**Abstract**

Animal-origin food production presents an accelerated growth worldwide due to an increase in human demand. The aquaculture sector is one of the major players in terms of volume of animal protein production, and the availability of feedstuff to supply aquaculture feed (aquafeed) chain will be one of the main challenges for the next decades. Aquafeeds are mostly based on cereals, oilseeds, and marine-origin ingredients. The competition for feedstuff from the terrestrial animal industries such as pet, poultry, and swine challenges the profitability of aquafeeds, and complimentary ingredients need to be found. Many studies have focused on alternative protein sources, but the benefits of plant proteins, microorganisms-based, and diverse animal by-products are still under intense investigation to address some constraints including antinutritional factors and unbalanced nutrient profile. In this sense, the use of insects on the nutrition of aquatic animals could be an alternative. This chapter was elaborated to be an introductory reading for both academic and private sector and will discuss (i) the benefits of insects in animal nutrition, (ii) elucidate the nutritional aspects of different insect meals, (iii) bring some practical developments on aquatic nutrition, and finally (iv) discourse about constraints on insect use and its future perspectives.

**Keywords:** animal nutrition, alternative feedstuff, additives, lipid, protein, chitin

### **1. Introduction**

The demand for meat in 2050 will be 58% higher than the demand in 2010 [1], and revolutions in the form of animal protein production should happen to supply this demand; this will mean greater pressure on food resources especially on the ingredients for the formulation of rations [2]. In the quest for more sustainability in long-term animal production, the search for alternative ingredients is essential, since conventional ingredients such as soybean meal, wheat, corn, and animal meal have large price swings and exponentially high values years after years [2].

In this context, insect breeding is an alternative as a source of nutrients for animal feed and is a way to increase food and feed safety as an important source of protein [3]. In addition, insect breeding is considered a sustainable production, since these small animals feed on agroindustrial tailings, various organic wastes [3], and even inorganic ones [4].

The production of food of animal origin presents an accelerated growth in the world specially the chicken, swine, and cattle production [1]. These are produced with cereal and oilseed diets [2]. The nutrition of these animals requires high protein and energy levels that could be supplied by the use of insects. In addition, more than 1 million species of insects have been cataloged, and it is estimated that there are between 5 and 10 million, that is, only 10–20%, are known [5]; more than 1500 are used as food for about 3000 ethnic groups in more than 120 countries [6].

This scenario results in an emerging need for further studies to identify potential species to be produced and used in animal nutrition and as addressed by the FAO [7] as an alternative to traditional sources for human consumption. With these perspectives, it is exposed to the needs of recycling our ideas of human and animal feeding. In animal production, the mystification of this practice occurs more quickly, since many of the production animals, such as birds and fish, have the habit of feeding on insects.

#### **2. Insects in animal nutrition**

Agricultural production in the world faces many challenges to meet the growing demand for animal products, such as the demand for meat, which in 2050 will be 58% higher than the demand in 2010 [1]. Many studies have focused on new nutritional perspectives, but the benefits and weaknesses of vegetable protein sources and animal by-products are still under intense investigation. Ingredients of plant origin, for example, have several adverse effects on animal performance, attributable, among others, to antinutritional factors, inadequate profile of fatty acids, and amino acids [8, 9]. However, both are associated with environmental problems (e.g., exploitation of natural resources), economic (fluctuation of feed prices), or production (variation of quality and quantity) [10].

When considering the long-term sustainability of animal production, evaluations of alternative ingredients are essential because conventional ingredients, such as soybean meal and fishmeal [2], are raw materials that have been unstable due to the demand of other segments such as birds, swine, and pet [11]. Along with their derivatives and by-products, animal meal and soybean meal are two of the most widely used protein sources as feed ingredients. However, both are associated with environmental (e.g., exploitation of natural resources), economic (fluctuations in feed prices), or production (variation of quality and quantity) problems [10]. In this context, many studies have addressed new nutritional perspectives with alternative ingredients. However, the benefits and weaknesses of these sources are still the subject of intense research [11].

Supported by the problems mentioned above, it is necessary to search for alternatives. In this context, the use of insects could be a source of protein for animal feed. The commercial scale production of insects could guarantee a constant production in quantity, quality, and price. The use of this source to feed terrestrial animals and aquatic organisms already has some premises [7, 12] and brings, among others, the following advantages: (i) nutritional quality, (ii) noncompetition with food resources or land use, and (iii) use of "nutrients from residues" or "energy leftovers" from agro-food production as nutritional sources for insect growth. These small organisms can be grown in industrial plants and do not need large areas, especially when compared to other crops such as soybeans.

**121**

*cinerea*) [26].

nutrition of domestic animals.

*Insects in Aquaculture Nutrition: An Emerging Eco-Friendly Approach or Commercial Reality?*

feed conversion efficiency, and can feed on organic wastes [17].

