Bluetongue vaccine given to pregnant ewes protects lamb after birth
8 February 2010
Dr Chris Oura and colleagues at the Institute for Animal Health (IAH), an institute of BBSRC, have shown for first time that lambs born to ewes that had been vaccinated during the second year of a bluetongue (BT) vaccination programme were protected against disease after birth. The study shows protection for at least 14 weeks, which is the age at which many lambs go for slaughter. The vaccination programme uses inactivated bluetongue virus type 8 vaccine.
The protection was a result of high amounts of colostral antibody passed from ewe to offspring. This research, which was supported by Defra and done in collaboration with Professor James Wood at the University of Cambridge and the Veterinary Laboratories Agency Weybridge, is published in the journal Vaccine*.
Lower amounts of colostral antibody were transferred to lambs from ewes in the first year of a vaccination programme in which the ewes had only been vaccinated once. Although these lambs were not challenged with BT virus in the experiment, the low amounts of antibody passed to the lambs suggested that lambs born from single vaccinated sheep were likely to be protected for a shorter time than lambs born from ewes that were in the second year of a vaccination programme and had been vaccinated in both the first and the second year.
“The experiment was designed in response to wishes expressed to me by farmers,” said Dr Oura, “who wanted to know how long lambs born from vaccinated ewes were protected for. Many farmers also expressed a wish to vaccinate their ewes with inactivated BT vaccine at the same time as combined clostridial/pasteurella vaccine so they could avoid having to vaccinate their pregnant ewes on two occasions with different vaccines shortly before lambing.”
The sheep used had been first vaccinated with BTV-8 vaccine on a farm in East Anglia in May 2008. The booster BTV-8 vaccine was given at the same time as clostridial/pasteurella vaccine, in November 2008, approximately four weeks before lambing.
In a related study published in December**, Oura and colleagues showed that sheep vaccinated once with inactivated BTV-8 vaccine on a farm in East Anglia had protection for at least 10 months, more than sufficient for the UK midge season.
Bluetongue virus first came to the UK in August 2007, brought by BT virus serotype 8-infected Culicoides biting midges from the near Continent, where it had arrived in 2006. Inactivated BT virus type 8 vaccine became available in the UK from May 2008. Voluntary vaccination contributed to there being no cases of bluetongue in the UK in 2008, despite tens of thousands of cases of the disease on the Continent. There were no cases of the disease in Britain last year.
*Colostral antibody protection and interference with immunity in lambs born from sheep vaccinated with an inactivated bluetongue serotype-8 vaccine. C.A.L. Oura(a), J.L.N. Wood(b), T. Floyd(b), A.J. Sanders(a), A. Bin-Tarif(a), M. Henstock(a), L. Edwards(a), H. Simmons(c), and C.A. Batten(a). Vaccine, February 2010. doi:10.1016/j.vaccine.2010.01.028
a. Institute for Animal Health, Pirbright Laboratory, Surrey.
b. Cambridge Infectious Diseases Consortium, Department of Veterinary Medicine, University of Cambridge.
c. VLA Weybridge, New Haw, Addlestone, Surrey.
**Seroconversion, neutralising antibodies and protection in bluetongue serotype 8 vaccinated sheep. C.A.L. Oura(a), J.L.N. Wood(b), A.J. Sanders(a), A. Bin-Tarif(a), M. Henstock(a), L. Edwards(a), T. Floyd(b), H. Simmons(c), and C.A. Batten(a). Vaccine, December 2009, volume 27, 7326-7330.
About Institute for Animal Health
The Institute for Animal Health is the Bluetongue Reference Laboratory on behalf of Defra, the World Animal Health Organisation (OIE) and the EU www.pirbright.ac.uk/ref_Labs/Default.aspx?ID=1.
About Veterinary Laboratories Agency (VLA)
VLA is an Executive Agency of Defra. It is a regional network of 16 veterinary laboratories including a central facility near Weybridge in Surrey. VLA provides a wide range of applied research and consultancy on livestock diseases and surveillance of new and emerging diseases for the Government and animal health industry. It is also a national and international reference laboratory for many farm animal diseases including avian influenza, bovine tuberculosis, classical swine fever and TSEs. www.vla.gov.uk
BBSRC is the UK funding agency for research in the life sciences. Sponsored by Government, BBSRC annually invests around £450M in a wide range of research that makes a significant contribution to the quality of life in the UK and beyond and supports a number of important industrial stakeholders, including the agriculture, food, chemical, healthcare and pharmaceutical sectors.
BBSRC provides institute strategic research grants to the following:
- The Babraham Institute
- Institute for Animal Health
- Institute for Biological, Environmental and Rural Studies (Aberystwyth University)
- Institute of Food Research
- John Innes Centre
- The Genome Analysis Centre
- The Roslin Institute (University of Edinburgh)
- Rothamsted Research
The Institutes conduct long-term, mission-oriented research using specialist facilities. They have strong interactions with industry, Government departments and other end-users of their research.
Dr Dave Cavanagh, Press office, Institute for Animal Health
tel: 01635 577241
mob: 07789 941568
Matt Goode, Head of External Relations
tel: 01793 413299
fax: 01793 413382
Tracey Jewitt, Media Officer
tel: 01793 414694
fax: 01793 413382