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Discussion Starter · #1 ·
This is copy job of Dr Danny Brown's web site
He is one of leading minds in Australian geckos as well as a private breeder of many reptile species of which he has an impeccable reputation
In other words not to take his advice would be irresponsible

This is a link to his site if anyone wants to check it out Danny Brown's Home Page
Thanks Geckoman

The Pro’s and Con’s of Mealworms as a food for reptiles
By Dr Danny Brown BVSc(Hons) BSC (Hons) MACVSc (Avian Health)

For many reptile keepers, supplying a reliably available source of live food for their insectivorous reptiles is a challenge. This means that many rely of what is available with an expectation that it is also good nutritionally. Unfortunately that is not always the case.
Mealworms are the larval stage of a beetle (Tenebrio molitor). Whilst availability and ease of culture are their major advantages, they fall very short in many ways.
The nutrional content of the average mealworm is as follows

Edit: this table does not work to check it out follow this link : http://www.geckodan.com/The Pro.htm

The primary issues to consider are the lower protein levels, higher fat and appalling Calcium:phosphorous ratios. Please note that from a Ca:p point of view, crickets are no award winners either but at least they have some things going for them.
The ideal Ca:p ration is 1:1.3. The reason we get so hung up on Ca:p ratios is that the body determines how much calcium it needs to absorb based on phosphorous levels in the blood. In a situation like we see in the mealworm, not only is very little calcium available, but the body is tricked into thinking it doesn’t need it by the gross imbalance of phosphorous.
There are ways that we can attempt to improve Calcium levels (but we can’t reduce Phosphorous levels). Dusting of the mealworms with calcium powder prior to feeding is not terribly efficient as the shiny exoskeleton does not hold a lot of it for any length of time.
Gut loading (or feeding calcium to the mealworm prior to feeding it to the animal) has its limitations. Primarily, the higher the calcium content of the “gut load”, the more unpalatable (and often metabolically toxic) it is to the mealworm. Secondly, the gut size of a mealworm is such that improvements are at best marginal.
How the mealworm is bred also has its issues.
Phytic acid or cereal phytates are concentrated in the aleurone layer of the seed coat of all cereal grains. This is third outermost layer of the seed coat (2nd is the testa, 1st is the pericarp). These three layer are what makes up the product we know as bran once processed. Cereal phytates have the property of being able to immobilise dietary calcium and magnesium i.e the phytates bind to calcium and magnesium and form insoluble complexes that are not readily absorbed. Calcium is therefore not removed from the reptiles body BUT it is prevented from entering the reptiles body in the first place. When we consider that mealworms are very low in calcium in the first place it is safe to consider that virtually none of this will be available to the reptile if the mealworm also has a gutful of phytate rich cereal bran when it is fed to your reptiles. Not all cereal grains have the same level of phytates in their aleurone. The highest levels are found in oats, followed by barley, rye, wheat and lastly millets.
In order to feed our mealworms (and maggot cultures) on a substrate that has reduced phytate levels is to therefore prudent to use a cereal based product not made from the seed coat. Two products are recommended. Pollard (or wheat fines) are processed from the endosperm (the starchy central part of wheat) and therefore have significantly reduced phytate level. The disadvantage of pollard is that many manufacturers produce it very fine which makes it (in my hands) too “gluggy” for maggot substrate BUT excellent for mealworms as it is easier to sieve. In addition, on a personal note, I do not suffer from hayfever when working with pollard but I most certainly do with bran. Some manufacturers produce a coarse pollard which is excellent for both purposes. Mill Run is an alternative product which has a coarseness suitable for both maggots and mealworms. It is made up of coarser pollard with remnants of bran. I use is by preference as its texture is always ideal for maggots, it has about 6% more protein than bran (which is essential protein for use by the mealworms or maggots) and it doesn’t flare up my hayfever.

In addition to the calcium issues, the high fat content of mealworms has obvious disadvantages.
The tough exoskeleton of the mealworm can be difficult to digest and impactions of the gut from undigested mealworm skins is not uncommon. This can be partly alleviated by only feeding very small mealworms or by feeding “white” (freshly shed) mealworms.

My usual recommendation is that mealworms should comprise no more than 10% of the diet and that it is better to feed them smaller rather than larger.
 

