Larger queens, higher queens – phase 1

Synopsis: Contemporary analysis at the maternal impact in honey bees suggests queen rearing the use of employee larvae would possibly produce undersized and underperforming queens.

Advent

Nearly all of books and articles I’ve learn on queen rearing emphasise that larger queens are higher queens. The explanation is unassuming. Larger queens are higher as a result of their higher abdomens include extra ovarioles and bigger spermatheca. With out getting too anatomically technical, those are the reproductive organs for generating eggs and storing sperm. Huge queens will have to due to this fact be capable to lay extra eggs for longer; better fecundity, as scientists name it.

Extra eggs – all different issues being equivalent – imply higher, more potent, colonies, which means that extra honey … or extra nucs, or propolis or pollination or no matter you stay bees for.

There may be just right strengthen – each anecdotal and medical – for some great benefits of higher queens, courting again many years .

On account of this, directions on queen rearing normally tension the significance of feeding your mobile elevating colonies properly, even supplementing them with syrup and pollen if wanted. This advantages larval building, so expanding the dimensions of the ensuing queen.

Alternatively, very fresh research counsel that the foundation of the beginning subject matter – the larva – used for mobile elevating has a basic affect at the completed queen.

Those research display, for the primary time, a maternal impact in honey bees.

The effects suggest that the strategies used to rear virtually all queens (via ads and amateurs) will lead to undersized, poorer high quality, queens than may be accomplished.

After all, I feel there are implications from those research that may inspire extra inexperienced persons to start out queen rearing.

That is the primary of a 3 phase sequence on queen rearing. Portions two and 3 will stick with in the end (even though most likely now not straight away).

These days I’ll quilt the science. Someday, I’ll speak about the sensible beekeeping … keep tuned.

‘Standard’ strategies used to rear queens

After all, beginning any description of a beekeeping manner with the phrase standard manner I’ll be swamped via a tsunami of feedback like “I’ve by no means carried out it that means”.

Endure with me, this bit simply units the scene …

I outline ‘energetic’ queen rearing as any manner that doesn’t depend at the herbal manufacturing of swarm cells.

In those ‘energetic’ strategies, a colony is made receptive to generating new queens, for instance via eliminating the unique queen. Underneath the ‘emergency reaction’ this induces, the colony begins to rear new queens if they have got – or are supplied with – appropriate beginning subject matter.

Through desire, a colony rears new queens from 3 day previous eggs, however they are able to additionally use very younger larvae.

Beekeepers exploit this reaction via introducing decided on younger larvae (from a ‘just right’ colony), steadily introduced vertically in wax or plastic cups.

Those larvae are fed copious quantities of royal jelly, broaden impulsively and emerge as virgin queens.

I’m hoping that’s a generic sufficient description that the majority readers each recognise and will settle for.

Prior to transferring on, I need to tension one crucial level … when queen rearing the use of the emergency reaction, the larvae decided on to be reared as new queens are employee larvae.

For business or many beginner queen rearing approaches, those younger employee larvae are grafted from a donor colony.

Grafting comes to the guide switch of a tender larva from a employee mobile to a vertically-orientated mobile within the mobile elevating colony. This vertical orientation triggers the copious feeding with royal jelly, and this wealthy nutrition induces the adjustments in methylation and gene expression that convert what would have evolved right into a employee bee into a brand new queen.

Masses of hundreds of queens are produced like this yearly.

Maternal results

A maternal impact is the causal affect of the mummy at the phenotype of the offspring.

The phenotype is the illusion or efficiency of a person. The OED defines it as:

The sum overall of the observable traits of a person.

Clearly, there’s a genetic courting between the queen and the egg she lays. Alternatively, this isn’t a maternal impact.

The latter is extra in particular taken to imply a better funding via the mummy (queen with regards to honey bees) in sure younger which might be being reared.

As an example:

• in some geese and fish, the feminine makes a better funding in egg manufacturing (i.e. laying higher eggs) if the perceived high quality of the mate is upper
• the ant Pheidole pallidula produces higher eggs right through the a part of the season through which sexual generations are produced

In those well-documented examples, the mummy produces higher ‘high quality’ eggs best below sure instances. This may increasingly build up the long-term possibilities for the survival of the progeny.

Till a couple of years in the past, there have been virtually no research of the maternal impact in honey bees. Queen building was once thought to be to be solely because of the environmental stipulations skilled via the larva. That is exploited once we rear queens from grafted employee larvae.

Alternatively, between 2019 and 2023 3 comparable research have been revealed demonstrating that queens lay higher eggs destined to grow to be queens, and that the ensuing new queens are higher and extra productive.

