Welcome to Part 2 of the Virchew series on our dog's digestive system! In Part 1, we explored the canine digestive system and the role of the microbiome in optimal health and potential disease prevention.

In this blog, we're digging into a few studies that demonstrate dogs can meet their nutrient requirements in a nutritionally balanced vegan, plant-protein diet and details on a few important Virchew ingredients that support the digestive process and the microbiome - such as beta-glucan fibre. Then we will touch on common food allergens in dogs that can manifest as skin and/or tummy issues. Healthy digestion and nutrient adequacy are the foundational pillars for a dog's happy and healthy life!

Digestibility of Plant Foods in Dogs

In a complete and balanced plant-based diet, macronutrients and micronutrients are available in amounts set by the Association of American Feed Control Officials (AAFCO) for dog nutrition, just as they are in commercial meat-based foods. Due to their domestication alongside humans for 10,000 to 20,000 years, dogs' digestive system has evolved to better digest starches (carbohydrates) than wolves; and, therefore, can derive nutrients and energy from plants!

The 2013 study compared the dog genome (genetic information in an organism's DNA) to their wolf ancestors and found two significant genetic differences: genes responsible for starch digestion, fat metabolism, and behaviour attributes.

Numerous study experiments have assessed the adequacy of a vegetable-based diet for dogs that attest to the evolutionary survival adaption. In one study, published in the British Journal of Nutrition in 2009, researchers wanted to determine if highly active sprint-racing huskies could meet their nutritional requirements on nutritionally balanced meat-free diets compared to meat-based ones. Hematological results were within the typical values for all dogs. Veterinarians blinded to the dietary regimens assessed all dogs as being in excellent physical condition. No dogs developed anemia or other detectable health problems in this study.

In a 2016 study published in the Animal Journal, researcher Andrew Knight from the University of Winchester (UK) made a comprehensive assessment of previous studies on vegetarian versus meat-based diets for companion animals. One of the observations is described as follows:

"A growing body of evidence appears to indicate that dogs and cats can survive, and indeed thrive, on nutritionally-sound vegetarian and vegan diets. Benefits commonly reported after transitioning dogs and cats to nutritionally sound vegan or vegetarian companion animal diets include decreased ectoparasites (fleas, ticks, lice, and mites) and food intolerance reactions; improved coat condition; obesity reduction; regression in signs of arthritis; diabetes; cataracts; urogenital disease; and improved vitality." ~ Andrew Knight.

NOTE: This study emphasizes the importance of formulating a carefully balanced vegan or vegetarian diet that complies with the AAFCO’s Dog Nutrient Profile for the specific life stage. However, dog parents should be aware that nutritional adequacy is also a concern prevalent in commercial meat-based diets.

Another essential factor is the digestibility of plant products, as we want to assure our furry friends adequately digest and absorb all the required nutrients their body needs. Digestibility represents the amount of a specific nutrient absorbed by a dog and is calculated by subtracting the amount of nutrient retained in the fecal matter by the amount consumed.

A 2019 study by the University of Guelph examined the mineral digestibility of ingredients in animal and vegetable-based pet food as current knowledge focus on supplemented minerals. Eight purpose-bred beagles were fed either animal or vegetable protein-based diets formulated to meet the nutritional requirements of adult dogs and a diluted version of both diets.

The dogs were randomly assigned to one of the diets for ten days, and fecal samples were collected on the last four days of feeding. The study found that the apparent mineral digestibility was lower in the dogs fed diluted diets (p<0.05). True digestibility of phosphorous, copper, magnesium, zinc, and manganese were higher for dogs fed the vegetable-based diet than the animal-based diet.

This study shows that dogs can absorb minerals from both animal and vegetable-based ingredients. However, the apparent digestibility results indicate that a vegetable-based diet can supply and exceed the required minerals for adult dogs.

Recent and promising research by Andrew Knight was published in April 2022. This was the first large-scale study to outline the different health outcomes of dogs kept on a vegan or meat-based diet. The researchers surveyed 2,536 pet parents that fed their dog primarily conventional meat (1,370 = 54%), raw meat (830 = 33%) or vegan (336 = 13%) diet for at least one year. The general health indicator included seven factors: the number of veterinary visits, medication use, and the number of unwell dogs, among others.

The overall health results show that dogs fed conventional meat were the least healthy within the three categories. Furthermore, the study highlights the significant evidence of the dietary hazards (nutritional imbalances and pathogens) of raw meat diets. Based on the evidence from this survey and previous scientific research in this field, the study concludes that when equally considering health impact and dietary risks, the healthiest and safest dietary choices for dogs are nutritionally sound vegan diets!

UPDATE OCTOBER 2024 - See our detailed and current research blog for several more studies on plant-based nutrition for dogs studies over the past 2 years!

