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Ultra Cheap Mealworm Production



  • Again edepro53, - Yes, egg shell calcium (as calcium carbonate) is good calcium to mix in with feed for egg laying ("layer") chickens; bear in mind we are now specifically discussing a chicken raised for a particular life cycle. Details can be found in the free full text of the following study: (2011) "Effects of eggshell calcium on productive performance, plasma calcium, bone mineralization, and gonadal characteristics in laying hens"; free full text =

    Notice that they used very small amounts of ground egg shells over the size of 6 mm & over half (59%) of the powder was under 2 mm in size. You would do well to get some mesh that will let the 1 mm diameter powder fall through; that small stuff would not be worthwhile mixing in with layer hen feed &, although taken in is not going to be of any use for them inside to make into a new egg shell.

    Quote: "... {40%} ... eggshells ... 2 to 5 mm ... sufficient retention times for Ca in the digestive tract ... large-particle ... retained in ... gizzard ... longer ... enhanced ... eggshell formation during the nighttime ... particle size ... {minimum} 1.00 mm in diameter ...."

    This study's method gave a ground product with only 35% calcium; you can see under author's sub-heading of "experimental diets" they leave both membranes on. Their preparation method is stated there & is easier than ones where need to remove inner membranes, but their end-product has lower concentration of pure elemental calcium atoms than if got rid of those membranes.

  • edepro53, - Back to my old comment about phyt-ase enzyme you asked me about & how to reconcile that with using mealworm larvae to feed chickens. Let's take this in the context of data I recently mentioned.

    If you add 20 gram calcium /Kg to mealworm larval feed of wheat bran then those late instar larvae will contain 75mg/100 gr (0.75 gr./Kg.) of calcium+ a bit more than 300 mg/100 gr (3 gr./Kg) of phosphorus. If you add calcium at 40 gr /Kg, 60gr/Kg or 80gr/Kg then get (in that order, respectively) larvae with calcium having 150mg/100 gr., 200mg/100g or 225mg/100 mg + a bit more than 300 mg phosphorus/100 gr larvae.

    Phyt-ase enzyme supplements are added to high grade commercial "broiler" (cooking) chicken feed because it's basis is a blend of soy meal (de-fatted) & corn meal which have low phosphorus; plus they add supplemental ingredients. You grow pigeon peas (in the past Hawaii blended it them 50:50 with cracked corn for feeding poultry plus supplementals) & dry pigeon peas (assuming an average variety) have ~ 71.3 mg of calcium/100 gr. + ~ 142.4 mg of phosphorus/100 gr.; & in comparison soy meal has 24 mg of calcium/100 gr + 67 mg of phosphorus/100 gr. & corn meal has 31 mg of phosphorus/100 gr.

    The difficult thing about making linear predictions is that when look at 3 week 'broiler" chickens fed a typical broiler feed phosphorus in soy meal (de-fatted) the there is 0.7% of total phosphorus in the feed (from the soy) but on 61% of that amount is actually bio-available; although have no data, I'd assume that the phosphorus in pigeon pea meal will be likewise only 61% of the total pigeon pea meal phosphorus is bio-available for a 3 week old broiler. In contrast, for that 0.3% of corn meal in the broiler feed only 29% of that amount is bio-available. Again, lacking specific data let's assume pigeon pea meal phosphorus has the same availability as soy meal (61% of total phosphorus) for broilers.

    This phosphorus bio-availabilty comes from (1996) "Efficacy of supplemental microbial phytase at different dietary calcium levels on growth performance and mineral utilization of broiler chickens"; abstract upper right has free full link to Oxford Journals publication = Then they determined that if you added in 600 units/ of phyt-ase enzyme to a diet that had 0.6% calcium it compensated for the relatively low phosphorus in soy+corn broiler feed; plus it kept levels of zinc, copper & magnesium optimal (verses feeding broilers with 1.0% calcium + the same units of phyt-ase enzymes.

    Table 2 shows that 3 week old broilers weigh 616 grams & needed to eat 811 grams of soy/corn feed supplemented with 0.6% calcium +600 units phyt-ase; while weighed 636 grams but needed to eat 830 grams of soy/corn feed supplemented with 1 % calcium + phyt-ase. And without the phyt-ase supplementation with 0.6% calcium the 3 week old broilers weighed only 591 grams (needing 780 gr of soy/corn feed); while without the phyt-ase with 1.0% calcium the 3 week old broilers weighed just 555 gram (needing 783 gr of soy/corn feed).