I’m principally going to concentrate on research via Wei et al., (2019) and Yu et al., (2023) as those include effects which might be more straightforward to explain and maximum out there with out the will for a doctorate in molecular genetics.

A testable speculation

Like every just right experiments, the preliminary query posed was once rather simple:

Do queens produce higher eggs when laying in queen cells?

Which, after all, straight away activates the most obvious follow-up query …

Do higher eggs generate higher (or higher) queens?

To check this speculation, it was once essential to urge a queen (or a number of, as there are lots of repeats on this learn about) to put eggs in each employee and queen cells, to characterise the eggs laid, after which to rear them into new queens below standardised stipulations.

The variation between queen cells and employee cells is basically dimension . Employee cells are narrower than queen cells.

The authors used a changed device first described within the American Bee Magazine (Pan et al., 2013). That is widely very similar to the Nicot Cupkit device acquainted to many beekeepers.

A sheet of plastic basis was once engineered to include detachable mobile cups on brief spigots. The cups have been both small or huge diameter – representing employee or queen cells. The quick spigot aided dealing with the egg-containing mobile cup with out touching the egg.

After the queen had laid within the mobile cups they may well be got rid of from the encompassing comb and introduced, vertically, on a mobile bar body in a colony set as much as rear queens.

Employee and queen mobile cups have been 4.9 mm or 9.7 mm in interior diameter respectively. The ABJ article best describes one dimension. You’ll wish to learn it and the strategies segment of Wei et al., (2019) for complete main points.

Take into accout

As is same old … there are many repeats within the learn about. Other queens, other colonies and so on. Effects are both statistically vital, which means very not likely they’re because of likelihood, or now not statistically vital. The latter does now not imply that they’re because of likelihood, however that they may be.

For brevity, I’m going to concentrate on the statistically vital effects and now not come up with all of the gory information about numbers of repeats, same old deviation or the statistics. If the consequences don’t seem to be vital however are attention-grabbing, I’ll make that transparent.

Pour your self a stiff drink (or two) and skim the paper(s) your self; they’re all Open Get right of entry to and freely to be had.

You received’t remorseful about it .

Queens lay higher eggs in queen cells

Eggs exchange in dimension right through building. Due to this fact, the authors standardised each the length of egg laying and the timing of egg sizing. Queens have been caged on frames containing queen mobile cups for six hours after which transferred for an additional 6 hours to a body containing employee mobile cups. The load of eggs was once made up our minds as quickly because the queen was once got rid of, i.e. they have been not more than 6 hours previous.

Eggs laid in queen mobile cups (QE = queen eggs) have been 13.26% heavier, 2.43% longer and four.13% thicker than eggs laid in employee mobile cups (WE = employee eggs).

For the rest of the learn about, Wei et al., (2013) when compared queens reared from those QE or WE. I’ll time period those QE- or WE-queens.

Alternatively, for comparability, they moreover incubated one of the crucial WE within the unique colony till they have been 2 day previous larvae (designated 2L) ahead of shifting them to the queen rearing colony. Those are older than could be used for queen rearing, and could be anticipated to supply substandard queens (I’ll name those 2L-queens) … endure that during thoughts as I speak about the consequences.

Greater eggs produce heavier queens

Queen and employee eggs (QE and WE) and 2L larvae have been reared in the similar queenless mobile elevating colonies, the ensuing queen cells have been caged after capping and the queens that due to this fact emerged have been amassed and weighed.

Within the 5 mobile elevating colonies used (best 3 proven above), QE-queens have been the heaviest, and have been considerably heavier than WE-queens in 3/5 colonies. The variation in weight between the QE- and WE-queens was once ~10%.

2L-queens have been typically the lightest total, even though they weren’t all the time considerably lighter than WE-queens.

Heavier queens have extra ovarioles

Ovarioles are necessary … we’ve identified because the early 70’s that queens with extra ovarioles are extra fecund.

QE-queens had 13% extra ovarioles than 2L-queens, a vital distinction. Alternatively, QE- and WE-queens didn’t have considerably other numbers of ovarioles within the first learn about.

I’ve now not afflicted appearing but every other graph as an example this outcome.

In a contemporary follow-up learn about via the similar authors (Yu et al., 2023) they analysed the reproductive skill of those queens. On this learn about, they additionally re-quantified ovariole quantity and the load of the thorax of the queens.

Why thorax weight? Thorax weight is necessary because it displays the dimensions and energy of the flight muscle mass in addition to being indicative of the entire dimension of the queen. The queen would possibly not fly a lot – a couple of orientation and mating flights, and when swarming – but if she does it will be important that she flies strongly.

