Freemartin ?

[Anonymous]

I understand that a freemartin can be produced from a bull/heifer twin.
what about just a normal signal delivery of a heifer can see be a freemartin? While on the subject of twins can anyone give me advice on Heifer twins or Bull twins will the be fertile or sterile later in life? I have always heard sale bull-heifer twins but was wonder about same sex twins. Any comments would be appreciated.

 

[Arnold Ziffle]

Same sex twins should be OK from the fertility standpoint assuming all else checks out. As to a heifer born single -- it is my understanding that there is always a remote chance that it could be a freemartin, for example if the cow had earlier on aborted a bull twin and you didn't even realize that the heifer was in fact twin to a bull.

 

[Anonymous]

freemartin's = some (Not all) females born with a male twin. I have bought twin dairy calves, because the dairy just didn't take the chance. That I've later sold as bred heifers, others were sterile. If you go to valley vet supply and search for R U A freemartin (I think that's what it's called) they sell (or did). It's a plastic measuring probe to use while they are still young to give you a good idea if it will be sterile. If you wait until they are older just have the vet do a pre-preg evaluation exam.

 

[dun]

Same sex twins should be OK from the fertility standpoint assuming all else checks out. As to a heifer born single -- it is my understanding that there is always a remote chance that it could be a freemartin, for example if the cow had earlier on aborted a bull twin and you didn't even realize that the heifer was in fact twin to a bull.

Correct. Lots of people don't understand the reabsorbed bull calf concept.
The twins will generally be a little smaller, less then optimum nutrition, as weanlings and even to a lesser degree as yearlings. By two they've pretty well caught up and by maturity they have caught up.
The only 100% way to tell if it's a freemartin before breeding them and having them calf, is a DNA test that UC Davis does.
The sings of freemartinism range from the most obvious, a hairy protrding appendage on the vulva to everything being normal except the ability to generate adequate hormones to maintain a pregnancy. The DNA test can be done at 6 weeks I think.

dun

 

[certherfbeef]

My Grandpa always said if the heifer was born first she would be a breeder. If the bull was born first name the heifer freezer. Worked out right on every set he ever had.

 

[Ellie May]

We have a herford cow that gives twins every year never fails. Free Martins are a heifer and bull calf. The heifer may or may not be sterile. We were gonna keep one of the heifers one year to see but accidentally sold her (whoops). So personally I don't know. But I do have a question. Does the twins come from the cow or bull, you know like the sex & color comes from the bull. Is it the cow or bull who throws the twins. We have a new bull so just wondering.
Ellie May

 

[txag]

you know like the sex & color comes from the bull. Ellie May

color is determined by both parents. not just the bull.

 

[Ellie May]

I figured cattle where the same as horses on color, because if a paint is bred to a solid horse if it's homo. or heter. can't think of which it is it will be a paint. Didn't know that. So what about twins?
Ellie May

 

[Anonymous]

We have a herford cow that gives twins every year never fails. Free Martins are a heifer and bull calf. The heifer may or may not be sterile. We were gonna keep one of the heifers one year to see but accidentally sold her (whoops). So personally I don't know. But I do have a question. Does the twins come from the cow or bull, you know like the sex & color comes from the bull. Is it the cow or bull who throws the twins. We have a new bull so just wondering.
Ellie May

That is a very good question? Iam not sure about bovines but in humans the egg splits after fertilization( Identical Twins) and then there are non -identical twins(Feternal) that come from two eggs and two sperm. So two answer your question it is mostly the cow, I think with just a little help from the bull.

 

[Anonymous]

Same sex twins should be OK from the fertility standpoint assuming all else checks out. As to a heifer born single -- it is my understanding that there is always a remote chance that it could be a freemartin, for example if the cow had earlier on aborted a bull twin and you didn't even realize that the heifer was in fact twin to a bull.

Correct. Lots of people don't understand the reabsorbed bull calf concept.

dun

I wonder how many of those are actually hermaphrodite (mixed sex) and not freemartins :?:

 

[nrs farm]

I understand that a freemartin can be produced from a bull/heifer twin.
what about just a normal signal delivery of a heifer can see be a freemartin? While on the subject of twins can anyone give me advice on Heifer twins or Bull twins will the be fertile or sterile later in life? I have always heard sale bull-heifer twins but was wonder about same sex twins. Any comments would be appreciated.

I have seen other posts where people wonder about same sex twins. The problem comes in cattle when you have opposite sexed twins in that the blood (hormones) mix between twins. I'm no expert by any means, but it doesn't matter if a heifer's hormones mix with another heifer. It doesn't matter if a bull's hormones mix with another bull. But when the heifer/bull twin condition is present the bull calf's hormones mix with the heifer and the heifer is then affected (freemartin). I only know of this mixing taking place in cattle by the way. I've heard some people say it "works" in other species (even humans) which is not true to my knowledge. Here's a question I have that someone can maybe answer...why doesn't the bull twin become affected?

 

[Beefy]

Ellie May-
All the bull does is determine the sex of the calf. the cow has XX chomosomes which is two female chromosomes and the bull has XY chromosomes (one female, one male). the female automatically gives the calf a X because thats all there is and the bull gives either a X or a Y depending on which sperm cell penetrates the egg, its a 50% chance. Color is more complicated. The bull has nothing to do with twins except he determines the sex. the cow either has two eggs which are fertilized by two different sperm cells (fraternal-can be either sex, look different, even can be fertilized by two different bulls!) OR she has one egg that divides after fertilization (identical).


NRSfarm-
The bull calf is affected by reduced fertility just not sterile.


This brings to mind a discussion we had in my Reproductive Physiology class several years ago about a village in South America (i think) that had several cases of girls turning into boys when they hit puberty. When they hit puberty, the rapid increase in testosterone levels caused the girls' clitoris to develop into a penis.

SO, when you think youve had a bad day..