Weird Question: Livebearers & Fatherhood

I know this may be a long shot and probably there is no definitive answer to it, so here goes nothing.
I know livebearer females can store sperm for months and have many broods from one hit.
Question: Does new sperm replaces old sperm? For example, lets say two yellow platies mated, the female stored sperm so most babies if not all should be yellow. If I get a red male platy and get him to mate with the yellow female platy, which already mated with a yellow platy and most likely has stored sperm from him, will the red platy's sperm take over or the yellow platy's sperm will remain until depleted a few months down the road?

I told you, weird question. I am just trying to do some selective breeding.

Thank you,
Joe

 

I don’t know about this one, but I suppose it is the fish choice, since they can choice to dispose it.

 

I don’t know about this one, but I suppose it is the fish choice, since they can choice to dispose it.

Oh really? I didn't know that. How cool.

 

Yes, fish are quite amazing!

 

I have no idea, but I am glad you asked because I want to know too!

Semi-relevant fact: Male pipefish will actually “abort” some of the babies developing inside them if a more attractive (stronger, bigger, healthier) mother comes along and offers up her eggs. I wonder if platies do anything similar?

 

I have no idea, but I am glad you asked because I want to know too!

Semi-relevant fact: Male pipefish will actually “abort” some of the babies developing inside them if a more attractive (stronger, bigger, healthier) mother comes along and offers up her eggs. I wonder if platies do anything similar?

That's so cool!

luckdown since you breed livebearers, do you have any experience with this?

 

emeraldking

 

A female with fertilized eggs won't mate again until she gives birth. As far as them storing sperm and then deciding to use new sperm, not quite sure it works that way, but it is a interesting topic.

 

From what I've seen it won't replace the old stored sperm, however you will see them switch over to the newer stored sperm in about 2 months or so.

That being said one of my newer females just gave birth to what seems to be a mix of the previous male and the one she's with now. I'm not sure if I've seen this happen before or not. I think I only noticed cuz of how drastically different the fry were.

I do believe they can choose which sperm to use to an extent. I say this because ive seen my girls mate with all 4 of my males in the tank but they typically only have offspring from the same one male each time. Which is the male all my females seem to choose each time.

 

From what I've seen it won't replace the old stored sperm, however you will see them switch over to the newer stored sperm in about 2 months or so.

That being said one of my newer females just gave birth to what seems to be a mix of the previous male and the one she's with now. I'm not sure if I've seen this happen before or not. I think I only noticed cuz of how drastically different the fry were.

I do believe they can choose which sperm to use to an extent. I say this because ive seen my girls mate with all 4 of my males in the tank but they typically only have offspring from the same one male each time. Which is the male all my females seem to choose each time.

That's very interesting. Thank you for your input.

 

New sperm replaces old, which is why you can place a female that has just given birth with a new male and have his sperm sire the next offspring - however it is a very short window for this to happen (around 24hrs) that the new sperm can replace the old, this is why you see females that are getting ready to pop being hounded by males looking to father the next spawn.
The females put hormones out into the water indicating when she is receptive to being bred by a male (aka when the sperm will be accepted and used), this hormone increases before she gives birth which causes the males to stalk her. If you are wanting a certain male to father the offspring, when/after the female gives birth you put her immediately with the male you want and he should be the father of the next offspring. (That is if you separate the female from the others to give birth, otherwise it is pretty much whoever gets to her first).

New females livebearers could have been bred to any male, even one that looks like your current male, or she could be supplying genetics that make it look like several males sired the offspring - it is really a mix up of current available livebearers unless you are buying a true breeding strain that hasn't been "contaminated" by another line.

 

I'd be guessing the offspring would be a mix of both (or more) fathers, like what happens with some other animals like dogs etc. (if say, 2 or more males mated with the same female one after the other, but not sure how storing sperm works / is replaced etc.).
But also, it would be almost impossible to tell by the color of the offspring, unless they are specifically line bred -eg. 2 yellow platies won't necessary produce any yellow offspring. Both yellow parents will likely carry genes for other colors, so you may get red, red and black, blue, orange or any other color offspring. But if the yellows came from a pure yellow line that produces only yellows, then you can expect yellow offspring. But then again, if a pure yellow breeds with another color (red for example), again, the offspring could be any color, you may not even get any yellow or red, their color genetics go back a long way so they could carry almost any colors.

 

New sperm replaces old, which is why you can place a female that has just given birth with a new male and have his sperm sire the next offspring - however it is a very short window for this to happen (around 24hrs) that the new sperm can replace the old, this is why you see females that are getting ready to pop being hounded by males looking to father the next spawn.
The females put hormones out into the water indicating when she is receptive to being bred by a male (aka when the sperm will be accepted and used), this hormone increases before she gives birth which causes the males to stalk her. If you are wanting a certain male to father the offspring, when/after the female gives birth you put her immediately with the male you want and he should be the father of the next offspring. (That is if you separate the female from the others to give birth, otherwise it is pretty much whoever gets to her first).

New females livebearers could have been bred to any male, even one that looks like your current male, or she could be supplying genetics that make it look like several males sired the offspring - it is really a mix up of current available livebearers unless you are buying a true breeding strain that hasn't been "contaminated" by another line.

Wow, that was very in depth and very interesting to read. Thank you very much for your help.

I'd be guessing the offspring would be a mix of both (or more) fathers, like what happens with some other animals like dogs etc. (if say, 2 or more males mated with the same female one after the other, but not sure how storing sperm works / is replaced etc.).
But also, it would be almost impossible to tell by the color of the offspring, unless they are specifically line bred -eg. 2 yellow platies won't necessary produce any yellow offspring. Both yellow parents will likely carry genes for other colors, so you may get red, red and black, blue, orange or any other color offspring. But if the yellows came from a pure yellow line that produces only yellows, then you can expect yellow offspring. But then again, if a pure yellow breeds with another color (red for example), again, the offspring could be any color, you may not even get any yellow or red, their color genetics go back a long way so they could carry almost any colors.

Yeah, I was thinking about the genes as well. Thank you for your input.