Once a decision has been made to vaccinate against pneumonia, it’s important to have a vaccination protocol in place and available to all those responsible for vaccinating the animals. It may seem obvious advice for larger units, but even on smaller units it can’t be stressed enough how important clear written protocols are in ensuring mistakes aren’t made.
- Which List of animals that need vaccinating
- When Age of animal/time of year
- What Select the correct vaccine
- How Volume required, route of administration and interval between doses if a 2 dose course is required
The causes of pneumonia are multifactorial. Viruses such as BRSv, PI3v and IBR can act individually or in combination as primary pathogens to cause signiﬁcant lung and airway damage reducing the animal’s resistance to secondary bacterial infection. BVD virus is an important trigger for many diseases through suppression of the immune system. By protecting against these four viruses, we can clearly have a dramatic effect on protecting the respiratory health of our calves.
We’ll look at some example pneumonia vaccination protocols to show some of the considerations we take into account which help inform the decision around which vaccine and which protocol is most suitable.
Example Vaccination Protocols for Protecting Calf Respiratory Health
OPTION 1: SUITABLE FOR HOME-BRED SPRING BORN SUCKLER CALVES
Weaned and housed in autumn, these calves will be over 3 months of age at housing and ideally want protection throughout the winter months. Where no testing has been carried out, or animals are bought-in, broad cover is advisable.
Rispoval®4 may be a suitable vaccine for these animals since it provides broad cover - protecting against all 4 key BRD viruses - BRSv, Pi3v, BVDv and IBR (the BRSv and Pi3v components are live) , and protection lasts for up to 6 months, ensuring cover throughout winter housing.
As shown in the diagram, this vaccine requires two doses to be given 3-4 weeks apart with the vaccination course completed at least 2 weeks before the risk period (i.e. housing). Whilst from a management perspective it’s understandable that giving the second dose at housing may be more convenient, this means that the calves are not fully protected until 2 weeks into the housing period. In the authors experience it is not uncommon to see respiratory problems during this period. So for farmers who absolutely cannot complete the vaccination course 2 weeks prior to housing, option 2 may be more appropriate. This requires some compromise to the breadth and duration of cover so you should discuss with your vet which option is most appropriate for you individually and for your farm.
OPTION 2: SUITABLE FOR BOUGHT-IN CALVES OR AS AN ALTERNATIVE OPTION FOR SPRING/ SUMMER HOME-BRED CALVES WHERE FAST ONSET PROTECTION IS REQUIRED
For bought-in calves not vaccinated pre-sale the challenge lies in protecting them quickly enough. In these situations a 2 dose vaccine programme may not be appropriate. More rapid protection can be provided by using single dose vaccines delivered intranasally. This applies equally to home bred calves where more rapid cover is required. This speed may however come at the expense of breadth and/or duration of cover.
For example Rispoval® IntraNasal, a single dose live intranasal vaccine, will protect calves against 2 viruses, BRSv and Pi3V in just 5 to 10 days, and cover for 12 weeks. Rispoval® IBR-Marker Live is another live vaccine which can be given intranasally and will protect calves against IBR in just 7 days. The compromise is that compared to Option 1, there is no cover against BVDv, and proven cover against BRSv and Pi3v is shorter. Decisions on vaccine choice clearly involves many factors, including how they will fit into your management system. The best vaccine in the world may not be appropriate if for whatever reason you will be unable to administer it according to the label instructions.
OPTION 3: FOR AUTUMN BORN SUCKLER OR DAIRY/ DAIRY-BRED CALVES
These calves are often born into a higher risk environment so priorities are likely to be a vaccine which can be used early, works in the presence of colostral antibodies, and which works fast to provide protection and minimise pathogen loads in the shed.
Rispoval® IntraNasal, for example, is a single dose vaccine which can be used from just 9 days of age, and since delivered via the intranasal route it works in young calves, and it works in the presence of colostral antibodies, meaning it provides the earliest possible protection against 2 key BRD viruses BRSv and Pi3v.
The compromise here is that it does not include cover against BVDv and IBR, and protects for at least 12 weeks (vs 6 months for Rispoval 4). Importantly this vaccine works fast (which is arguably the highest priority in these young calves) ensuring they are protected over a critical risk period. This vaccine may be all that is required to get calves on their way, but if ongoing cover is needed follow on vaccination can be carried out as below. Again this depends on each individual farm so is a discussion to be had with your vet.
Why Do Things Go Wrong Sometimes?
Inevitably on occasion disease occurs despite use of a vaccine programme. It’s worth exploring the reasons why this could happen;
- The wrong number of doses were given: the most common problem being failure to complete a 2 dose primary vaccine course. The appeal of single dose vaccines is obvious to see.
- Incorrect inter-dose interval during a 2 dose primary vaccination course: the time interval which should be applied between the first and second doses will be stated on the product information sheet. It’s commonly between 2 and 4 weeks. If the interval is too short or too long the response to the second dose may be less than expected, potentially resulting in a reduced level of protection, or reduced duration of protection.
- Wrong age of animal: some vaccines are either not licensed for use in young animals, or are licensed but have no information on how effective the vaccine will be if the calf has colostral antibodies. Ensuring calves receive sufficient good quality colostrum is a vital part of good calf management, but those same antibodies can interfere with some vaccines.
- Wrong time: Vaccine administered too close to the risk period. This is common problem when vaccinating young stock prior to winter housing. No vaccine works immediately, they all have a period of time (known as the ‘onset of immunity’) before they provide effective protection.
- Losing track of which animals are done or which need a second injection or forgetting the booster vaccination.
- Unrealistic expectations! - Vaccination should be used as part of an overall disease control strategy, and should not be used to prop up poor management practices.
Vaccination plays a key role in protecting the health of our livestock. Vaccines are an investment in terms of cost and labour, so plan ahead and make sure that you get the most from your vaccines by storing and using them correctly.
Rispoval® RS+PI3 IntraNasal contains modified live PI3 virus, strain ts RLB103 and modified live BRSV, strain 375. For the active immunisation of MDA positive or negative calves from 9 days of age against BRSV and PI3 virus, to reduce the mean titre and duration of excretion of both viruses (POM-V).
Rispoval® 4 contains attenuated BRSV strain 375 and PI3 virus strain ts RLB103 with inactivated, adjuvanted IBR virus strain Cooper and BVDV type 1 strains 5960 (cytopathic) and 6309 (non-cytopathic). For the active immunisation of cattle to reduce infection, clinical signs and respiratory disease caused by BRSV, IBR (BHV-1) virus and PI3 virus; and leucopenia and viraemia caused by the BVDV Type 1, cytopathic and non-cytopathic strains (POM-V).
Rispoval® IBR-Marker Live contains attenuated gE negative BHV-1 strain Difivac. For the active immunisation of cattle to reduce the clinical signs of IBR, reduce virus shedding and to reduce BHV-1 associated abortions (POM-V).
Further information can be obtained from your vet or the product SPC or from Zoetis UK Ltd, First Floor, Birchwood Building, Springfield Drive, Leatherhead KT22 7LP • www.zoetis.co.uk Customer support 0845 300 8034 • CustomerSupportUK@zoetis.com • Use medicines responsibly (www.noah.co.uk/responsible) • Produced June 2019 • MM-05604.