All producers aim to maintain the health of their herds. Because losses from sickness and death take a toll on cattle and producers alike, it can be helpful to periodically review farm biosecurity practices.
Let’s take a look at a couple of examples.
Two farms sent beef cattle for necropsies (autopsies) to the state veterinary diagnostic laboratory to determine the cause of death.
Farm 1 purchased some cattle from an online advertisement. When cattle were transported to the farm, they were separated from the main resident herd. About one week after arrival, numerous resident cattle became sick – several very sick. Some of these animals became sick overnight and died before treatment could be started. A few days later, several of the recently purchased cattle became sick, and some were lost.
Farm 2 purchased a bull from a known source with a similar, good herd health program. He was vaccinated against blackleg and 9-way (IBR/PI3/BVD/BRSV/Lepto5). The bull was placed directly with the cows that had recently calved. About two weeks later, calves displayed respiratory signs “overnight.”
What could have happened to contribute to disease introduction in these two instances?
It was realized that the “separation” on Farm 1 was a fence that would allow nose-to-nose contact between the new arrivals and the home herd, so it did not provide true isolation. Also, unfortunately, because there was no vaccination history for either the new arrivals or the home herd, these unvaccinated cattle were not protected from major diseases. Both bovine respiratory syncytial virus (BRSV) and Mannheimia haemolytica (a bacterial pathogen that causes severe acute lung damage) were detected in the necropsy case.
On Farm 2, the bull was purchased from a known and trusted farm, but the new owner did not take extra precautions of isolating the newly arrived bull from the resident herd. Although in this instance the cattle on both farms had been vaccinated against the major disease players, it is important to remember that there are other known viruses and bacteria for which a vaccine is not available. Although this bull appeared healthy, he may have been “subclinical” – incubating a virus and/or bacteria that the resident cattle had not been exposed to or vaccinated against.
COVID-19 has taught the importance of personal biosecurity: avoiding close contact (social distancing), washing hands often, cleaning and disinfecting surfaces, avoiding contact with sick people and staying home if we’re sick. Similarly, in cattle health, the greatest risk is introduction of new cattle and traffic between farms and operations.
It is a good time for all cattle producers to review biosecurity practices:
- Keep a closed herd as much as possible, purchasing bulls and all replacement animals from reputable sellers.
- Quarantine new arrivals for 21 to 30 days before allowing them to be placed with your cattle. Design the quarantine area to prevent cross-contamination between cattle. You need a double fence between groups, with at least 6 feet distance. The greater the distance between areas, the better. Do not share water troughs or other materials between the new animals and with resident cattle during the quarantine period. Consider a separate person to care for the new arrivals. If this isn’t possible, care for the resident animals first, then the new arrivals. Monitor the new arrivals daily for signs of disease.
- Keep all equipment, vehicles and clothing clean to decrease chance of microbial contamination. Keep a record of visitors to the farm, including feed trucks.
- Prevent manure contamination of feed and feeding equipment. Use different equipment to feed and clean pens. Avoid stepping into a feedbunk, as this can contaminate feed with dirt or manure.
- Develop a routine vaccination program. Work with your veterinarian to determine what is needed for herd health in your area. Keep reminders for vaccines and all preventive care in your calendar.
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Control diseases. Give specific consideration to:
- BVD (bovine viral diarrhea): Many bull sales will test the bulls for BVD persistently infected (PI).
- Johne’s disease: Purchase from a producer who has been actively, annually testing the herd with negative test results.
- Bovine leukosis: Purchase from a producer who has tested the herd with negative test results.
- Always approach online purchases as “buyer beware.”
- If cattle die for unknown reasons, consider having a necropsy (autopsy) done.
It is always a good idea to treat new arrivals like they do have a contagious disease. Isolate these new arrivals. This not only helps prevent disease spread but also helps the cattle adapt and be less stressed and therefore less likely to shed disease. When you visit other farms or locations with cattle and other animals, be sure to clean your boots/shoes/clothes after coming home and change into farm clothes before visiting your cattle.
Remembering all these biosecurity steps will help us achieve our goals of having healthy resident herds and successful businesses.
References omitted but are available upon request by sending an email to the editor.
