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What is the probability a cow will have twins?

Today is my 100th doodle! (I accidentally typed another 0 at the end of that and felt incredibly shocked at the vastness of the number). Probably would have been a perfect day for a vlog post... I'm not doing nearly as well in that department. Room for improvement. Actually, I do feel pretty shocked, 100 days of painting and researching and blogging, it's going to make for one heck of a project. It's almost a cryptic journal of sorts. There are stories behind the doodles... a lot of birthdays too:) The Doodles will help me recall the day's events leading up to the question. Of course a notable day would get a notable story. Are you ready for it? Ok, here is the story about how we came upon today's Daily Doodle:

So a couple special twins have birthdays today, and a cow, belonging to my sweet baby nephew Bridger, had twins today! Twins are fun aren't they? so mysterious and super cool... I'm sure I'm biased... But really, there has been interest in multiple births probably since... time... So, one might wonder what the probability is to have twins? Now, are we going to ask about people or calves? I mean the obvious choice would be to do both... two... twins... get it? But who wants to be obvious... or paint two baby calves and two baby people?! Today we will figure out what the rarity is of Bridger's cow having twins.

Estimates of the percentage of beef cattle births that produce twins vary. One of the more famous examples – reported in Hoard’s Dairyman, 1993 – puts the percentage at just below 0.5 percent or one in every 227 births. Research indicates approximately half of the sets of twins should contain both a bull and a heifer calf. According to a dairy cow site, the percentage is much higher, at around 5% (though the woman reporting said her farm is about double that percentage).

The wild thing is there is an actual name for a heifer (female) born with a bull (male) calf. They are called Freemartins. Freemartinism occurs when a heifer and bull calf are born together. A freemartin is over 90% likely to be sterile. When a heifer twin shares the uterus with a bull fetus, they also share the placental membranes connecting the fetuses and causing them to transfer unique characteristics. The males are rarely affected by infertility.

For this reason, it's requested cattle owners make specific notes when their cows have twins in case a freemartin is discovered and ensures they aren't used as a replacement heifer in a herd, because that probably wouldn't go very well.

What do you think? Are twins cuter than singles??

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