Creature Companion 2018: September: 40-41.
Anton C. Beynen
In Europe, at least 12 insect-based, complete dry dog foods are marketed (Note 1). The first one
was launched in 2015 (1). The foods traceably contain preparations of black-soldier fly larvae or
yellow meal worms, but their ingredient lists often leave the insect species unnamed. All 12 foods
are positioned as hypoallergenic, while 8 of them also highlight insects’ sustainability. The array
comes along with one canned product and two dry cat foods.
Insects purportedly carry novel, previously uneaten protein which minimizes the risk to an
allergenic response. However, all petfoods unavoidably and legally have small amounts of insect
matter. Cats with outdoor access catch insects as prey. Treats with various insect species are
increasingly hitting the market. The efficacy of insect-based petfood in treating true food allergy is
unknown, but equally the condition is uncommon, implying little need for hypoallergenic foods (2).
Insect protein is claimed to be sustainable. In terms of global warming potential, the farming of
insects is less harmful than that of meat chickens, but more so than crop production. On average,
the 12 insect-based dry foods contain about 20% insect preparation, while 9 foods also contain
other animal-derived ingredients. Not only does complete vegetarian petfood (3) exclude meat-
animal exploitation, but it also is eco-friendlier than insect-based petfoods.
There is limited published information on insects as petfood component. Protein quality and
digestibility of black-soldier fly larvae and yellow meal worms are adequate. Foods with the insect
sources are consumed willingly. Short-term feeding tests did not elicit negative effects on visible
health of dogs and cats. Apparently, practical use of insect-based foods is without adverse events,
but long-term safety awaits confirmation.
Whole larvae of the black-soldier fly (Hermetia illucens) and the yellow-mealworm beetle (Tenebrio
molitor), or BSFL and YMW for short, have variable compositions. The crude protein and fat contents
are 41 to 56 and 15 to 36 % in the dry matter (4-9). For puppies and kittens, the sum of methionine
and cystine reflects the limiting amino acid in the two larvae species (6, 7). Lauric acid (C12:0)
represents about 40% of total fatty acids in BSFL (5), but less than 0.2% in YMW (4).
Analysis of dried and partially defatted BSFL and YMW preparations used as petfood ingredients
reveals around 60% crude protein, 15% crude fat and 10% crude fiber, but between-batch variation
is considerable. Roughly half of the crude-fiber analyte could constitute chitin (5), but the N-
acetylglucosamine polymer contributes little to the crude protein value.
In-vitro digestibility of protein in whole BSFL and YMW was 88.7 and 91.9% (6, 9), while the
undigested residue appeared poorly fermentable by dog feces as microbiota source (9). Feces of
dogs fed a BSFL-containing diet had increased chitin concentrations (10). For extruded foods with
partially defatted BSFL or YMW, each accounting for about 30% of total dietary protein, apparent
digestibilities of crude protein were 83.9 and 83.6% of intake in dogs and 79.8 and 80.4% in cats (11).
When dogs (12, 13) and cats (14) were switched to a formula with YMW as almost exclusive protein
source, the owners did not note changes in feces consistency. For dogs fed commercial dry foods
based on either lamb meal or BSFL, fecal scores differed statistically, but not meaningfully (10).
Free-ranging wolves (15) and feral cats (16) consume insects, the latter on average 1 weight% of
their diet. Insects not only make up almost 1% of the animals brought home by British domestic cats
(17), but are eaten also (18). Dogs seem to enjoy eating live BSFL (19) and dried mealworms (20) and
were equally attracted towards olfactory cues from either commercial dry food, dried whole BSFL or
YMW (21). In two-bowl preference tests, the intake ratio of dry foods with BSFL or YMW was about
60:40 in dogs and 40:60 in cats (11). Changing over dogs and cats to BSFL- or YMW-based, dry foods
went smoothly (11, 12-14).
Forty six out of 50 pet owners gave positive feedback after learning they had been feeding an insect-
based diet. Negative feelings, due to insect phobia and safety concerns, would be dropped for
veterinary-prescribed diets with insects (22). Veterinarians seem interested in insect-based food as
hypoallergenic alternative (23).
Insect-based, complete petfoods are on the market for up to three years. So far no health risks have
been reported. YMW- and BSFL-containing diets did not negatively affect apparent pet health in
studies lasting 28 (12-14) or 42 days (10), but clinical chemistry measurements were not done. An
oral dose of 2.5 g cricket powder/kg bodyweight did not produce adverse effects in dogs (24). The
impact of insect consumption on health in the long term is unknown. Insects might hold toxicants,
either self-synthesized or derived from their feed substrates.
