BSFL processing humanure for free chicken food

I was reading about different insect integrations with waste streams and came across this one:
http://onlinelibrary.wiley.com/doi/10.1111/tmi.12228/pdf

objectives To determine the capacity of black soldier fly larvae (BSFL) (Hermetia illucens) to convert fresh human faeces into larval biomass under different feeding regimes, and to determine how effective BSFL are as a means of human faecal waste management.

methods Black soldier fly larvae were fed fresh human faeces. The frequency of feeding, number of larvae and feeding ratio were altered to determine their effects on larval growth, prepupal weight, waste reduction, bioconversion and feed conversion rate (FCR).

results The larvae that were fed a single lump amount of faeces developed into significantly larger larvae and prepupae than those fed incrementally every 2 days; however, the development into pre- pupae took longer. The highest waste reduction was found in the group containing the most larvae, with no difference between feeding regimes. At an estimated 90% pupation rate, the highest bioconversion (16–22%) and lowest, most efficient FCR (2.0–3.3) occurred in groups that contained 10 and 100 larvae, when fed both the lump amount and incremental regime.

conclusion The prepupal weight, bioconversion and FCR results surpass those from previous studies into BSFL management of swine, chicken manure and municipal organic waste. This suggests that the use of BSFL could provide a solution to the health problems associated with poor sanitation and inadequate human waste management in developing countries.

So, feeding Black Soldier Fly Larvae fresh human faeces resulted in FCR of 2.0–3.3, which is better than a lot of insects, and better than BSFL on a lot of manures.

They could be sterilized (chemically, like fermentation, or with heat) and fed to animals. Chickens, in particular, would be a good one for this, maybe dogs, too.

An average human excretes 1.1 kg of faeces per day, which could make 330-500 grams (~1 lb) of BSF daily! That's enough for several chickens.

I did this very thing two consecutive summers in GA, and since then have done it also with dog and chicken manures. The BSF love it all. I'm astounded by the vile things they relish. Even deadly poisonous Amanita mushrooms from the forest.....converted into chicken feed! Moldy stuff of whatever sort (which will put chickens off of laying, quick, if fed directly). Road kill and slaughter trash. Of course you will want to locate the bin at a distance, since there may be some smell if you feed stuff like that; though this is less so with a vigorous colony. The residue left over I then put through my regular humanure protocol. But I have a suspicion, and intend this year to make trial of it, that the residue left from BSF can then go on to raise compost earthworms, thus multiplying the yields still further!

Alder Burns wrote:I did this very thing two consecutive summers in GA, and since then have done it also with dog and chicken manures. The BSF love it all. I'm astounded by the vile things they relish. Even deadly poisonous Amanita mushrooms from the forest.....converted into chicken feed! Moldy stuff of whatever sort (which will put chickens off of laying, quick, if fed directly). Road kill and slaughter trash. Of course you will want to locate the bin at a distance, since there may be some smell if you feed stuff like that; though this is less so with a vigorous colony. The residue left over I then put through my regular humanure protocol. But I have a suspicion, and intend this year to make trial of it, that the residue left from BSF can then go on to raise compost earthworms, thus multiplying the yields still further!

Yes, I've seen your posts about this, and it is very interesting. I've fed pig and poultry manure to them without issue.

Dr. Oliver did some research with BSF and earthworms, and they were a great match.

What I am curious about is any research into whether the BSFL have any effect on levels of pathogens in the before and after products.

From what I read, BSF void their guts as they molt and get ready to crawl out of the composting mass, and then on it goes into the guts of the poultry. Clean and cook your eggs and chicken meat and you should be safe. The poultry manure would be two stomach's remove from the humanure, so I'd guess the pathogen load would be much reduced, but just to be safe, composting this and/or using it on food crops that will be cooked is a safe bet. I sometimes put uncomposted humanure under raised beds devoted to potatoes.....after all, I don't eat raw potatoes!

Peter Ellis wrote:What I am curious about is any research into whether the BSFL have any effect on levels of pathogens in the before and after products.