    If you can grow pigeon peas & field corn (maiz), then mix in a partial amount of calcium enriched mealworm larvae plus any supplemental nutrients this might be made even better by adding in phyt-ase. One unit of phyt-ase in not a gram measure but rather is the amount you need to free up 1 micro mol of inorganic phosphorus/min. (at 37*C, 5.5 pH of 15 Moles sodium phytate.

    Different producers vary, for example one gram of phytase from Canadian wholesaler Ubilcorp has 5,000 units of phytase/ gram. An expensive source Sigma Aldrich sells 5 grams of phyt-ase for US$195; this would be too expensive for home use, but you might find a cheaper source (ex: ask China producer if can buy their minimum sample size).

  • Again edepro53, - There is 0.123 unit of phyt-ase enzyme/gram (dry weight) of the "yellow/golden" oyster mushroom Pleurotrus cornucopiae ( variety Citripileatus). But some report much higher phyt-ase units/ gram & this is often in terms of fresh wet weight; the variety's stock & time of growth probably account for the difference in phyt-ase units.

    Oysters are of the easiest mushrooms to grow for novices & suitable for your warm climate (there is a Pleurotus cornucopiae variety florida); you incubate the spores (see for ~2 weeks, pack them in plastic bags & harvest in ~ 4 weeks. (Kits are also available, see; &

    The mushroom easiest to use mixed with bran (rice or barley) & ferment this for 2 months; then that is the carrier to blend in with feed. Note: I have not fed this ferment ingredient to poultry so you should consider it experimental before giving to more than one actively growing chicken; & then, if seems safe, to one that is very young.

  • edit: - I looked in my notes & found that for "yellow/gold" oyster mushroom a recent analysis was there are 0.188 - 0.238 units of phyt-ase enzyme/gram of fresh (not dried) mushroom; so suggest this is the best data to rely on for reference. If you sterilize feed just don't heat the oyster mushrooms to 60Celsius or will totally degrade phyt-ase (within 10 min.) & expect to lose 25% of the phyt-ase units if heat the mushrooms to 50C (for 10 min.); using home-grown ones the are visibly healthy & sensibly handled wouldn't need high heat processing.

    Apparently you do not actually need to ferment common edible mushrooms; which will make it much easier to mix dried oyster mushroom into small batches of feed to achieve a reproducible phyt-ase supplementation. So, if are finding websites saying don't feed chickens mushrooms take a look at how much dried mushrooms (Portabella) this sample study published in (2010) journal Poultry Science, Vol. 89(2); the researchers started feeding broiler chickens it when 1 day old. "Performance and antioxidant status of broiler chickens supplemented with dried mushrooms (Agaricus bisporus) in their diet"; free full text

  • Thank gringojay, as always you are really neat and based on yours answers. Wonderful !. I'm studying your answers and documents links also. I will try to point out practical applications for breeding mealworms as hens itself. I could know what your profession / occupation? I am impressed and happy with the quality of their responses. Regards.

  • Excuses, I mean: I am impressed and happy with the quality of your responses. Regards.

