Way more males than females!

[KelleyBee]

Is this normal for rabbits? I have a buck whom I just bred for the first time over the last few months. He’s produced 3 litters, a total of 17 kits, (3 died shortly after birth). Of the 14 living, 10 are male! Only 4 female! I’m surprised by this. I’ve always been under the impression that females were more plentiful in birth rates. Is this general understanding void for rabbits? Do rabbits typically have more male offspring?

 

[Preitler]

It's just statistics that plays tricks with our mind. It needs much larger numbers to quite likely get an average, it's like casinos make money with people thinking they are on a streak at rolling dice or roulette.

Your numbers are normal and not a sign of anything, I wouldn't talk about a trend before that ratio doesn't start to even out after min. a hundred kits. And even that would be statistically possible and no proof that something is off.
I know the wiered experience of sexing single sex litters, started over and over again and got a second opinion...

I don't know about rabbits, but with some mammals there are environmental factors that can influence the ratio, don't think that comes into play in an average rabbitry.

 

[Rabbits by Accident]

I don't know about rabbits, but I was wondering the same thing. I just got back into rabbiting and one young doe had 4 kits 50/50 male/female. The second very large doe had 9 kits - 7 does 2 bucks.

There are various things that can influence human fertility and I'm curious what factors can influence rabbits - ambient temperature? age of rabbits? acidity of diet? Interesting to find out.

Since the rabbits were preggers when I got them, I have no idea on any of that. Don't even know if the same buck was used. But it is definitely curious.

Liz

 

[Preitler]

As I said, an equal number is actually a statistical oddity. We, with our biased human thinking, expect that, but it's not how things work.

 

[Rabbits by Accident]

As I said, an equal number is actually a statistical oddity. We, with our biased human thinking, expect that, but it's not how things work.

I agree, BUT - perhaps it is usually uneven because of an environmental influence. Perhaps if the acid is high, it produces more females, or vice versa. So one litter, you get more males, the next more females, but it is actually in response to a stimulus that one is not aware of.

 

[Preitler]

Good luck getting hard data on that

 

[northernnevadahollandlops]

I realize my numbers also are not statistically significant, but of six litters and 35 kits, only 10 of ours were confirmed female (21 confirmed male, others died before sexing). I have heard that adding apple cider vinegar to the does drinking water will increase the likelihood of female kits. Anyone have any experience with that?

 

[Preitler]

ACV was a hype some time ago, all kinds of close-to-magic got ascribed to it - this is a new one. That would mean it would be able to mess with mammal hormones, way more effective than those toxins in plastic, and we put it on our salad?
Only thing it actually seems to be able to do is to attract fruit flies. Good thing is, it doesn't hurt to try, for whatever reason, and costs close to nothing.

 

[hotzcatz]

There have been litters of all females, there have been litters of all males. If you get the numbers high enough, then it all averages out more or less.

 

[Rabbits by Accident]

It has nothing to do with hormones. There are environmental factors that can influence which sperm fertilizes. There were studies on it with humans. The problem is figuring out what exactly does it LOL Acidity was one of the factors. So there could be some truth to the ACV, however whether it actually impacts the acidity of the uterus I don't know.

When I say environments I mean the internal environment of the rabbit for instance a hot bath will lower the fertility of a male human. So don't put your rabbits in a hot bath LOL

I was thinking that high value food could also influence it - if there's more food maybe it would swing toward more females so that they could breed whereas when food is scarce maybe more males which could feed something else LOL

The rabbit that had 7 females out of 9 kits had been fed a lot of carrots because the guy was lazy. But then, the one that had 2/2 was probably fed carrots too LOL

The issue is whether you could actually influence any of this.

Maybe I should stock up on carrots lol

Liz

 

[Rabbits by Accident]

I realize my numbers also are not statistically significant, but of six litters and 35 kits, only 10 of ours were confirmed female (21 confirmed male, others died before sexing). I have heard that adding apple cider vinegar to the does drinking water will increase the likelihood of female kits. Anyone have any experience with that?

Contrary to my last comment, seems like lower quality food creates girls LOL.

"Breakfast Cereal and Sex Selection
In a study published in the Proceedings of the Royal Society B, 740 newly pregnant British women recalled what they ate the year before conception. Those who ate breakfast cereals and potassium-rich foods and consumed more total calories daily delivered more boys compared to those who skipped breakfast and ate fewer total calories." (From WebMD)

So maybe an inadequate diet of carrots did have something to do with it.

