Fondant, mushrooms and DWV – The Apiarist

Synopsis: Two contemporary research on doable remedies for DWV and a dialogue of the practicalities of feeding fondant … and improving the leftovers.

Creation

That is the 47^th put up of 2023 and I’ll quickly be writing the pre-Christmas seasonal evaluations, the advisable listing of items for beekeepers and the yearly “Should you’ve now not but handled with oxalic acid then you definately’ve left it too overdue” reprimand. However there’s nonetheless every week or so till the final of the ones is wanted, so I’ll talk about one thing else lately

It’s all the time somewhat difficult to understand what to jot down about at this degree of the season. Some hardcore science will go away the ones in search of well timed sensible beekeeping guidelines in need of. Conversely, the ones of you who’ve already completed your iciness oxalic acid remedy in your broodless colonies don’t want any sensible guidelines as you’re now unfastened to take into consideration different issues till early March.

So, within the hope of enjoyable ‘the entire folks one of the time’ , I’m going to combine’n’fit some very contemporary science with a few feedback about overdue season colony control. And, if that wasn’t sufficient, I’ve thrown in an overly transient paragraph on the finish of a few long run adjustments that shall be going down right here.

Feeding fondant

I simplest feed fondant when making ready colonies for iciness. Maximum of my colonies this season gained both 6 kg (for the reason that brood field was once closely backfilled with retail outlets already) or a complete 12.5 kg block. They’re not going to want extra ahead of Spring, and a few didn’t even set up to complete the block I did give them (extra on that later).

Fondant is indisputably costlier than feeding syrup. I’ve by no means labored out how a lot costlier as a result of I don’t in point of fact care … the advantages to me some distance outweigh the price differential.

• I’ve no want to acquire and retailer syrup feeders, be they 15 kg buckets with perforated lids, washing up bowls full of straw, or a £72 Ashforth feeder. Yikes!
• I don’t want to stand over the range blending gallons of thick (2:1 through weight) syrup, or stay barrels to hold and distribute it … which additionally manner I don’t spill it within the apiary and inspire robbing (or, worse, the kitchen and all of the grief that would entail).
• Fondant is ready-wrapped, solid and can also be saved for years. It’s all the time waiting to make use of. I’ve were given a few hundred kilograms tucked away ‘simply in case’ within the shed.
• Colonies take fondant down extra slowly. I assume this is helping the queen lay eggs for longer because the brood nest isn’t backfilled with syrup being ripened. Rather than reputedly not unusual sense, I’ve were given no actual evidence for this and will have to possibly officially take a look at the idea .
• The empty bins can accommodate 16 340 g jars and are helpful for distributing honey in.
• There’s extra, however that’s sufficient to be happening with.

Leftovers

Maximum colonies end their fondant, even though this is determined by the supply of overdue season nectar. Bees proceed to forage and in the future they run out of area, so some fondant might stay.

My east coast bees have a tendency to complete the entirety, simply leaving an empty ‘husk’ – the blue bag – caught all the way down to the queen excluder with a little of propolis and brace comb. At the west coast the bees are very frugal, it’s a little hotter they usually ceaselessly don’t even end a part block of fondant. The brood field is ceaselessly heavy with late-season heather retail outlets.

Dangle on … queen excluder?

If you want get right of entry to to the brood field – as an example, so as to add, reposition or take away Apivar strips – it’s very tough if there’s a large block of fondant caught down onto the highest bars of the frames. As an alternative, it’s some distance more straightforward to make use of a framed stressed out queen excluder (QE) to toughen the fondant simply above the highest bars. The QE can simply be lifted, along side the fondant, and simply as simply changed … with out crushing a technology of bees.

Alternatively, as the chillier climate approaches I really like to take away any ultimate fondant ahead of the bees cluster tightly for the iciness.

Why take away it?

I used to be requested this just lately after speaking to the great people at Perth and District BKA. There are 3 causes:

1. The hives are stuffed with retail outlets. My bees are frugal. It’s not going they’ll end their retail outlets. In reality, it’s now not extraordinary for me to take away a body of sealed retail outlets from the out of doors of the field in early spring (which I set aside for making up nucs in June) to offer the colony area to make bigger. Since they almost certainly don’t want the fondant there turns out little level in leaving it – and a few causes (see beneath) to not.
2. Fondant below the crownboard will act as a heatsink and soak up one of the heat generated through the colony. In fact, if the roof is satisfactorily nicely insulated this shouldn’t be a subject, however the fondant, the distance round it and any further gaps created through the eke used to house it will all be higher in the event that they weren’t there.
3. Extra considerably, fondant deliquesces . Until the bees are continuously nibbling away on the decrease face of the block it should get sufficiently gloopy to drip down between the brood frames. The one time this is a matter is that if the colony is small (or will get small all the way through the iciness) and/or the cluster strikes clear of the fondant overhead. Once more, higher have shyed away from within the first position.

