Black Soldier Fly Prepupae for Aquaculture Diets

In response to the questions of Jeff Glegg on 12/15/2013 1) how far will larvae migrate? a distance of 2 feet? 3feet? more? - They will go as far as they need to, we have found them up to 15m away from their original pod. --> how far should inclines be situated for the "self-harvest", from any area of the growth space? They can originate anywhere as long as it is on a sidewall of the pod. They will walk round and round untill they reach an incline. --> how do the larvae sense where the inclines are located? How do they know where to go? 2) If substrate (manure) is provided that is 6" to 8" thick, how many pounds of larvae can be sustained within a square foot or square meter area? 8" might be to deep. A rate of 10kg per square meter per day should suffice and you should harvest 10% of this in pre-pupae weight 3) Under normal temperature, humidity, feed conditions, if the BSF go thru 1 life cycle, how many larvae will 10,000 larvae become? What is the typical time duration for this? 4-6 weeks? - You will have a 45 day life cycle and a fly will lay 350 to 750 eggs - survivalbility will probably be your biggest issue. 4) Do the dead adult BSF have much nutritional value? - none whatsoever, you will pick up some crude protein which is in actual effect the nitrogen associated with the chitin. 5) Are there any major risks to losing the the larvae population? moisture, compaction, mould

A comment on conversion of substrate to black soldier fly biomass or what may be called feed conversion reminds us that some substrates have low yield in BSF biomass. For swine manure, 70% moisture, on a wet weight to wet prepupae basis, a "FCR" of 6.4 may be achieved. One experiment produced 26 kg of BSF prepupae per 169 kg wet swine manure. On a dry matter to dry matter basis, using 30% moisture for the prepupae and 70% moisture for the manure, a 2.7 "FCR" can be calculated. Another observation indicated that the same manure converted from 55 kg dry matter to 24 kg dry matter after soldier fly activity for 14 days, a dry matter reduction to 43.6% of original dry matter. The missing dry matter is not all converted to BSF. If it was, a 1.5 "FCR" might be calculated based on dry matter initially in the substrate to dry matter assumed to be in BSF. Manures with more lignin will have poor conversion to BSF biomass. So, using conversions that assume about 25% recovery of substrate dry matter as BSF dry matter only works with the higher quality substrates.

Hi, This is a very interesting thread (and topic!) - I'm looking into bsf as some component of fish feed for aquaponics systems in developing markets (current strong interest in Cambodia and Thailand). After reading a ton of information, I am quite optimistic about the general potential, one thing I am very surprised about though is the apparently very high level of funding by companies in this sector (as I'm assuming they expect to require at least something very roughly in that range even if they might be playing it safe) - AgriProtein in South Africa, PROteINSECT and a few others all seem to be operating on multi-million dollar/euro budgets. It appears form reading all the papers that the general process is reasonably well understood but production processes and operations have to be optimized. I would be interested though in what exactly is proving to be so capital intensive there and if it is absolutely paramount or if a conscious low-tech way forward in a market with very low labor costs and relative high temperature/humidity (hopefully significantly reducing the need for environmental tweaking) could work albeit at probably significantly lower productivity levels as the aforementioned players might reach - especially the images from Indonesia earlier on hereby are very interesting). I'm very grateful for any comments! Thanks! Jonas The most shocking statement in this regard come from the Dutch assessment of insects in animal feed which quoted a first big factory for AgriProtein Technologies would cost $10m - it didn't say for what scale but it must be absolutely massive at that size...

Black soldier fly are very good at bioconversion. However, efficiency depends on substrate type and culture conditions. Also, substrate cost is a big factor in scale up of the culture of any insect. Low cost substrates may carry undesirable market perceptions or legal requirements. And, other insects are being compared to the black solder fly, some with confinement requirements in order to prevent access to human diseases and thereby short circuit their vector characteristics. As mass culture develops, Competing systems will chose the right combination of species, system and substrate.

Dear Professor Burtle, Thank you very much for your response. Would you therefore say it is reasonable to assume that a significant portion of the funding for these players is actually still focused on research outside of "core" bsf farming operations? I'm especially curious/concerned about whether it is safe (obviously within typical limits of running into unexpected operational issues) that a fully functioning farm could be setup for significantly less money given sufficient access to cheap food waste (source: spoilage from supermarkets/restaurants/hotels)? (it kind of seems like a huge jump from home system or even supposedly properly engineered like a biopod to a $10m factory with the sweet spot for me lying somewhere in between...) - obviously, investing into technological improvements is always a good idea but especially in my context upfront capital expenditure most likely will be an issue, hence, the parameter to optimize for first is break-even and only secondly highest possible yield... Thanks! Jonas

As you have seen the Indonesian experience, that might be within the scope of your intended investment. Colonization and harvesting are two points of control that I suggest you focus on. Labor economics vary from country to country and may also be part of the considerations when scale is chosen. Aside from black solder fly culture considerations, substrate handling and product flow must be considered. On large scale operations, the cost of infrastructure is considerable (see grain or waste handling industries). Contracts for the substrate must be obtained and maintained. Some have started in the black, but ended operations as the substrate price increased, due to competition from other buyers or energy related costs. I advise a partnership with an economic analyst who is familiar with the feed manufacturing industry when considering scale up.

