Nosema

[Tom Bick]

No beejoiful that is for the autumn thymol varroa treatment.

This sticky is the one with the thymol recipe for adding to syrup to help ward of nosema http://www.beekeepingforum.co.uk/showthread.php?t=6513

I am not following all the instructions in that thread as it is for autumn feeding but adding 5ml of the base mix to 1L of 1:1 syrup and then lightly spraying them with three applications and four days between each spray.

I see the autumn feeding as a preventative thing and this treatment is do it or the bees are doomed.

 

[BeeJayBee]

Thanks - that makes it clearer.

I hope I don't have to use it, but I suppose it's best to be prepared in case.

 

[Tom Bick]

Always good to have the tools in the bag when needed and what this forum is all about.

 

[Tom Bick]

Just an update I applied the 3rd treatment today, well 4th if you count the first weaker syrup solution and will take a sample of bees for testing this weekend.

I have to say the bees are completely different and as hivemaker predicted noticeable after the first application moving and flying with a purpose very happy bees.

It will be interesting to see the results. I don’t think they will be completely clear and hope to see that in a few more weeks time but then I don’t know what to expect, but to look at them now you would say they are fit and healthy. Also I will replace the supers this weekend as the 20+ lime trees in sight of the hives are starting to flower and all they need is hot ???? humid weather ????. If only they could move Wimbledon to another time of year.


Just to add another hive in the same apiary has tested positive but only low level compared to the two others and I will watch this hive and perhaps treat if needed once the supers are removed.

 

[Tom Bick]

Thought I should update this thread.

I re-tested the bees at the weekend and the reduction of spores looks pretty good to me with what looks like over 50% reduction. To look at the bees now you would not suspect anything is wrong they are vibrant. I have made the decision to replace the supers and monitor them closely.

When I test them again in a couple of weeks I will hope to see a further reduction as the thymol is known to block nosema spores developing into nosema.

The 2nd photo is after the thymol treatment of hive 1

The 2nd photo is also after thymol treatment of hive 2

 

[Ruary]

Thought I should update this thread.

I re-tested the bees at the weekend and the reduction of spores looks pretty good to me with what looks like over 50% reduction. To look at the bees now you would not suspect anything is wrong they are vibrant. I have made the decision to replace the supers and monitor them closely.

When I test them again in a couple of weeks I will hope to see a further reduction as the thymol is known to block nosema spores developing into nosema.

The 2nd photo is after the thymol treatment of hive 1

The 2nd photo is also after thymol treatment of hive 2

Different magnification to the first shots shown in the original post.
Did you use the same amount of water/ bee when doing the second checks?
It is still a seroius infection.

RE an earlier post Randy's quick squash method is a form of sequential testing and he is testing for an infection rate of over 40%.
The method most people use of squashing 30 bees and examining for spores can be seriously biaised by one bee with a very heavy spore load.
The usual standard for the 30bee sample is to use 1ml. water per bee.

 

[itma]

...
RE an earlier post Randy's quick squash method is a form of sequential testing and he is testing for an infection rate of over 40%.
The method most people use of squashing 30 bees and examining for spores can be seriously biaised by one bee with a very heavy spore load.
The usual standard for the 30bee sample is to use 1ml. water per bee.

I think Quick Squash is appropriate here.
Its about showing the extent of infection.
As in: What proportion of bees are infected - rather than - How densely concentrated are the spores in the colony

Taking a group of bees and pulping them, then judging the average 'crowd density' of spores on a microscope slide is fraught with difficulties.
Control of the soup dilution is one thing, counting the spores is another.

Quick Squash has the concept of individual bees being either badly infected or essentially clear, and estimating the prevalence by seeing the proportion that are clearly bad.

As the 'cure' proceeds, you ought to see the proportion of infected bees declining ...

 

[Tom Bick]

The usual standard for the 30bee sample is to use 1ml. water per bee.[/QUOTE

Far from me to question you Ruary and my testing is way short of your standards but is that right?

 

[Ruary]

The usual standard for the 30bee sample is to use 1ml. water per bee.