Like the load total (see above), the thorax weight of QE-queens was once considerably more than WE- or 2L-queens (that have been additionally considerably other). As well as, on this newer learn about, the ovariole quantity in QE-queens was once considerably more than WE- or 2L-queens when analysed.

Why was once there a distinction within the newer learn about? I don’t know, and the authors don’t remark …

Reproductive high quality of reared queens

You’ll be able to measure reproductive high quality of queens in two basic techniques; the collection of eggs laid and the colony expansion doable, measured relating to capped employee cells.

QE-queens laid considerably extra eggs than 2L-queens, however the different comparisons (QE vs. WE or WE vs. 2L) weren’t considerably other. For hobby, I dug into the numbers and appeared on the queen laying charges that have been ~250-450 in 6 hours, so ~55 in line with hour or ~1 in line with minute … always. What a lifestyles!

At 12 days the authors measured capped employee cells the place the consequences have been equivalent in score and importance to the egg laying effects i.e. QE >> 2L, however no vital distinction between the opposite two comparisons. Alternatively, at this level the score was once a little extra evident … QE > WE >2L, with reasonable numbers of capped cells at 12 days being ~6,500, ~5,500 and ~4,000 respectively

The general distinction they quantified within the reproductive capability of reared queens was once somewhat ordinary (a minimum of, it appeared that solution to me). Eggs laid via QE-queens have been considerably longer than the ones laid via WE- or 2L-queens, however have been a equivalent weight and thickness.

I’m now not certain what this implies.

A snappy abstract …

Even if there’s a little bit of variation, the take house message up to now is that queens reared from eggs laid in queen cells (QE-queens) have been:

• heavier, with a bigger thorax
• had extra ovarioles
• laid extra eggs, and
• produced extra brood

The ones are all options you can almost certainly need to see to your queens.

How do progeny queens or employees reared from QE-queens carry out? Are they higher than progeny from WE- and 2L-queens?

Arguably, that is much more necessary than fecundity in line with se.

Dimension and productive capability of employee progeny

The dimension of employees that evolved from eggs laid via the 3 queen sorts was once made up our minds. Employee progeny from QE-queens have been considerably heavier than from WE- or 2L-queens, and so they had longer and wider wings.

Productive capability is a time period that covers a variety of employee task; water, nectar or pollen assortment, honey saved, larvae fed, corpses got rid of, cells wiped clean and so on.

Almost about the perfect of those to quantify is pollen assortment. You rear brood from QE-, WE- or 2L-queens, label a number of hundred newly-emerged employees after which – as soon as they have got matured into foragers – you seize returning marked pollen-carrying bees and weigh the contents in their pollen baskets .

Staff from QE-queens amassed extra pollen than employees from 2L-queens, even though now not considerably greater than employees from WE-queens.

Why are employees from QE-queens larger?

One risk is that they’re extra ‘horny’ to nurse bees, so get extra consideration and are fed extra, or extra steadily, or each.

While this can also be measured (you want to make use of an statement hive, barcoded employees and a ‘shedload’ of symbol research) another technique is to switch in the future previous larvae into queen cells after which quantify the quantity of royal jelly that accumulates within the cells over a 48 hour length. Extra ‘horny’ larvae will likely be fed higher quantities of royal jelly.

Larvae from QE-queens collected considerably extra royal jelly than larvae from WE- or 2L-queens.

And, via logical extension, if eggs laid via QE-queens gained higher feeding you can be expecting queens reared from those well-fed larvae would grow to be larger queens … and so they do.

Queen dimension

To steer clear of confounding this a part of the research with the – referred to now – variations in queen dimension from eggs laid in queen cells, employee cells or from 2 day previous larvae, the authors used same old queen rearing ways – grafting 2 day previous employee larvae derived from QE-, WE- or 2L-queens – from same old employee cells into queen cups.

Queens reared from employee larvae laid via QE-queens have been considerably higher – outlined via thorax period and width – than queens from in a similar fashion elderly larvae from both WE- or 2L-queens. Disappointingly, they didn’t quantify different helpful parameters equivalent to weight or ovariole numbers .

OK, so the place are we?

That’s so much to take into accounts.

Like many experiments, the consequences don’t seem to be completely ‘minimize and dried’ … there are a couple of bizarre discrepancies, and one or two experiments will have to had been repeated to get extra statistically powerful information. The strategies and effects on royal jelly quantification are contradictory and really poorly described; I’ve carried out my highest to interpret what was once carried out.

I’ve unnoticed solely dialogue of the differential gene expression within the unique Wei et al., (2019) paper and the extra intensive research of gene methylation reported within the comparable He et al., (2021) learn about. Suffice to mention, when QE-queens have been when compared with WE- or 2L-queens there have been vital variations in:

“… mTOR, MAPK, Wnt, Notch, Hedgehog, FoxO, and Hippo signalling pathways which might be thinking about regulating caste differentiation, replica and longevity.”

