Insect Meal: A Sustainable Alternative Protein Source for Poultry Birds
Dr. Prajna Mohapatra
Assistant Professor, Department of Animal Nutrition, Institute of Veterinary Science and Animal Husbandry, Siksha O Anusandhan Deemed to be University, Bhubaneswar, Odisha.
Corresponding Author: PRAJNA MOHAPATRA
Email id: prajnamohapatra28@gmail.com
ORCID ID: 0000-0001-5700-0448
Abstract: Insects are the natural diets for the free-ranging poultry birds. Hence, insect meal can be a sustainable alternative protein source for poultry. The nutritional value of the insect meals is excellent as they are enriched with high-quality protein, a balanced essential amino acid profile, fatty acids, vitamins, minerals, and antimicrobial peptides. Some commonly used insects as meals in poultry diets are; house fly larvae, black soldier fly larvae, mealworms, grasshoppers, house crickets, locusts, silkworms, and earthworms. The digestibility and palatability of insect meals are very promising in improving the performance and meat quality of poultry birds.
Keywords: Insects, Proteins, Essential Amino Acids, House Fly, Black Soldier Fly
Introduction
The total feed cost in poultry production takes a share of approximately 70% of the total production cost (FAO, 2011). This share of feed cost acts as a huge barrier to sustainable and profitable poultry production. The high feed cost is due to the scarcity and low supply of feed resources. Furthermore, the high nutritional requirements of the poultry birds and the low profit margin are the major reasons for the search for alternative feed ingredients with high nutritional value to replace the conventional ingredients, without affecting health and performance.
Use of insects in poultry nutrition
High-quality protein in the diet is a must for livestock animals, especially monogastric animals and birds for meat production. The high-quality protein sources must contain, a well-balanced essential amino acid profile, high digestibility and palatability that lacks any antinutritional factors. Amongst the alternative protein sources, insects have arised as a preferable and cost-effective option in recent times (Cullere et al., 2018).
Insect Meal
Insects are one of the most preferable natural diets for chickens (Bovera et al., 2015). On that account, insect meal can be a sustainable alternative protein source for poultry. Insect meals mostly derived from larval stages are used in poultry diets (Chia et al., 2019). Various forms of insect meals such as live, dried, or paste can be used as poultry diets. Common house fly larvae, black soldier fly larvae, mealworms, grasshoppers, house crickets, locusts, silkworms, and earthworms are some of the most frequently used insect meals.
Nutritional Value:
According to the natural feeding patterns, dietary habits, and developmental stages of the insects, the nutrient content also varies. But, commonly, insect meals are rich sources of protein, energy, essential amino acids, various saturated and unsaturated fatty acids, vitamins, and minerals. Insects contain carbohydrates in two forms i.e. chitin and glycogen. Chitin is mainly present in the exoskeleton. It contributes to improving the immune system of chickens. Glycogen is present in the muscle cells. The protein content of insect meals ranges from 40%- 60%. Some species of insects may contain a protein level as high as 77%. Insect meal has a well-balanced essential amino acid profile. Hence it can be considered as a complete animal protein. Lauric and palmitic acids are in higher concentrations in the insect meal. Lauric acid is a saturated medium-chain fatty acid (MCFA) that has great antimicrobial activity.
Antimicrobial Peptides:
Insects contain some antimicrobial peptides that can act against bacteria, viruses, fungi and parasites providing natural resistance against them. This property can be explored to combat the antibiotic resistance of poultry birds.
Digestibility: The digestibility of various components of feeds such as dry matter, crude protein, crude fibre, ether extract, and ash is enhanced.
Growth Performance and Meat Quality: The growth performance is improved. Meat quality in broiler chicken is improved, which may be due to the balanced amino acid profile and the greater digestibility of crude protein.
Some frequently used insects as Meals
Common housefly (Musca domestica)
The housefly is present worldwide. Also, it can be reared on organic waste like kitchen waste and manure. Housefly meal (HFM) is an effective alternate protein source, especially for poultry farming, as it can provide energy and proteins. The HFM protein is balanced in all the essential amino acids. However, it contains a good percentage of lysine, threonine and methionine.
