There's a fly in my kibble! Insect-based pet food takes off

Rise of protein alternative raises questions about nutritional value, long-term safety

March 16, 2020 (published)
By Ross Kelly

EnviroFlight photo
A dog appears unfazed about eating dried black soldier fly larvae.

Apparently, dog food made from the larvae of black soldier flies tastes like a combination of beef and cheese. But if humans want to brave sampling it, an accompanying glass of wine might help to get it down.

So says Will Bisset, sales and innovation director of Yora Pet Foods, a British startup at the crest of the world's nascent insect-based animal feed movement.

"Dogs absolutely love it," Bisset claims of Yora's bug-based kibble, which he guinea-pigged on himself, too, during its five-year development.

His adventurousness is paying off. Yora started selling its dog food in January 2019 and is doing a howling trade, having notched sales of just over £1.0 million (US$1.2 million) in its first financial year of operation.

It is among several companies dabbling in a novel food space that is attracting increasing attention from pet owners, regulators, financiers and the veterinary profession.

Their business cases aren't grounded so much on palatability as they are on green appeal. Hungry dogs and cats account for 25-30% of the environmental impacts from all animal production in the United States, in terms of land, water, fossil fuel, phosphate and biocides use, according to a study by Gregory S. Okin, a professor in the UCLA Institute of the Environment and Sustainability.

The idea is that using insects as an alternative protein source potentially could shrink that environmental footprint significantly. Research published in 2017 by scientists at Wageningen University in the Netherlands suggests that insect farming requires less land and water than livestock production and results in lower greenhouse gas emissions. Yora claims insect farming needs just 2% of the land required to farm cattle to produce 10 kilograms of protein, while generating about 4% of the emissions.

EnviroFlight photo
Larvae of the black soldier fly, pictured in its adult form, is starting to be incorporated in pet food as an alternative protein source that is touted as environmentally friendly.

The sustainability case hasn't been lost on financiers. France's Ÿnsect, an agri-tech company breeding mealworm from beetles for fish feed, crop fertilizers and pet food, last year raised $125 million. The private funding round was led by London-based investor Astanor Ventures and marked the biggest single haul in the sector to date. Other players include the Dutch group Protix, which supplies black soldier fly larvae to Yora, and the Anglo-South African company AgriProtein.

In North America, the industry is represented by the likes of EnviroFlight of Yellow Springs, Ohio; Beta Hatch of Seattle, Washington; and Enterra Feed of Langley, British Columbia.

Big traditional pet food players are watching closely. "Insect-based proteins have the potential to be sustainable, nutritious protein sources," Dr. Jo Gale, Mars Petcare senior manager of global science advocacy corporate affairs, told the VIN News Service. Mars is the world's biggest pet food manufacturer by sales.

"While the industry is in its early stages, we believe that exploring these types of alternative ingredients and technologies could allow us to work to improve the future of pet nutrition," Gale said.

EnviroFlight's vice president for sales and marketing, Carrie Kuball, said growth has been "exponential." But she acknowledged that the industry is still finding its feet, using the early days of chicken farming as an analogy.

"We know how to breed, hatch, grow, and process the larvae," she told VIN News via email. "But now we need to perfect the process."

She added: "There is so much that is still unknown about this industry."

Veterinarians and regulators around the world are grappling with questions about the nutritional value and safety of insects. The unknowns have acted as a brake on companies wanting to rapidly scale up production to lower costs and make their wares more financially palatable to consumers.

In recent years, however, food regulators in Europe and the United States have started warming to insects, as the scientific evidence gets more supportive and concerns intensify about the environmental impact of land clearing.

A breakthrough in the U.S. came in 2016, when its Food and Drug Administration allowed the use of black soldier fly larvae in diets for salmonoid fish. Similar approvals followed in 2018 and 2020 for poultry and swine, respectively.
U.S. regulators have not permitted the use of insect-based ingredients in pet food to date. However, some insect-derived treats are on the market, as manufacturers have the latitude to legally add ingredients that haven't yet received official approval.

The FDA establishes regulations alongside the industry standard-setter known as the Association of American Feed Control Officials. AAFCO is a voluntary membership association of local, state and federal agencies. Its executive director, Sue Hays, told VIN News that AAFCO is waiting on proponents of insect-based pet food to provide sufficient information to its investigators to trigger an official "ingredient definition process" in the U.S.

The pet food producers themselves must conduct safety studies for an intended use in an intended species. "This is where the black soldier fly larvae companies are right now," Hays said via email.

In Europe, regulators in 2017 allowed insect-based protein to be used in aquaculture, having previously banned all animal-based proteins in agricultural feed to prevent the spread of bovine spongiform encephalopathy, otherwise known as mad cow disease.

