By-products are often thought to be a low-quality pet food ingredient. But despite being a common ingredient, most people know very little about them and think they’re unhealthy or even harmful. Fortunately, the facts say something different!

When you consider the production process and nutritional value, it’s clear the assertion that “All by-products are bad,” is a myth.

The Facts About By-Products

Meat and poultry by-products can be an excellent source of protein and other nutrients, making it a beneficial ingredient in pet foods. Here’s the breakdown on by-products:

  • A by-product is any ingredient that is produced
 or left over when some other product or ingredient is made. 

  • Broths and gelatin are examples of meat by-products in human foods. 

  • By-products in pet foods that meet Association of American Feed Control Officials (AAFCO) guidelines come from clean animal parts other than meat, such as liver, kidneys and other organs.1
  • Purina purchases all by-products from USDA- inspected plants. They must meet stringent criteria for nutrient content, production and quality assurance.
  • By-products could be anything from liver, kidney to lungs. What they can’t be are feathers, hair, hooves, hide and intestinal contents.

Meat and poultry by-products can be more nutritious than meat alone.

Now you know what defines a by-product, but is it nutritious for your pet?

  • Muscle meat is deficient in many nutrients, including calcium, other minerals and vitamins. Many of these missing nutrients are abundant in meat by-products or poultry by-products.
  • By-products are also an excellent source of protein and amino acids.
  • For example, poultry by-product meal contains 60% to 70% protein and can be highly digestible.2

By-products are as good as the original product they come from, and Purina® products are made from high-quality ingredients that can boost the nutritional value of a pet food. Now that you know the facts, you can ignore the myths!

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1. "What Is in Pet Food." The Association of American Feed Control Officials Consumers. Web. 10 Oct. 2016.
2. Murray SM, et al. Raw and rendered animal by-products as ingredients in dog diets. J Nutr. 1998;128(12):2812S–2815S.