Importance of livestock vaccines explained by extension specialist
Everyone involved in livestock production has contact with vaccines.
Using them to prevent all types of disease is probably the most important management practice cattlemen can have.
Gant Maurer, Oklahoma State University Extension beef value enhancement specialist, says management techniques can offset much of the cost of preventing respiratory diseases such as shipping fever or pneumonia, which costs the U.S. cattle industry over $2 billion annually.
"A vaccine can cost over $3 a head, and if not stored properly, can be rendered ineffective," he said. "Producers cannot afford to overlook the importance of how they store vaccine and handle it prior to injection."
Biological products should be stored under refrigeration at 35 to 45 degrees F unless the nature of the product makes storing at a different temperature advisable. If vaccines are not stored within this temperature range, efficacy to the calf can be reduced, Maurer said.
Killed vaccines are especially susceptible to freezing temperatures.
"This will negatively affect the immune response to the antigen in the vaccine," he said. "Modified live viruses are more stable, but can be unactivated if they are repeatedly cycled above or below the required temperature range. Once activated, these viruses' effective life will be reduced to one to two hours and need to be maintained at the 35 to 45 degree F. Only by mixing the doses you use each time and by using a cooler can you accomplish this."
Maurer said a study conducted at the Universities of Arkansas and Idaho analyzed the consistency of temperatures for different types, ages and locations of refrigerators over a 48-period. Only 27 percent and 35 percent of refrigerators, respectively, were within the acceptable temperature limit 95 percent of the time, he said.
"Refrigerator location can also affect temperature," he said.
"Refrigerators located in barns were colder than in mud rooms and kitchens. Temperature within a 24-hour period can also be highly variable for individual refrigerators. Some can take up to eight hours to cool to the 48 degrees required or temperatures can drop below freezing and range from 29 to 45 degrees, while others will remain too cold varying from 25 to 36 degrees."
Producers need to be aware of variations in temperature so they are able to adjust refrigerator temperatures as needed. Thermostats can also be very variable from one unit to the next, so keeping a thermometer inside works well to monitor and make adjustments. Simple indoor-outdoor thermometers work well, he said. The outdoor unit can be placed in the refrigerator while the LCD display can be hung with a magnet on the door. This allows temperature to be monitored without opening the door and many models will record low temperatures for a 24-hour period so producers can adjust accordingly, he said.