Insect use in pet food long has been allowed in Europe. But until Yora appeared on the scene last year, bugs typically had been fed to exotic pets such as ornamental birds and reptiles by owners willing to pay a premium for live feed. The lifting in 2017 of restrictions on fish feed could encourage the production of more dog and cat food in Europe as agribusinesses such as Ÿnsect eye the pet market as a lucrative side business.

Are cockroaches as nourishing as chickens?

Yora and EnviroFlight both claim their products not only are irresistible to dogs but contain just as much protein as traditional sources such as poultry meal and fish meal, and are equally as digestible. There is some independent scientific research to back those claims.

A study published in 2016 by animal nutritionists at Wageningen University found the protein quality of black soldier fly larvae was "high," based on its amino acid profile and digestibility.

An earlier study by the same team, published in 2014, found the protein content of a wide array of insects, including crickets and even cockroaches, generally was higher than that of soybean meal and close to that of poultry meal and fish meal.

In an interview with VIN News, one of the study authors, Guido Bosch, said pet companies often "over-formulate" their food, in any case. That means they add more protein than is necessary, as a buffer against uncertainties such as different digestive capacities among dogs, and to satisfy consumer tastes for high-protein products.

"Insect species all differ, of course, in digestibility, and they differ a bit in amino acid content," he said. "But I think they are all fit for use in pet food, from a nutritional standpoint."

Black soldier fly larvae and mealworms have emerged as the most popular insect-based feed stocks for animal food because they are easy to scale and can be fed low-cost agricultural byproducts, such as potato pulp and wheat starch.

And they have uses that go beyond the purported environmental benefits. Bug-based proteins might provide an alternative food source for animals allergic to more traditional protein sources, such as beef, Bosch said.

They are also rich in fats, while their feces — known as frass — makes for a handy fertilizer, notes Mark Finke, a pet food nutrition consultant who has advanced degrees in both nutrition and entomology and who has published extensively on this field.

The fat of black soldier fly larvae is notably rich in lauric acid, a saturated fatty acid found in various plant and animal fats and oils, including coconut oil and palm kernel oil, and believed to have antimicrobial properties. A paper published Jan. 31 in the journal British Poultry Science found that black soldier fly larvae could replace soybean meal in turkey feed without negatively affecting growth, nutrient digestibility, or quality of breast and thigh muscle. The researchers also found that replacing soy oil with the fly larvae fat reduced proliferation of potentially pathogenic bacteria and levels of inflammatory proteins in the turkeys. They wrote: "Black soldier fly larvae fat may be considered an antimicrobial agent and support immune responses."

If the finding is borne out, it could be a big deal because regulators around the world are trying to limit the use of antibiotics to combat the development of resistance in pathogens to drugs used by humans and other animals.

But insects aren't a miracle food. They have potential drawbacks.

One, Finke said, is that insects can be low in calcium because they don't have bones, though calcium levels may vary between species and even within the same species, depending on their diet. "Black soldier flies specifically can be really high in calcium or really, really low," Finke told VIN News in an interview. "It's kind of a buyer-beware scenario." At the same time, he said, many traditional protein sources such as poultry and meat meals contain more calcium than is needed by dogs. One solution might be to mix low-calcium insect meal with other protein sources containing high calcium to optimize the levels in the pet food.

Like any source of animal protein, contamination also is a risk factor. Insects can be vectors of a variety of pathogens, or absorb metal and chemical pollution, including pesticides. "Insect meals are heat-processed already, so in that sense, they are sanitized," Bosch said. "But you need to be sure of what you're bringing into the factory." Black soldier flies, Finke notes, especially are apt to accumulate heavy metals from their feed, particularly cadmium and lead.

There also are long-term health risks to consider. Bosch and Finke both believe the industry could benefit from conducting months-long or even years-long feeding studies to prove the safety of their products. "These types of studies are quite important for these novel diets, not only for insects but also for the grain-free diets," Bosch said. "We don't really know to what extent these diets are nutritional over the long term."

His reference to grain-free diets alludes to an issue under investigation by the FDA involving a recent spike in dogs of a heart condition, dilated cardiomyopathy, and the food they eat. A common thread in many cases is a diet described as "grain-free" and containing exotic proteins; and/or legumes such as peas, lentils and chickpeas; and/or potatoes.

Given the potential for novel ingredients and new formulations to raise health issues over time, Finke said it is reasonable to ask pet food makers to demonstrate safety. "Veterinarians, I think, should ask questions," he said. "I would go to the manufacturer and I would say, 'What feeding trials do you have to show that this is safe in a long-term situation?' "

"Whenever we get too far outside places that we've got 10, 20, 30 years of experience making pet food, shouldn't we be asking the pet? So at a minimum, feed it to them using AAFCO feeding trials. Give them physicals. Do blood work. Make sure these dogs are healthy at the beginning and the end of the trial."

