Freemartin?

[aisha3789]

Got this doe 6 weeks ago and the owner didnt give any information. Not sure if she was bred or not. She never came in heat in this six weeks. We have a young buck with her and he tries to mount her. A friend said she might be a freemartin. Her anatomy looks normal to me. What do you think?

 

[Southern by choice]

Freemartins are extremely rare in goats. It is really a cattle thing.
She is probably bred if she hasn't come in to heat. No way of knowing unless you do a pregnancy test or ultrasound.

 

[rosti]

SBC, may I ask what your definition of a freemartin is, and if it’s different than a (pseudo)hermaphrodite?

 

[Southern by choice]

From what I understand is the in cattle when twins are male and female the female will be sterile. Basically renders the ovaries infertile.
Hermaphrodite is where both male and female organs are present.

In goats male and female twins are the norm and does not cause infertility. (referred to as free martin)
Hermaphrodites do occur in goats... Many years ago it was thought breeding polled to polled increased the risk of this however studies since then have not shown that to be true. Yet the original study from 80 years ago had so many eliminating polled genetics out of fear and those that kept polled continue the no poll to poll breeding.
So much so that few do it because of the stigma. That is why we don't.

 

[farmerjan]

In cattle, @Southern by choice , is basically right. A male and female twin will cause the female to be sterile about 90% of the time. There are different thoughts as to why, but the one I most often hear, and have no reason not to believe, is that the male embryo actually starts to develop a little faster, causing male hormones to suppress the female developing embryo. This often causes the female to have incompletely formed reproductive tracts. Sometimes missing a uterus, part of the fallopian tubes, part of the vagina, missing ovaries, some pieces not completely formed or missing completely. I also am of the belief that it occurs much more often when there are 2 eggs released and fertilized by the semen in the same horn. If eggs are released from both ovaries, and the placentas do not actually embed in the uterus in the same area, they seem to be more likely to have a chance to be good. Sometimes this can be seen with ultrasound, as to where the embryos are located in the uterus. Often the female will not be as good a milker as she would normally be if a single.... but that has never been studied enough to be proven.
I test for one dairy that has an amazing number of twins (m/f) where the females have been perfectly functional. They are currently milking 3 "free martins" (which of course they are not really free martins), right now. But nearly all the dairies that have a set of mixed twins will just sell both as it is not worth raising up a female that will very likely be "useless". We do not keep any "free martin" twin heifers in our beef cows when born. They are sold as feeders.
You do not see that in pretty much any other mammal that I am aware of. Sheep & goats have multiple mixed sets of offspring with few problems. Hogs have multiple pigs of both sexes. Even horses that have twins, while not that common, and definitely not preferred, that have a mixed set, they both are usually fertile. Dogs, cat, mice, guinea pigs, rabbits, you name it, that have "litters" of babies do not seem to have this "problem".

 

[rosti]

Okay, just wondered. Some people call everything hermaphrodites, and deny that freemartins even exist in goats.
I had never heard of a freemartin goat, but since learning last fall that I have a freemartin goat, posts on FB have indicated that it isn’t quite as rare as I, having never heard of it in goats, would have thought.

 

[Southern by choice]

In cattle, @Southern by choice , is basically right. A male and female twin will cause the female to be sterile about 90% of the time. There are different thoughts as to why, but the one I most often hear, and have no reason not to believe, is that the male embryo actually starts to develop a little faster, causing male hormones to suppress the female developing embryo. This often causes the female to have incompletely formed reproductive tracts. Sometimes missing a uterus, part of the fallopian tubes, part of the vagina, missing ovaries, some pieces not completely formed or missing completely. I also am of the belief that it occurs much more often when there are 2 eggs released and fertilized by the semen in the same horn. If eggs are released from both ovaries, and the placentas do not actually embed in the uterus in the same area, they seem to be more likely to have a chance to be good. Sometimes this can be seen with ultrasound, as to where the embryos are located in the uterus. Often the female will not be as good a milker as she would normally be if a single.... but that has never been studied enough to be proven.
I test for one dairy that has an amazing number of twins (m/f) where the females have been perfectly functional. They are currently milking 3 "free martins" (which of course they are not really free martins), right now. But nearly all the dairies that have a set of mixed twins will just sell both as it is not worth raising up a female that will very likely be "useless". We do not keep any "free martin" twin heifers in our beef cows when born. They are sold as feeders.
You do not see that in pretty much any other mammal that I am aware of. Sheep & goats have multiple mixed sets of offspring with few problems. Hogs have multiple pigs of both sexes. Even horses that have twins, while not that common, and definitely not preferred, that have a mixed set, they both are usually fertile. Dogs, cat, mice, guinea pigs, rabbits, you name it, that have "litters" of babies do not seem to have this "problem".

