Disease does not discriminate against how it travels; it only seeks to find a new host. That’s why biosecurity efforts must encompass everyone who steps foot on a dairy farm. Any new animal, vehicle, clothing, person, or piece of equipment that arrives could potentially be carrying a pathogen that threatens the health of your animals.

A critical piece of protecting a farm against disease is understanding how it spreads, said Hayley Springer, an Extension veterinarian, during a Penn State webinar. She outlined that “everyday” biosecurity efforts must recognize that disease can move in any of the following ways:

  • Vector-borne. Ticks and flies are common causes of diseases including pinkeye and mastitis. Controlling these pests will go a long way in preventing infections.
  • Iatrogenic. This term refers to disease or illness caused by medical activity. An example in cattle is anaplasmosis, a disease of red blood cells that can be transmitted between animals. “One of the most common ways we transfer disease in an iatrogenic way is through the reuse of needles,” Springer explained.
  • Direct contact. Bovine viral diarrhea is an example of a disease spread directly. Here, Springer stressed the importance of vaccination.
  • Fecal/oral. These diseases are spread directly through manure and may enter another animal through the mouth. E. coli and salmonella are two examples.
  • Aerosol. Adequate ventilation is critical in limiting the spread of diseases such as bovine respiratory disease.
  • Fomite. Inanimate objects like boots or tractor tires can carry disease, so Springer noted this is where farms must target people and objects arriving onsite. Often, this category is paired with fecal/oral diseases.
  • Reproductive. “One of the best biosecurity practices to protect against reproductive diseases is to use A.I.,” described Springer. Bull studs do a great job of testing bulls before distributing semen, she said, but if you do use herd bulls, work with your veterinarian to get them tested to avoid spreading disease.

Once you have identified the risks of disease that are present on your farm, you can look for any gaps in your current procedures. Is pest control or sanitation a challenge? Is poor ventilation preventing your animals from getting fresh air? Are you incorporating new animals into the herd without a quarantine period or knowing their health history? While it’s impossible to eliminate every possible disease risk, focusing on a few key targets can make a big difference.

When developing protocols to close the procedural gaps that may be allowing disease into your farm, Springer reminded how important it is to consider who will be implementing them and how you may need to train those people. “One of the most important things when developing protocols is that the people using them know how to use them effectively,” she said.

Though biosecurity can seem like an intimidating word or a practice that can be pushed off, Springer implored farms to make it a priority. She gave an example of one farm that bought a significant number of cows when going through an expansion and unknowingly brought Mycoplasma into their herd. The costs of lost milk, milk cultures, treatments, and culling from that disease situation added up quickly, she said.

“The why behind biosecurity is to prevent these really expensive outbreaks,” Springer concluded.

To comment, email your remarks to intel@hoards.com.
(c) Hoard's Dairyman Intel 2023
August 7, 2023

Subscribe to Hoard's Dairyman Intel by clicking the button below