Scientists Grapple With New Virus Threat to Broiler Industry

A new virus strain has reached epidemic proportions in broiler breeder chickens around the world in the past two years. Avian leukosis is a group of viruses that cause tumors in chickens, eventually killing them.

The same Agricultural Research Service lab that helped eradicate earlier forms of the virus is attacking the newest strain, known as avian leukosis subgroup J (ALV-J).

Like earlier strains of avian leukosis, subgroup J poses no threat to humans or other animals. But, as the most virulent avian leukosis strain to date, it is a major threat to the industry's economics. Shortages of breeding stock are already showing up. That causes concern in the U.S. industry, which currently meets a U.S. market demand for almost 8 billion broilers a year.

At the ARS Avian Disease and Oncology Laboratory in East Lansing, Mich., Aly M. Fadly, an ARS veterinary medical officer, heads the ALV-J research team. He and colleagues are developing viral detection kits for industry. They're also testing potential vaccines.

They have developed a DNA-based lab test for detecting the virus. But they want to develop a field kit for breeder farms. They developed the test through a cooperative research and development agreement with a major breeding company. They expect more such R&D agreements on diagnostic test kits as well as potential vaccines.

The East Lansing researchers are testing key ALV-J proteins for use in diagnostic kits and vaccines. One protein has been supplied to several companies, one of which is testing the potential of the protein for use in diagnosis.

A story about the fight against the new avian leukosis epidemic appears in the August issue of ARS' Agricultural Research magazine. The article also is on the World Wide Web at:

http://www.ars.usda.gov/is/AR/archive/aug98/viru0898.htm

Scientific contact: Aly M. Fadly, ARS Avian Disease and Oncology Laboratory, East Lansing, Mich., phone (517) 337-6837, fax (517) 337-6776, fadly@pilot.msu.edu.