Christine Navarre, DVM, and extension veterinarian at Louisiana State University (LSU), discussed overall herd health practices during a Cattlemen’s College session.
Navarre said although there is not a specific herd health program to follow that works with every individual farm and location, there are general measures producers can practice to strive towards a healthy herd.
She stressed how important it is to evaluate your livestock annually, as well as have a non-biased individual look over your herd. Most cow-calf herds experience herd health issues—not diseases. Management is the most critical component of livestock health and many health problems will disappear after a proper nutrition program is implemented.
Herd health also isn’t simply implementing a vaccination program, Navarre said, but a little piece of the process.
“Don’t just try to vaccinate your way out of a disease problem,” she said, although prevention is much cheaper than treatment.
An example would be vaccinating for anaplasmosis. It can be a pricier vaccine, but the upfront cost will pay off in the long run. Clinically, the disease can account for one death per year, but sub-clinically can result in a 2-5 percent decrease in reproductive efficiency, and a 50-lb. loss in weaning weights of calves nursing subclinical cows. With a $10 cost per vaccine dose in a 100-cow herd, one dead cow and two less weaned calves will pay for the vaccine.
Navarre said a controlled breeding system is necessary to easily control herd health. Prioritizing processing cattle and using prevention products at the right time is easier to keep record of with a controlled breeding system.
There are six areas Navarre said can impact herd health: nutrition; parasite control; biosecurity; vaccinations; genetics; and stress.
Skipping on nutrition management for one year impacts the cow for years afterwards. When nutrition is optimized, so is health and production. A cow’s body condition score (BCS) affects conception date, dystocia, calf health, pre-weaning, and post-weaning calf performance. Thin cows have the most trouble calving and one of the biggest causes of calves not receiving enough colostrum is from a cow’s BCS or poor nutrition.
A cow’s BCS at calving is the most critical for her breeding back in the next season. In a two-year study conducted in Oregon, a BCS of 6 at calving resulted in less dystocia despite higher birth weights, heavier weaning weights, 11 percent more calves weaned, and a future pregnancy rate of 91 percent versus 79 percent in cows with a BCS of 4.
Navarre emphasized careful biosecurity measures and not to “attempt to chase a disease if you aren’t going to try to prevent it.” Show cattle that travel are more likely to put cattle at home at risk, so having no fence line contact between the two groups would help to minimize biosecurity risks.
An animal’s genetic makeup can help make an animal more resistant to a disease, Navarre said. Semex, a biotechnology company in Canada, tested cattle immunity status and high immune responders were shown to have higher genetic growth.
How you feed a cow during pregnancy can also impact a calf’s genetic potential.
“After a calf is born, there is only so much you can do to improve it,” Navarre said, “but you can do a whole lot more to make it worse.”
Navarre said a study done at Texas A&M University showed that stressors during pregnancy can lead to calf disposition issues. Stress can depress the immune system, so it is important for producers to practice ethical cattle handling.
For weaning, exploring options such as fence line weaning can help minimize stress in the calf. Stressed cattle are less likely to respond well to vaccines and will not breed back as easily. Practicing low stress cattle handling will not only lead to better reproductive performance and health, but also reduce shrink when loading.
Although every operation is different, general herd health practices can go a long way in the long run.
— Anna Miller, WLJ correspondent
