Keep Vaccines Cool This Summer
"Temperature influences the efficacy of some pharmaceutials" says Maureen Hanson in a recent issue of Dairy Herd Management (May/June 2020, p 24)
It the job of the calf care persons to manage the environment for the vaccines that play an important role in preventing disease in the herd's calves.
Suggestions included in this brief review reflect the industry recommendation to keep vaccines in the temperature range of 35 and 45 F. (1.7-7.2 C).
How to do this:
1. Monitor their temperature before use - while in storage. A study in Idaho found that only 35 % of refrigerators checked on-farm stayed in the 35-45F range 95% of the time! Only a third! I would say it is time to buy a thermometer for the refrigerator if you do not already have one.
2. Keep vaccines cool while you are using them.
In practice I always used a cooler with an ice pack in the bottom when carrying vaccines in hot weather. Once on site, I only mixed one bottle at a time, gave injections, came back and mixed another bottle.
Let me share a story about a dairy that complained that their vaccines were not working (in the summer). I arrived shortly before noon on a hot summer day - it was already 90F. Two workers were ready to start giving injections. All four bottles of vaccine had been mixed and were ready to go - sitting along with the syringes on the hot tailgate of the pickup truck. No cooler, no way to keep vaccines cool from the time they came out of the refrigerator back at the utility room. Syringes were hot to the touch.
My recommendations were:
1. Change the time of day for vaccinating. I would prefer vaccinating very early morning (between 5 and 6 am) when calf body temperature is lowest. The highest calf body temperature will occur regularly around 5 pm so that is the time to be sure to avoid.
2. Put all vaccines in a cooler avoiding direct contact with ice (don't want to freeze them) and keep them there until they are ready to use.
3. Only mix as much vaccine that can be used in 15-20 minutes - especially under hot environmental conditions.
4. Keeping the syringes in a cooler will help, too.