Research performed by the University of Nottingham and DairyCo highlight areas which can be improved to make vaccines work more effectively. Louise Hartley gets the top tips from Dutch vet Wendela Wapenaar.
Vaccines help to reduce the incidence or the severity of disease by stimulating the immune system to provide protection.
Dr Wendela Wapenaar, based at Nottingham University, has been part of a study project with DairyCo to improve vaccination strategies on farm.
She highlights five important areas to focus on in order to get the most from vaccines.
Store and use the vaccine at the correct temperature, from the moment you pick it up until the moment you use it
Avoiding sunlight exposure and keeping the vaccine at the correct temperature is particularly important, says Dr Wapenaar.
She says: “Most vaccines should be stored between 2-8degC. However, some need to be warmed to room temperature before use. Never use hot water or a microwave to warm them up. Storage of vaccines at the wrong temperature is a very common reason for vaccine failure, and this applies from the time you pick up the vaccine until it is injected.
“Vaccine bottles can only be kept for a short time once they have been opened and it is important to check the datasheet for the storage requirements.
“Freezing is detrimental for most vaccines, therefore a ‘max-min thermometer’ - which indicates the highest and lowest temperature in your fridge - is a great investment to ensure adequate storage.
“They only cost about £10 and may save you from losing a lot of money in the long-term.”
Use the vaccine at the correct time, interval, dose and route
Vaccines change, even though their name may not. It is therefore important to read the vaccine’s insert and familiarise yourself with the product even if you have used it several times before, Dr Wapenaar says.
She says: “Vaccines are most effective when used on healthy animals. Stock to be vaccinated should not be suffering from any disease or other type of stress.
“It is not advisable to vaccinate ill animals as their immune status is likely to be compromised, resulting in little or no response to the vaccine and, as such, they will not be adequately protected against disease.”
Always administer the full course of vaccine at the recommended dose and time. To maintain protection, the second dose in a primary course must be given at the correct time interval - this usually varies between two and six weeks.
Certain vaccines need to be prepared by mixing a powder or freeze-dried pellet with a solution. The powder or pellet contains the actual vaccine and it is important to only mix it with the solution provided. Once the vaccine is made up it will only be effective for a short period of time, usually a matter of hours, says Dr Wapenaar.
“Most vaccines have limited information on whether they can be used simultaneously with another vaccine.
“A decision on using vaccines on the same day can be made in discussion with your vet.
“Unless specifically stated on the datasheet, on no account should different vaccines or treatments, be mixed together.”
Ensure good hygiene when using the vaccine and equipment
The middle of the neck is the preferred vaccination site, for any injection, be it vaccines, antibiotics or de-wormers.
Avoid the hind quarters, hip or thigh - regardless of age or purpose of cattle - as the vaccination can damage muscle at the injection site.
Dr Wapenaar says: “Up to 6 per cent of cattle carcases contain abscesses and injecting stock with dirty needles or a poor injection technique are both common causes for this.
“Abscesses have to be cut out of the carcase, which reduces meat yield and potentially devalues the carcase.”
Avoid injecting animals which are wet or dirty as this increases the risk of contaminating the injection site, she says.
“Disinfecting the skin - as performed when vaccinating people - tends not to be done in cattle as their coat makes it difficult to disinfect the area effectively. However, when the correct technique is used, complications seldom occur.”
It is important to change the needle regularly, as using dirty needles increases the chance of an abscess around the injection site. It is also possible to transmit diseases between cattle via the needle.
Dr Wapenaar says: “This risk is avoided by using a new needle for every animal or changing needles between different groups of animals on the farm.
“A needle only costs about 10p and should be replaced when it gets bent or blunt.”
Ensure adequate safety for people and animals
Dr Wapenaar says it is vital to make sure handling facilities are safe for both operator and animal, advises Dr Wapenaar.
She says: “Take care when injecting animals as vaccines can cause serious injection site reactions if you accidentally inject yourself. If self-injections happen, seek medical help from your GP.
“Using vaccinating guns with a protective cap can help prevent injury.”
Ensure accurate recording of vaccinations is carried out
Record the vaccine which has been used and the date of injection for all vaccinated animals in your herd health plan and medicine book.
Keeping these records for five years is a legal requirement and is requested by many farm assurance schemes.
Dr Wapenaar says: “It is recommended to make your vet aware of recent vaccinations when TB testing, as both are applied in the same area of the neck.
“If possible, choose and record one side of the neck for TB testing and use the other side for vaccination.
“This will make it less likely to confuse a possible vaccination reaction lump for a TB reaction.”