Apiguard recommendation – The Apiarist

Synopsis : Apiguard task is temperature-dependent however the directions are imprecise at the minimal temperatures wanted for top efficacy. Is Apiguard suitable for the bees to your space? How would possibly you resolve this?

Creation

A couple of months in the past I mentioned the directions provided with some formic or oxalic acid-containing miticides beekeepers use to keep watch over Varroa. The submit was once titled ’Infernal contradictions’ reflecting the state of the documentation offered, both with the bought merchandise or by means of the Veterinary Drugs Directorate (VMD) database of authorized remedies.

Are the directions transparent, unambiguous, significant, correct and useful?

On occasion … however now not at all times 🙁 .

This time I’m turning my consideration to Apiguard, a thymol containing miticide that – used correctly – may be very efficient at decreasing Varroa ranges. It’s an natural remedy and there’s no proof that mites can grow to be proof against the energetic element.

Efficient and no resistance … what’s to not like?

Be affected person … I’ll come to that sooner or later.

I now not use Apiguard (for causes that can grow to be transparent) however did use it, quite effectively, for years once I lived within the Midlands. In surveys of miticide utilization, Apiguard is one among (or continuously the) most generally utilized in the United Kingdom, so this submit must be related for plenty of readers.

This can be a lengthy submit. Apiguard, like different miticides, isn’t ‘have compatibility and overlook’. I you need it to paintings effectively you wish to have to make use of it correctly. This implies you almost certainly want to know the way it really works and do greater than learn the directions .

Excellent and dangerous follow

If you’ll scale back mite ranges the usage of chemical compounds you need to take action in some way that:

• maximises the have an effect on at the mite inhabitants the usage of the minimum efficient dose and/or length of remedy to keep away from harm to the colony
• does now not breach the tips in the case of authorized manner, dose, length or state of the colony when they’re handled

As an example, a unmarried remedy with Api-Bioxal all through a broodless duration within the wintry weather slaughters ~90-95% of mites and is easily tolerated via the bees. The remedy is authorized and is carried out when it’s prone to have most impact on Varroa however minimal have an effect on at the colony.

That is an instance of excellent follow.

By contrast, interleaving each body within the brood field with unbranded fluvalinate strips bought by means of eBay from China in a hive with two rapidly-filling supers is indisputably now not just right follow . The chemical strips would possibly have contained tau-fluvalinate (the energetic element in Apistan) however weren’t authorized via the VMD, the dosage was once some distance too top and any honey can be tainted and undeserving for human intake.

Any directions supplied with accepted remedies, or further documentation and recommendation from the producer/provider, must make the secure and efficient management of the chemical simple i.e. enabling just right follow.

How does Apiguard do on this regard?

Apiguard

The energetic element in Apiguard is thymol, a herbal compound found in thyme and a variety of alternative vegetation. Apiguard is equipped in foil trays containing 50 g of a white gel-like compound. 25% (12.5 g) of that is thymol, the rest is a slow-release provider that guarantees thymol manufacturing happens over a chronic duration of days or perhaps weeks.

The bees want get admission to to the tray of Apiguard for it to paintings so it’s generally positioned at the best bars of the brood frames, with ‘headspace’ offered via an eke. The herbal home tasks task of staff gets rid of the gel, distributing it across the hive.

Thymol seems to be energetic towards Varroa as a vapour and most likely additionally via direct touch. Distribution of the gel across the hive possibly will increase this touch, however – as a result of the sluggish launch components – additionally guarantees that the thymol vapour is maintained at healing (i.e. efficient) concentrations for a protracted duration, thereby killing phoretic mites and the ones launched when new staff emerge.

Thymol does now not penetrate brood cappings, or kill mites in cells, so the efficient vapour focus should be maintained for a minimum of one complete brood cycle.

In follow remedy takes at least one month.

Word Please understand that I’m UK based totally once I talk about allowed utilization strategies and proposals … it may well be other to your nation. The mechanism of motion will in fact be the similar anywhere you might be, so my feedback about temperatures, volumes, periods and so forth must all be legitimate.