When at the farm gate, YMW (25) and BSFL (26) have emitted less greenhouse gas per kg live weight
than chicken, pork or beef (27), but more than one kg of corn (28) or soybean (29) (Note 2). The
ranking could persist after the processing toward isonitrogenous, dry protein concentrates for use as
petfood ingredients. However, fair comparisons require calculations that allow not only for
transportation and processing, but also for land use (change), energy efficiency, water pollution, co-
products and their applications.
Overview of insect-based, complete dry dog foods
Natural Dog Food
Insect & Lecker
Dog Sana Hermetia^
^Marketed as veterinary diets
Insect = insect species as ingredient; information is based on brochures, websites, articles and, in
two cases*, personal communication. 1-12 = insect description in ingredient list; BSFL = black-soldier
fly larvae; YMW = yellow mealworms; % I = declared percentage of insect ingredient; nd = not
declared; Hypo = hypoallergenic claim; Sust = sustainability claim; Anim = declared animal
ingredient(s) other than insect; a-i = description of the animal ingredient(s); % CP = declared
percentage of crude protein
1, insect meal; 2, insect protein; 3, dehydrated insect; 4, insects; 5, insects; 6, Hermetia illucens; 7,
dried insects; 8, insect protein; 9, protein-rich insect meal (Hermetia illucens); 10, insect protein
from Hermetia larvae; 11, insects (protein meal Hermetia illucens); 12, Hermetia illucens meal
a, poultry fat, fish oil; b, animal fats, hydrolysed pork liver; c, poultry fat, fish oil, hydrolysed chicken
liver; d, animal fats, salmon oil; e, animal fats, salmon oil; f, animal fat, salmon oil; g, salmon oil; h,
mussel flesh meal; i, oils and fats (the latter presumably is animal-derived)
Global warming potential (GWP) is an index of the amount of heat trapped by greenhouse gasses
(CO2, NO2, CH4) in the atmosphere. GWP is expressed as kg CO2-equivalents (eq) per kg of product
during its life cycle. The table lists the calculated GWPs of partly and conditionally interchangeable
ingredients for dry petfood
soldier fly larvae
~GWP as is (live/fresh weight) values are derived from the references. GWP refers to soybean
produced in Latin America and exported to Europe, without considering land-use change
(deforestation); + Cradle-to-farm gate GWP
√DM = dry matter; *GWP/kg dry product = 100/%DM x GWP as is. For the meaty products, GWP dry
values concern the halfway points of ranges for GWP as is.
^CP = crude protein in DM. ªGWP/kg protein = 100/%CP x GWP dry
# Based on data in Ref 26. BSFL contained 42% protein and 35% fat in DM. GWP for protein = 2.1 kg
CO2 eq/kg. GWP for fat = 2.9 kg CO2 eq/kg. BSF were grown on food waste for which transportation
was taken into account, but not production. For YMW, 56% of the GWP related to production and
transport of feed (25). Noteworthily, in the European Union, waste streams such as catering
leftovers and manure are prohibited as feedstuffs for insects.
For the production of dry petfood, defatted, dry meals are the main protein carriers. Thus, the
environmental impact of the 7 products in the table should be compared after they have been
processed toward isonitrogenous, dry protein concentrates. However, such comparison is not
straightforward as many factors play a role (30, 31). For instance, calculated greenhouse emission
for South American soybean growing is much greater when associated deforestation is taken into
account (29). Rendered animal protein meals in petfood are derived from slaughter byproducts. In
this respect, economic allocation is commonly employed (27). In doing so, the total environmental
impact is redistributed between the co-products based on their relative economic values.
Concerning slaughter meats and by-products, that approach is debatable (32).
1. Van Os W. Insecten als grondstof in kattenvoeding. Dier-en-Arts 2017; Nr 8/9: 240-241.
2. Beynen AC. Hypoallergenic dog foods: supply and demand overwhelm need. All About Feed 2015;
23/9: 34. DOI: 10.13140/RG.2.2.24643.30248
3. Beynen AC. Vegetarian petfoods. Creature Companion 2015; February: 50-51.
4. Finke MD. Complete nutrient composition of commercially raised invertebrates used as food for
insectivores. Zoo Biol 2002; 21: 269-285.
5. Finke MD. Complete nutrient content of four species of feeder insects. Zoo Biol 2013; 32: 27-36.
6. Bosch G, Zhang S, Ooninx DGAB, Hendriks WH. Protein quality of insects as potential ingredients
for dog and cat foods. J Nutr Sci 2014; 3: e29.
7. McCusker S, Buff PR, Yu Z, Fascetti AJ. Amino acid content of selected plant, algae and insect
species: a search for alternative protein sources for use in pet foods. J Nutr Sci 2014; 3: e39.
8. Makkar HPS, Tran G, Heuzé V, Ankers P. State-of-the-art on use of insects as animal feed. Anim
Feed Sci Technol 2014; 197: 1-33.
