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 Scientific Proof silkworms can harm your dragon.

So I wanted to write a post about Silkworm Disease. I want to do this because people really need to understand how important it is to keep these feeders clean. Most breeders or sellers of silks will NOT sit down and tell you the good bad and the ugly... Why? Because they care more about sales than the actual person buying their stuff. Once it leaves their hands and is fed off to someones reptile, they could really care less. If they come dead, they replace them, the buyer really never knows why they died, but just get new ones and feed them off to their pets without thinking twice. TRUST ME when I say this.... There IS a reason they died, but they won’t tell you why they died. So please excuse this longggggggggg post. But I believe EVERYONE should really try to follow along, take the time to read it and you will learn a lot. So with that let’s begin....
Silkworms by far one of the hardest things to raise for someone that does not pay attention to detail on how to care for them. Have you ever ordered a batch of silkworms that came moldy on top of food? Have you ever noticed Silkworms dying off for no apparent reason? Do they look like the have flattened out and started hanging over things, turning different colors etc? If you have and you fed your reptile these disease infested silks, I would suggest you do get a professional fecal done at a vet that can test for something called Gram Negative Rod in your reptile as soon as possible. The people over the internet can not test for this in a fecal. It is very expensive equipment and no one in (groups) has the ability to do this test or the equipment.
The fact is, Silkworms are HIGHLY prone to bacterial infections from not caring for them properly. Some people think that there is no harm in them, some people don’t even know that these things DO exist. But I am here to try to educate you a little about what I know and what I have learned in this process. There are several diseases silkworms can get, and there are also symptoms to look out for. Let us go through some of these so you can get a better idea of just how serious this all can be.
Silkworms writhe/flip back and forth and vomit gut juice.
This is caused by INSECTICIDE on mulberry leaves. It is a very sad way for silkworms to die. If you are unable to ascertain whether a mulberry tree has or has not been sprayed please batch test the leaves with only a few silkworms first. If the leaves are sprayed the silkworms will show symptoms within 6 – 12 hours of eating the leaves depending on the potency of the insecticide residue on the leaves.
Problem: Worms appear lethargic and flaccid, growth is stunted. The cephalothoracic region may be translucent. Worms vomit gut juice (green to brown yellow), develop dysentery and excrete chain type fecus. Dead worms putrefy quickly often with a foul odor. The colour of dead worms is black/brown, if you try to lift a dead worm it will break open. Dead worms break open when healthy worms walk over them covering the healthy worms in fluid.
Name and Cause: Flacherie: Bacteria and viruses cause the disease individually or in combination. Flacherie is most often caused by high humidity and fluctuating temperatures. Flacherie is also caused by mold, fermentation and humidity build up in waste mulberry and frass. It is most often seen in the 4th and 5th instars but can occur in the earlier instars. If your silkworms get infected during the 3rd , 4th or early 5th instar, symptoms of the disease will be observed prior to spinning or pre-pupal stage. If the infection is in the late 5th instar, the mortality will be in the pupal stage in which case your cocoons will not hatch, this is most often identified by your cocoons emitting a foul smell. Changing from coarse Mulberry to tender Mulberry leaf favours the disease development especially if the change is made abruptly after feeding coarse leaves for sufficiently long time.
Solution: As Flacherie is most often contracted in the early Instars and does not present until the later instars it is usually impossible to eradicate without destroying the entire colony. You may remove the sick or dead silkworms and any silkworms that have contacted fluid. Wash hands carefully before handling healthy worms. Dispose of dead or sick worms by either burying 2 feet or more underground, double bagging and placing in the outside rubbish bin or by burning.
If you choose to destroy the whole colony place all worms in a bag and place into the freezer.
What are the symptoms of flacherie ? Bacteria and viruses cause the disease individually or in
combination. Fluctuating temperature and humidity and poor
quality mulberry predispose the disease development.
1. The diseased larvae will be stunted in growth, dill
lethargic soft and appear flaccid
2. The cephalothoracic region may be translucent
3. The larvae vomit gut juice, develop dysentery and
excrete chain type fecus.
4. The larvae on death putrefy, develop different and emit
foul smell.
161 What is Thatte roga and how it is caused? 1. Thatte roga is a type of flacherie in silkworm
2. It is cause by streptococcus sp. And or Staphylococcs
sp of bacteria in association with infectious flacherie
3. These pathogens are releases into the rearing
tray/platform by diseases larvae along with feces and
4. The released pathogens contaminate the rearing tray,
platform and the mulberry leaf I the bed. They survive
in the rearing tray/platform for long time and cause
disease if they are not disinfected effectively.
5. They cause the disease in larvae that re reared in the
contaminated tray. The rate of disease development
depends on the temperature and humidity in that
particular tray.
6. The bed temperature and humidity will be high in the
tray in which there is accumulation of feces, wasted
leaves and poor air circulation. Such conditions are
suitable for the bacteria to multiply in the larvae and
rearing bed.
7. In presence of virus in the larvae and high temperature
condition, the disease development will be faster.
8. As the infection takes place in the particular
contaminated tray and develops bases on the
environmental conditions in that particular tray, the
disease is noticed. In the tray and later spread to other
trays through secondary contaminations.
Problem: Silkworms are sluggish with swollen intersegmental region, The integument of diseased larvae are fragile and breaks easily, a milky fluid oozes out from the larval body, the diseased larvae do not settle for moult and show
shining integument, the larvae appear to be restless, the dead larvae hang by hind legs head downward. Basically if your worms will not spin and just die, this is the cause. In silkworms infected with a high dose of virus, the ecdysone hormone required for moulting and maturation will be destroyed. The larval period will be simply continued indefinitely due to lack of ecdysone till the larvae develop the disease. This is why we see the disease associated with worms that fail to moult and spin their cocoon. If the infection level is low, larva pupate will die in pre-pupal or pupal stage. How Grasserie diseases silkworm larvae look
like ?
The Grasserie disease is caused by a virus – Nuclear
1. The larvae will be sluggish with swollen intersegmantal
