“There are two of them!” My daughter-in-law was trotting towards the house, her grin leading the way. She was tickled pink at the sight of twin calves in the pasture. Wayne, however, didn’t share her enthusiasm as he crawled out of the cab of the truck. Lacy is new to dairy farming, but Wayne knows that twins on a dairy farm aren’t the harbinger of good news. His reaction tempered her enthusiasm, but only a little. He handed me the bag of nails he had went to town for, and he and Lacy headed to the dry-cow pasture to have a look at the new arrivals.
Twin births in dairy cattle aren’t rare enough to warrant a camera crew, but they don’t happen all that often, which is good. Twin calves come with fertility problems ranging from reduced fertility to sterility due to anatomically abnormal reproductive organs. For dairy farmers, this is exactly the sort of problem they don’t need. Twins on a dairy farm are a bane, not a boon.
As twin (or triplet) fetuses begin to develop and grow in the cow’s womb, their placentas can touch. The joining of placentas between two male or two female fetuses doesn’t present much of a problem. While it’s likely that their fertility rate will be lower than others in the herd, it won’t be a complete wash. You wouldn’t use the males for breeders anyway, and the net result for the heifers will be nothing more than an extra cycle before a pregnancy occurs. Sometimes, a twin cow will have issues breeding back after she calves. While decreased fertility certainly isn’t welcome, it’s not nearly as bad as sterility, which is exactly what you have most of the time with male/female births.
Lacy with one of the twin calves.
Veterinary experts from the State University of New York at Canton claim that when a twin pregnancy occurs, the result will be a male/female pair 43% of the time. The female twin of a cow/calf pair is called a freemartin. Freemartins are sterile 92% of the time.
Most large producers just ship male/female pairs off to the beef auction. However, if you end up with a male/female pair, and you’re a glass-half-full sort of person, there are ways to tell if your female is a heifer or a freemartin.
- Do a complete, objective examination of the female twin. If she is larger than the male, this may be a sign that she was the first conceived, which some believe increases the chanes you have a breeder.
- Notice if the cow cleaned with one or two placentas. Touching placentas will often form into one, ensuring a freemartin. If there are two distinct placentas, the female calf may well be fertile.
- Examine the female’s navel area and from there slide your hand towards the area where a scrotum would be on a male. Feel around for an extra opening or protrusions; both indicate a freemartin.
- Move the tail and examine the vaginal area. Freemartins often have a longer distance from the vulva to the anus, with the vulva being undersized or missing. Often the vaginal opening will be covered with long hairs.
If the female passes the initial exam, the next step is to confirm that she has a reproductive tract. Freemartins have short vaginas. Even if all appears normal from the outside, an internal examination is a must. Measure the length by gently inserting a lubricated 100x15mm test tube into the vagina. The lubricated tube should slide freely upward for a few inches before slanting in a more downward direction with no resistance, just a change of direction. If the tube doesn’t slide in more than a couple of inches, you most likely have a freemartin. (Both the test tube and lubricant are readily available where veterinarian supplies are sold.)
After passing a physical, there’s one more test that can determine whether or not you are the proud owner of a fertile heifer. The Veterinary Diagnostic Laboratory at the University of Minnesota tests blood samples to determine if suspected freemartins are actually breeding heifers. The calf must be at least two-weeks old. The cost is $61 and takes two-to-seven days to get results. For information on how to submit samples to the lab, visit www.vdl.umn.edu/ourservices/otherpcr/home.html, or call 612-625-8787.
In addition to the fertility conundrum, twins complicate the birthing process. “Depending on how the twins are placed, there can be all kinds of birthing issues. If there are separate placentas, the calves can get tangled in the umbilical cords and strangle,” explains Wayne.
“After calving with twins, there’s a real problem with retained placentas and milk fever; there’s also a greater chance for ketosis with twin births. There may not be enough colostrum for both. Cows take longer to recover from a twin birth. It just sucks the energy right out of them. If she ends up with ketosis after twins there’s a greater chance of a displaced abomasum (DA). If she goes off feed, there’s nothing to stabilize her stomach. There’s already a huge void where the calves used to be, and now her stomach is empty too. It’s not long before you have a twisted stomach.”
A couple of years ago, one of our cows, a Brown Swiss named Swiss Miss, died after calving with twins. Both calves struggled to be born at once, entangling their legs and requiring manual repositioning. Wayne knew there was a huge problem when he saw three legs, and advises those who don’t have experience with complicated birthing situations to call a veterinarian. Swiss Miss suffered a retained placenta, had damage to her uterus, and came down with milk-fever. After two weeks of a lukewarm recovery, she came down with ketosis and didn’t recover.
Twins arent always a good thing, especially in calves.
“She was an older, heavier cow,” explains Wayne. “I’m pretty sure a normal pregnancy would have been no problem for her, but she was in no shape for twins. Too bad I didn’t have the vet do an ultrasound on her. You can’t tell just by looking at the cow whether or not she’s carrying twins. She could be carrying a large bull calf and be huge, or she could be carrying two small female calves and be a normal size. Looks are deceiving.”
This time, Wayne did have the veterinarian do an ultrasound, but she didn’t pick up the twin. While veterinary technology has come a long way, Mother Nature still pulls off a surprise now and then.
Wayne advises all cow owners to keep a couple bottles each of calcium and dextrose on hand to treat cows after complicated births. “If she comes down with milk-fever, it’ll be within five days of calving. I give her 750ml of a 23% calcium solution intravenously. You can put the calcium solution under the skin, but it takes longer to get into her system. If you put it in a vein, she is better in a matter of minutes. Cows can also come down with ketosis a couple of weeks after a hard birth. They just run out of energy. For ketosis I give 500ml of dextrose in a vein. Dextrose has to be in the vein, not under the skin, to work.”
“You should keep calcium and dextrose on hand, even if you don’t know how to administer them,” he cautions. “If you have to call the vet, they’ll charge you if they have to use their own supplies. If you have some available, they’ll use yours. It’s cheaper.”
Unlike our previous experience with twins, this delivery went fine. Lizzie recovered nicely and continues to graze contentedly. Wayne sold the male twin, but after much cajoling from Lacy, he decided to keep the female. Her name is Hope, and Wayne plans to have our veterinarian examine her during the next scheduled herd health visit. He thinks Hope is a breeding heifer. If the vet agrees, he’ll have her send a blood sample to University of Minnesota to find out for sure. Granted, there’s only an 8% chance that she’s not a freemartin, but around here, the glass is always half-full of frothy whole milk, chilled to perfectionand there’s always more where that came from.