9. Bosch G, Vervoort JJM, Hendriks WH. In vitro digestibility and fermentability of selected insects for
dog foods. Anim Feed Sci Technol 2016; 221: 174-184.
10. Kröger S, Heide C, Zentek J. Influence of proteins from the Black Soldier Fly (Hermetia illucens) on
nutrient digestibility and faecal and immunological parameters in dogs. Proceedings 21st European
Society of Veterinary and Comparative Nutrition Congress, Cirencester, 2017, p 102.
11. Vobra Special Petfoods, Evaluatie van insectenbronnen in Sanimed Intestinal. Intern verslag,
12. Leriche I, Fournel S, Chala V. Assessment of the digestive tolerance in dogs of a new diet based
on insects as the protein source. Proceedings 21st European Society of Veterinary and Comparative
Nutrition Congress, Cirencester, 2017, p 103.
13. Leriche I. Assessment of the palatability and digestive tolerance in dogs of a new diet based on
insect as the protein source. Proceedings Insectinov 2, Paris, 2017, p 36.
14. Leriche I, Fournel S, Chala V. Assessment of the digestive tolerance in cats of a new diet based on
insects as the protein source. J Feline Med Surg 2017; 19: 965.
15. Bosch G, Hagen-Plantinga EA, Hendriks WH. Dietary nutrient profiles of wild wolves: insights for
optimal dog nutrition? Br J Nutr 2015; 113: S40-S54.
16. Plantinga EA, Bosch G, Hendriks WH. Estimation of the nutrient profile of free-roaming feral cats:
possible implications for nutrition of domestic cats. Br J Nutr 2011; 106: S35-S48.
17. Woods M, McDonald R, Harris S. Predation of wildlife by domestic cats Felis catus in Great
Britain. Mammal Rev 2003; 33: 174-188.
18. Krauze-Gryz D, Gryz J, Goszczyński J. Predation by domestic cats in rural areas of central Poland:
an assessment based on two methods. J Zool 2012; 288: 260-266.
19. Dogs eat live BSFL! https://www.youtube.com/watch?v=8PmhY4j9XY8
20. Mealworm dog food https://www.youtube.com/watch?v=kXMIKoWs6aI
21. Kierończyk B, Rawski M, Pawełczyk P, Różyńska J, Golusik J, Józefiak D. Do insects smell attractive
to dogs? A comparison of dog reactions to insects and commercial feed aromas – a preliminary
study. Ann Anim Sci DOI: 10.2478/aoas-2018-0012
22. Leriche I, Chala V, Ereau C. Pet owners’ perception of insects as a protein source for cats and
dogs. Proceedings XI Southern European Veterinary Conference, Barcelona, 2017 (2 pages)
23. Pagani E, Russo N, Schiavone A, Prola L. Veterinary practitioners perception of insects as protein
source for pets. Proceedings 20th European Society of Veterinary and Comparative Nutrition
Congress, Berlin, 2016, p 194.
24. Ryu HY, Lee S, Ahn KS, Kim HJ, Lee SS, Ko HJ, Lee JK, Cho M-H, Ahn MY, Kim EM, Lim JH, Song KS.
Oral toxicity study and skin sensitization test of a cricket. Toxicol Res 2016; 32: 159-173.
25. Oonincx DGAB, De Boer IJM. Environmental impact of the production of mealworms as a protein
source for humans – A life cycle assessment. Plos One 2012; 7: e51145.
26. Salomone R, Saija G, Mondello G, Giannetto A, Fasulo S, Savastano D. Environmental impact of
food waste bioconversion by insects: Application of life cycle assessment to process using Hermetia
illucens. J Clean Prod 2017; 140: 890-905.
27. De Vries M, De Boer IJM. Comparing environmental impacts for livestock products: A review of
life cycle assessments. Livest Sci 2010; 128: 1-11.
28. Kim S, Dale BE, Jenkins R. Life cycle assessment of corn grain and corn stover in the United
States. Int J Life Cycle Assess 2009; 14: 160-174.
29. Castanheira ÉG, Freire F. Greenhouse gas assessment of soybean production: implications of land
use change and different cultivation systems. J Clean Prod 2013; 54: 49-60.
30. Van Huis A, Oonincx DGAB. The environmental sustainability of insects as food and feed. Agron
Sustain Dev 2017; 37: 43.
31. Halloran A, Hansen HH, Jensen LS, Bruun S. Comparing environmental impacts from insects for
feed and food as an alternative to animal production. In: Edible Insects in Sustainable Food Systems.
Springer International Publishing AG, part of Springer Nature 2018, pp 163-180.
32. Beynen AC. Green petfoods. Creature Companion 2015; March: 54-55.