  • Hello, gringojay, I read your answers and the documents you referred me. I will try to summarize in order to outline practical applications focused on designing an ideal substrate for mealworms: nourishing / inexpensive. Mealworms 1. It is clear that we must provide calcium (60 to 80 g of calcium carbonate per kg of feed) on mealworms substrate if we are to truly nutritious for use larvae as feedstock. 2. Similarly, it should provide nutritional supplements that increase the content of phosphorus, which is typically low in mealworms (about +/- 3 g / Kg.) 3. It would be interesting to establish what the most appropriate and economical sources of both calcium carbonate and phosphorus as minerals additives in the mealworm substrate? I was reading a work in Spanish ( ) which states that a wheat bran substrate with apples (25g / 35g of substrate) as a source of moisture significantly increases the levels of phosphorus in larvae. While a substrate of rice flour and potatoes (25g / 35g of substrate) showed the highest values for calcium content. I wonder if that proportion of moisture source (apple / potato) is quite high and could encourage mold contamination? Regardless of the need to place certain sources of moisture in the substrate, I keep thinking of locating more easily quantifiable dry additives. As a test I have fed mealworm with slices of sweet potato, preferably orange pulp is richer in beta carotene, and had excellent acceptance by the larvae. I have noticed some resistance to mold attack. Different studies on its chemical composition agree on the content of phosphorus and calcium. Translated from Spanish quote an example: "___Your nutritional value per 100 g of tuber greater proportion comprises water74% , fiber 1.2%, fat 0.2%, protein 1.2% , fat 0.6 g , carbohydrates 21.5 g, sugar 9.7 g , starches11.8 g , sodium 41 mg, potassium 385 mg , phosphorus 55 mg , calcium 22 mg , iron 1 mg; magnesium also copper, zinc and chlorine. In addition, the sweet potato contains vitamin C 25 mg; Vitamin A 667 IU; vitamin B1 0.1 mg; vitamin B2 0.06 mg ; vitamin B3 52 mg . _" Sweet potato leaves provide almost the same analysis, they are therefore considered to be used as fodder. Worth considering whether it would be used as cheap source of moisture and nutrients 4. In a previous post you recommend a solution of vinegar eggshells to provide calcium to the substrate. I wonder if his application represents a high risk of mold contamination. Especially if the applied amount is exceeded, which seems likely to happen frequently. The other risk lies in applying very little for fear of excessively wet. I think the ideal would dry additives to be more practical and safe. . Poultry 5. .- To improve the assimilation of nutrients in poultry feed should have a proper balance of calcium and phosphorus (about 21 grams of calcium / kg and 8.4 g / kg phosphorus, for example) 6. Phytase enzyme plays an important role in the assimilation of nutrients and poultry lack this enzyme. So chickens should receive supplemental phytase with feed. 7. Fresh yellow / gold "oyster mushroom are a very good alternative as a supplement in feed for chickens because it provides phytasa enzyme. On the internet it is very easy to acquire spores or mycelium to easy grow these mushrooms. 8. As for pigeon pea, I'm using the fresh and cooked pigeon pea foliage only because raw seeds have certain levels of toxicity and the presence of anti-nutritional factors. Moreover, if boiled, pigeon pea seeds were not very palatable for hens. Maybe if I produce enough pigeon pea crop , I could bake it and grind it to combine with other grains and cereals. But to have a continuous and secure supply, it requires large tracts of land devoted to cultivation, with consequent farming. Cajanus foliage, with good protein, is abundant throughout the year, with few requirements and excellent regrowth as response to systematic cuts. I think this could outline the issues we have addressed in recent days. I hope I have not forgotten something important. Thanks in advance for your comments. Regards

  • Hi edepro53, - I'm not really sure what specific input you want me to address. Mealworm larvae are technically omni-vores & can consume a number of different items. It seems counter-productive to rear them on a diet that has expensive ingredients; they do need a significant amount of carbohydrates in their diet & cellulose is not the same thing.

    I tried feeding a few generations on bran plus shredded mixed vegetables in the form of humid (but not seeping wet) pulp from a local juice bar; so I your foliage items might be considered similar . At young age the larvae did not make an appreciable dent in vegetable pulp; it basically dried up in the grow bag & did not foster mold,

    The de-hydrated pulp was very clinging (especially the green flecks of matter) to larvae at harvest time & made cleaning the larvae significantly more labor intensive. I tried just putting a pinch of pulp atop the bran on one side once the larvae got bigger & still found it drying out with no sign of significant consumption of the green matter. I'd say that pulp was mostly carrot with some beet, celery, parsley, kale, ginger - maybe the larvae were repelled by some component & your greens will be better received.

    Now, once I switched to pure carrot juice pulp the larger larvae at a certain point went for it in a big way; carrot pulp has cellulose but also a good deal of residual "sugar" (carbohydrate) . Elsewhere in the Forum I detailed this & there are some pictures Andrew posted for me of the evidence of orange frass atop older buff colored frass; see if the search function can locate details on why I think late instars are fond of carrots.

