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Drone Bee
Mar 27, 2009
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Birmingham UK
Hive Type
Number of Hives
8 ish
The 'tutor' in our club insists I feed Fumidil-B in syrup as soon as I give up hope of honey and remove any supers.

Does anyone have any experience with this treatment and how well it works.

My understanding is that the bees don't necessarily eat the syrup from say an Ashworth feeder, they just store it in the bb, and probably (possibly) consume it during the winter months.

I believe this is a treatment for Nosema. Are there any alternatives ?
I've certainly experienced bees not feeding from ashworth/miller feeders in the past - never found out 'why' this was.

I always use contact bucket feeders as they don't appear to suffer mould so much as can go in the dishwasher after use.

As far as I know, this is the only treatment recommended for nosema in the UK. I've fed it in the past, but never seen Nosema in years when fed or when I forgot !
Apparently, Funidil-B is no longer being manufactured but existing stocks are still available for purchase....from what I've heard anyway.
There was a problem that it's certification as a permissible medicant lapsed earlier this year but apparently it is now licensed again. Haven't heard anything about manufacturing, though

Regards, RAB
It won't work at all if the bee's have bad nosema,you need to spray them on the comb,bee's do not like fumidil in syrup at the best of times,and are sometimes reluctant to take it. yes it does the job on nosema,but so does thymolised syrup,and another couple of feed additives are supposed to be okay,but i've not tried them.
There is nothing that kills off Nosema.

The spores can not be killed by Thymol or and Funidil-B.

Is it wise to give fumidil as a matter of course even if no symptoms? Isnt it like antibiotics pre infection - just builds up resistance and no use to the healthy bee.
Bcrazy, the spores are not killed,but they can no longer replicate,therefore the disease is stopped.Nosema is a fungi,thymol is a very strong fungicide,similar strength to phenol.
I think Thymol is a Phenol.
Long time since I did the chemistry books.
Same group,but the one i'm refering to would be carbolic acid,is that the same
I have just cheated and used Wiki ;)

I can't explain it so well:

Phenol, also known as carbolic acid, is a toxic, white crystalline solid

The word phenol is also used to refer to any compound that contains a six-membered aromatic ring

We are both right.
There have been many discussions about how to treat for Nosema.

I would like to try and explain what’s what regarding the treatment of Nosema.

The only successful drug found so far is the antibiotic fumagillin and marketed for beekeepers under the name Fumidil B.
This anti biotic will suppress the infection rate for bees and used in the autumn a feeding of about 200mg of fumagillin in 4.5 or 9 litres of syrup is fed to each colony and any infection being treated at the time, there will be a noticeable difference in the spring.
Severe infection use up to 400 mg per colony is recommended.
When treatment is used in the spring this anti biotic prevents the usual build up of infection and the treated colonies will produce significantly more brood and honey than other colonies fed syrup only.

Individual bees are crushed during an examination and then removed by other bees, which in turn will ingest the contaminated remains. This will aggravate the infection and probably explain the high incidence of Nosema apis in “package bees”.

The most dangerous time to disturb colonies is during late winter and early spring when the bees have been confined for long periods. Infection is spread by moving colonies during the spring because spontaneous infection of bees has become most severe when they are actively cleaning contamination from the combs.

Proof of infection is carried out by microscopical examination to determine the rate of infection.
May I remind you all treatment of any kind will only help the infestation of the bee’s stomach to remain light to ineffectual, but once Nosema is established there is no known cure

There are a couple of methods to try to help the bees by exchange the frames for foundation and feeding syrup to help build the comb, they could be re-queened if the queen was of an age to be replaced.

I hope this has been of some help to disperse the rumours of what can and can’t be used in the treatment of Nosema apis.
Nosema cerana which is now widespread among colonies is more virulent than apis, and again we can only use Fumidil B and or thymol.

Bcrazy,can you please explain why a heavily infected colony treated in spring,and given a comb change, has absolutely no nosema spores the following winter,or indeed at all,where has the nosema gone,not a spore in sight, if it is impossible to ever get rid of.
You say the spores cannot be killed,of course they can,by acetic acid,but obviously not in the bee's.
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It is possible to treat with antibiotics so as to arrest the growth or further infestation.
Treatment in spring and a comb change is good because the infected bees will defecate outside the hive as they will be out flying and not restricted in the hive. Eventually these bees will die off leaving the young colony to build up comb which has not been infected by Nosema spores. Therefore you have a healthy colony.

Normally the infestation will right its self with the bees dying off and no defecation in the hive from adult bees, but if frames are left and not treated (old school) then you will not be rid of the infestation.

Where do bees collect the spores from?

Nosema spores will eventually become inactive if they do not have access to the food inside the bees stomach and can become dormant for a couple of years.
Nosema is a microsporidian which lives of live cells within the stomach of the bee.

> Where do bees collect the spores from?<

Tractor ruts,and other dirty sources of water,where infected bee's have defecated over,or drowned in.I know what nosema is Bcrazy,i've seen enough of it,and got rid of it in the bee's,but it remains in the water sources,as we both know the spores can remain dormant for a very long time.Time for medicated drinking troughs.Did you read this thread on nosema?
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