How many sperm are used to fertilise each egg?

[Truble]

If I've understood things correctly, sperm from each mating is passed along and up the oviducts which swell out with the all the sperm which is laid out sequentially from each mating. There's a picture somewhere in Mating Biology of the Honey bee (I think) where they used coloured sperm with II to show this. After the queen has fully mated she returns to the hive where contractions of the oviducts etc force the sperm back out of the vagina. In doing so it passes the duct to the spermatheca and each sperm has a chance to migrate through (appears to be debate whether passive [breslaus??? pump]...or active with most favoring active migration of sperm). So first and last mating's have a pretty equal chance of being equally represented.

 

[B+.]

If I've understood things correctly, sperm from each mating is passed along and up the oviducts which swell out with the all the sperm which is laid out sequentially from each mating. There's a picture somewhere in Mating Biology of the Honey bee (I think) where they used coloured sperm with II to show this. After the queen has fully mated she returns to the hive where contractions of the oviducts etc force the sperm back out of the vagina. In doing so it passes the duct to the spermatheca and each sperm has a chance to migrate through (appears to be debate whether passive [breslaus??? pump]...or active with most favoring active migration of sperm). So first and last mating's have a pretty equal chance of being equally represented.

The part you have missed is the role of the valvefold in creating a seal to the passage of sperm. This is what pushes the sperm up into the spermatheca as the lateral oviducts contract.
Is this the graphic you're referring to https://youtu.be/Wm7RqXJD4_w?t=3m36s ?

 

[Motobiman]

Thanks guys, getting clearer.

Except I don't understand your very last sentance, Truble.

if the passage into the spermatheca during the sperm rejection process relies on the 'activity' of the sperm then surely the more active sperm would be at an advantage and therefore better represented in the total content of the spermatheca?

For example each drone cannot possibly be equally represented in terms of either quantity or quality of sperm so it would be weird if the representation of sperm in the spermatheca was equal ie the same percentage for each drone.

Some process rather than sheer chance must be affecting the relative percentages of drone sperm in the spermatheca.

Could it be the relative strength in terms of swimming ability of the sperm in different ejaculations?

 

[Truble]

The part you have missed is the role of the valvefold in creating a seal to the passage of sperm. This is what pushes the sperm up into the spermatheca as the lateral oviducts contract.
Is this the graphic you're referring to https://youtu.be/Wm7RqXJD4_w?t=3m36s ?

It's very similar but the diagrams I remembered are on page 99 and 100(fig 10.2 and 10.3) in Koeniger Mating biology of the honey bee....thanks for making me look it up. Turns out I remembered wrongly as I thought it was II and they examined the spermatheca afterwards, but they didn't they filled small rubber balloons to look at the distribution.A different situation.

 

[Truble]

Thanks guys, getting clearer.

Except I don't understand your very last sentance, Truble.

if the passage into the spermatheca during the sperm rejection process relies on the 'activity' of the sperm then surely the more active sperm would be at an advantage and therefore better represented in the total content of the spermatheca?

You make a good point, worth pursuing further. But, if one assumed that most sperm where equally motile they would all have approximately the same window of time to enter the spermetheca as the sperm is discharged past the duct. Have you come across anything that says there are differences in motility in sperms from different drones (dead sperm excepted!)?

 

[Motobiman]

You make a good point, worth pursuing further. But, if one assumed that most sperm where equally motile they would all have approximately the same window of time to enter the spermetheca as the sperm is discharged past the duct. Have you come across anything that says there are differences in motility in sperms from different drones (dead sperm excepted!)?

No, but it's well documented in other animals so I see no reason why bees should be different.

https://hal.archives-ouvertes.fr/hal-01234717/document

Hmmmmm

Not sure I have the education to understand all of this . . . . .

 

[Truble]

As Bontbee suggested a re-read of Koenigers Mating biology explains all. I won't repeat verbatim but basically it says the unequal patrilineages are most likely due the sperm within the spermetheca not being thoroughly mixed. The paper I came across that I gave the link to implied that as sperm is used over the lifetime of the queen these inequalities even themselves out.

 

[B+.]

It's very similar but the diagrams I remembered are on page 99 and 100(fig 10.2 and 10.3) in Koeniger Mating biology of the honey bee.

Its hardly suprising. I think they both trained under Ruttner in Germany

 

[B+.]

Have you come across anything that says there are differences in motility in sperms from different drones (dead sperm excepted!)?

The only papers I have seen deal with motility over time, not between individuals

 

[Motobiman]

The only papers I have seen deal with motility over time, not between individuals

It would be an oddity in nature if there was no difference between different samples and even within a sample.

 

[B+.]

It would be an oddity in nature if there was no difference between different samples and even within a sample.

You should probably take a statistics course. A fundamental requirement is that there is no difference between samples in a population. Otherwise, you couldn't choose samples at random without there being a difference in the result. Of course, there may be differences in performance due to disease, nutrition, etc