    My conclusion was that until the larval mouth parts are big enough they more readily solubilize nutrients from bran than chew on vegetable matter. At this point I don't bother giving the larvae carrots until they are a few instars along ( I grow separate generations in their own grow bag & so most groups will be within about a week of each other in time from hatching); young larvae reared on carbohydrates (ex: bran) do not need to "drink" water from a vegetable placed inside their bin because water is formed as a consequence of carbohydrate utilization (mealies inside sacks of stored grain are not forced to go find water).

    Thus you may find the plant items you would like to feed to your larvae are going to be wasted on young larvae & yet once they are older the same plant will be well received by them. As for anti-nutrients: in a sense these are everywhere in plants & if they are not toxic then usually small amounts of anti-nutrients can be ingested without bad results. An old agricultural report from Hawaii observed than chickens would deliberately flap up to snag pigeon peas from the plants & with this in mind I doubt that pigeon peas will be toxic to mealworm larvae if you tested them out on a few late instar larvae.

    Anything else I'm overlooking?

  • Again edepro53, - Old Nigerian data on 2 raw pigeon pea varieties (brown & cream colored - obviously your local strains can show different specific analysis) shows they have no detectable alkaloids nor common saponins. Tannins are 2 times greater in the brown vs. cream variety (0.14 vs 0.1 mg/100 mg bean respectively); for tannin to be a horrible anti-nutrient in food for mammals (insect probably varies from this) then tannin has to reach 10% by dry weight. Both pigeon pea varieties have a lectin content of ~0.09 mg/100 mg; & we can eat white lima beans which have lectin content of ~ 2.8 mg/100 mg.

    Raffin-ose in pulses are what gives us intestinal gas & there is ~ 0.4 mg/100mg in the brown pigeon pea vs. ~ 0.6 mg/100 mg in cream colored ones. For verbac-ose, which is also found in faba beans & other true peas , in brown pigeon peas there is ~1 mg/100 mg & cream pigeon pea variety ~1.6 mg/100 mg. We readily can eat lentils, chickpeas & lima beans which have stacchy-ose; there is ~0.9 mg/100mg stacchy-ose in brown pigeon peas vs. ~0.3 mg/100mg in cream varieties. And finally there is ~1.2 mg/100mg sucr-ose in brown ones vs ~ 1.7 mg/100 mg sucr-ose in cream colored pigeon peas.

  • @andrew , Hello, I've been watching the tower baskets on the Web of Vela Creations and I note that the six growing nylon bottom trays are superimposed. This assumes that the frass from first tray falls into the next and so on until it is finally collected in the last tray containing not mealworms. I would like to know your opinion on whether this system frass transit through several baskets is effective and if it involves some kind of problem for larvae health. I tried several times to communicate with Vela Cretions through his blog and emails, but have not received a response. For that reason I am consulting you. Greetings and thanks for your answers.

  • @gringojay, Hello, I regret that in my post on August 27 generated some confusion. Originally, I divided the text into two parts. Unfortunately, the format of the forum took it as a single block. Part 1 referred to Mealworms (items 1 to 4) and Part 2 refers to poultry (items 5 to 8). So everything about pigeon pea is referred to feed chickens. In many tropical countries of Africa and America, cajanus is consumed as dried or fresh beans, similar to the consumption of peas. Always cooked as raw have some toxicity to both humans and livestock. However, for the chickens I am using only the protein-rich foliage.

    Moreover, I still have much interest in specifying what the calcium additive recommended for the mealworm substrate, keeping in mind feeding layers. Regards..

  • Hi edepro53, - Mealworm frass actually has 3.5 time more calcium per than the larvae do (one analysis showed 1538 mg calcium/kg frass vs 435 mg calcium/kg larvae; data indicates that normally (un-supplemented) for every 1 part calcium mealworm larva have 16.9 parts phosphorus ( & there is only 2 times as many mg phosphorus/kg frass than mg phosphorus/kg larvae). Which indicates they are not pre-disposed to hold on to ingested calcium; as the following seems to explain.