There are numerous studies on that subject, here's one discussion: http://blacksoldierflyblog.com/2008/06/13/bsf-not-vectors-human-pathogens/

Abe, I am aware of that article. It references one study that addresses the impact of BSFL on e. coli and salmonella, which I admit I still have not tracked down and read through. Most of the work seems focused, as the paper linked in the op here, on how much they reduce the quantity of feed material and how efficiently they convert it into, well, Them

Considering that they are almost invariably being fed waste products (and I mean stuff with really minimal potential further use), I do not really see the point in studying the efficienct of feed conversion. That is a meaningful value when the feed has a cost associated with it. Not so much here.

I see the importance of how much they reduce the mass of their feed source. If they reduce a volume of waste material by ninety percent, that is a huge impact in terms of what you have left to dispose of. Considering that you can, in effect, run a figure eight pattern that runs pig poop into soldier flies into chickens into chicken poop into soldier flies into pigs and back to the beginning, it isn't an infinite motion machine, but it is a sort of regressive processing system that pulls every possible erg of energy... and yes, you would need to be feeding more into the system.

In tropical environments where biogas production is highly viable, there may be some real balancing to do to determine which option provides the best return in a given situation.

I continue to have some concern as to how effective BSFL are at reducing bacterial populations in manure. Not so much in terms of the larvae carrying pathogens to the chickens that eat them - and possibly on to us in eggs or meat- as in the remaining waste product when the BSFL are finished eating.

That remaining product needs to be dealt with in a healthy manner. I am hopeful that there is a straightforward method for reliably eliminating pathogens that does not require substantial energy inputs (heat sterilization would not be a first choice in my view). Would vermicomposting do it? I don't know, but would be very interested in information along this line.

What bacteria remain in the mass when the BSFL have reduced it completely? What mechanisms are effective in eliminating any remaining pathogens from this material?

It would be pretty amazing if you could dispose of humanure in a highly efficient, productive and sanitary manner that not only produced a valuable product but also kept housefly populations down and so reduced disease risks even more.

From what I have read and observed in my own system, houseflies and BSF are competitors for similar resources, and when both are present, the BSF dominate and, in a vigorous colony, prevent housefly larvae from establishing at all. Neither are houseflies attracted to the residue remaining when BSF finish with it. So directing dangerous manures and other farm wastes through BSF is actually an improvement over disposal methods open to housefly infestation. On our current small homestead, when I see housefly numbers on the rise, it's usually an indication that I need to go pick up dog poo! They don't get into the humanure buckets, which go either to the BSF first or directly into a screened compost pile.
Numerous resources are available on the safe processing of humanure on the homestead and larger scales. Temperature and time of composting are usually key, and to that I would add burial away from the surface splash zone and the choice of crops towards those that yield their edible product well off the ground, or are always eaten cooked, or a non-food product.
I have found through long experience (doing humanure on five different homesteads and farms since 1985) that the recycling of urine and humanure stops a very significant nutrient loss, and, over time, their use is a major contributor towards ratcheting up yield on the small homestead.

Peter Ellis wrote:Considering that they are almost invariably being fed waste products (and I mean stuff with really minimal potential further use), I do not really see the point in studying the efficienct of feed conversion. That is a meaningful value when the feed has a cost associated with it. Not so much here.

Well, this depends, because it is still a resource. If it is more efficient to feed it to earthworms or compost it, then you may choose another route. Earthworms have a FCR of 10:1 on herbivore manures, but not so much human waste. In comparison, BSF have a worse FCR (16) on herbivore manures. So, FCR is still important, because we want to maximize our resources. It depends on your situation, as well. Getting more chicken feed out of current resources is more important to me than needing compost.

Peter Ellis wrote:
I see the importance of how much they reduce the mass of their feed source. If they reduce a volume of waste material by ninety percent, that is a huge impact in terms of what you have left to dispose of. Considering that you can, in effect, run a figure eight pattern that runs pig poop into soldier flies into chickens into chicken poop into soldier flies into pigs and back to the beginning, it isn't an infinite motion machine, but it is a sort of regressive processing system that pulls every possible erg of energy... and yes, you would need to be feeding more into the system.

Yes, but at the same time, most people are buying all of the feed for the pigs/chickens, etc elsewhere, and if they integrate these through mechanisms like BSFL, they can drastically reduce the feed bill (protein is expensive). Consider the example in the OP, an extra 1 lb of chicken feed per day per adult Human in a house. Combined with some grain and vegs scraps, you could build a balanced diet for chickens around that. So, while the chickens might need some grain, they certainly wont need soy or fish meal, which is typically the most expensive part of rations.

