by Bénédicte Lorrette – PhD, Animal Nutrition & Health R&D Director, Ynsect
Insect protein is one of several novel protein sources that are raising interest among pet-owners who are seeking alternatives to conventional meat-based petfoods. This interest in alternatives is in part motivated by their perceived nutritional and environmental benefits. Ÿnsect’s ingredient, WetPro15, certainly meets these criteria: the mealworm pulp has a higher protein-to-fat ratio than proximate products such as MDMs (mechanically deboned meat); it is a natural source of linoleic and oleic acids; and its ileal and peptic digestibility are greater than 90 percent. From an environmental standpoint, its climate change contribution is equivalent to chicken MDM, and significantly lower than other meat-based protein sources.
However, while pet-owners are increasingly evaluating products based on their nutritional and environmental profile, there are other factors that contribute to their choice of their pets’ diet. One of these is how much enjoyment the pet derives from its food: a recent study has reported that palatability is the fourth-most important aspect of a pet food (out of fourteen attributes surveyed) that pet-owners consider when choosing their companions’ diet and it is moreover considered an aspect of animal welfare, coming under Provision five which mandates for ‘positive mental experiences’.
Palatability and digestibility
Palatability, which encompasses visual, olfactory and textural cues in addition to taste per se, appears to be particularly important for cats, which show greater selectivity than dogs. It is therefore important that any novel ingredient should undergo palatability trials. Here, we report on a preliminary trial conducted by an external partner that reveals that incorporating this product into a poultry-based paté does not diminish the palatability of the food.
Another factor that is of particular concern to dog-owners is the digestibility of the food – specifically regarding how it affects the dogs’ faecal characteristics. We have previously reported results of a safety trial of our dry petfood ingredient, Protein70, which showed that dogs’ stool quality scored an ideal score of three – ‘moist and formed’. Here, we report on a new trial in which we confirm similar results for WetPro15.
Palatability trial on cats
To evaluate the palatability of WetPro15, we carried out a two-bowl test in which 33 cats were offered a choice between a control paté, whose animal protein source was poultry MDM, and a test paté, in which 40 percent of the animal protein source was replaced with WetPro15. As shown in Figure 1, there was no significant difference in intake ratio (one-tailed t-test at 95 percent confidence), meaning the cats were as eager to consume the test diet as the control diet. Moreover, cats chose the test paté first 59 percent of the time, which indicates that visual and olfactory cues were positive.
Palatability & faecal consistency in dogs
Our dog trial was performed via a 10-day monadic test in which 32 adult dogs were either fed a control paté (poultry MDM 50 percent) for five days followed by a test paté (20 percent WetPro15 & 30 percent poultry MDM) for five days, or vice versa. As shown in Figure 2a, there was no significant difference in intake quantity – a total of 309 g of test paté (blue) was consumed, compared to 288 g of control paté — indicating that the insect protein was no deterrent to consumption.
The dog owners were asked to report on aspects related to the digestibility of the diet, including the firmness and quantity of the dogs’ faeces (figure 2b). The diet including the test product was associated with ‘just right’ faecal consistency by 81 percent of owners, compared to only 63 percent for the control diet. Moreover, 22 percent of owners reported increased flatulence after the control diet, compared to only six percent after the test diet.
When owners were also asked to judge their pets’ enjoyment of the food, 75 percent reported a high level of enjoyment from the test paté, compared to only 63 percent from the control paté. Overall, 28 percent of dogs were reported to prefer the test paté compared to only 13 percent preferring the control (Figure 2c); nearly 60 percent showed no preference.
Moving forward
While further studies are required to determine the significance of these observations, they certainly suggest that at the very least, the presence of WetPro15 was no deterrent to either cats or dogs, in terms of the palatability of the food and to dogs’ enjoyment of their food.
Besides, the canine trial suggests further that a diet including mealworm protein has digestive benefits for dogs. This is probably related to the presence of chitin in the mealworm pulp, which is known to be a good source of natural fibre.
The palatability of insect-based petfoods is perhaps unsurprising, in principle, considering that catching and consuming insects (among other prey) is a natural behaviour for both dogs and cats. In comparison to conventional wet petfood products, our product has no obvious visual or olfactory deterrents: the mealworm pulp’s light brown colour makes it visually similar to traditional products, and it is not associated with any strong odour. Moreover, as previously reported in our article, it is texturally similar to patés made from chicken MDM. Hence, from the perspective of the animal, including our product in the diet appears to be largely transparent: mealtime for them is ‘business as usual’.
These initial results are an encouraging indication for pet-owners that they can offer their companions a diet that is both nutritionally and environmentally superior, without sacrificing their tastebuds.
