Scientists pave the way for vaccine to combat devastating avian disease

(Press-News.org) Recent reduction in the use of antibiotic growth promoters in animal feeds has resulted in a dramatic increase in the severe poultry disease - necrotic enteritis. New research suggests that the disease, which is costing the worldwide poultry industry an estimated £600 million a year, could be prevented by immunisation with a vaccine that is being developed at the University of Exeter.

Professor Richard Titball of the University of Exeter said: "Necrotic enteritis is a major concern for the poultry farming industry worldwide and poultry producers are waiting for this desperately needed vaccine. Our work will pave the way for the development of a vaccine that will help farmers tackle this devastating disease."

In recent years concern over the impact of antibiotics in the food chain has led to an EU-wide ban in the use of antimicrobial growth promoters in animal feeds and a general reduction in use word-wide. These antibiotics, added to promote the growth of poultry, also prevented necrotic enteritis and other diseases.

Necrotic enteritis, which causes lesions in the intestines of poultry resulting in severe illness and even death, is caused by the bacterium Clostridium perfringens. Research has shown that the bacterium produces a toxin called NetB and much of the disease is caused by the effects of this toxin. Researchers at the University of Exeter, in collaboration with Ghent University, Belgium and Birkbeck College, University of London, have unravelled the molecular structure of the NetB toxin. Exchanging crucial amino acids in the NetB toxin, using molecular biology techniques, has enabled the researchers to identify a non-toxic form of NetB.

The researchers have discovered that immunisation with non-toxic NetB results in protection against necrotic enteritis. This research has just been published in the Journal of Biological Chemistry and in Vaccine.

Sergio Fernandes da Costa, from the University of Exeter, said: "This is a tremendous step towards developing a necrotic enteritis vaccine that will control this disease in the future. We are working closely with the animal health industry to develop a product that can be efficiently given to entire poultry flocks in feed or water."

### This research was supported in part by the Wellcome Trust and in part by the European Union Marie Curie Network.

About the University of Exeter The Sunday Times University of the Year 2012-13, the University of Exeter is a Russell Group university and in the top one percent of institutions globally. It combines world-class research with very high levels of student satisfaction. Exeter has over 18,000 students and is ranked 7th in The Sunday Times University Guide, 10th in the UK in The Times Good University Guide 2012 and 10th in the Guardian University Guide. In the 2008 Research Assessment Exercise (RAE) 90% of the University's research was rated as being at internationally recognised levels and 16 of its 31 subjects are ranked in the top 10, with 27 subjects ranked in the top 20.

The University has invested strategically to deliver more than £350 million worth of new facilities across its campuses for 2012, including landmark new student services centres - the Forum in Exeter and The Exchange in Cornwall - and world-class new facilities for Biosciences, the Business School and the Environment and Sustainability Institute.
http://www.exeter.ac.uk

For further information: Dr Jo Bowler
University of Exeter Press Office
+44 (0)1392 722062
pressoffice@exeter.ac.uk

About Birkbeck Birkbeck was founded in 1823 by Dr George Birkbeck, who started a revolution in London's education system by establishing a college specifically for working people. Part of the University of London, Birkbeck is London's only specialist provider of evening higher education, making the very best university education accessible to non-traditional students. Over 18,000 students from diverse social and educational backgrounds participate in a broad range of higher education opportunities at Birkbeck.

Birkbeck ranks among the top 1% research-intensive universities in the world, according to the 2012 Times Higher Education World University Rankings. With over 90 per cent of academics research-active, the College is a vibrant centre of academic engagement and excellence. The College has consistently ranked number one in the National Student Survey, and this year topped the poll for student satisfaction and teaching in London.

For further information: Bryony Merritt
Birkbeck Press Office, University of London
+44 (0)20 7380 3133
b.merritt@bbk.ac.uk

About Ghent University Since being founded in 1817, Ghent University has steadily established itself as one of Belgium's leading research universities. Ghent University offers a broad range of programmes in academic and scientific branches, with high-quality research-based educational programmes in virtually every scientific discipline. The appeal of Ghent University as an institute of higher education is growing every year, with a total number of 36.000 students in 2013.

Numerous research groups, centres and institutes have been founded over the years, becoming world-renowned in various scientific disciplines, such as biotechnology, aquaculture and micro-electronics.
http://www.UGent.be

For further information: Ms Stephanie Lenoir
Ghent University Press Office
+32 9 264 82 76
Stephanie.Lenoir@UGent.be

About the Wellcome Trust The Wellcome Trust is a global charitable foundation dedicated to achieving extraordinary improvements in human and animal health. It supports the brightest minds in biomedical research and the medical humanities. The Trust's breadth of support includes public engagement, education and the application of research to improve health. It is independent of both political and commercial interests.
http://www.wellcome.ac.uk