Key Ingredients in Virchew's LOVE Bowl for Optimal Health

Veterinary nutritionists formulated the Virchew LOVE Bowl to meet a dog's nutrient requirement for adult dogs. It contains wholesome, nutrient-dense plant ingredients like peas, oats, potatoes, hemp hearts, golden algae, etc. In addition, a custom blend of supplements is added to the food to be nutritionally complete and balanced.

Pea Protein consists primarily of globulins and a small fraction of albumin proteins. The globulins are storage proteins located in the pea cotyledons and comprise protein subunits legumin, vincilin and convicilin. It has low levels of anti-nutritional factors and non-allergenic properties.

Hemp Hearts are full of healthy fats, proteins, fibre, and minerals, making hemp a nutritional powerhouse. We have posted an entire blog dedicated to hemp; read more here.

Oats are a great alternative carbohydrate for dogs that may be sensitive to wheat or grains since they're naturally gluten-free. Oatmeal contains vitamin B, which helps maintain a healthy coat, and linoleic acid, a type of omega-6 fatty acid that helps keep a dog's skin firm and healthy. Oats are one of the richest sources of beta-glucan, insoluble fibre, which modulates the immune system. Fibre presented in oats can regulate blood glucose levels and help dogs with irregular bowel movements. Oat beta-glucans for dogs show promising research. Check out this study.

Potatoes are an excellent source of vitamins and B6, along with the minerals iron and magnesium. Potatoes are also a great source of fibre, essential for your dog's digestive health. Soluble fibre supports the natural probiotic bacteria in the gut, which promotes excellent health, as previously discussed in Part 1. This helps to keep your pooch's poops happier and healthier. 😃

Dried Golden Algae are a source of long-chain amino acidic DHA. It also contains small amounts of EPA and several vitamins and minerals. In addition, golden algae are another source of the insoluble fibre, beta-glucan. Want to learn more about golden algae? Fetch here.

Canine Food Allergies or Sensitivities

A 2015 study (RS Mueller, T Olivry, P. Prelaud) shows that beef, dairy products, chicken, and wheat are the most potential food allergens contributing to dogs' cutaneous adverse food reactions (CAFR). Other common food allergens are lamb, chicken eggs, and soy; when a dog eats any of these substances, an antibody response occurs, and symptoms show up. Therefore, a period of dietary restrictions (also known as an elimination diet) is often recommended until clinical symptoms disappear.

Common symptoms:

• Ear infections

• Digestive upset: vomiting or diarrhea

• Licking and chewing on the legs and paws

• Itchy skin

• A variety of skin lesions that may improve with treatment but then reoccur

Less common symptoms:

• Weight loss

• Hyperactivity

• Lethargy

• Increased aggression

Most of the foods that cause allergies or sensitivities in dogs are derived from animals. For example, it is common for veterinarians and licensed veterinary nutritionists to prescribe specific meat-free diets to treat CAFR and other health conditions. However, Virchew meals and treats do not contain any of the foods that are likely to cause sensitivities in dogs. Therefore, Virchew is considered an ideal hypoallergenic choice as a high-quality plant-based food!

Although not all diets are created equal, a nutritionally formulated, complete and balanced plant-based diet is an excellent option to meet all nutrient requirements for your dog and avoid dietary imbalances.

Some food for thought: Like us, animals do have requirements for nutrients, but not necessarily certain foodstuffs or ingredients so why not choose a powerfully healthy, plant-based food for your pup, which is a more sustainable option?!

And last but not least, check out the tummy success stories of Virchew customers, like Rowdy here. Rowdy had mysterious discomfort, but that's all gone now!

Does your pup want a free sample of Virchew? (Available only in Canada at this time!) Fetch it here.

ABOUT THE WRITER

Tatiana Victorino is a nutrition research consultant for Virchew. She received her BSc in Food Engineering at UNICAMP, an internationally recognized center of academic excellence in Brazil and also holds a BCIT Operations Management certificate. With over 5-years of professional experience working in the food and beverage manufacturing industries, Tatiana has also gained dynamic expertise in process design and improvement, lean manufacturing, business operations, quality assurance, and research and development. 

References

Cummings School of Veterinary Medicine at Tufts University:

https://vetnutrition.tufts.edu/2016/07/vegan-dogs-a-healthy-lifestyle-or-going-against-nature/

Can Dogs Eat Oatmeal?:

https://www.akc.org/expert-advice/nutrition/can-dogs-eat-oatmeal

Plant-based Diets are the Best Hypoallergenic Dog Food: https://www.canadianpetconnection.ca/why-plant-based-diets-are-the-best-hypoallergenic-dog-food

Food Allergies in Dogs. By Catherine Barnette, DVM; Ernest Ward, DVM: https://vcacanada.com/know-your-pet/food-allergies-in-dogs