Thymol vapour focus

The vapour focus of thymol had to be efficient towards Varroa is it seems that 5-15 micrograms in step with litre (µg/l) of hive air. Those figures are from a Bee Tradition article via Claudio Garrido and I’ve been not able to seek out any printed knowledge in this without delay from the producer, Vita Europe Ltd.

Thymol vapour manufacturing is temperature dependent.

At low temperatures vapour manufacturing is low and it will increase with expanding ambient temperature. On a actually heat day – say above 30°C – hives being handled with Apiguard scent very strongly of thymol. The vapour focus will also be so top that the bees would possibly ‘beard’ on the hive front.

Used correctly, and as reported in numerous assessments of the product, Apiguard can kill 90-95% of the mites in a colony. Vita record trying out it in 10 international locations in Europe, the Center East and North The united states with a median efficacy of 93%.

That’s greater than appropriate and must considerably fortify the well being and therefore overwintering colony survival of our bees.

On the other hand, trying out in northern Italy or two areas of Germany – all spaces with decrease temperatures – was once reported to present 67%, 43% and 72% efficacy, all of which might be too low to successfully keep watch over Varroa ranges within the colony.

So, in abstract Apiguard is:

• a miticide based totally upon a herbal plant product i.e. natural
• simple to manage
• dispensed across the hive via staff all through hive cleansing task
• dependent upon the ambient temperature to reach a sufficiently top vapour focus to kill mites
• widely examined (although predominantly in heat international locations)

Directions to be used

Those are lifted from the forms offered at the VMD database, in particular the present QRD ‘labelling and package deal leaflet’ documentation (revised March 2020). I’ll handiest point out the important thing issues which are related to the remainder of the submit.

• don’t use all through a honey float
• two programs of fifty g of gel in step with colony at a 2 week period
• after the primary fortnight take away the primary tray and change with a recent tray, depart till the tray is empty
• most of 2 remedies in step with 12 months
• use in past due summer time after the honey harvest (when brood provide is diminishing)
• is also utilized in springtime when temperatures are above 15°C
• don’t use the product when the utmost day-to-day temperature anticipated all through the remedy is less than 15°C or when the colony task may be very low or when temperature is above 40°C

A seek of the Vita Europe Ltd. web site turns up some more information on Apiguard together with a lot of scientific-looking research on utility and efficacy, all equipped as PDFs . ’Medical-looking’ as it’s now not transparent whether or not the entire research had been peer reviewed and printed. In fact, this doesn’t imply they’re mistaken or now not price studying. If they’re printed it will had been helpful to offer suitable hyperlinks.

Importantly, since those paperwork are dispensed via Vita Europe Ltd. I believe their contents are proper and authorized via Vita … which turns into related after we believe temperature.

Which we’ll do now 😉 .

Temperature

Temperature is important as it determines whether or not the thymol reaches a healing vapour focus. If the temperature is simply too low the vapour focus will probably be too low to kill the mites.

In relation to minimal environmental temperature the directions merely state:

• is also utilized in springtime when temperatures are above 15°C
• don’t use the product when the utmost day-to-day temperature anticipated all through the remedy is less than 15°C

Which, to be truthful, isn’t vastly useful.

The day-to-day temperatures remaining vulnerable peaked at simply over 15°C however the moderate temperature was once appreciably decrease.

Are the ones suitable prerequisites?

With special occasion/evening permutations the day-to-day most would possibly achieve 15°C however the colony is also semi-comatose more often than not, so decreasing Apiguard distribution.

The Bee Tradition article I discussed previous mentioned that, in assessments carried out in Switzerland, a vapour focus of handiest 4 µg/l was once completed and this was once beneath the healing focus, that means that fewer mites had been killed. Sadly, there was once no quotation I may in finding for the supply of this knowledge.

Why does this subject?

As a result of I stay bees in a temperate northern hemisphere nation and past due summer time/early autumn day-to-day most temperatures are continuously across the 15°C discussed within the Apiguard directions.

