho and colleagues from the European Molecular Biology Laboratory, in collaboration with Nestlé Research, evaluated the gut microbiome of two dog breeds and found that the gene content of the dogs microbiome showed many similarities to the human gut microbiome, and was more similar to humans than the microbiome of pigs or mice.

Dr Luis Pedro Coelho, corresponding author of the study, commented: “We found many similarities between the gene content of the human and dog gut microbiomes. The results of this comparison suggest that we are more similar to man’s best friend than we originally thought.”

The researchers found that changes in the amount of protein and carbohydrates in the diet had a similar effect on the microbiota of dogs and humans, independent of the dog’s breed or sex. The microbiomes of overweight or obese dogs were found to be more responsive to a high protein diet compared to microbiomes of lean dogs; this is consistent with the idea that healthy microbiomes are more resilient.

Dr Luis Pedro Coelho, commented: “These findings suggest that dogs could be a better model for nutrition studies than pigs or mice and we could potentially use data from dogs to study the impact of diet on gut microbiota in humans, and humans could be a good model to study the nutrition of dogs.

“Many people who have pets consider them as part of the family and like humans, dogs have a growing obesity problem. Therefore, it is important to study the implications of different diets.”

The researchers investigated how diet interacted with the dog gut microbiome with a randomized controlled trial using a sample of 64 dogs, half of which were beagles and half were retrievers, with equal numbers of lean and overweight dogs. The dogs were all fed the same base diet of commercially available dog food for four weeks then they were randomized into two groups; one group consumed a high protein, low carb diet and the other group consumed a high carb, low protein diet for four weeks. A total of 129 dog stool samples were collected at four and eight weeks. The researchers then extracted DNA from these samples to create the dog gut microbiome gene catalogue containing 1,247,405 genes. The dog gut gene catalogue was compared to existing gut microbiome gene catalogues from humans, mice and pigs to assess the similarities in gene content and how the gut microbiome responds to changes in diet.

The authors caution that while humans and dogs host very similar microbes, they are not exactly the same microbes, but very closely related strains of the same species.

Source:  Science Daily

Your dog’s poo

They say that the eyes are the window to the soul; in many ways your dog’s poo is a window on their health.

(I never thought I’d see the day when I wrote about poop – but there’s a first time for everything.)

Have you noticed that the color of your dog’s poo changes with what they are fed?  For example, if you are feeding raw venison, chances are the poo is quite dark.

If, however, the stool has a noticeably black color such as in this photo, this can indicate digested blood and you should be off the vet for a check (don’t be shy, take a sample with you!).

A yellow or slightly green tone indicates a rapid transit time in the bowel, typical if your dog has had diarrhea, as in below.  But consistently soft stools can also be an indicator of bowel disease such as IBD.

Diarrhea or loose stool

A white or chalky color to the stool indicates a very high content of calcium, often found in dogs that are being fed raw with a high bone content.  If your dog is passing stools of this color, they are at risk of constipation from the bone material they are ingesting because of the dryness and risk of impaction.  In my practice, I am seeing  instances of poor mixing of raw foods and it usually from the same supplier – which is why I recommend only certain sources of food to my customers.

White chalky stools, an indicator of high bone content

If you see bright red blood in the stool, it’s also time to talk to your vet and of course, if you see visible worms than a vet visit is also recommended.

And finally, if your dog passes poos that are a neon green in color, they’ve been exposed to rat or mice poison and urgent attention is needed.

Kathleen Crisley, specialist in dog massage, rehabilitation and nutrition/food therapy, The Balanced Dog, Christchurch, New Zealand

 

Most dog treats exceed recommended daily energy allowance

Most commercially available dog treats contain a range of undefined ingredients, including sugars, and often exceed the recommended daily energy allowance for treats (‘complementary feed’), warn researchers in the Vet Record.

They say treat labels should be more explicit and provide more detailed information on ingredients and energy content to prevent dogs becoming overweight or obese and at increased risk of conditions like diabetes.Chicken jerky treats for dogs

Dog treats represent the fastest growing segment of the pet food industry. European regulation states that dog treats should be labelled as ‘complementary feed’ and sets out rules for labelling to provide adequate information for consumers.