When a substrate is considered trash, begins to have value, the problems begin. An alternative is to link produccon of soldier fly larvae to integrated production systems, feces, mortality, production residuals become substrate.

Correct. An example is wet brewers grains, once valued at $40 per ton, then went to $120+ per ton. Since this product is not ideal as a soldier fly diet, that increase in price caused us to look at other substrates. Also of note is that solder flies like a certain amount of starch or sugar in their substrate. Hence, some begin with a substrate base with corn meal, then build from that point.

A substrate that has given me very good results are fermented pig manure, the attraction to adult females lay eggs is very good. Pig manure is to mix, bring it to 60% humidity, 5% mixed with molasses leave covered but not sealed.

If pigs are raised on concrete the manure can be obtained at about 60 to 70% moisture. For the carbohydrate source, have you tried yams or potatoes or plantains?

Ok Taro babanas, cassava and sugarcane juice too.

Dear Oscar ( and Prof Burtle), Thank you for this ongoing and very interesting information sharing... One reason why I am straying away from the manure-based solutions despite quite well researched (obviously your 2005 report comes straight to mind Prof Burtle) is the potential regulatory issues. I am looking at feed sources for aquaponics systems (i.e. fish feed) where in order to make the commercials work, it is paramount to be able to have an explicit organic certification or at least be "as-good-as" to realize price premiums in produce (in some countries currently water-based growing can not be certified organic as there obviously is no "organic certified" soil involved). This is currently especially true in developed markets but I expect it to over time also be the case in developing markets. With legislation to my knowledge often prohibiting the use of animal manure in human food, I obviously would prefer other sources if possible. @Oscar - what are you using your produce for if I may ask?

I use this substrate for the first crop of pupae and establish my colony in nets, and obtained the eggs, you can use an organic substrate such as fruit crops crop oragnicos waste, organic waste from households etc.

Yes, manure is a regulatory and perception challenge. Different rules apply to different countries. Currently, I am working with grain byproducts combined with an attractor. The byproducts are almost always high in fiber and not the best substrates. Even manures vary in suitability due to their composition. Ruminant manure may be less suitable than swine or poultry manure, but poultry manure that contains a lot of bedding material may not be as good as manure collected from caged laying chickens. Many items have been utilized but from mass culture of black solder fly, a local source of a starchy substrate is important. Also micronutrient requirements of black solder fly are little reported. Adding supplements of yeast as a source of B vitamins seems to help grain substrates, for example. Black soldier fly are high in minerals, notably calcium, so a substrate needs calcium as well as other essential minerals. Manures have all of these things as remainders of the undigested portion of animal diets. When black solder fly is used to bioconvert other substrates, keep in mind the needs of the larvae.

Thanks so much for an informative article. I am currently in Singapore but we do not have an agricultural sector but we do have a thriving soy industry that produces up to 30 tons of okara waste per day. Initial studies have shown that black solider fly insects and pupae are able to grow diet, and we are planning to begin live feed trials on Tilapia with these insects to ascertain if Okara will not indirectly affect the fish.

Okara is another fiber rich byproduct that might need add-back of a sugar in order to make a better substrate for black soldier fly growth. If BSF larvae are inoculated onto the okara, bioconversion would occur. However, without added sugar, would okara attract BSF adults? Sources of sugar include mellon waste, sweet potato waste, banana waste, molasses processing waste.

Do you have some experience using rabbit manure as substrate for BSF I'am planning to run some trials this year.

The moisture content of the rabbit manure would need to be 60 to 70%. Attraction of the BSF to the manure is a question that I have. Have you seen any adults around your rearing area in the past? If you want to attract the BSF, you may need to add a material that has a sugar content.

I have not seen any adults of BSF around but they should be somehow around the place since last year there were plenty of larvae under the cages I plan to add something sweet to the feces to atract them this year

Is someone leading the charge with the FDA to allow larva raised in animal manure to be used in aquaculture? Do you see that being allowed in the near future? Is is currently illegal or a grey area? Where can I buy bulk BSF eggs or seed larva? Thanks, James Zitting 417-276-1622