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August 13, 2021

The Truth About Mixes And Ingredient Quality

by Dr. Cayla Iske, PhD

Muesli and seed-based mixes have populated the small animal food aisle for decades. The ingredient profile for these products will vary, but most mixes consist of a mixture of loose components including various combinations of the following:  

  • Cereals
  • Legumes
  • Dried fruits and/or veggies
  • Pellets
  • Colorful extruded pieces
  • Hay

Muesli mixes were originally the food of choice for small pets such as rabbits, guinea pigs, and others due to their low cost, abundance in the marketplace, and the misconception that they are nutritionally appropriate for small pets.  As we have learned more about the nutritional needs of these small mammals, however, it has become clear that muesli mixes are far from what is best for our little companions.

What Role Does Food Play in the Health of Small Pets?

To understand where mixes fall short from a nutritional perspective, it’s important to first understand the role that foods play in the health of small pets. The primary purpose of your small pet’s food is to provide vital micronutrients in the form of essential vitamins and minerals while supporting gastrointestinal (GI) tract health with adequate fiber.

While much focus has been put on rabbits and guinea pigs when it comes to research into nutritional inadequacies and health dangers related to mixes, many of these same findings and principles apply to other herbivores such as chinchillas and degus as well as small omnivores including mice, rats, hamster, and gerbils.

Debunking Common Mix Myths

Many popular mix-based diets are marketed in a way that leads consumers to believe they are appropriate and even beneficial for the family pet.  Though many of these claims lack supporting evidence, it’s understandable why they would be perpetuated by influencers such as pet store employees, fellow members of online pet communities, and others. 

In this four-part series, we’ll examine some of the most prevalent claims regarding mix-based diets and provide the facts so that you can make an educated choice when choosing the right diet for your furry family member.

The Common Questions We Will Answer in the Series Include:

Part One: The Truth About Mixes and Ingredient Quality

  • Are Mixes Made of Higher Quality Ingredients Than Other Kinds of Foods on the Market?
  • Do Mixes Provide Complete, Balanced Nutrition for my Pet? 

Part Two: The Truth About Mixes and Foraging

  • Will Mixes Stimulate My Pet's Instinctual Foraging Behaviors?
  • Will Mixes Keep My Pet Active and Increase Time Spent Feeding? 
  • Are Foraging Blends Better for My Pet than other Mixes?

Part Three: The Truth About Mixes and Your Pet's Health 

  • Is There Evidence That Mixes Are Bad For My Small Pet?
  • Will Mixes Support My Pet's Health and Wellbeing? 

Part Four: The Truth About Mixes and Selective Feeding

  • Can't I Just Supplement My Pet's Mix With Other Healthy Foods?
  • Can't I Just Train My Pet to Not Selectively Feed? 

True or False: Mixes are of higher quality than other kinds of foods on the market.

FALSE: Most mixes are made with low-quality, inexpensive ingredients designed to keep costs down.  And, while the diversity of ingredients may look healthy and nutritious, the opposite is often true.

When it comes to mixes, the least expensive ingredients typically make up a larger proportion of the diet and, unfortunately, these components most often offer limited to no nutritional benefit to your pet. 

Examples of these inexpensive, non-functional ingredients include:

  • Ground corn
  • Peanuts
  • Raisins
  • Various dried fruits

Why Are These Ingredients Bad?

These inexpensive ingredients have no added micronutrients (i.e. vitamins and minerals) and tend to be higher in starch, fat, and sugar that can cause havoc on your pets’ digestive tract if not regulated.
They also often utilize artificial colors, flavors, and preservatives that offer no nutritional value and don’t belong in quality pet food.

Some companies may also cut costs by using food components from other species’ food lines. For example, the colorful extruded bits in your guinea pig or rabbit food may also be found in a bird food product from the same manufacturer.


True or False: Mixes provide complete, balanced nutrition for my pet.

FALSE: In most cases, the food left behind by pets offered a mix-based diet is the high fiber, vitamin and mineral fortified pellets. This has been shown in studies where rabbits selectively ate the majority of grains and extrudates (e.g. colorful extruded bits) when offered muesli diets and most often left the uniform pellets uneaten up to 68% of the time.5

What Happens When Pets Selectively Eat These Items?

Selective eating behaviors tied to mix-based diets can result in nutritional imbalances, including:

  • Inadequate fiber
  • Excessive starch and sugar
  • Vitamin deficiencies

The nutritional inadequacies of mixes have been documented in the past and several studies published by veterinarians and exotic animal experts specifically recommend against feeding mixes and/or advocate feeding uniform, homogenous pellets.


References

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  2. Lebas, F., P. Coudert, H. De Rochambeau, and R.G. Thébault. 1997. The Rabbit - Husbandry, Health and Production (2d edition) FAO publ., Rome, pg. 223.
  3. Mullan, S.M., and D.C.J. Main. 2006. Survey of the husbandry, health and welfare of 102 pet rabbits. Veterinary Record 159.4: 103-109.
  4. Meredith, A.L., J.L. Prebble, and D.J. Shaw. 2015. Impact of diet on incisor growth and attrition and the development of dental disease in pet rabbits. Journal of Small Animal Practice 56.6: 377-382.
  5. Prebble, J.L., and A.L. Meredith. 2014. Food and water intake and selective feeding in rabbits on four feeding regimes. Journal of Animal Physiology and Animal Nutrition 98.5: 991-1000.
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  8. Miller, G.R. 1968. Evidence for selective feeding on fertilized plots by red grouse, hares, and rabbits. The Journal of Wildlife Management: 849-853.
  9. Somers, N., B. D’Haese, B. Bossuyt, L. Lens, and M. Hoffmann. 2008. Food quality affects diet preference of rabbits: experimental evidence. Belgian Journal of Zoology 138.2: 170-176.
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  16. European Pet Food Industry Federation (FEDIAF), 2013: Nutritional Guidelines for Feeding Pet Rabbits. FEDIAF, Brussels (Belgium).
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