Questions have been raised about the numbers of vaccinations given to pullets in their first 16 weeks of life.

Addressing a recent meeting of the Severn Valley poultry discussion group, Helen Houghton of vaccine supplier Merial Animal Health explained that, depending on the exact programme, birds might be getting between 20 and 25 doses during that period.

This included occasions when more than one vaccine is given at the same time, and repeat or booster doses.

But Charles Macleod, general manager of pullet rearing at Humphrey Pullets, questioned whether it was absolutely vital that all these vaccines were used.

“Vaccine programmes are getting more and more complicated, the birds are getting more vaccines into them, so is there scope to improve the environment the birds are kept in, to be able to simplify some of the vaccine programmes?” he asked.

Mrs Houghton said that vaccination programmes were essentially a form of insurance, and cutting back should only be attempted on a trial basis under the most favourable situations

“If your site is clean and you don’t have any chicken farms around you, and there is very little infectious pressure, you could probably try to drop some vaccines and see what happens,” she said.

“But you do need to make sure your biosecurity is spot on. That’s not just for your farm staff, but also for visitors. I’ve turned up on farms where the engineer whistle stops up there. He’s in and he’s gone, hasn’t changed into anything, done no foot dips, and you’ve no idea where he’s come from.”

One producer at the meeting wanted to know whether any vaccines should be given on farm after 16 weeks.

Mrs Houghton said it was certainly possible to give IB vaccines in the field. “But I’m a great believer in making sure your first 16 weeks’ worth of vaccines is absolutely spot on, and making sure you’ve got a good antibody response in the birds by testing at, say, 22 weeks.

“However, if you’ve had a lot of challenges to IB, that’s when you need to get it diagnosed. Vets will look at individual cases and, if you’re shown to have a problem in one flock, you might be advised to spray the next flock with IB vaccine. But if you’ve never had a problem, I wouldn’t start with it.”

For more on vaccination techniques, check out May’s Poultry World