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Ophryocystis elektroscirrha - OE - Monarch Butterfly Parasite
Monarch butterfly, Danaus plexippus
Monarch scale without OE
Monarch Butterfly
Scale without OE spores
Checking a Monarch butterfly for Ophryocystis elektroskirrha, OE
checking a Monarch butterfly for OE spores through a microscope
Removing scales with clear tape.
Checking for spores.
A slide with Monarch scales on clear tape; used to check adults for OE, a butterfly parasite
A close view of oe spores on a slide
OE spores remain on the slide
after the tape is removed.
Check scales through the microscope
before removing tape.
Closer view of the same slide.
OE spores on Monarch butterfly scales, Ophryocystis elektroschrrha
OE spores on Monarch butterfly scales, Ophryocystis elektroschrrha
OE spores on scales and with scales
through a microscope.
OE spores closer view.
Spores of OE which are 'dead' from disinfection with bleach
OE spores that are 'dead' and cannot infect a Monarch butterfly caterpillar.
OE spores after being treated with bleach.
Light colored spores are dead.
Two OE spores, one may be alive. One is dead.
taped from checking Monarch butterflies for OE
Clean scales from a Monarch butterfly, seen through a microscope
Checking for OE can use a lot of tape!
This is what you want to see
through your microscope!
Monarch butterfly eggs, Danaus plexippus
A Monarch scale on a Monarch egg
Eggs can be removed by
gently rubbing a finger
across eggs after they have
dried for 24 hours.
This egg, seen through a microscope,
shows a butterfly scale.
When a caterpillar hatches, the first
thing it eats is its eggshell.
If a scale with OE is on the shell,
the caterpillar will ingest the spores
and WILL have OE.
A Monarch hatchling caterpillar eats its empty eggshell
Cleaning Monarch eggs to remove all traces of OE
A Monarch caterpillar just hatched and
immediately started eating its eggshell.
Deli cups are used to hold the sterilizing
solution and eggs for
the amount of time needed
to soak the eggs.
You can use any type plastic container for this purpose.
Cleaning Monarch eggs to remove all traces of OE
Cleaning Monarch eggs to remove all traces of OE
A large deli cup is cut to allow
water to flow through.
A smaller deli cup
has the bottom cut out.
A piece of sheer curtain material
is cut to use as a strainer.
The 'strainer' is assembled,
ready for the sterilizing solution
and eggs to be poured through.
Cleaning Monarch eggs to remove all traces of OE
Cleaning Monarch eggs to remove all traces of OE
Deli cups are used to hold the sterilizing
solution and eggs for the amount of time
needed to soak the eggs.
You can use any type plastic container for this purpose.
After the eggs have been rinsed
and laid on a paper towel to dry,
a fresh milkweed cutting is used
to pick up the sterile eggs and
place them into a container to hatch.

Cleaning Monarch eggs to remove all traces of OE
Cleaning Monarch eggs to remove all traces of OE
If you leave the eggs on the leaves, be sure
to allow them to drip dry
before sealing in a container.
The tote is marked to indicate which
Monarch laid the eggs being Disinfectd.
Note that eggs will often
detach from the leaves
and will be caught by the net.
Cleaning Monarch eggs to remove all traces of OE
Monarch hatchling larvae hatch in small totes in the egg laboratory
Use a screen fine enough for
hatchling caterpillar to be contained!
If you cannot find fine screening,
a piece of sheer material will work fine.
The hatching containers at
Shady Oak Butterfly Farm
are placed on a shelf until
the caterpillars have hatched
and grown for a few days.
Monarch without OE
Monarch with OE
A Monarch's abdomen should show clear
separation between white and black scales.
An Oe infected Monarch's abdomen
appears 'blurry', often with a
darker appearance than a
healthy butterfly.
Monarch butterflies with OE often cannot leave their pupal shell
OE infected Monarch chrysalises, pupa
A heavily Oe infected Monarch or Queen
will often become stuck in its chrysalis shell
and be unable to emerge.
A heavily infected Monarch chrysalis
will darken along its back first instead
of first showing color on its
orange wings as is normal.

OE is present in wild Monarchs. Farmers and others who raise
Monarchs, Queens, and Soldiers find themselves in a battle with nature.

Rearing milkweed in a closed greenhouse or screen house will protect your milkweed from wild butterflies who may leave spores on the leaves. When caterpillars eat these spores, they contract the parasite. If your milkweed is growing outdoors where wild butterflies are landing upon it, soak the leaves in 14 ml bleach and 386 ml water solution for 60 seconds. Rinse well and allow to drip dry but not dry out. Wet leaves are not healthy for your caterpillars.