The use of insects contributes to the natural recycling of nutrients and could be a source of high-quality animal protein derived from environmentally sustainable technology. In addition, a survey conducted in northern Italy showed that 90% of consumers would buy fish fed with insect meal [13]. This makes perfect chain fitting ("agriculture + fish + consumer") in addition to a more sustainable production call. In this item it is worth mentioning that some insects have the capacity to reduce the final biomass of residues in 50%, and specifically of nitrogen residues in 30–50%, and phosphorus in 61–70% [3, 14]. In other words, they convert organic residues into high-quality fertilizers in addition to forming "protein biomass" with admirable figures (~40% crude protein and ~ 30% lipid) [15, 16]. The arguments that reinforce its use would be that insects grow and reproduce easily, have high

In addition, studies have shown that it is technically feasible to produce largescale insects and use them as a sustainable protein alternative in the diet of birds, swine, cattle, and aquatic animals [12]. Once mass production of these small animals has been achieved, it would be possible to lower their cost and achieve economic viability in replacing traditional protein ingredients in animal feed [2]. Today the cost per kilo of the flour of some species of insects in the Brazilian market reaches more than US\$50.00/kg. In the literature we have some studies that used insects to feed fish such as house fly larvae (*Musca domestica*) as a source of protein for feeding tilapia and African catfish (*Clarias gariepinus*) [18–20]; larvae of butterflies (*Bematistes macaria*) for feeding African catfish hybrids (*Heteroclarias*) [21]; and *Tenebrio molitor* in the diet of African catfish [22], goldfish (*Sparus aurata*) [23], rainbow trout (*Oncorhynchus mykiss*) [24], European sea bass (*Dicentrarchus labrax*) [25], Nile tilapia (*Oreochromis niloticus*) [10], and cheap meal (*Nauphoeta* 

The larvae and pupae of the *Tenebrio molitor* beetle are promising options with several studies mainly for feeding fish and birds. This short-lived, easy-to-breed insect would be an alternative to temperate Western countries where this small animal is endemic [27]. Information on the breeding, feeding, and nutrient needs of this insect is already available in the literature [28, 29]. The larvae of *T. molitor* are omnivorous but are usually fed wheat flour or meal and supplemented with soybean meal, skimmed milk powder, or yeast [1]. The moisture in the feed seems to be fundamental for *T. molitor* because it can affect the productivity and fat content [30]. However, breeding of *T. molitor* larvae with resources such as wheat flour, soybean, and skimmed milk cannot be considered sustainable, since these products could be considered more suitable for direct consumption for humans or used in the

The larvae of *T. molitor* have the ability to recycle vegetable waste of low nutritional quality and turn them into high-quality food (biomass) [1]. Tea bag larvae were fed on food leftovers and turned this waste into a high-quality protein source, which reiterates the potential of tenacious larvae as a promising and sustainable alternative protein source [31]. In addition, it has been recently reported that this animal can even recycle plastics (**Figure 1**) because it has specific bacteria in its tract capable of degrading this material [4]. Thus, it would be possible to solve two major problems of the contemporary world: the scarcity of resources for human and animal food, besides the "biorecycle" of plastics. Another insect that has stood out with high potential for use in animal nutrition is the cinerea cockroach (*Nauphoeta cinerea*). Some companies in South America already produce it on a commercial scale to attend to zoos and feed rations mainly for birds. Due to its high protein content (approximately 60%), the demand for this flour has increased over the years. Some studies have demonstrated the potential of its use in fish diets [26].

*DOI: http://dx.doi.org/10.5772/intechopen.90489*

*Insects in Aquaculture Nutrition: An Emerging Eco-Friendly Approach or Commercial Reality? DOI: http://dx.doi.org/10.5772/intechopen.90489*

The use of insects contributes to the natural recycling of nutrients and could be a source of high-quality animal protein derived from environmentally sustainable technology. In addition, a survey conducted in northern Italy showed that 90% of consumers would buy fish fed with insect meal [13]. This makes perfect chain fitting ("agriculture + fish + consumer") in addition to a more sustainable production call. In this item it is worth mentioning that some insects have the capacity to reduce the final biomass of residues in 50%, and specifically of nitrogen residues in 30–50%, and phosphorus in 61–70% [3, 14]. In other words, they convert organic residues into high-quality fertilizers in addition to forming "protein biomass" with admirable figures (~40% crude protein and ~ 30% lipid) [15, 16]. The arguments that reinforce its use would be that insects grow and reproduce easily, have high feed conversion efficiency, and can feed on organic wastes [17].

In addition, studies have shown that it is technically feasible to produce largescale insects and use them as a sustainable protein alternative in the diet of birds, swine, cattle, and aquatic animals [12]. Once mass production of these small animals has been achieved, it would be possible to lower their cost and achieve economic viability in replacing traditional protein ingredients in animal feed [2]. Today the cost per kilo of the flour of some species of insects in the Brazilian market reaches more than US\$50.00/kg. In the literature we have some studies that used insects to feed fish such as house fly larvae (*Musca domestica*) as a source of protein for feeding tilapia and African catfish (*Clarias gariepinus*) [18–20]; larvae of butterflies (*Bematistes macaria*) for feeding African catfish hybrids (*Heteroclarias*) [21]; and *Tenebrio molitor* in the diet of African catfish [22], goldfish (*Sparus aurata*) [23], rainbow trout (*Oncorhynchus mykiss*) [24], European sea bass (*Dicentrarchus labrax*) [25], Nile tilapia (*Oreochromis niloticus*) [10], and cheap meal (*Nauphoeta cinerea*) [26].