I heft the colonies periodically within the iciness so, if they’re too gentle, I will be able to upload fondant again as wanted.

Eliminating the fondant

It’s mid/overdue November, 7°C and spitting with rain.

The fastest strategy to get well the surplus fondant is to take away the roof and crownboard, prise up the QE and fondant block, shake off the bees (then shake off but extra bees) after which reassemble the hive.

Alternatively, even then there is also extra bees lethargically wandering across the sticky face of the fondant block, all of a sudden getting chilled. Do you sacrifice those or go away the block out hoping that the bees will fly again … which, at 7°C is almost certainly the similar factor.

It’s more straightforward – even though takes two visits – to take away the roof then gently prise up the QE, fondant and crownboard ahead of straight away returning them to the hive over a clearer board. The bees make their very own as far back as the cluster, benefitting from the heat of the colony. The next day take away the clearer, QE and fondant and change the crownboard and roof.

I did this on part a dozen hives final week; slightly a bee flew on both talk over with and the bottom of the fondant was once totally transparent of bees after elimination. The colony was once nearly undisturbed and there have been no casualties.

I retailer the recovered unused fondant in a tightly sealed plastic bag. Don’t go away it exposed as it is going to soak up water. If wanted later within the iciness I’ll both use it ‘as is’, or upload 1-2 kg blocks to plastic trays (in most cases from grocery store packaging of meat or mushrooms) for underweight colonies. Then again, I dissolve it in scorching water (60% through weight) to make skinny syrup for stimulative early season feeding.

Magic mushrooms

And, since I’ve discussed mushrooms …

A fascinating paper has just lately been revealed in The Magazine of Insect Body structure on mushroom (Cortinarius caperatus) extracts and DWV an infection (Svobodová et al., 2023). The creation ends with the next sentence:

Our effects demonstrated that the alcohol extract of C. caperatus can be utilized as a protected and efficient remedy to cut back DWV an infection.

Hmmm … possibly.

Mushroom extracts (and, extra particularly, their secondary metabolites) have lengthy been identified to have antiviral results. Some prevent viruses infecting cells whilst others save you the viruses from replicating as soon as they’ve inflamed cells (two various things altogether, even though now not all research seem to know this). Generally the mechanism of motion stays a thriller.

Svobodová and co-workers display that an alcohol extract – or just a powdered preparation – of the fit to be eaten gypsy mushroom Cortinarius caperatus gave the impression to inhibit the degrees of deformed wing virus (DWV) in caged honey bees.

Great.

Dangle on … the identify of the paper states ‘inhibits the advance [of] an infection’ of DWV. The bees are already inflamed and there’s no proof that the mushroom extract stops them getting inflamed. Bees fed mushrooms have decrease quantities of virus, so possibly it inhibits the replication of the virus that’s already provide?

Pedantry possibly … that’s my prerogative.

How nice is the inhibition?

It sounds as if beautiful excellent.

Bees fed mushroom extracts have virus ranges which might be about 1/1000^th of the keep an eye on bees.

However …

You knew there needed to be a however.

The absolute ranges of virus don’t seem to be proven within the paper. Let’s supply some context. A bee uncovered to Varroa all the way through building would possibly comprise as much as 10¹² copies of the virus. That’s a million,000,000 or a trillion. Some mite-parasitised bees have decrease virus ranges, possibly 100-1,000 instances much less, however it’s nonetheless an overly huge selection of viruses.

Bees now not uncovered to Varroa all the way through building (in a hive by which mite ranges are nicely managed) might comprise simplest 10⁴ or 10⁵ copies of the virus. A biggish quantity (10,000 to 100,000), however ten million instances smaller than 1000000000000.

Subsequently, significant discounts of virus ranges are measured in thousands and thousands, now not hundreds. A minimum of significant on the subject of bee or colony well being.

How do colonies (somewhat than caged bees) reply when fed extracts of mushrooms?

No longer specifically convincingly. The graph within the paper (A, above) presentations a 10-fold relief in relative virus ranges which is statistically important, however now not precisely overwhelming. Apparently, one outlier pattern (the gray triangle) was once left out from the calculations for some reason why and I think this knowledge would now not were statistically important had it been integrated.

There’s extra within the paper (no mushroom residues in honey, no obvious unfavourable have an effect on on employee bee longevity, gene expression research and many others.) and it’s surely a subject that merits extra paintings.

However, it’s an overly good distance from being a ‘protected and efficient remedy to cut back DWV an infection.’

So, magic mushrooms … however now not magic bullets.