Liz

 

[RabbitsOfTheCreek]

Maybe I should stock up on carrots lol

Liz

Actually, my rabbits don't even eat carrots. Even though many people will say that a rabbit's favorite food is carrots, they don't usually eat them. Other things like lettuce, watermelon, and raspberries are better.

 

[eco2pia]

Ok, I am with @Preitler on this--I have had hundreds and hundreds of litters of various small mammals in my line of work, probably thousands. In the last decade, I have seen it all, perfect 50/50 splits, huge litters or tiny litters of all one gender, even timed litters (all bred at the same time, all born at the same time) with 90/10 split.

It really really is statistics, we say something is 50/50, but that is across thousands of attempts. I have even seen individuals swing from one end to another of the offspring-gender spectrum in super controlled lab environments--even if something was in their environment, their environment NEVER changes, but their litter gender ratio did. This is just one of those things the human brain struggles with, we are built to look for patterns, but they are not always real.

 

[Preitler]

It has nothing to do with hormones. There are environmental factors that can influence which sperm fertilizes. There were studies on it with humans. The problem is figuring out what exactly does it LOL Acidity was one of the factors. So there could be some truth to the ACV, however whether it actually impacts the acidity of the uterus I don't know.

No, it doesn't.
It's just that female sperm is actually somewhat hardier, so those manage better under different environmental stress, like radiation, heat or acidity. Malnutrition, like after the war, might actually play a role. But a miniscule amount of vingar is easily compensated, our bodies are very good at keeping Ph levels where they should be. The vingar goes into the stomach, where the acidity is magnitudes higher anyway.

The study you mentioned, well, IMHO it's pretty much worthless. It has much more to do with what people remember than influence on fertility. An equal number would have been quite unlikely. Sad but true, a lot, if not the majority of such studies, on that level are not worth the pixels on the screen.

As @eco2pia said - it's our need to see patterns in everything.

 

[Lewis]

Contrary to my last comment, seems like lower quality food creates girls LOL.

"Breakfast Cereal and Sex Selection
In a study published in the Proceedings of the Royal Society B, 740 newly pregnant British women recalled what they ate the year before conception. Those who ate breakfast cereals and potassium-rich foods and consumed more total calories daily delivered more boys compared to those who skipped breakfast and ate fewer total calories." (From WebMD)

So maybe an inadequate diet of carrots did have something to do with it.

Liz

Interesting! Can you send a me a link to this study?

 

[Rabbits by Accident]

Interesting! Can you send a me a link to this study?

https://www.webmd.com/baby/features/deciding-babys-sex#1
I don't think the study was a great study, I really just shared it to point out that scientists know many, many things influence what sperm fertilizes the egg(s) - possibly something as bizarre as what you eat for breakfast LOL. That wasn't the page I read the first time, but it's what came up when I searched. If you search you may be able to find the original page I had which had other studies mentioned.

 

[White's family farm]

I've only been at this a couple years, so I can't give the stats assurances other people can. I will say that my broken buck has consistently sired 75-80ish% broken offspring with solid does (should be 50/50).

That's only been across 6 litters so far, but all were 8+ kits each.

So it MIGHT be possible that the buck has something to do with it if you keep getting that kind of discrepancy. I wouldn't know for sure though.

 

[Rabbits by Accident]

Ok, I am with @Preitler on this--I have had hundreds and hundreds of litters of various small mammals in my line of work, probably thousands. In the last decade, I have seen it all, perfect 50/50 splits, huge litters or tiny litters of all one gender, even timed litters (all bred at the same time, all born at the same time) with 90/10 split.

It really really is statistics, we say something is 50/50, but that is across thousands of attempts. I have even seen individuals swing from one end to another of the offspring-gender spectrum in super controlled lab environments--even if something was in their environment, their environment NEVER changes, but their litter gender ratio did. This is just one of those things the human brain struggles with, we are built to look for patterns, but they are not always real.

Okay just another thought to muddy the waters LOL if you have 10 rabbits and five of them always have 100% girls and five of them always have 100% boys, then your statistics would be that your rabbits have 50% boys and 50% girls overall.