Fighting antimicrobial resistance with insect-based livestock feed

The Hindu

6 days ago

Traditional livestock production systems have severe environmental consequences, including high greenhouse gas emissions, extensive land and water use, and risk of fostering antimicrobial resistance (AMR). Together with the steadily rising demand for nutrition, global and regional food systems have been exploring alternative ways to sustainably maintain their supply chains. Insect-based feed has emerged as one promising candidate.
The Indian Council of Agriculture (ICAR) and its affiliated centres have already been strengthening the adoption of insect-based feeds in the country. In March 2023, the ICAR-Central Institute of Brackishwater Aquaculture (CIBA) signed an MoU with Ultra Nutri India, Pvt. Ltd. to explore the possibility of using insect-based feed in aquaculture. The aim was to use black soldier fly (Hermetia illucens) larvae as an ingredient in aqua-feed to improve growth and immunity.
In June 2024, CIBA and Loopworm, a Bengaluru-based manufacturer of insect-based proteins and fats, inked another MoU to evaluate the use of insect-based feed products in shrimp and Asian seabass. In January 2025, the ICAR-Central Marine Fisheries Research Institute confirmed a formal MoU with Coimbatore-based Bhairav Renderers.
AMR and livestock production
Animal husbandry accounts for more than half of all antibiotic use around the world and is expected to increase to 200,000 tonnes by 2030, up 53% from 2013. Over the last 70 years, antimicrobial compounds have been becoming embedded in livestock feed. They are used to treat diseases as well as to boost growth, in turn raising productivity.
The excessive or inappropriate use of antibiotics in this regard can lead to AMR, which endangers public health. Traces of antibiotics left behind in the intestinal environments of livestock impose selective pressure for bacteria in the gut to acquire and maintain antibiotic resistance genes. These genes replicate when they are expelled into the surrounding environment, such as soil or water, increasing the possibility of human exposure, especially for those who work in agriculture.
It has been projected that the number of deaths worldwide from antibiotic-resistant infections will increase from 700,000 a year in 2014 to 10 million by 2050.
The increasing demand for proteins of animal origin has in turn increased the costs of production and has encouraged farming practices to intensify. Ultimately, farmers are forced to use non-essential antibiotics to boost growth. The use of such antibiotics remains mostly unregulated in many countries, especially in LMICs.
The type and frequency of antibiotic-based animal feed consumption differs across continents and depends highly on socioeconomic conditions, regional demand and production, farming systems, and the national legislative framework. Some common antibiotics in use as feedstock in LMICs are chloramphenicol, tylosin, and TCN (a powdered mixture of oxytetracycline, chloramphenicol, and neomycin); developed countries have banned their use. In humans, over-exposure to these drugs can eventually increase the risk of kidney disease, cancers, and aplastic anaemia.
These realities prompted researchers to explore the use of insect-based feed to keep AMR at bay. As of today, 40 countries have accepted and issued regulations to use insect-based feed for animals. Examples of such insects include black soldier flies, house flies (Musca domestica), compost worm (Perionyx excavatus), grasshoppers (Locusts), small mealworms (Alphitobius), house crickets (Acheta localus), tropical crickets (Gryllodes sigillatus), and Jamaican field crickets (Gryllus assimilis).
Pros of insect-based livestock feed
Insects are nutritious and are healthy additions to human and animal diet. They are good sources of fats, proteins, fibres, and micronutrients like zinc, calcium, and iron. In their natural habitat, both aquatic and terrestrial animals eat insects. Rearing insects emits less greenhouse gases than rearing other sources of animal protein. In most cases, insects are raised on organic waste because they can quickly transform low-grade waste into high-grade crude proteins, fats, and energy. For example, to generate the same quantity of proteins, crickets consume 12-times less feed than cattle. Rearing insects also requires fewer resources, especially land and water, compared to other livestock production enterprises.
Insect-based livestock feed is also an attractive option because of its lower overall cost and the ease with which producing it can be made a sustainable activity. In other words, such feed has a better benefit-to-cost ratio in terms of production cost.
In fact, some studies have shown that the use of insect-based feed can be even more cost-effective because it provides better digestible proteins than fishmeal- or soybean-based feeds. For example, per one estimate, one kilogram of fish meal can be replaced with 0.76 g of crickets (75% crude proteins), 0.81 g of termites or silkworms (70%), 0.85 g of black soldier flies (66%), 0.91 g of locusts or yellow mealworms (60%), and 950 g of mopane worms (56%). Similarly, one kilogram of soybean meal (49% crude proteins) can be replaced with 0.74 g, 0.79 g, 0.83 g, 0.89 g, and 930 g of the same insect species, respectively.
The U.N. Food and Agriculture Organisation has estimated that food production will have to be increased by 70% by 2050 (with meat production expected to double) to meet the world's demand. Unregulated and excessive use of non-essential antibiotics increases the risk of environmental antibiotic-resistant genes in livestock farms. Research has outlined the potential for insect-based feed to become a climate-smart alternative to conventional feed because of its ability to shrink the environmental footprint of livestock farming.
At the macroscopic level, the ICAR is still streamlining research and collaboration on insect-based feeds; all the same, efforts should be made at the system's periphery to raise awareness. Given its advantages for the environment, biology, and economy, insect-based feed stands to be a crucial component of livestock production.
Irfan Shakeer is an epidemiologist at Clarivate India. Iswarya Lakshmi is senior research associate, Ashoka Trust for Research in Ecology and the Environment (ATREE), Bengaluru.