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I think most people knew all this already hard shell high and high fat content but the way I look at it high fat content can be an advantage if your reptile is under weight.
As for being hard to dust with calcium which takes up most of this letter has this guy never heard of Komodo Cricket Dust Calcium Carbonate Powder this stuff will stick to any thing and is not coming off untill long after they have been eaten.
So really just leaves you with the hard shell issue and I think if your rep is being kept at the correct temperatures and is healthy it shouldn't have to problem with a bit of hard shell.
I agree not the best live food for your reps but don't take it to far : victory:
 

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Discussion Starter · #4 · (Edited)
I think most people knew all this already hard shell high and high fat content but the way I look at it high fat content can be an advantage if your reptile is under weight.
As for being hard to dust with calcium which takes up most of this letter has this guy never heard of Komodo Cricket Dust Calcium Carbonate Powder this stuff will stick to any thing and is not coming off untill long after they have been eaten.
So really just leaves you with the hard shell issue and I think if your rep is being kept at the correct temperatures and is healthy it shouldn't have to problem with a bit of hard shell.
I agree not the best live food for your reps but don't take it to far : victory:
No we don't get Komodo products in Australia as far as i know, is it a finer grade to the other leading brands of reptile calcium?
I think the main issue i was pointing out is the fact that if raised on bran then the mealworms can inhibit calcium absorption
Your right in saying that at the correct temperatures it wouldn't be impossible for them to digest it, but not all keepers have strict temp controls in place do they.
I guess what im trying to say is that there is much better alternatives and that using mealworms as a staple would be like us living of cheese burgers.
If your reptile is under weight then sure it would help them put on wieght but healthier results can be achieved with a high protein diet such as roaches, silkworms, pinkies (for dragons) etc
 

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Discussion Starter · #5 ·
I might just add that i do use mealworm pupae as a treat for my geckos (as you can see in my avatar lol)
 

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No we don't get Komodo products in Australia as far as i know, is it a finer grade to the other leading brands of reptile calcium?
I think the main issue i was pointing out is the fact that if raised on bran then the mealworms can inhibit calcium absorption
Your right in saying that at the correct temperatures it wouldn't be impossible for them to digest it, but not all keepers have strict temp controls in place do they.
I guess what im trying to say is that there is much better alternatives and that using mealworms as a staple would be like us living of cheese burgers.
If your reptile is under weight then sure it would help them put on wieght but healthier results can be achieved with a high protein diet such as roaches, silkworms, pinkies (for dragons) etc

Thanks very much for the link and info posted here. I have said several times here about the dangers of using bran/cereal filled feeder insects, but always seem to be ignored. Cereals are fine when mixed with fruit/veg for growing insects but I like to give my insects only veg/fruit for a couple of days before using as feeders. I use calypso too it is good but I doubt any better than any pure calcium dust you get in Australia.

The problem re phosphorus/cal ratios is compounded by the fact very few reptiles get the UV levels they would in the wild.

I never eat cheeseburgers !
 

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but not all keepers have strict temp controls in place do they.
then they should address this matter, whether or not they feed mealworms
 

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Discussion Starter · #9 ·
I only posted this info for people to make informed decision when feeding their herps, not to judge peoples knowledge or husbandry or start an argument
I urge people not to be like sheep and take peoples word for things but rather do there own research
 

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I only posted this info for people to make informed decision when feeding their herps, not to judge peoples knowledge or husbandry or start an argument
I urge people not to be like sheep and take peoples word for things but rather do there own research
thanks for the info cirtainly gives me somthing to think about
 

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The tough exoskeleton of the mealworm can be difficult to digest and impactions of the gut from undigested mealworm skins is not uncommon. This can be partly alleviated by only feeding very small mealworms or by feeding “white” (freshly shed) mealworms.

I've just seen this post, and to be honest, a couple of things need mentioning (I think).

Firstly, the nutritional values table is not referenced. Where is the data from, and based on what (sample size, species, weight measure (dry / wet), method of testing... the list goes on). This is not to say the values are inaccurate, but without referencing the source then they are totally unreliable. They look roughly right compared to other published estimates I have seen, but this isn't great evidence.

