Health benefits of edible insects in pet food

A hot topic

Edible insects are a hot topic in academia and industry, attracting attention as a more ethical source of nutrients, more sustainable, and health-promoting for humans and animals. In the European Union, pets and aquatic animals can be fed with the black soldier fly larvae (BSFL), an exciting resource not just for food but also for pharmaceuticals.

Nutritional value

According to numerous analyses of their nutritional value, edible insects are an excellent source of proteins (up to 65% of dry matter in house crickets), essential amino acids, iron and zinc, and vitamins (B group, A, D, E, K). Their inferior quality of essential fatty acid composition could easily be improved by adding certain fatty acids, such as oleic or lauric acid, to insect feed.

The carbohydrates present in insects (6.71–15.98%) are primarily found in the insects’ outer skeleton, in the form of the polysaccharide chitin, the most abundant polysaccharide after cellulose. But what adds value to the edible insects is the bioactivity of these compounds, known for their protective effect on gut health and immunity. These effects provide an example of the fascinating emerging field of nutritional immunology.

Antimicrobial properties

Insects are a natural source of antimicrobial peptides (AMPs); ancient evolutionary weapons effective against bacteria, viruses, and fungi. AMPs that have already been determined and defined in BSFL are attacins, cecropins, defensins, diptericins, and knottin-like peptides. Naturally, the antimicrobial effect of BSFL extracts can not be attributed to AMPs only, since numerous other active compounds have yet to be determined.

Antimicrobial enzymes and proteins, essential for recognising and binding pathogens, have already been identified in BSFL. Chitin is an antimicrobial with a wide range of target microbes, but it also has  fat-reducing effects and it improves feed conversion in poultry. Dietary supplementation with chitin in farmed fish showed that chitin has antimicrobial, growth-promoting, antioxidant activity and immune- stimulation effects.

The deacetylated form of chitin, chitosan, is also known for its antimicrobial, antioxidant, antiulcer, wound healing, antihypertensive and hypolipidemic effects. Lauric acid found in BSFL is also gaining focus in nutrition and pharmacological studies since it has been found to have antimicrobial and immunomodulatory properties.

The research

The palatability and digestibility of dog and cat food based on edible insects have been investigated in many studies. However, only a few studies (with a limited number of animals) have investigated the health effects of edible insects in dogs. In one study, dogs were fed with roasted and ground cricket meal for 29 days and their blood tests came up in the reference range for healthy dogs. In another, a case series in 20 dogs with atopic dermatitis evaluated the effect of a new, commercially available insect protein-based dry food on the symptoms of food allergies and found some symptoms improved.

Clearly edible insects add value to pet food and potentially have plenty of health benefits. However, their health effects need to be studied better in companion animals – not just because the evidence is scarce, but also for the pleasure of gaining exciting, new knowledge about their actions.