Swatting disease and contamination risks

Veterinary nutritionists contacted by VIN News were cautiously supportive of the foray into the use of insect proteins.

"A claim for a complete food in Europe can be based on computer formulation alone," Dr. Marge Chandler, a consultant in small animal nutrition at Vets Now Referrals in Glasgow, Scotland, noted by email. "[There is] lots of potential but we need more studies, including some longer-term feeding trials to feel confident to make recommendations."

Dr. Joe Bartges, a professor of medicine and nutrition at the University of Georgia's College of Veterinary Medicine in the U.S. said: "Use of insects as a source of protein should be acceptable — as is chicken feathers or other protein sources — as long as the diet is rounded out to be complete and balanced."

He added: "Insect-based food is not complete and balanced by itself — but no foodstuff is."

EnviroFlight's Kuball points out that insects are a natural part of the diet of the ancestors of domesticated dogs and cats. And she notes that many pet dogs and cats regularly eat insects they find outside or in their houses.

To earn an AAFCO-approved "definition" and actually start selling insect meal in the U.S, pet food manufacturers must do at least one of two things. They can either formulate their diets to meet "minimum acceptable" nutrient levels for cats and dogs at several life stages; or they can run feeding trials to demonstrate that their diets meet the needs of the species for which they are intended.

Feeding trials can be expensive, possibly prohibitively so for small companies that lack the financial firepower of established players such as Mars Petcare or Nestle Purina.

Kuball at EnviroFlight said feeding trials also can be made impractical by "the inherent variability in pet care and management in the home, and the vast number of pet breeds along with their unique nutritional and veterinary needs that would have to be considered."

Yora isn't doing a formal feeding trial but Bisset said they're monitoring "several" dogs and taking blood samples "at intervals throughout their lives." The dog fed Yora's food the longest has been on it for two years and is "doing very well indeed," he said.

Bisset added: "We have sold well over 50,000 bags and haven't had any issues reported with many dogs being on the food for well over a year. We constantly have informal monitoring by the very people who use our products and we are fully confident in the high quality nutrition that we offer." Yora claims that its food constitutes a complete diet. Besides the insect-based protein, it contains oats, potato, maize, peas, yeast, minerals, vitamins and glucosamine, among other ingredients.

How long it will take for companies to gain approval to sell insect-based pet food in the U.S. is unclear. Hays said AAFCO intentionally moves slowly to allow stakeholders to learn of, and respond to, any issues being addressed. "It can take a couple of years for a company to work through a definition to the point where the members (states) vote on it at a meeting and the states indicate their acceptance of the ingredient," Hayes said.

As for disease and toxicant risks, Kuball said EnviroFlight feeds only AAFCO-defined ingredients to its larvae to mitigate against contamination. Further, the larvae's diet is formulated so the company knows what they are getting on any given day. "We monitor finished product closely by testing nutrient and microbial specs and holding product until all results are back before selling the ingredients," she added.

Yora also tests its product and feeds its larvae exclusively fruit and vegetable byproducts to minimize disease risks, Bisset said, that are just as prevalent, if not more so, in meat-based proteins. Yora also takes the extra step, Bisset said, to have larvae chilled slowly so they are in hibernation and unconscious, in order to rule out suffering, before they're manufactured into food.

"People might imagine dirty grubs but these guys only eat vegetable and fruit byproduct in an £18m state-of-the-art farm," he said.

The result is an expensive bag of dog chow. Yora currently charges £13.99 for a 1.5 kilogram bag of kibble (US$17 for 3.3 pounds), about a week's supply for a big dog and maybe a couple or more for a small one. The price rises to £47.99 for six kilograms and £89.99 for 12 kilograms (US$59 for 13 pounds and US$110 for 26.5 pounds).

By comparison, a quick look on Amazon shows you can buy a 15-kilogram bag of traditional dry dog food in the U.K for under £20.00 (33-pound bag for US$24.50).

If the insect-protein diets prove successful and popular, presumably costs would come down as the industry enlarges.

Yora already is poised to branch out, with a cat food under development, Bisset said. And after cats, he says, the final frontier could be us.

"I think a gateway is pets," Bisset said. "As people get more used to it, they'll start eating it themselves."

Correction: This story has been changed to correct a statement on when the FDA began allowing the use of black soldier fly larvae in animal diets, and for what animal categories. The story also has been changed to clarify the regulatory and legal status of insect-based ingredients in pet treats.

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