Mushroom extracts (one thing I’ve written about up to now) are almost certainly now not (but?) a quick-fix to the Varroa-DWV drawback.

dsRNA

And, as some other contemporary paper (Smeele et al., 2023) suggests, neither is double stranded RNA (dsRNA).

Just like the mushrooms, I’ve mentioned dsRNA a few instances ahead of. This is a strategy to induce an RNAi (interfering RNA) reaction. You will have to recall to mind this because the immune gadget of bees (or, extra typically, bugs); like our personal immune gadget it ‘learns’ from pathogen publicity, and it may be ‘primed’ through prior vaccination to supply next coverage. Not like our immune gadget it’s based totally upon nucleic acids, somewhat than proteins.

I’m now not going to enter the gory main points of this paper as the consequences are unfavourable i.e. what they tried to do (vaccinate bees towards DWV) didn’t paintings. This was once each disappointing and somewhat unexpected as earlier research have proven a discount in DWV ranges through prior feeding of bees with syrup comprises dsRNA that goals DWV.

Alternatively, this find out about was once completed somewhat otherwise, and in a way that a lot more intently recapitulates how growing pupae are uncovered to DWV. As such it’s specifically fascinating, and means that dsRNA ‘remedies’ won’t be offering as a lot promise as to begin with idea.

Experimental mini-nucs have been maintained, fed with syrup containing dsRNA towards DWV (or keep an eye on dsRNA) and Varroa have been added. Growing larvae have been fed through staff, the cells have been capped (without or with prior Varroa infestation) and the employees that due to this fact emerged have been tested for deformed wings, virus ranges and proof of Varroa parasitisation.

Even if Varroa parasitised bees had very a lot upper virus ranges, prior feeding with DWV-specific dsRNA didn’t scale back the percentage of bees with wing deformities or the degrees of DWV in those bees.

Why the variation with earlier research?

On this experiment the purchase of DWV was once by the use of two routes; whilst being fed through the nurse bees within the mini-nucs, and – for the unfortunates uncovered to mites – whilst being fed on through the parasitising Varroa throughout the capped mobile.

It’s the inclusion of the latter transmission course that in point of fact units this find out about aside, and what makes it a extra reasonable take a look at to resolve whether or not a possible treatment is valuable.

The hope/expectation was once that the growing pupae would have received dsRNA from the nurse bees, an antiviral immune reaction would were stimulated within the pupae and they might have subsequently had decrease DWV ranges (and less signs) after publicity to Varroa. 

Smeele and co-workers provide an explanation for their failure to reveal this through variations within the nucleic acid collection of the dsRNA and the viruses received from Varroa.

Successfully the vaccine and the virus have been imperfectly ‘matched’.

While surely an opportunity there is also an alternate rationalization to do with the localisation of the immune reaction which wasn’t mentioned. Most likely Varroa-acquired DWV bypasses this immune reaction when the mite feeds upon the haemolymph or fats frame of the growing pupa?

DWV is a variable virus. Right through replication it makes mistakes that are integrated into the virus genome. Some are unfavourable (those are misplaced for the reason that virus is uncompetitive or non-viable), others are really useful and decided on for. The remaining are impartial … however those nonetheless imply that the virus varies and so might give a contribution to flee from the immune reaction (whether or not herbal or brought about through dsRNA).

Any efficient DWV treatment will have to consider this herbal variation within the DWV inhabitants, and the consequences offered through Smeele et al., (2023) recommend that this can be some distance from simple.

The way forward for The Apiarist

The Apiarist is ten years outdated subsequent month. The web site ‘design’ (and I exploit that time period within the loosest conceivable sense) is getting unwieldy, tough to learn and – more and more – very time eating to take care of. Early subsequent 12 months there shall be a big overhaul of items. Some ‘options’ will disappear altogether, confidently along side one of the flaws.

Inevitably some issues gets damaged … it’ll worsen ahead of it will get higher.

I’ll supply some more information ahead of I press CTRL-ALT-DEL.

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References

Smeele, Z.E., Baty, J.W., and Lester, P.J. (2023) Results of Deformed Wing Virus-Concentrated on dsRNA on Viral Lots in Bees Parasitised and Non-Parasitised through Varroa destructor. Viruses 15: 2259 https://www.mdpi.com/1999-4915/15/11/2259.

Svobodová, Ok., Krištůfek, V., Kubásek, J., and Bruce Krejčí, A. (2023) Alcohol extract of the gypsy mushroom Cortinarius caperatus inhibits the advance of Deformed wing virus an infection in western honey bee (Apis mellifera). Magazine of Insect Body structure 104583 https://www.sciencedirect.com/science/article/pii/S0022191023001099.