Black soldier fly (Hermetia illucens)
The black soldier larvae can grow on decomposing organic materials like fruits, vegetables, kitchen wastes, and manure. The environmental pollution caused by organic waste can be reduced by transforming the waste into useful biomass due to the growth of the larvae (Nguyen et al., 2015). The black soldier fly meal (BSFM) can be used as a complete replacement for traditional sources, such as soybean meal and fish meal.
Silkworm (Bombyx mori)
Silkworm pupae (chrysalis) are the sericulture by-products, which are generally discarded after cocoon spinning. Silkworm chrysalis meal or SWCM is acquired after the drying and grinding of the silkworm pupae.
Earthworm (Eisenia foetida)
Earthworms are an excellent source of energy, protein, and amino acids. The CP content in earthworms ranges between 50% and 70%. Earthworms can be used in the form of a meal, vermi- humus, or a mixture of the two.
Grasshoppers (Caelifera spp.), Cricket (Acheta domesticus), and Locust (Schistocerca gregaria)
Crickets, Grasshoppers and Locusts are also good sources of protein, essential amino acids, fatty acids, minerals, and vitamins for poultry.
Mealworm (Tenebrio molitor)
Mealworms are worm-like darkling beetle larvae. They preferably grow in warm, dark, and damp places. They can be grown on grains, leaves, spoiled food, and various organic matters. The larvae are rich in crude protein and ether extract.
Inclusion Level in the Feed
Inclusion level varies according to the species of insect and the birds. However, the range floats between 2- 20 % of the feed.
Advantages of Insect Meal
Better performance and feed conversion ratio are observed in poultry birds. Feed quality is enhanced. Insect meals can be a sustainable alternative to traditional protein sources like fishmeal and soybean meal. It increases the palatability of the poultry birds. In addition, the meat and eggs of the birds fed on insect meal are preferred to a high degree by the consumers. Apart from this, insects carry some antimicrobial peptides, which can act against microorganisms like bacteria, viruses, fungi and parasites. Insect meals can also improve the immune system and ultimately boost the health of poultry birds.
Challenges
The most important challenge is the cost-benefit analysis. Apart from this, some insects are known to be carriers of various diseases, which may be the treat for the poultry industry and humans (Makkar et al., 2014). For instance, housefly is the carrier of the fungus species, Entomophthora.
Conclusion
Insect meals can be a part of the poultry diet as an alternative protein source with no detrimental effect on animal performance and meat quality. The quality of insect meals must be maintained, as it depends on the rearing medium and processing methods. Also, the cost of production must be minimized. On the whole, insect meals can portray the role of sustainable feed sources for feeding birds.
References
Makkar, H.P.S., Tran, G., Heuzé, V. and Ankers, P. (2014). State-of-the-art on use of insects as animal feed. Animal Feed Science and Technology. 197:1-33. https://doi.org/10.1016/j.anifeedsci.2014.07. 008.
FAO. (2011). Food and Agriculture Organization of the United Nations. Small livestock, big impacts.
Chia, S.Y., Tanga, C.M., van Loon, J.J.A. and Dicke, M. (2019). Insects for sustainable animal feed: inclusive business models involving smallholder farmers, Current Opinion in Environmental Sustainability. 41: 23–30.
Bovera, F., Loponte, R., Marono, S., Piccolo, G., Parisi, G., Iaconisi, V. and Nizza, A. (2016). Use of Tenebrio molitor larvae meal as protein source in broiler diet: Effect on growth performance, nutrient digestibility, and carcass and meat traits. Journal of Animal Science. 94(2), 639-647. https://doi.org/10.2527/jas.2015-9201.
Cullere, M., Tasoniero, G., Giaccone, V., Acuti, G., Marangon, A. and Dalle Zotte, A. (2018). Black soldier fly as dietary protein source for broiler quails: meat proximate composition, fatty acid and amino acid profile, oxidative status and sensory traits. Animal. 12(3), 640-647. DOI: https://doi.org/10.1017/S1751731117001860.