    (1997)"Feeding captive insectivorous animals: nutritional aspects of insects as food" concluded that because (edited quote) " ... extended consumption of high calcium diets (particularly by crickets and mealworm larvae) may lead to high insect mortality ... rotating insects onto the high calcium diet and feeding them out on a regular basis is critical ...." Other researchers noted that when dose with high calcium the elevated internal calcium level goes up at a liner rate by 24 hours & then goes down in a week - especially if supplement with elevated amounts of calcium.

    I calculated earlier that a safe steady calcium supplement guideline is (by volume) 0.25 cup powdered calcium carbonate for 4.5 cups of grain/bran given regularly to the mealworm larvae. If you are trying to formulate how much calcium you are making available there are 500 mg of calcium in 1,250 mg (1.25 grams) of calcium carbonate.

  • Do you think mealworms can eat urea? It sounds like they have gut microbes which can digest many things, polystyrene included, so I am wondering if a non-protien nitrogen source such as urea, which is used in some things like cattlefeed, would work for mealworms? When it is used in other feeds, it is converted to protien nitrogen by microbes in the gut of the cow, etc. -- at least that is my understanding of it all. If mealworms can be fed urea, which is exceptionally cheap and very high in nitrogen, it might yield a much cheaper over all substrate, as it would be supplementing a cheaper carbohydrate source than wheat bran.

  • @grigojay Hello, I wanted to let you know that I have placed whole carrots in the box with larvae 2 and 3 weeks old, and I noticed that they eat quite relish. In 4 or 5 days they have consumed carrots almost completely.

  • Hi edepro53, - larvae go through instars faster at higher temperatures. One set of data gives a 25 day period for completing all larval transitions (instars) to pupation at 31Celsius (88F); with good survival rate of 70-75%.

    I no longer fuss much with my larval colony; I only environmentally control temperature/humidity for my beetles, eggs laid & hatchlings. When they won't fall through mesh grow bags they are moved to a different interior room where built a tall rack for them.

    Daily swings of temperature are not so extreme indoors; however, humidity is definitely on the low side. Each week of beetle eggs' hatchlings go into a separate grow bag & under my lax conditions any mesh grow bag living generation gets interested in carrots in their own time.

    The different age groups are suspended in a serial stack of grow bags & since I cull them from every 7 - 10 days from the breeding facility I know each hanging bags relative ages. I don't bother anymore putting carrots in a grow bag until have installed in the stack 2 younger generations in their respective grow bags.

    My tactic is not ideal for a commercial operation; their life cycles are slower than optimal. The mealies survival rate is also less than it could be - but with a series of grow bags there is a regularly staggered output .

  • Hi, @gringojay, if I understood correctly, there are reports of larvae complete their full development from birth until they pupate in 25 days at 31 Celsius? That's amazing! I keep my larvae in an indoor environment with an average temperature of 25 Celsius and I thought they were growing well, but are still far from reaching a level sufficient to serve as food for chickens size. I'm counting the larvae reach maturity in about three months. I extract the eggs every ten days and put in a new box with new substrate to keep boxes with larvae of the same age level.

    Since next November I'll spend enough time in a tropical environment and will have a larvae at an average indoor temperature of 30 Celsius. I'll see how fast they grow.

    I am using self-cleaning trays in a tower arrangement, but I have doubts about whether there will be negative effects with frass passing through from one tray to another. What do you think about it? Regards.

  • Sorry Edepro53, - I have to definitively rule out that time line because the data is from a pest control company that only described it's beetle as the "Darkling Beetle". Many times Darkling Beetle is used to describe "Yellow" Tenebrio molitor mealworms & after looking at more leads from the company's website I concluded they were actually referring to the "Lesser" Alphitobius diaperinus mealworm.

    The product entomologist, Dr. Jim Arends, has association with a Department of Entomology (N. Carolina State U.). I found a publication of his that uses the phrase "Darkling Beetle" & in parenthesis specifies A. diaperinus.

  • @edepro53 - in a small growing situation I do not suspect that co-mingling frass would cause a major problem. In general as a best practice I think it is best to isolate waste from parallel cohorts as it can be a vector for disease within the colony. It would be trivial to add an inter-layer frass collection in VelaCreations' tower - for instance a cheap baking sheet from a dollar store would probably suffice

  • Hello, @andrew, @gringojay and any member can answer, I'm trying to point out some aspects of reproductive behavior of Tenebrio and I thank you what you can contribute.