2. The integument of diseases larvae will be fragile and
brakes easily
3. On infury milky fluid containing many polyhedral
inclusion bodies oozes out from the larval body
4. The diseases larvae do not settle for moult and show
shining integument
5. The larvae appear to be restless
6. The dead larvae hand by hind legs head downward
Name and Cause: Grasserie: The Grasserie disease is caused by a virus – Nuclear polydedrosis. Grasserie is similar to Flacherie in that poor hygiene and poor Mulberry Quality contribute as well as humidity and temperature fluctuations. Avoid high ( 28-35C), low rearing temperature ( 10-20 C) and rearing humidity ( <70%). As for Flacherie.
Solution: As for Flacherie.
Problem: The diseased silkworms prior to death will be lethargic and on death are flaccid, oil specks may be seen on the surface of silkworms, they gradually become hard, dry and mummify into a white or green coloured structure. The diseased pupae will be hard, lighter and mummified.
Name and Cause: White Muscadine is caused by a fungus Beauveria Bassiana and the Green Muscadine is caused by a fungus Spicaria Prasina. Aspergillosis is common in young age Silkworms and the infected larvae will die. Dark green ( Aspergillus Flavus) or rusty brown ( Aspergillus Tamari) Mycelial cluster are seen on the dead silkworm body. Caused by the fungus being present on the mulberry leaf transported there by other insects.
Solution: Hygiene. Prevent Humidity build up. Keep mulberry tree’s free of insects (without the use of insecticides as this will kill your silkworms). Muscardine is common in winter and rainy seasons because these seasons provide favourable environments for infection, growth and multiplication of the pathogen.
This type of dead Silkworm is the source of the traditional Chinese Medicine “bombyx batryticatus” or “stiff silkworm”. It is the dried body of the 4~5th stage larva of silkworm died of the white muscadine disease which is caused by the infection of the Beauveria bassiana . Its uses are to dispel wind, dissolve phlegm and relieve spasm!
Muscardine and Aspergillosis:
This is a fungal disease caused by Beauveria bassiana and Aspergillus flavus, A. oryze and A. tameri. Fungal disease in silkworms is caused mainly through cross infection. Initially the infected larvae appears normal and do not show any external symptoms. As the disease spreads, the feeding rate reduces and larvae go below the bed. The body become flaccid and soft, after death, the fungal conidia grow on the body surface and larvae become hard like white chalk. If the infection is during the fifth instar, the larvae spin the cocoons, but die inside the shell. Aspergillosis infected larvae also show the same symptoms of white muscardine but on death of the larvae, they turn green in colour.
Generally fungal disease is seen during rainy season but incidence is very high during winter. High temperature and humidity required during chawki stage is also highly congenial for fungal spores to multiply. Therefore,chawki stage is also highly congenial for fungal spores to multiply. Therefore, care should be taken in observing the worms frequently.
Pébrine is a disease of silkworms, which is caused by microsporidian parasites, mainly Nosema bombycis and to a lesser extent Variomorpha, Pleistophora and Thelophania species.
The silkworm larvae infected by pébrine are usually covered in brown dots and are unable to spin silkworm thread.
How the silkworm larva infected with pebrine
looks like
Pebrine is a disease caused by a parasitic microsporidian,
Nosema bombycis Nageli
1. Diseases larvae show slow growth, undersized body
and poor appetite.
2. Diseases larvae reveal pale and flaccid body. Tiny
black spots appear on larval integument.
3. Dead larvae remain rubbery and do not undergo
putrefaction shortly after death.
Black thorax Septicemia :
Causal organism : Bacillus spp.
Seasonal incidence : The disease prevails during April-July
· Swollen body.
· The thoracic region of the infected worms become blackish, body shrinks.
· Excretes soft and liquid like excrements, rotting of the body follows with excretion of dark brown fluid.
· Sluggish movement and low appetite.
· Immediately after death, the thoracic region becomes black.
Source of infection : Through wound injury
Pre disposing factors: Mishandling of worms during transfer.
Control/prevention measure:
· Maintain hygienic condition in and around rearing room.
· Avoid injury to the leaves.
· Avoid overcrowding and accumulation of faeces in the rearing beds.
I know that this is a lot to take in, and there is so much more information that goes along with this that I will try to touch base on more often. The silkworm industry is very deep, so deep there is so much more to learn and find out still. But what I do know I want to educate the people I feel should know about it. YOU! Some people might think I’m crossing lines here by putting out this information, but I believe it is in EVERYONE’S best interest to know these things, buying from me, buying from anyone else. I’m still working on proving that indeed these bacteria’s can be transferred to your reptiles. Especially Bacterial infections. I want you to know, I do have someone helping me figure all of the details out. But will leave you with an interesting read that is helping me get closer to proving this. No one want’s sick animals. No one selling silkworms should be ignoring these issues, and just replacing dead worms! It is something we all need to be aware about for our pets safety. This post might upset some people that sell silks, but I feel it is MY duty as a human being, a reptile owner to pass this information along to you.
If you have made it to the end of this, I hope you have learned something new. I hope you will always look out for diseased silks, and be able to identify what possibly could be wrong with them, and why it happened. Now for what I have found, that PROVES that these types of bacteria can pass to our pets is an is of an actual research. I ended up having a dragon test positive for Gram Negative Rod. I started researching, having feeders tested, and asking a lot of questions. Learning about things is never a bad thing. Trying to piece it all together can be very difficult. I’m still in the process and has taken me a very long time. But if you notice anything odd in your reptile. Please make sure they test for Gram Negative Rods. It could save their life! I will write more about things in this industry that people don’t really want you to know about in future posts. This is why I stress the "Clean" part of raising silkworms... It is DIRE to do so because of the fact it causes illness not only in the worm. But in your pets as well. Here is the reading. Thank you so much for taking the time to read this entire post. The last thing I want to do is scare anyone away from a healthy feeder because of what other people have done to them. You now have the control to take care of them the proper ways, know what to look out for and ensure your animals safety. That is what is most important here. Link I’m sure we all know by now the Mulberry Farms has had bacterial issues in the past and has stated that they were not aware of silks getting animals ill. Also Mulberry Farms has a patent on silkworm chow and run the industry together with Coastal.