World Small Animal Veterinary Association (WSAVA) guidelines also state that daily treat intake should not exceed 10% of a dog’s energy needs (known as maintenance energy requirement or MER).

But little is known about the nutritional value of treats and their impact on the dog’s diet, health and wellness, despite the popularity of such products.

So researchers led by Giada Morelli at the University of Padua in Italy, set out to compare the nutrient composition of different categories of treats and to verify whether daily intake recommendations on the label were in accordance with WSAVA guidelines.

They identified 32 popular dog treats available in pet shops and supermarkets (five biscuits, ten tender treats, three meat-based strips, five rawhides [dry bovine skin], twelve chewable sticks and six dental care sticks).

Products were analysed for levels of minerals, starch, simple sugars (glucose, fructose and sucrose) and the amino acid hydroxyproline (a component of collagen).

They found that three out of four (76%) of treats contained between four to nine ingredients, and that ingredients were not precisely described on the label. For example, biscuits and dental sticks had ‘cereals’ listed as the first ingredient, while tenders, meat strips, rawhides and chewable sticks had ‘meat and animal derivatives’ listed first.

Almost half of products mentioned ‘sugars’ on the label’s ingredient list and all contained varying amounts of minerals.

The most calorically dense treats were biscuits, whereas the least calorically dense were dental sticks. When caloric density was expressed as kcal/treat, rawhides were the most energy-dense products, followed by chewable sticks and dental sticks.

When manufacturers’ feeding instructions (number of treats/day) were followed, on average, biscuits accounted for 16% of MER for dogs of any size; rawhides exceeded 25% MER for small-sized dogs and 18% MER for medium-sized dogs. Chewable sticks surpassed 10% MER for all size dogs, reaching 16.9% MER in small-sized dogs. Only feeding instructions for dental sticks remained below 10% MER for every dog size.

This is the first investigation to categorise dog treats and determine their nutrient profile,” write the authors.

They point to some study limitations, such as the small number of treats that were analysed in each category. Also, these results may not be representative of all products worldwide given the wide number of dog treats available on the market.

Nevertheless, they say their results suggest that treat labelling should include more information on the ingredients used, and that producers should reconsider the feeding instructions they provide on labels, especially for small dogs.

Caution should also be adopted when considering treats for dogs with specific ingredient sensitivities or in dogs with conditions such as heart failure and kidney disease due to their potential high mineral content, they add. Finally, they say future studies should sample a greater number of products to provide more precise data.

Source:  Science Daily media release

Journal reference: Giada Morelli, Eleonora Fusi, Sandro Tenti, Lorenzo Serva, Giorgio Marchesini, Marianne Diez, Rebecca Ricci. Study of ingredients and nutrient composition of commercially available treats for dogs. Veterinary Record, 2017; vetrec-2017-104489 DOI: 10.1136/vr.104489

Fish oil supplements – beware!

I regularly see posts on Facebook about supplementing dogs with fish oils.  I meet new clients fairly regularly who feel they are doing the right thing by feeding fish oil supplements to their dogs as a source of Omega 3 and for anti-inflammatory support.

However, most owners seem unaware of the studies that most commercial fish oil supplements in New Zealand are oxidised – meaning that the levels of polyunsaturated fatty acids is dramatically lower than claimed on the label.  I’m not in favour of ingesting rancid oils!

In fact, this 2015 study found that only 8% of the supplements tested in the New Zealand market met the levels expected by international recommendations.  And higher-priced supplements and those with brand name labels were no indicators of better quality.

Another study based on supplements available in Canada showed that 50% of the supplements tested were oxidised.

In keeping with my philosophy of food as a source of wellness, I’ve moved away from the concept of fish oil supplementation using commercial supplements and instead choose real-life salmon and sardines as a source of fish oils.

If I was a dog, I’d choose a few sardines over a fish oil capsule any day!

tinned sardines

Kathleen Crisley, specialist in dog massage, rehabilitation and nutrition/food therapy, The Balanced Dog, Christchurch, New Zealand