Which, the cognoscenti  will respect, is precisely what you can be expecting, and and is the reason most of the phenotypic variations within the ensuing queens.

And, although you’re now not a member of the cognoscenti, I’m hoping you’ll be able to benefit from the names of genetic keep watch over pathways like Hippo and Hedgehog.

What are the conclusions and implications of this learn about?

Conclusions

The primary and maximum necessary take house message is that queens reared from eggs laid in queen cells are normally larger and higher than the ones reared from employee cell-derived eggs. Moreover, they’re all the time larger and higher than from queens reared from two day previous employee larvae.

We’ve lengthy identified that ‘previous’ larvae are a deficient beginning subject matter for prime quality queens, however the advantages – relating to fecundity and possibly different traits now not (but) measured – of eggs laid in queen cells over the ones laid in employee cells is new.

This can be a maternal impact and – amazingly taking into consideration the collection of research on their replica – it’s the primary transparent proof that it happens in honey bees. It sounds as if research from 50 years in the past advised that there was once a courting between egg and queen dimension, however the 2019 paper via Wei and co-workers confirms it.

This maternal impact is now not limited to progeny queens. Staff that broaden from eggs laid in employee cells via QE-derived queens also are higher high quality, a minimum of founded upon the restricted research performed.

This maternal impact most likely advantages all the colony.

Large, wider, widest

Queens can resolve the adaptation in dimension between employee and drone cells the use of their forelegs. They use this to selectively lay unfertilised eggs in drone comb. In all probability a equivalent mechanism operates to spot queen cells?

However realizing the dimensions of the mobile is best part the tale … can queens additionally measure huge or small eggs ahead of oviposition, selectively laying huge eggs in queen cells?

However, and perhaps extra realistically, most likely queens pause ahead of egg laying after they discover a queen mobile? It’s identified that behind schedule oviposition leads to larger eggs with extra yolk protein.

Implications for queen rearing.

Grafting-based queen rearing strategies – which account for the majority commercially reared queens – use decided on day-old employee larvae. As proven above, those most likely produce inferior queens to these reared from eggs laid in queen cells … inferior as outlined via dimension, ovariole quantity and within the high quality of eggs and brood they produce.

Repeated rounds of grafting-based queen rearing could be anticipated to have a cumulative and long-term deleterious impact at the high quality of the queens, and the colonies that they head.

How do you assume the final queen you bought was once reared?

And what was once her mom reared from?

And her grandmother?

What about her great-grandmother?

Sure, virtually indisputably, from grafted day-old employee larvae.

Implications for inexperienced persons

Grafting, or the perceived want to graft, is without doubt one of the primary disincentives preventing inexperienced persons making an attempt to rear their very own queens.

Alternatively, if higher queens actually are created from eggs laid in queen cells, it means that trade strategies will have to be used that don’t contain grafting.

This will have to inspire one of the crucial grafting-averse beekeepers to start out rearing queens.

That, and the strategies concerned, would be the matter of every other submit in this matter.

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Notes

Since I’ve already drafted portions of the 2 follow-up posts to this newsletter (and don’t have any aim of both writing one thing other or regurgitating them of their unfinished state as responses to feedback!) please center of attention at the major conclusions of those research in any feedback, moderately than the prospective implications, in particular for inexperienced persons. The identity of a maternal impact is necessary for our working out of honey bee reproductive behaviour.

References

He, X.J., Wei, H., Jiang, W.J., Liu, Y.B., Wu, X.B., and Zeng, Z. (2021) Honeybee (Apis mellifera) Maternal Impact Reasons Alternation of DNA Methylation Regulating Queen Building. Sociobiology 68: e5935 https://doi.org/10.13102/sociobiology.v68i1.5935.

Pan, Q-Z, Wu, X-B, Guan, C. and Zeng, Z-J (2013) A brand new manner of queen rearing with out grafting larvae ABJ 153(12):1279.

Wei, H., He, X.J., Liao, C.H., Wu, X.B., Jiang, W.J., Zhang, B., et al. (2019) A Maternal Impact on Queen Manufacturing in Honeybees. Present Biology 29: 2208-2213.e3 https://doi.org/10.1016/j.cub.2019.05.059.

Yu, L., He, X., Shi, X., Yan, W., and Wu, X. (2023) Honey bee maternal results give a boost to employee efficiency and reproductive skill in offspring. Entrance Mobile Dev Biol 11: 1156923 https://doi.org/10.3389/fcell.2023.1156923.