If the miticide does now not achieve the healing focus it is going to now not be efficient … it does now not subject in the event you depart the remedy on for longer, many mites will live to tell the tale.

It’s successfully the similar as the usage of antibiotics at too low a dose …

Learn the FAQ …

Helpfully, Vita Europe additionally produce an Apiguard FAQ (PDF).

It’s price noting that the FAQ has clearly been written as a generic report, acceptable anywhere Apiguard is offered. It incorporates references to formulations now not to be had in the United Kingdom and makes a lot of statements that doubtlessly or if truth be told war with the Apiguard directions supplied with the product in the United Kingdom.

As an example, it states that the dose is ’50 g in step with ten brood frames’.

Maximum UK brood packing containers have 11 frames … however does it subject whether or not the frames are Nationwide, 14×12 or Langstroths? The ones packing containers all have considerably other volumes which is able to have an effect on the energetic focus of thymol completed .

It additionally contains connection with supers …

It’s preferable to take away supers prior to treating with Apiguard. Apiguard would possibly taint honey in supers, however it’s not likely, particularly if the honey retail outlets are sealed

To me, this means that capped honey retail outlets can be usable. They even upload ‘Honey accumulated all through Apiguard remedy will also be fed again to the bees’.

There’s no point out of human intake.

Does this contradict the United Kingdom rules? Those state that Apiguard must now not be used all through a honey float. Does that imply that capped honey already provide when treating all through a dearth may well be offered?

All just a little complicated, however I’m digressing … what about temperature?

There are two related feedback within the FAQ:

The exterior temperature must be above roughly 15°C (60°F), which means that that the colony is energetic.

… and …

Apiguard can paintings at low temperatures however is most efficient when temperatures have a day-to-day minimal of 15°C

Hmmm … I need it to be efficient … ‘can paintings’ sounds just a little underwhelming.

… and the paperwork equipped via the producer

I then learn all of the extra paperwork referenced as ‘additional knowledge’ at the Vita web site. A couple of make indirect references to temperature, however just a couple have particular recommendation:

The primary, while now not referencing a particular temperature, is attention-grabbing:

The temperatures recorded within the colony counsel that the common day-to-day temperature must be thought to be a proscribing issue on using evaporating merchandise. Certainly, on the level of utility of the thymol, the temperatures rely now not handiest on the ones out of doors the colony, but additionally at the thermoregulating actions of the bees at the brood combs, sun irradiation and the fabrics used to build the hive (from this PDF).

However the second one connection with temperature may now not be clearer:

The producer recommends use of the product when the imply day-to-day temperature varies between at least 15°C and a most of 40°C (from this PDF).

Now we’re getting someplace!

It was once the latter report (from Apimondia 2007), in conjunction with research of native temperatures, that persuaded me that Apiguard was once now not a suitable miticide to be used in my a part of Scotland.

Is it suitable the place you are living?

Temperature, colony task, thymol vapour and quantity

The place Apiguard is anxious the temperature influences two issues; the era of the thymol vapour and the task of the colony which distributes the thymol-containing gel across the hive.

If the temperature is simply too low the colony will probably be clustered and/or inactive and the vapour focus won’t ever get top sufficient to be efficient towards mites.

Now not just right.

Conversely, in heat climate when the midnight temperature stays sufficiently top, the colony will probably be energetic within the hive always and the thymol vapour focus will probably be top.

Be long gone, pesky mites!

Possibly, if the temperature fluctuates – from chilly nights to heat days – the colony will handiest be correctly energetic all through the hotter day however the vapour focus will not be top sufficient all through the cooler nights to be efficient.

If I sound unclear at the latter level it’s as a result of I’m.

Inside of the clustered bees at evening the temperature must stay top sufficient to lend a hand the thymol grow to be a vapour however the warmed a part of the hive could have a smaller quantity. Since the hive air quantity – which is what’s circulating when the bees (and mites) respire – is the whole quantity of the brood field the general vapour focus will probably be decrease.

Will it’s too low to be efficient?

I don’t know.