06/18/15  07:39pm


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  Message To: Someonewhocares   In reference to Message Id: 2313961

 Scientific Proof silkworms can harm your dragon.

Well thanks for the link at the end ...

We purchased silks many times and even raised them to cocoon and hatch ... But we failed more than we succeeded. We thought it was just us. I see in your article the symptoms that caused it. We even had our own Mulberry tree. Freshly washed leaves. I remember when the Grasserie virus struck the industry .......
we knew about this in 2004

Thats why we raise roaches for personal use instead. Silks are just too difficult.


06/20/15  12:58pm


Dragon Lover
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  Message To: Cphill58   In reference to Message Id: 2313976

 Scientific Proof silkworms can harm your dragon.

I raised silk worms for many years before the virus. Once it hit, I could never do it again. I knew all along it was because of the virus. My dragons never got sick. Of course, I would only feed the healthy ones and discard the gooky ones.


07/01/15  06:01pm


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  Message To: Dragon Lover   In reference to Message Id: 2314121

 Scientific Proof silkworms can harm your dragon.

Issue is they can look healthy and be infected and not show any symptoms until later instars. So what you think is healthy may not be :(

07/09/15  09:52am


Dragon Lover
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  Message To: Someonewhocares   In reference to Message Id: 2314184

 Scientific Proof silkworms can harm your dragon.

Very true!!!!

They’re still alive 6 years later, so I got lucky..


07/13/15  06:07pm

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