A good microscope and clear tape are essential to check adult Monarchs for OE. Simply touch the CLEAR tape to the abdomen of the adult butterfly. Scales will stick to the tape and the adult will not be hurt. Breeder adults should always be checked before rearing their eggs to adult. If you do not have a good microscope, please send us a microscope slide with scales on clear tape and we will be glad to check it for you.

Disinfect your rearing containers, utensils, and tools between every set of caterpillars you rear! A dishwasher works fine. If your containers are too large for a dishwasher, use a 10% bleach/90% water solution and soak your container for 10 minutes before rinsing well.

Keep your counter tops sterile! Disinfect them after use.

To disinfect eggs:
1. Soak Monarch eggs in a solution of 14ml bleach and 386 ml water for 60 seconds.
2. Quickly remove them from the bleach solution and rinse well.
3. Lay the eggs/leaves out on a paper towel and cover with another paper towel. This allows them to airdry without possible contaminates landing on the eggs.
4. After they are dry (we wait till the next morning), place the eggs/leaves in a container with ventilation and add fresh food every day OR place the eggs on the towel in the middle of a milkweed plant. When the caterpillars hatch, they will crawl to the fresh food.

(Bleach can dissolve the eggs. Be sure not to use too strong of a solution or too leave the eggs in the solution for too long. Do a trial with a few eggs before sterilizing a large amount of eggs.) This dissolves the chorion (outer waxy layer of the egg) which could be contaminated with butterfly scales and OE spores.

There are two methods of bleaching eggs. One method is to simply cut the leaves and stems to fit into a small container. Add the bleach/water solution to the container with leaves and eggs already in it. The second method is to remove the eggs from the leaves. To do so, simply wait 24 hours after they are laid and gently rub the eggs with your finger. They will roll right off the leaves. Simply pour the bleach/water solution over the eggs in a container. After 60 seconds, we pour the solution through a piece of sheer curtain material. A net will often have holes much too large and the eggs will fall through. Some eggs will come off the leaves when you soak them, this is fine. Rinse well by placing the eggs into another container and soaking them a minute in clear water. Pour through your material again and allow the eggs and leaves to drip dry. Cover the eggs and leaves with a sterile paper towel to keep them clean until they are dry. Add fresh new growth leaves daily to the container in which you place the eggs. Removal of the chorion leaves the eggs susceptible to dehydration. Adding fresh leaves daily is a method of adding moisture without adding water. It also gives the babies fresh food to eat.

If you are rearing butterflies as a hobby, it is good to do your best to fight nature as you help nature. Try to keep parasites and diseases at bay for the butterfly's sake as well as for your sake! If you are having troubles, please email us. We will be glad to help all we can.

Often a parasite or disease infection or death isn't noticed in the garden because caterpillars tend to be eaten when they are not as fast or able to react as much as normal. A chrysalis in the garden is rarely noticed. In people's rearing containers, they are always noticed!

One of the first signs of diseases or parasites is loss of appetite. We notice this in humans also, when a child doesn't want to eat his/her favorite meal or dessert, parents become immediately concerned.

Signs of OE are brown chrysalises, Monarchs who have abdomens stuck in the chrysalis shell, Monarchs with wings which do not spread properly, caterpillars eating a bit slower than normal, chrysalises which do not 'color up' in the normal way, caterpillars which eat less or eat slower, and shorter life span of adult Monarchs.

A great website about OE is Monarch Lab .
If you are familiar with other websites with OE information, please share them with us.

We are often asked about problems from OE or Melt. When we share what we have learned, so many breathe a sigh of relief and comment, "Oh, I'm so glad. I thought it was my fault."
Once you learn about these parasites and diseases and start using the information to rear healthy caterpillars, you will enjoy rearing caterpillars in your home even more than before!
If you bring caterpillars in from your gardens, just do your best to use clean techniques. Remember, they may already be parasitized. This is NOT your fault!

Butterfly and moth diseases are purchased by gardeners,vegetable farmers, forestry services, and more. Parasitiods are purchased by the hundreds and thousands and released in nature. Since none of us like to take a bite from an ear of corn and find half a caterpillar left, we can understand why farmers tend to use diseases and other sprays. In most cases these diseases are species specific and will not harm butterflies in your yard.

If you do not own or have access to a microscope, please feel free to send a tape with scales from your Monarchs to our farm. We will be happy to use our microscope and email or snail mail you our findings.
OE Tape
Shady Oak Butterfly Farm
12876 SW CR 231
Brooker, FL 32622

Note; Monarch butterflies do have have a 'cocoon', the larva (caterpillar) will change into a pupa (chrysalis).