KIM'S KORNER: Getting the right angle on vaccinations
By Dr. Kimberly Vonnahme
Can you believe that the summer is almost over? What a wonderful time it is during the summer months at Harvest Hope Farm! The vegetables are growing—and so are our lambs! I have the unique pleasure of helping the Kotrba family with the critters on the farm—as an animal scientist, I love to see how we can better the world around us with animals! Caring for animals is a big responsibility and one that we are happy to do. Of course, we care for the animals all year round, but during the spring and summer months, we focus on the lambs. In the spring, we have our lambing season (when our lambs are born) and by the end of the summer, we are weaning our lambs (this is when our lambs no longer need their mother’s milk as their main source of nutrients). We make sure we provide them a clean and comfortable place to jump and play, we give them fresh water every day, and we provide some medicines to keep them healthy. We provide them with vitamins when they are born. And we vaccinate for 2 common diseases in sheep: overeating disease and tetanus.
Overeating disease, also known as enterotoxemia, is a major cause of death for lambs from birth through their entire feeding period. The bugs (or the bacteria) that cause this disease is Clostridium perfringens types C and D. When a lamb isn’t protected from this bug, it can suffer acute indigestion, convulsions, and other nervous system signs like colic and even sudden death. Lambs can be born as a singleton, or as a twin or triplet. Normally if a singleton lamb is nursing a ewe that is producing a lot of milk, they are more at risk of getting overeating disease. Also, later in life, if lambs are consuming a high energy diet, they can be at risk for overeating disease. We take great care at Harvest Hope Farm to provide our lambs with the proper feed and administering vaccinations so that this overeating disease can be controlled.
The other disease we vaccinate our lambs for is tetanus. Tetanus is a common, fatal disease in sheep that is caused by the bug (bacterium), Clostridium tetani. People are often vaccinated for tetanus, too! If a lamb (or person) gets tetanus, they can experience muscle stiffness and spasms, bloat, uncoordinated walking, panic, and/or the inability to eat and drink—this is often referred to as lockjaw. Death is inevitable, usually about three or four days after symptoms appear.
So where do these bugs (or the clostridial bacteria) come from? These bacteria are found all over the environment. We can easily find them in soil and manure (lots of those items are on farms!). Our sheep are called ruminants—that is they have a 4-chambered stomach that allows them to eat foods we can’t—like grass and other plant materials that our bodies can’t digest. Since our animals graze and eat grass, they are always coming into contact with clostridial bacteria—if we were to look, we would find these bugs in our sheep’s digestive tract. If our animals were not vaccinated and were to get sick or stressed for some reason, the lamb’s immune system would be weakened, and the clostridial bugs would take over and then we would get disease in our flock. The best thing we can do is to help the lambs by giving them a vaccine so their bodies can build up antibodies to these clostridial bugs—and if there is ever a time when they do get a little wore down—their bodies can still fight off the clostridial bugs from making our lambs so sick they can’t recover.
We have had a great lambing season at Harvest Hope Farm this spring! The lambs are doing very well—are super quick and love to jump around! Soon after the lambs are weaned, we will let the mama ewes eat “just for themselves again”. When the days get shorter, the ewes will begin to cycle—and we hope to be blessed with strong, beautiful lambs next spring. With the right angle on vaccinations, we will be able to keep those lambs healthy all year round!
Thanks for coming around to Kim’s Korner—where the right angle on animal science can always be found.
Kimberly Vonnahme, PhD, is a mother, lover of agriculture, and an animal scientist. Dr. Vonnahme was a professor at NDSU for 13 years before joining the animal health company, Zoetis. Kim enjoys making lists, analyzing data, hugging her husband and children, and a strong cup of coffee.