Hunt launched for red mite vaccine
Scientists have launched a project to develop a vaccine against red mite. If successful it means one jab could wipe out one of the biggest problems facing the free range industry. The research is based at Newcastle University’s School of Agriculture and forms a wider project examining the extent of the red mite menace. An initial survey among egg producers in the North East has shown that 87% of farms have mite infestations and that free range units are hardest hit.
The three year project is being led by Dr Jonathan Guy and follows the development of vaccination programmes to counter the effects of ticks in tropical climates. Two commercial vaccines are now available to protect stock against ticks.
The idea is to use the mite itself, perhaps its mouth parts or digestive juices, to produce an antigen and then develop this into a vaccine. When a mite began to feed on a vaccinated hen it would in effect kill itself.
Funding worth £70,000 has already been forthcoming for the project and producers in the North of England are offering support. But the research team is now searching for assistance to complete a £100,000 funding package. Talks have already begun within BFREPA with a view to backing the project.
In the first results to emerge from the red mite research—published in the journal British Poultry Science—the Newcastle team found that mite populations were “significantly higher” in free range units than in cage or barn units.
The study, which involved 29 farms and over a million hens, was based on placing traps in buildings for seven days. They revealed that while numbers of nymph and adult mites collected in barn and cage units was less than a thousand, on free range farms the totals topped 2,500.
Over 80 per cent of producers used acaricide treatments while the birds were in the buildings and 67 per cent treated again when the birds were cleared. The use of other control techniques was far less common. Only one in five said they had designed new buildings with a view to minimising harbourages and only 17 per cent had used sealant on joints in sheds. Just 21 per cent cleaned the outside of the building as recommended by Defra. But one fascinating finding was that 13% of farms reported no red mite problem. Why?
“As yet we do not know the answer to that question,” said Dr Guy. “Clearly analysing what factors they have in common is important and that will be done. It could simply be that that they are absolutely vigilant in their approach to monitoring and treating.
“We also have no clear reasons why free range units should have shown higher levels of mite presence. They do of course generally have more places to accommodate mite in terms of wooden construction of buildings, perches and nest boxes. And of course there is always the presence of wild birds which can bring mite into a flock.
“But these are areas we want to explore further. Our research will have two main focuses. Discovering why some farms have more severe problems than others and developing the vaccination approach.”
