Aquaculture for all

Feeding Fish Sustainably with Flies

Nutrition Health Sustainability +6 more

SOUTH AFRICA - With the worlds population ever on the increase, the demand placed on food sources, particularly protein, is already at record levels. Meat such as chicken and fish is in high demand, and this type of livestock need protein in their diet to grow, writes Georgina Starmer for TheFishSite.

This protein must be sourced from somewhere, and most of it comes from the seas. Poultry and fish that are intensively farmed are fed with a protein based fish meal, which is derived by many smaller aquatic creatures. The problem with this is that high quantities of these small aquatic creatures are needed in order to produce a small amount of animal feed, and this has serious implications for the long term sustainability of such a product.

Ken Stier writes in Time Magazine that in order to create 1 kg (2.2 lbs.) of high-protein fishmeal, which is fed to farmed fish, it takes 4.5 kg (10 lbs.) of smaller pelagic, or open-ocean, fish.

With around four times the amount by weight of protein going in as coming out, the efficiency of this way of making livestock feed is poor and unsustainable, particularly as agricultural feed for farmed livestock contains around 20% protein.

The overfishing of seas globally is not a new concept, and the fishing industry is now subject to a host of control measures that affect how much fish can be caught, and there are bans on fishing in some areas.

Around a third of the global marine catch goes into products that are not for human consumption, so solutions must be found before it has any more detrimental effects on marine life and ecosystems. For natural fish stocks to ever get even close to the levels they once were, more efficient ways of getting the protein we need must be developed.

Finding Solutions in Organic Waste

AgriProtein is a company in South Africa which has come up with a sustainable solution to the world’s demand for protein based animal feed.

Jason Drew, the founder and director of AgriProtein explains: “Nearly one third of the fish we take from our seas – some fifty million tonnes a year is used in our industrial agricultural and pet food industries.”

AgriProtein has worked out a solution that could have a radical effect on this problem, and has developed an animal feed that does not rely on the depleting fish stock to get the protein requirements. Instead, it makes use of something that the world has plenty of – organic waste.

It has turned the problem of the high amounts of waste that we produce into an abundant resource that can be recycled and utilised. The amount of waste going into landfill sites is a real problem that has a detrimental effect on the planet. It is now common to recycle paper, glass, plastics and metals, but it is recycling the organic waste, including sewerage, manure and blood from abattoirs that will help to make a real difference to the way we deal with waste, and the effect it has on the environment.

Mr Drew stated that “when we start to recycle these, we will be truly on the path to some sustainability for our planet.”

Using Flies

AqriProtein has created a fly farm that utilises the insects’ natural waste disposal qualities. They breed and grow fly larvae to process organic waste matter that would otherwise go to landfill or are costly to process.

In nature, flies lay eggs in waste such as animal carcasses or vegetation. The eggs then hatch into larvae that eat and dispose of the waste. This larvae is also the natural food of other animals such as fish and birds.

With AgriProtein, the process works just as it does in nature, but on a much larger scale. Organic waste is collected from restaurants, food factories, hotels and out of date supermarket produce. The company also collects carcasses and blood from abattoirs.

This organic waste is subject to strict quality control, is processed and blended into a formulated feed for the fly larvae. The larvae, or maggots, grow and are then turned into an animal protein feed called MagMeal™.

Mr Drew stated that “we've copied nature and led the process of making protein from waste nutrients profitably, sustainably and on a large scale.” The benefits of this are plentiful.

The waste gets reduced and processed naturally by the maggots, rather than it lying around in landfill sites, and the end result is a sustainable, healthy animal feed that does not rely on depleting the oceans of its wildlife. It is also quick to produce. Just one kilo of fly eggs can be turned into 380 kilos of larvae in 72 hours.


MagMeal™ consists of the ground up, dried larvae. It is a brown, crumbly textured feed that contains the nine essential amino acids that contribute to growth and health, meaning it is a complete animal protein.

Research shows that animals fed with MagMeal™ gain healthy amounts of weight.

One study conducted by Ogunji et al. (2008) was to evaluate the growth and nutrient utilisation of Nile tilapia, a commonly farmed species of fish in Africa. The fish were fed with MagMeal™ instead of a commercial fish feed. The results of the study showed that the fish gained good growth and health, and that it did not produce any stress on their systems.

The study also showed a better performance in the growth of the fingerlings when fed with MagMeal™, than when they were fed with other commercial fish food. This means that for Nile tilapia, and most likely for other species of farmed fish, MagMeal™ works as a replacement to commercial fish feed.

Not only that, it is also an affordable option when compared to the rising prices of importing other fish feeds, therefore benefiting fish farmers.

AgriProtein has raised over $11 billion to build two commercial fly farms, the largest one being developed in Cape Town.

Each farm will consist of over 8.5 billion flies that will be used to turn organic waste into MagMeal™, designed for poultry and fish, an extracted fat called MagOil™ designed for use in pig feed, and a soil conditioner, MagSoil™.

MagMeal™ is the ideal feed for chicken and fish as their natural diets consist of feeding on the insect larvae they find as they forage, and the product has received approval in South Africa.

At the moment, AgriProtein sell small quantities of MagMeal™ locally, but the first commercial amounts will be available for sale from the end of April 2015. Full production is planned to commence in August 2015 at which time AgriProtein will make 22 tonnes of larvae, which will yield 7 tonnes of MagMeal™ and 3.6 tonnes of MagOil™ per day. Although at this stage AgriProtein will not sell directly to the general public, sales will be provided to pre-approved buyers on a wholesale basis.

The expansion of the fly farm industry could eventually eliminate the need for trawling for fish meal, allowing the natural stocks in the seas to replenish. This would have beneficial effects on the food sources and habitats of many aquatic species.

It also relieves the pressure on agriculture, where producing protein based animal feed uses a large amount of land, water and agricultural fuel to grow crops. According to Mr Drew, this new industry is able to produce 600 tonnes of protein per hectare, compared with less than 50 tonnes of protein in an agricultural setting.

In the future, AgriProtein plans to develop around 40 fly farms worldwide, helping to solve one of the biggest environmental problems of the modern world, and also creating a solution to the need for protein.

Mr Drew explained: “The world urgently needs new and sustainable sources of protein. Fly larvae fed on existing waste nutrient sources is one of these.”

The simplicity of the concept is one that has been around for many years, but AgriProtein has researched and developed scalable ways to make it work. The farm breeds three different types of fly, the common house fly, the black soldier fly and the blow fly, and each species prefers different kinds of waste.

Getting the right farming conditions for the breeding and production of larvae took a lot of trial and error. Mr Drew explained that it took some time to find out the right temperatures, amount of light and humidity needed to breed the flies.

Now the right environment for breeding and growing larvae has been worked out, plans are in place in the future to scale up the industry.

This is an exciting time for business in the environmental sector, where the shift is made to developing a sustainable and clean future. AgriProtein is a recent winner of the WWF Climate Solvers Challenge and UN IFP Innovation Award for Africa. It is at the forefront of the developing nutrient recycling industry, and the potential benefits it has are not limited to feed production.

AgriProtein is carrying out extensive research programmes into other uses for fly larvae, such as in the healing of livestock ailments. At the moment though, the production of a sustainable protein based livestock feed is something could change the world, creating a better more sustainable ways to feed the growing population without further depleting the seas natural resources, and improving the ways that we dispose of our organic waste.

This article was taken from the October 2015 Sustainable Aquaculture Digital. To sign up for the February 2016 edition, please click here.

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