5 September 1997

Vaccination before housing can cut calf pneumonia trouble

By Emma Penny

CATTLE producers should consider pre-housing vaccination program-mes to reduce calf pneumonia now.

Where respiratory syncytial virus has been the cause of past pneumonia concerns – diagnosed by post-mortem or blood tests – producers should ensure calves are fully vaccinated about two weeks before calving. That means giving the first dose of RSV vaccine now, warns Mark Crawshaw, veterinary investigation officer at SAC Auchincruive, Ayr.

"Animals four months or older require two doses of vaccine, given three weeks apart. To ensure good immunity, calves should receive the second dose of RSV vaccine about two weeks before housing. If calves are housed too soon after the second injection, protection will be less effective."

Calves which are younger than four months old at housing may still have some antibodies from their mother, which can interfere with vaccination. The farm vet should be consulted before these calves are treated, says Mr Crawshaw.

"Try to avoid other stresses at the time of vaccinating as this will reduce their effectiveness. Calves should not, therefore, be vaccinated and weaned at the same time."

Vaccines for RSV come in five dose phials, and the dose rate is the same for all calves over four months old, he says. "In theory, you should use a new needle for every calf. Where this is not done, needles should be changed at least after every five animals."

He suggests producers keep one sterile needle in the phial, which remains in the phial for withdrawing vaccine, and is not used for injecting calves. "This will prevent vaccine contamination."

But Mr Crawshaw warns that the causes of pneumonia are complex, and that any planned vaccination programme should be discusses with the farm vet first. &#42