Quantity crunching

In my deliberations about the usage of Apiguard in Scotland I used 15°C as a threshold temperature to lend a hand in my choice making. Within the absence of any company temperature information and thymol vapour focus it was once all I may paintings with.

The entire graphs are for my Fife apiaries, however the similar knowledge may be generated for any place within the nation if in case you have get admission to to native climate knowledge (and I mentioned remaining week easy methods to get admission to that).

Highs, lows and averages

Most often, the temperature all through a 24 hour duration fluctuates. Nights are in most cases less warm than days. The temperature on successive days or nights additionally varies.

In the event you plot the utmost (purple strains) and minimal (blue strains) temperature you get fairly ‘noisy’ graphs (the skinny strains) which will also be smoothed via averaging the temperature over an extended duration, as an example 7 days (the thick strains).

In Fife, a 7 day sliding (i.e. days 1-7, 2-8, 3-9 and so forth.) moderate most day-to-day temperature exceeds 15°C for lots of the duration Might to mid-October. On the other hand the 7 day sliding minimal temperature virtually by no means exceeds 15°C … no less than for 2019 which is the 12 months plotted within the graph above.

In the event you wanted a minimal temperature of 15°C for Apiguard to paintings you’ve were given an issue … no less than in Fife .

Possibly extra helpful is the imply day-to-day temperature. That is plotted in inexperienced above. If Apiguard wishes an average temperature of 15°C to paintings successfully then that is exceeded – in 2019 – from mid-June till past due August.

The imply temperature isn’t calculated via including the utmost and minimal temperature in combination and dividing via two. As an alternative it’s decided from the common (each 1-5 mins most often) temperature readings over all of the 24 hour duration.

On the other hand, some private climate stations handiest record day-to-day highs and lows.

You’ll be able to calculate an approximate imply day-to-day temperature from those (Hello+Lo/2; purple line above) however it is going to be an overestimate of the particular imply (blue line above), via ~0.5-0.9°C (in my revel in).

Autumn remedy with Apiguard

Apiguard remedy is added as quickly because the summer time honey is taken off the hive. Most often for me that is both the second one or 3rd week of August.

The remedy duration is a minimal of four weeks and – in line with the FAQ – optimally 6 weeks. All through this era the temperature must be top sufficient (no matter this is) to reach a thymol vapour focus this is efficient in killing mites.

When doing this kind of research you can’t simply take a look at information from 365 days as it could had been unseasonably chilly or heat.

Listed below are the 7 day sliding imply day-to-day temperatures for 2018-2020 and 2022 .

Past due August and past due September had been appreciably hotter in 2019 (the blue line). On the other hand, all the ones strains are nonetheless just a little of a large number, but when you’re taking a median throughout a number of years you get a graph (beneath) this is a lot more uncomplicated to interpret.

In my a part of Scotland the imply day-to-day temperature is in most cases beneath 15°C from the remaining week in August i.e. the whole time I might expect to make use of Apiguard if that was once my selected miticide remedy 🙁 .

I’ve shaded the world beneath 15°C to suggest that mite killing turns into increasingly more useless the additional the imply day-to-day temperature is beneath this temperature.

Sadly, I don’t know the actual (imply day-to-day temperature) threshold and Vita Europe Ltd. don’t supply this knowledge of their directions, FAQ or related documentation 🙁 .

Choices, selections

If you wish to use Apiguard you almost certainly want to do a identical type of research. In the event you don’t suppose my interpretation of the Vita Europe documentation is proper then learn the forms and observe your individual threshold.

I finished the usage of Apiguard once I moved from the Midlands to Scotland.

My overwintering colony losses within the Midlands had been a little bit upper than they’ve ever been in Scotland. I’ve at all times assumed that this was once as a result of Scotland ‘advantages’ from less warm winters. Because of this there may be virtually at all times a broodless duration between past due October and mid/past due December (in most cases previous fairly than later). This makes a ‘midwinter’ (however it isn’t) oxalic acid remedy very efficient in killing off any mites that escaped the fall remedy, or that experience reproduced since then.

