My last two columns have been about
sheep and goats, a subject of which I’m quite fond. I realize, though, that most of the readers
of this newspaper probably are not as interested as I am, so I thought today’s
topic should have a broader appeal. That
is why I decided to write about sex.
I was doing some reminiscing and
recalled an incident that happened a few years ago with one of my favorite
clients, a 40-something bachelor dairy farmer.
We were palpating some of his cows for pregnancy, and the sorry state of
his romantic life came up in our conversation.
Frank (not his real name) had had a
lot of girlfriends and dated a lot of women, but marriage eluded him. He came close once, though. A lovely girl, she was the love of his
life. Since he obviously was not married
to her, I asked him what happened. Frank
told me he dumped her because she couldn’t have kids. I asked him how he knew that. “Because she was a twin, and her twin was a
brother,” was his reply.
I paused for a moment; I didn’t know
whether I should tell him he might have made a tragic mistake or just let it
go. But, as a firm believer in full disclosure, I told him. “It doesn’t work
that way with people, Frank. She
probably would have been OK.”
“No kidding?”
“NO kidding!”
“Oh $#!& !” was his response and
the end of our talk on this matter, as I quickly changed the topic to baseball
or the weather so as not to dwell on his unfortunate decision.
What Frank was confused about is a phenomenon that occurs in cattle called “Freemartinism”. A freemartin is a heifer calf that is born a twin to a bull calf. The condition arises from a mixing of the calves’ blood, which occurs in the uterus, resulting in the masculinization of the female calf’s reproductive organs. She is rendered sterile. A small percentage of these heifers will be fertile, but it is so small that most farmers consider them infertile and treat them as steers. This condition occurs in cattle, but fortunately not in humans. Ladies, Frank is still available.
While on the subject of sex, a question frequently asked of veterinarians is, “What is a mule?” A mule is a cross between a male donkey and a female horse. The opposite cross, a mating of a male horse and a female donkey results in an animal called a hinny. Hinnies never gained much favor. They are not as strong as mules, their conformation is not as correct, and they are not as attractive. Yes, mules can be pretty.
Mules, being a hybrid of two
different species, are infertile – at least most are. Horses have 64 chromosomes, donkeys have 62,
and mules end up with 63. Since 63
cannot be divided evenly into chromosome pairs in the egg and sperm cells,
mules are sterile. There have been,
however, five documented cases of fertile mare mules in the United States
Researchers believe that the mare
mules’ eggs contained only horse chromosomes and were able to be fertilized by
the sperm cells from the stallion.
I learned another interesting tidbit
at a recent veterinary meeting. The
camelid family, which includes llama, alpacas, and bactrian and dromedary
camels, all share a common ancestor, which originated in the Sand Hills area of
Nebraska Northern South America . From there they divided into two groups – one
continued to move south and become llamas and alpacas, and the other group
turned and headed north across the Western United States, Canada, through
Alaska, and across the Bering Strait into Asia, where they became bactrian and
dromedary camels.
All of these camelids have the same
number of chromosomes (74), and can, therefore, interbreed.
That concludes our sex talk, for
this column. But remember, if you have
any questions of this nature, just ask your veterinarian – or your parents.
Author: Dr. John Jones
Image courtesy of africa at FreeDigitalPhotos.net
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