Every year, farmers spend hundreds of dollars on vaccines to protect their livestock from infection and disease.
With the amount spent on vaccines, it’s worth taking a moment to reflect on how we use them, to get more ‘bang for our buck’. Avoiding easy mistakes can go a long way in getting the best results from your vaccination programme.
Read the label
This seems simple enough, but it’s often overlooked. Along with confirming the timing of administration, check that you’re using the correct dosage, route, and storage of the vaccine to reduce the risk of spoilage.
Get the timing right
Vaccination at the correct time can save you from having to use repeated doses for certain groups of animals. Optimise the timing of administration to the expected time of challenge, to ensure the vaccine generates the maximum immune response.
For example, timing of clostridial vaccination for lambs depends on the vaccination status of the ewes and how much colostrum the lambs have consumed. Orphan lambs, triplets, or lambs born to light ewes (where colostrum quality may be poorer) will often have a lower level of protection and can benefit from earlier vaccination.
Vaccines used for the prevention of abortion (i.e. Toxovax and Campyvax 4) should be administered well ahead of mating and ordered in advance.
Vaccination for Salmonella may be needed prior to the risk period for enteric Salmonella (early summer), followed by a booster dose during mid-gestation to protect against abortive Salmonella.
Store vaccines appropriately
Vaccines need to be stored chilled – not frozen or warm. But while putting them in the beer fridge in the shearing shed may seem convenient, there’s a risk they’ll freeze if the fridge is turned up to keep beer nice and cold.
At the other extreme, make sure they don’t get ‘cooked’ either. Use a chilly bin/bag to transport vaccines from where you bought them to the farm, and keep them in this while you’re out in the yards. Many vaccines are heat-sensitive and can be destroyed if left sitting in the sun or a warm vehicle.
There’s no point spending all your money and time vaccinating, only for the vaccine to be compromised and not do its job. Unfortunately, vaccines that have been frozen or excessively warmed will no longer be effective and need to be disposed of.
Prevent vaccination wounds
The location of the injection is important. Most sheep vaccines are advised to be administered in the anterior half of the neck on the top side (so close behind the back of the ear, not near the shoulder). Vaccines designed for subcutaneous use (under the skin), but injected intramuscularly can cause lesions.
Animals need to be clean and dry. Vaccinating sheep that are wet or have just been dipped is a recipe for abscesses. It creates the perfect storm: a soup of bacteria on the skin combined with a tiny injection hole. That risk is increased if you use a blunt needle.
Ensure needles are changed frequently (every 20-50 animals is recommended). Reusing old needles or ones with blunt tips, or resterilising these old blunt needles and storing them in meths, is not advised. Yes, swapping needles takes time, but it’s worth it. You will get fewer lesions if the needles are clean and sharp. The correct needle size for the job also matters.
Ensure those administering the vaccine are correctly trained to perform vaccinations to avoid unnecessary abscesses or lesions. For subcutaneous injections: slow down, tent the skin, and take the time to inject the vaccine in the correct place. This reduces the risk of injuring the animal – or getting stabbed in the finger!
If you have any questions about vaccinations for your sheep, or diseases that can be prevented by the use of vaccines, get in touch with us.