Peter Ellis wrote:
In tropical environments where biogas production is highly viable, there may be some real balancing to do to determine which option provides the best return in a given situation.

Yeah, every situation is different and will require different approaches. This is just one more tool in the box.

Peter Ellis wrote:I continue to have some concern as to how effective BSFL are at reducing bacterial populations in manure. Not so much in terms of the larvae carrying pathogens to the chickens that eat them - and possibly on to us in eggs or meat- as in the remaining waste product when the BSFL are finished eating.

That remaining product needs to be dealt with in a healthy manner. I am hopeful that there is a straightforward method for reliably eliminating pathogens that does not require substantial energy inputs (heat sterilization would not be a first choice in my view). Would vermicomposting do it? I don't know, but would be very interested in information along this line.

Yes, I have that concern as well, and the waste from my BSF go to a hot compost bin. Hot composting would be good enough to kill most things, but such a reduction also means there is very little to deal with, so there might be other options, like ph/chemical sterilization.

Peter Ellis wrote:
It would be pretty amazing if you could dispose of humanure in a highly efficient, productive and sanitary manner that not only produced a valuable product but also kept housefly populations down and so reduced disease risks even more.

I completely agree, it is an exciting concept.

Now, there's another angle that isn't being discussed, and that is the potential of human consumption of the BSFL (after sufficient sterilization). You could theoretically provide the protein required for a human adult from his/her own feces, thus drastically reducing the food requirement and footprint. While most of us aren't prepared to eat shit-grubs, it still illustrates the potential resource we are ignoring. Imagine a world where humans don't require significant external protein...

Alder Burns wrote:From what I have read and observed in my own system, houseflies and BSF are competitors for similar resources, and when both are present, the BSF dominate and, in a vigorous colony, prevent housefly larvae from establishing at all. Neither are houseflies attracted to the residue remaining when BSF finish with it. So directing dangerous manures and other farm wastes through BSF is actually an improvement over disposal methods open to housefly infestation. On our current small homestead, when I see housefly numbers on the rise, it's usually an indication that I need to go pick up dog poo! They don't get into the humanure buckets, which go either to the BSF first or directly into a screened compost pile.

I've read in multiple sources that they actually release a "smell" that repels other flies. This may be part of the reason other flies aren't around the BSF bin.

Alder Burns wrote:
I have found through long experience (doing humanure on five different homesteads and farms since 1985) that the recycling of urine and humanure stops a very significant nutrient loss, and, over time, their use is a major contributor towards ratcheting up yield on the small homestead.

I've had the same experience, and when you look at these studies using those nutrients directly, it really reinforces what we already know - humanure has a lot of value!

ok, some data adjustments. Adult humans excrete .5 kg per day, not 1.1 kg per day, so product of BSF should be cut in half, too, so around 166g - 250g per day per adult human. Still enough to feed probably 5 chickens with grain to provide a balanced ration.

If the human could somehow figure out how to eat the protein from the BSF directly, 166g of BSF is enough to cover the daily protein requirements of that human.

Combine that with urine on crops, and you come real close to covering the nutrient requirements of the human from his/her own waste.

I have a question about stink.
I have accidently raised bsf in a bad composting situation.
The stink was incredible,unlike anything I have ever encountered, even as a plumber.
I am thinking that it might have been the build up of leachate, most sources say they stink less?

William Bronson wrote: I have a question about stink.
I have accidently raised bsf in a bad composting situation.
The stink was incredible,unlike anything I have ever encountered, even as a plumber.
I am thinking that it might have been the build up of leachate, most sources say they stink less?

Most bins drain the leachate into a closed container. The leachate does smell, but I don't find it offensive. The leachate is full of BSF smell, which means it will attract BSF adults to lay eggs and repel other flies.

My worst problems with smell have been early in the season when the BSF colony isn't very large, or if I put in way too much manure, etc. at once. In both cases the larvae simply can't eat it all fast enough, and so bacterial (and, if wet enough, anaerobic) decay sets in. But if you have a rocking large colony there might be a challenge in keeping it fed enough. A stable resource held in a dry state (dry coffee grounds, sun-dried dog turds, dry moldy food etc.) that can be soaked overnight and then fed off in daily meal sized batches is one way I've proceeded.....