Parasitic oe?

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This topic contains 15 replies, has 5 voices, and was last updated by  littlecritter 5 years, 9 months ago.

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  • #36442

    jillian
    Participant

    I have about two dozen chrysalises and five caterpillars on swan plants on my back porch. The first two went dark and then both butterflies have had stunted wings and not been able to fly. I put them in the freezer, feeling very bad.

    All the caterpillars were raised on the same plants. Can I expect them all to be affected in the same way? As well as the five remaining caterpillars and the few eggs that I have just noticed on the plants?

    What to do? If the creatures are infected I take it that the plants are as well. Please advise how to treat them so that I can start afresh.

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  • #37178

    littlecritter
    Participant

    Hi Norm

    Thanks for the helpful advice. It is a shame I didn’t catch the decline of the caterpillar and only found it once it had died, however now I’m on alert I will be able to monitor the situation better should it happen to other cats . Hopefully it is a one off and is the result of a predator rather than the result of a virus or bacteria, however as a first time monarch butterfly breeder I am much more informed than I was a day or two ago, so some good has come out of it.

    #37159

    NormTwigge
    Participant

    littlecritter – Oe does not usually affect caterpillars to the extent your photo shows, most damage occurs at the pupal stage, thus affecting the resulting butterfly. The dead caterpillar could be from a viral or bacterial infection, so keep an eye on the others. Your description of “deflated looking” could also point the finger at a spider, as some species of spider suck the contents from the caterpillar for a meal. A soldier bug will also do the same.

    #37151

    littlecritter
    Participant

    I have just discovered a dead caterpillar and I am concerned it may be OE, I have included a photo of the poor old cat below:

    Caterpillar infected with OE?

    Any thoughts on possible cause of death would be appreciated.

    There were 7 (seemingly) healthy cats on the same plant. I have disposed of the plant and moved the healthy cats to another plant. I will monitor them closely as advised on this forum post.

    The plants are in pots in my garage so aren’t exposed to pests such as wasps although there is a healthy population of spiders in the garage.

    #36595

    Jacqui
    Moderator

    Me again!

    Looking at that website I quoted earlier:

    “Some emerge fine but cannot expand their wings properly. Their wings dry crumpled, leaving them unable to fly. Some look normal but are weak. When that happens, most people assume that the butterfly has OE. This is a dangerous assumption. If the emerging butterfly does not have OE, it may have a disease or other issue causing the problem. Simple dehydration from being indoors can cause the exact same scenario. If you don’t know for sure whether the butterfly has OE and you assume it is OE, you are leaving the door open for it to continue happening again and again.”

    and

    “Adult butterflies can be checked for OE by placing a piece of CLEAR tape firmly to its abdomen, removing the tape (which now has scales on it), placing the tape on a microscope slide, and looking for OE spores.”

    Oe spores look like this:

    http://www.monarchlab.org/Lab/Research/topics/Enemies/images/spores-600w.jpg

    The OE spores are the smaller brown ovals. The scales from the wings are the larger surfboard-like shapes.

    #36591

    Jacqui
    Moderator

    Jillian – you ask “Is anyone able to test one to verify that it is oe that is affecting them?”

    Yes, tests can be done – but it does cost time and $$$.

    Whether or not it is Oe, the remedy is much the same. It all comes back to ‘hygiene’.

    Remember that diseases, parasites, predators (etc) are all Nature’s way of balancing the species. In the wild there should NOT be a predominance of Monarch butterflies. We humans are great at manipulating Nature to suit our own likes and dislikes… and we cause a lot of what we then see as ‘problems’.

    By wanting to have more and more Monarch butterflies in our garden but no wasps, mantises or other natural controls, we’re making our spaces a paradise for the unseen parasites which are here to control what Nature considers a ‘plague’.

    Phone me on 09 551 3383 and I’ll see if I can help you – or email me your phone number and I’ll ring you.

    #36586

    jillian
    Participant

    I came home today and found six butterflies on their backs on the floor apparently because they were too weak to cling and pump their wings up when they emerged. Their wings are now variously bent and folded so they probably won’t be able to fly. It is very depressing. Is anyone able to test one to verify that it is oe that is affecting them?

    #36558

    Jacqui
    Moderator

    Edith (in Florida) is currently revamping her website and this is the new page regarding Oe. Very easy to read up about it here:

    http://www.butterfly-fun-facts.com/disease-oe/oe-ophryocystis-elektroscirrha-monarch-butterfly/

    #36557

    Caryl
    Participant

    Jillian
    http://www.butterflyfunfacts.com/pupae-flaws.php
    I have found this link helpful. It shows deformed chrysalis and the effect it will have on the butterfly. I have had quite a few deformed ones, this I believe happened because the caterpillars in J form were affected by other caterpillars on the plant. Now I try to take the J’s inside to prevent this happened. I have had more than 50 hatched in 12 days and am very happy with this outcome. The bleach solution can be 10%. I used that last year on a plant, removed all caterpillars, treated the plant a couple of times, didn’t rinse and it was restored to health. I think I took many of the leaves off and cut the plant back a little. Good luck and let us know how this works.