Far from me to question you Ruary and my testing is way short of your standards but is that right?

Yes the number is correct
Cantwell used 1 ml/bee, and the COLOSS book which is being published in parts for them by IBRA. uses two criteria one examination of bee individual abdomens to get percentage infection but they admit that this is prolonged and troublesome. the other is mashing the sample of bees and using 1 ml water /bee to get a count of average spores/ bee by using a haemocytometer.
Yates states use a few drops of water and then counts the number of spores per field. They admitted that their standard was purely arbitary.
The Illustrated Encyclopedia of Beekeeping by Morse and Hooper used 10 ml water per 30 bees and an eyepiece graticule to make the count.

Really the important thing is to use the same relative quantity of water per bee so that the comparisons show some validity.

Ruary

 

[Tom Bick]

How could of ever doubted you Ruary, I have today been looking it up on the internet and apparently 1 ml per bee is right but I think 1-2 ml per sample I have been shown is just for confirming nosema is in a hive. Or at least I think thats right.

In the two tests the samples were the same and the magnification is not the same but the best I could achieve, we are talking phone over eye piece technology.

Obviously survival of the two colonies is the most important bit. The object of the thread is to hope and show the effectiveness of thymol on bees with nosema. I understand the sampling of a relatively small amount of bees can give misleading results but hope to show a general reduction in the spores and hope to have no spores in time. It would be great not to but I am prepared to resume treatment in a few weeks time after I have removed the supers. The hives are of good size and now show no obvious signs all is not right.

When I next test I will produce one sample with the 1ml of water per bee and one the same as the previous two samples to compare.

Thanks for the advice every bit helps cheers.

 

[itma]

It'd be interesting to see whether the Quick Squash method showed your reduction.
It only needs a 10 bee sample.
If it is 'expensive' on anything it is microscope cover slips ... but clear plastic has been suggested as a serious alternative. Trimmed to make smaller covers, that allows 5 bees per slide.

Worth a side-by-side comparison?


http://scientificbeekeeping.com/sick-bees-part-16-the-quick-squash-method/

Since the discovery of Nosema ceranae, I and many other beekeepers and researchers have been frustrated by the tedium and apparent futility of counting nosema spores, since many of us haven’t seen any meaningful relationship between spore counts and colony health or production. I strongly suspect that the issue is not that N. ceranae does not cause problems, but rather that our methodology for assessing the degree of infection has been flawed.
...
Unfortunately, as noted by Meana (2010), “the spore count is not directly related to the parasite burden and health status of whole colonies naturally infected by N. ceranae under field conditions.”
...
... what we need to do is to shift to the most meaningful way to measure the potential impact of nosema upon colony health—the proportion of infected bees. Of the various terms used to describe this measure—“proportion of infected bees in a sample,” “percent infected,” or “infection rate”– I prefer the term used by epidemiologists: “prevalence.”

 

[Tom Bick]

I suppose I could do a couple of test samples itma of the quick squash method over a couple of weeks alongside my regular test as a comparison and it will be interesting to perhaps see the variation of infection between the bees.

Its just as well neither of the tests takes that long just a few mins as it now looks like three per hive. One thing I don’t think I will be that interested in counting the spores, to me a visual reduction will do for me.

As for the cover slips you must get 1000’s in a small box and if carful you can clean them that is until you stick one into your finger

 

[Ruary]

It'd be interesting to see whether the Quick Squash method showed your reduction.
It only needs a 10 bee sample.
Worth a side-by-side comparison?

I know Randy talks about a sample of ten bees as did Cantwell but they are both looking for an infection rate (prevalence) of over 40%. For a sample of 10 bees the 95% confidence limit is between 0 and 44%.
So you would not expect to be able to make comparitive measurements with a prevalence of less than that.

 

[drex]

study notes for microscopy recommends a sample of 30 which produces reasonably reliable results, but it is all a bit hit and miss anyway. It would be much more accurate to examine each bee of the sample individually, but that would be so tedious.

Most important is to ensure the sample is of older bees, and to keep your methods consistent.