    1- Oviposition takes place at night or during the day? There is a time when it is most intense?

    2- I read that the females are very productive for 3 or 4 weeks and then egg production decreases significantly. What is the reality? Until what age should be kept breeding adults?

    3- I read that also put adult beetles on wet blotting paper overnight, it stimulates the production of eggs. You know something?

    Greetings and thanks.

  • Hi edepro53, - 2nd question focus on only a linear relationship about eggs might be missing some relevant issues.

    For T.molitor it is actually the progeny of older beetles that grow faster than those born from young parents. Quote = "... shortening of the larval period and the reduction in the number of larval molts associated with an increase in parental age were not evident until the parents had aged at least 4 weeks, and the shortening of the adult stage until they had aged 6 weeks or longer ..." Quote from (1961) "Effects of Parental Age on Offspring from Isolated Pairs of the Mealworm Tenebrio molitor";

    And furthermore: "... Mated females lay their first eggs on the fourth day and virgin females about 1 day later. After the sixth day, mated females matured oocytes at about the same rate as before this time, whereas oocyte production is almost completely inhibited in virgins. Mated females also laid about 7.5 times as many eggs ...." See this abstract (1975) "REPRODUCTIVE BEHAVIOUR AND PHYSIOLOGY OF TENEBRIO MOLITOR (COLEOPTERA: TENEBRIONIDAE): II. EGG DEVELOPMENT AND OVIPOSITION IN YOUNG FEMALES AND THE EFFECTS OF MATING"; ---- And you might want to get the free full pdf clicking on upper right of this link for (1996) "Vitellogenesis in virgin and mated females of the mealworm beetle, Tenebrio molitor";

  • Thanks, @gringojay, very interesting your references. However, I wonder if from the point of view of productivity would be desirable to establish an age limit for breeding adults or keep until they die naturally go ?.

  • @edepro53 - if you are trying to run a systematic/predictable breeding operation, you'll end up limiting the breeding period to a pre-determined window to keep your cohorts on-schedule. Otherwise you can just have them breed continuously

  • When you treat the egg shells to make the calcium bio available, could this also be applied to snail shells? I am starting snail meal for poultry, and have a lot of left over shell. this would be african land snail if it makes a difference. Curious if the shells of snails (cleaned by means of heat) could be used in similar fashion as egg shells?

  • Calcium carbonate is the same & can be accessed by the same chemistry from snail shells & sea shells & egg shells.

  • Does anyone know if there are any issues using cassava/manioc as a water source. They contain harmful calcium crystals as I understand so it is commercialy harvested prior to harvested and always cooked prior to eating. Not so unlike taro or potato. Beacause I am in the tropics, potatoes do poorly and taro beds huge amounts or irrigation to grow, so both as not sustainable/efficient options. Same for carrots. Sweet potatoes and cassava are great options on the other hand. Sweet potatoe requires much more water compared to cassava, so it would seem to make sense to use cassava over sweet potato in order to use less fertile land for eventual protein production and also because sweet potato is considered by most be to more delicious and is thus more marketable, leaving only discard sweet potato available for animal feed. But I'm not sure if raw cassava will pose risks as a mealworm, or other insect program, moisture source? I have seen in Philippines and some other countries using cassava as a binder for fish feed but I know they have not thought about potential health risks in their endeavours, simply that it's a great sustainable binder product to replace clay. But is it safe?

  • I haven't read through 5 pages of comments but I have to say the whole premise of breeding in a bag is so flawed its barely worthy of discussion.
    No means to clean it (ever tried drying a plastic bag - its hard to get all the water droplets out). No means to sterilize it with heat (ever seen plastic in very hot water?).
    You need a shelf to put it on if you're going multi-level and you can't have much production without going mutli-level, so why not just use a drawer?, How do you sift stuff in a bag?
    I could go on and on. Ever seen a commercial facility use bags? Neither have I.
    Plastic is the obvious choice. Its relatively inert, easy to clean if there are no crevices or sharp angles, resistant to fairly high heat for sterilization and can be easily incorporated into a drawer, multi-level system. And its way cheaper and more rugged than either stainless steel or glass. And can be molded into the exact shape needed. Of course nobody uses wood for obvious reasons.

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