On the other hand, out of hobby I retrospectively graphed (above) the imply day-to-day autumn temperatures (August to October) for my Midlands apiary for 5 years (2018-2022; skinny strains at the graph above) and the common of those years (thick inexperienced line).

The person years plotted make for a loud graph, however it’s quite transparent that an ordinary 4-6 week Apiguard remedy window spanning from the remaining week in August till early October is prone to come with an important duration (possibly 50% of the time) when the imply day-to-day temperature is beneath 15°C.

What would the results of this be?

Mites from capped cells which are launched later all through the remedy window would possibly effectively now not revel in deadly thymol vapour concentrations. They’ll subsequently break out remedy and can be capable of move on to breed.

Possibly my upper wintry weather losses had been because of useless Apiguard keep watch over of mite numbers … ?

Different issues

I’ve concentrated at the affect of temperature as a result of it’s vital for efficient thymol keep watch over of mites and since it’s poorly defined within the Apiguard directions.

On the other hand, it’s now not the one factor to take into accounts …

Queens

Top thymol concentrations can forestall queens from laying.

About 50% of my colonies would revel in an enforced brood damage all through Apiguard remedy . Since colonies must be rearing wintry weather bees and colony energy is a number one determinant of overwintering survival, the rest that forestalls the queen from laying isn’t splendid.

At the plus aspect I don’t ever keep in mind shedding a queen all through Apiguard remedy.

’Headspace’

There’s a report at the Vita web site that demonstrates that further area across the Apiguard trays at the best bars will increase the efficacy of remedy. 3 other intensity ekes had been used – 6.5, 28.5 and 66.5 mm – and ended in 78%, 87% and 92% of mites within the colonies to be killed.

So … extra is healthier?

They conclude that the enhanced air movement aids distribution of the thymol vapour, so making remedy more practical. The private eke would have higher the amount of the hive via ~12 litres (i.e. ~25% in relation to a Nationwide brood field).

While those effects are attention-grabbing it’s essential to notice that those experiments had been carried out in Italy when the imply day-to-day temperatures had been 20-25°C.

In cooler climates I’m now not sure that the similar (or any?) growth of remedy can be observed.

At decrease temperatures the vapour focus of thymol completed will probably be decrease anyway. If the amount of the hive is then higher via the usage of a deep eke it’ll scale back the vapour focus but additional, beneath a therapeutically efficient degree.

The FAQ recommends the usage of an empty tremendous … is that this nonetheless beneficial if the temperatures are low?

Apiguard recommendation

Apiguard works effectively whether it is used correctly, which incorporates suitable native prerequisites. If you wish to use Apiguard then I might counsel:

• test the native ancient imply day-to-day temperature for 4-6 weeks after your selected remedy date. If a far of this era may be beneath 15°C then remedy will probably be much less efficient. Certainly, it will not be efficient sufficient to forestall mite and virus harm in your colonies.
• in case your interpretation of the Vita-provided knowledge is that 15°C isn’t a suitable threshold then make a selection a greater one whilst you do the research.
• upload the Apiguard trays to the highest bars surrounded via a shallow eke with a well-insulated crownboard to lend a hand spice up the in-hive temperature.
• shut the open mesh flooring to retain the thymol vapour inside the hive until the elements may be very heat. In the event you’re handiest reaching a low vapour focus of thymol you need to stay up to imaginable within the hive. Thymol vapour is denser than air.
• feed your colonies concurrently you deal with with Apiguard.
• track day-to-day imply temperatures all through remedy … whether it is appreciably beneath 15°C believe the will for an extra temperature-independent miticide.
• apply the present directions supplied with the product and skim the extra knowledge offered via Vita Europe Ltd.
• keep in mind to stay a report of batch/lot numbers.

That would possibly appear to be a large number of paintings.

On the other hand, in the event you’re going to make use of a miticide it’s essential you utilize it successfully.

If it doesn’t paintings you’re simply losing cash and unnecessarily exposing bees to chemical compounds.

And, in spite of everything, there’s no precise beekeeping to be finished at the moment of the 12 months 😉 .

Have a laugh

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