The larvae and pupae of the *Tenebrio molitor* beetle are promising options with several studies mainly for feeding fish and birds. This short-lived, easy-to-breed insect would be an alternative to temperate Western countries where this small animal is endemic [27]. Information on the breeding, feeding, and nutrient needs of this insect is already available in the literature [28, 29]. The larvae of *T. molitor* are omnivorous but are usually fed wheat flour or meal and supplemented with soybean meal, skimmed milk powder, or yeast [1]. The moisture in the feed seems to be fundamental for *T. molitor* because it can affect the productivity and fat content [30]. However, breeding of *T. molitor* larvae with resources such as wheat flour, soybean, and skimmed milk cannot be considered sustainable, since these products could be considered more suitable for direct consumption for humans or used in the nutrition of domestic animals.

The larvae of *T. molitor* have the ability to recycle vegetable waste of low nutritional quality and turn them into high-quality food (biomass) [1]. Tea bag larvae were fed on food leftovers and turned this waste into a high-quality protein source, which reiterates the potential of tenacious larvae as a promising and sustainable alternative protein source [31]. In addition, it has been recently reported that this animal can even recycle plastics (**Figure 1**) because it has specific bacteria in its tract capable of degrading this material [4]. Thus, it would be possible to solve two major problems of the contemporary world: the scarcity of resources for human and animal food, besides the "biorecycle" of plastics. Another insect that has stood out with high potential for use in animal nutrition is the cinerea cockroach (*Nauphoeta cinerea*). Some companies in South America already produce it on a commercial scale to attend to zoos and feed rations mainly for birds. Due to its high protein content (approximately 60%), the demand for this flour has increased over the years. Some studies have demonstrated the potential of its use in fish diets [26].

*Emerging Technologies, Environment and Research for Sustainable Aquaculture*

and even inorganic ones [4].

of feeding on insects.

**2. Insects in animal nutrition**

production (variation of quality and quantity) [10].

still the subject of intense research [11].

of protein [3]. In addition, insect breeding is considered a sustainable production, since these small animals feed on agroindustrial tailings, various organic wastes [3],

The production of food of animal origin presents an accelerated growth in the world specially the chicken, swine, and cattle production [1]. These are produced with cereal and oilseed diets [2]. The nutrition of these animals requires high protein and energy levels that could be supplied by the use of insects. In addition, more than 1 million species of insects have been cataloged, and it is estimated that there are between 5 and 10 million, that is, only 10–20%, are known [5]; more than 1500 are used as food for about 3000 ethnic groups in more than 120 countries [6].

This scenario results in an emerging need for further studies to identify potential species to be produced and used in animal nutrition and as addressed by the FAO [7] as an alternative to traditional sources for human consumption. With these perspectives, it is exposed to the needs of recycling our ideas of human and animal feeding. In animal production, the mystification of this practice occurs more quickly, since many of the production animals, such as birds and fish, have the habit

Agricultural production in the world faces many challenges to meet the growing demand for animal products, such as the demand for meat, which in 2050 will be 58% higher than the demand in 2010 [1]. Many studies have focused on new nutritional perspectives, but the benefits and weaknesses of vegetable protein sources and animal by-products are still under intense investigation. Ingredients of plant origin, for example, have several adverse effects on animal performance, attributable, among others, to antinutritional factors, inadequate profile of fatty acids, and amino acids [8, 9]. However, both are associated with environmental problems (e.g., exploitation of natural resources), economic (fluctuation of feed prices), or

When considering the long-term sustainability of animal production, evaluations of alternative ingredients are essential because conventional ingredients, such as soybean meal and fishmeal [2], are raw materials that have been unstable due to the demand of other segments such as birds, swine, and pet [11]. Along with their derivatives and by-products, animal meal and soybean meal are two of the most widely used protein sources as feed ingredients. However, both are associated with environmental (e.g., exploitation of natural resources), economic (fluctuations in feed prices), or production (variation of quality and quantity) problems [10]. In this context, many studies have addressed new nutritional perspectives with alternative ingredients. However, the benefits and weaknesses of these sources are

Supported by the problems mentioned above, it is necessary to search for alternatives. In this context, the use of insects could be a source of protein for animal feed. The commercial scale production of insects could guarantee a constant production in quantity, quality, and price. The use of this source to feed terrestrial animals and aquatic organisms already has some premises [7, 12] and brings, among others, the following advantages: (i) nutritional quality, (ii) noncompetition with food resources or land use, and (iii) use of "nutrients from residues" or "energy leftovers" from agro-food production as nutritional sources for insect growth. These small organisms can be grown in industrial plants and do not need large

areas, especially when compared to other crops such as soybeans.

**120**

**Figure 1.**

*Adult and larvae of* Tenebrio molitor *(A) and feeding with plastic (B). Source: A, available at <plantascarnivoras.com.br> access 09/20/2016; B - [4].*