    #36556

    jillian
    Participant

    Hi Norm

    Thanks for your helpful comments. I have got off to a bad start this year with lots of deformed butterflies. I will disinfect my plants (in pots on the porch) and hopefully start afresh.

    #36504

    NormTwigge
    Participant

    Hi Jillian, I am not an expert with the sanitising of milkweed plants, but from what I’ve read some use a 5% bleach solution sprayed onto the plant and left for a minute or two, and then flushed off with plenty of water. Left any longer and the bleach may affect the leaves. I would try one plant first. Sanitising monarch eggs is a fairly common procedure with butterfly farmers to ensure healthy stock, and the following seems to be well used recipe:
    Cut off the pieces of leaf containing the egg. Mix 1 tablespoon (or other measure) of bleach with 19 tablespoons of water and soak the eggs for 60 seconds, no longer. Remove the eggs from the solution and rinse in fresh water for at least one minute, until there is no chlorine smell. Its possible the odd egg may separate from the leaf, so strain through a piece of curtain or muslin to catch them. Place on a paper towel to dry. When dry any loose eggs can be placed in a container with some fresh cut leaves for the emerging caterpillars to feed, and then transferred back to the plant. Leaf pieces still containing the egg can be positioned on the plant (presumably they are potted)
    and the emerging caterpillars will transfer themselves onto the plant.

    #36483

    jillian
    Participant

    Hi Norm

    Thanks for your comments. Subsequent butterflies either haven’t been able to emerge or have emerged with wings that don’t expand, so I’m guessing my three porch plants are all heavily infected.

    I am going to make a 5% solution of bleach and spray all the plants, removing the remaining caterpillars and chrysalises, for whom I have no hope, first. I have a couple of questions about this process, though. Is 5% too weak/strong?

    Once the plants have been sprayed, do they need to be rinsed off with the hose before they are suitable for new eggs to be laid on them?

    I notice I have eggs on some leaves – should I leave these on the plant to be sprayed, or remove the leaves and, once the caterpillars have hatched, put them back on the same plants, or put them on other plants?

    I look forward to your advice.

    #36447

    NormTwigge
    Participant

    If the eggs are laid by a monarch infected with O.e. then the exterior of the egg will have O.e. spores. Also infected adults will spread the spores on to the foliage as they flutter around the plant. When the the emerging caterpillar eats the egg shell it will ingest the spores and infect the gut. The caterpillars droppings will then infect the foliage and be passed on to other caterpillars that eat the foliage. This is why commercial breeders of monarch butterflies wash the eggs briefly in a bleach solution to kill O.e. spores without affecting the eggs.
    O.e. is a common disease among monarch populations and varies in intensity, and they live with it, but it is only when is gets intense that it causes problems.

    #36446

    Caryl
    Participant

    There are different opinions on using bleach and variations from 2% to 10% bleach in water. It worked for me. You could also cut that plant back, removing all leaves and let it grow again….. from a source on the web:

    “Can you use a bleach solution to cleanse Monarch eggs of OE? How safe is this and is it effective?

    This approach is NOT recommended as bleaching the eggs has NOT been found to be a satisfactory method of elminating OE. The concentration of bleach needed to kill the OE spores can also damage the egg chorion. A method to try to rescue some potentially contaminated eggs is to remove them from the Milkweed they’re on (the contaminated Milkweed) and transfer them to a clean Milkweed leaf. This will reduce the potential number of spores the caterpillar might ingest.”

    #36445

    jillian
    Participant

    Hi Monarch lover

    Thanks for the advice. What should I do with all the other chrysalises, do you think? Allow them to take their course and hope for the best? Or can I spray the plants with the bleach solution with the chrysalises on them?

    I am not familiar with the use of bleach – when you say a weak solution, what are the proportions of bleach to water?

    #36443

    Caryl
    Participant

    Hi Jillian, Sounds like OE. There may not be spores on all the leaves. What I did with the same scenario was to remove the caterpillars on the affected plant and take them to another plant which has no other caterpillars on and watch them closely. My ones did fine, then I sprayed the affected plant with a weak solution of bleach and water and it grew again with no further problems. I now spray with a weak bleach solution all the new plants I get. It does not hard any eggs on them. It’s sad when butterflies don’t make it.

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