Okay, just wondered. Some people call everything hermaphrodites, and deny that freemartins even exist in goats.
I had never heard of a freemartin goat, but since learning last fall that I have a freemartin goat, posts on FB have indicated that it isn’t quite as rare as I, having never heard of it in goats, would have thought.

@farmerjan I wonder if the $50 would be worth it to find out (in cattle) but it is a high %.
Just an FYI- VGL (UC Davis Veterinary Genetics Lab) offers a DNA test for Freemartin in cattle and in goats (blood, not hair sample is required) for $50.

QUOTE- www.vgl.ucdavis.edu
"Freemartin Testing - Goat
A freemartin is defined as a female that is born as a twin with a male and is sterile as a result of exposure to masculinizing hormones. A connection between the two fetal circulatory systems develops early in gestation (anastomosis) and leads to the exchange of blood between the fetuses. Exposure to male hormones leads to underdevelopment of the female's reproductive tract. Incidence of freemartinism in goats is generally low (less than 1%), increased risk has been observed when litter sizes are four or more. Other intersex phenotypes in goats can result from effects of the polled gene. A DNA test that detects presence of Y-chromosome is available to confirm chimerism in the blood of females suspect of being freemartins."

Freemartin Testing - Cattle
A freemartin is defined as a female that is born as a twin with a male and is sterile as a result of exposure to masculinizing hormones produced by the male. A connection between the two fetal circulatory systems develops early in gestation (anastomosis) and leads to the exchange of blood between the fetuses. Exposure to male hormones leads to underdevelopment of the female's reproductive tract. Over ninety percent of females born co-twin to male are infertile. "

 

[farmerjan]

For us it is not worth the money. Especially not with the depressed cattle markets now. Yes, if it was a planned breeding, with registered animals that I desperately wanted a female from..... One purebred holstein breeder that does alot of ET's and selling females, will ultrasound for sex and if it is not the sex he wants, will Lute and start over when the cow comes back in heat. Same for twins, will always Lute and not have to deal with the likely non-fertile female.
What I do with the dairy females that are twins to a bull, I will keep them because they aren't worth anything at the markets anyway. Then at several months, up to breeding size, the vet can pass a rod as if breeding and often find they are at a dead end.... or palpation can often feel if there are parts of the tract missing. These females usually do make good heat detectors for other cattle, and we put them in the freezer so not a loss. The beef heifers aren't worth it because we seldom eat any "beefcattle" beef, mostly dairy beef. They just get shipped. Many beef heifers are going to places where they are run on grass/wheat/hay or whatever and then put into feed lots. Someone who buys heifers to feed out to breeding size, does so with the idea that there will be a percentage that will not breed/settle for whatever reasons. Goes with the territory.

 

[Mini Horses]

While there is an established "usual" blood supply causative for this, we all know that ANY animal can have developmental issues. It is, as @farmerjan has stated, often the decision to "deal" with the possible problem based on values and goals for the animal & breeders herd goals. With meat animals strictly for slaughter, it isn't a huge problem.

Just as horses rarely have twins, most cattle are single births. The few who are not you deal with. Goats prominently have twins & few issues. Mini horses and dwarfs were problems often "covered" up by disposal of get. Finally, a mini farm owned by a vet, promoted a huge effort to find causes.

UC Davis has, for many years, been very active in many reproductive research trials and tests. They worked with genetic detectors for dwarfism in minis to help identify the traits. Also chimerism detection and issues, plus color genetics, overo traits & deaths. It's all pretty interesting. These things are often overlooked by "owners" who have occasional breedings but, anyone breeding animals with known problems, for a profit, will be reading all they can!

 

[greybeard]

Some breeds of cattle are more likely to twin than others,with dairy breeds more likely than beef breeds...most of the time.

This table is a little 'old' but the newer studies show about the same results.