Secondly, the paragraph quoted above is completely untrue. The chitin content in mealworm larvae is highly comparable to that of numerous cricket species, as is seen in the link below (from the original source):
http://glasgowgecko.co.uk/Articles/Chitin.pdf

If people experience problems with the digestion of mealworms then attention should be directed at problems with basic husbandry (temperature, parasite burden etc...), which can not fairly be directed at the feeder insect.

Thirdly, the size of the digestive tract, again I'd love to see some evidence of this.

Finally, whilst they are right to suggest problems with the diet of commercially raised mealworms, with the ease that this species breed. This really doesn't have to be a problem.

I do not question the expertise of the individual that has written article, however without proper references its just opinion. Whether or not people decide to use mealworms as a feeder or not will be based on a few things, but it is essential that all the facts are available.

Andy
 

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Discussion Starter · #13 · (Edited)
I've just seen this post, and to be honest, a couple of things need mentioning (I think).

Firstly, the nutritional values table is not referenced. Where is the data from, and based on what (sample size, species, weight measure (dry / wet), method of testing... the list goes on). This is not to say the values are inaccurate, but without referencing the source then they are totally unreliable. They look roughly right compared to other published estimates I have seen, but this isn't great evidence.

Secondly, the paragraph quoted above is completely untrue. The chitin content in mealworm larvae is highly comparable to that of numerous cricket species, as is seen in the link below (from the original source):
http://glasgowgecko.co.uk/Articles/Chitin.pdf

If people experience problems with the digestion of mealworms then attention should be directed at problems with basic husbandry (temperature, parasite burden etc...), which can not fairly be directed at the feeder insect.

Thirdly, the size of the digestive tract, again I'd love to see some evidence of this.

Finally, whilst they are right to suggest problems with the diet of commercially raised mealworms, with the ease that this species breed. This really doesn't have to be a problem.

I do not question the expertise of the individual that has written article, however without proper references its just opinion. Whether or not people decide to use mealworms as a feeder or not will be based on a few things, but it is essential that all the facts are available.

Andy
In Australia we only have one type of cricket commercially available so he is comparing it to that( not sure on the species) .
The main point about the diet they are raised i thought that he was simply advising people to choose things like pollard as opposed to bran to raise their mealworms.

That article that you provided a link to clearly showed in a table that adult mealworms have close to TWICE the chitin as crickets, i think that is exactly what he was trying to point out

Your right though it is not referenced so really it does not come across as a convincing paper, but it is not intended for publishing in a science journal, it is merely part of his collection of care sheets he makes available to people browsing his website

I will do some research and try to get some papers to back up Dr Browns care sheet, if i cant find sufficient evidence then i will gracefully admit that the info could be wrong, but if i can provide some referenced proof then id expect u to do the same:notworthy:

I know i got a little defensive before but the main reason i posted this was to give people something to consider, not to tell them how to look after there herps.
People need to do their own research from multiple sources as everyone seems to have varying opinions in this industry
Thanks
 

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In Australia we only have one type of cricket commercially available so he is comparing it to that( not sure on the species) .
The main point about the diet they are raised i thought that he was simply advising people to choose things like pollard as opposed to bran to raise their mealworms.

That article that you provided a link to clearly showed in a table that adult mealworms have close to TWICE the chitin as crickets, i think that is exactly what he was trying to point out

Your right though it is not referenced so really it does not come across as a convincing paper, but it is not intended for publishing in a science journal, it is merely part of his collection of care sheets he makes available to people browsing his website

I will do some research and try to get some papers to back up Dr Browns care sheet, if i cant find sufficient evidence then i will gracefully admit that the info could be wrong, but if i can provide some referenced proof then id expect u to do the same:notworthy:

I know i got a little defensive before but the main reason i posted this was to give people something to consider, not to tell them how to look after there herps.
People need to do their own research from multiple sources as everyone seems to have varying opinions in this industry
Thanks
I think you have mis-read the paper I provided. Adult mealworms (the Beetles) have double the chitin of crickets, this is not the case for the mealworm larvae which are on the column before it. This point is clearly critical to understanding the message of the paper.

I'm not sure what you mean about being defensive however, my points are genuine concerns that I would have for any unreferenced search.

Andy

Andy
 
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