
Test Detects
Immune-Modifying Poultry ProteinBy Jim Core February 27, 2002A previously little-understood
protein could be used to monitor poultry health, according to studies by
Agricultural Research Service (ARS)
scientists. When chickens and turkeys become infected with different bacterial and viral
diseases, the resulting inflamation causes physiological changes, including
decreases or increases in concentrations of some serum proteins called acute
phase proteins (APPs). These amplify immune response by recruiting other cells
to the inflamation site to provide early infection resistance. APP
concentrations remain detectable in the blood until recovery, offering
potential for diagnostic or prognostic tools for poultry producers. Ovotransferrin, an iron-binding protein, is abundant in poultry blood and
eggs. Scientists at the Poultry
Production and Products Safety Research Unit in Fayetteville, Ark., found
that blood concentrations of ovotransferrin (OTF) increase in chickens with
infections. They determined that OTF is a major APP in chickens. Its
antimicrobial activities are probably related to its ability to block the
availability of iron, an essential element for bacterial growth. OTF was identified and characterized by Hang Xie, a former graduate student
working in the ARS laboratory. The researchers developed a test, called an enzyme-linked immunoassay, to
detect and measure the levels of OTF in the blood. They believe these OTF
levels can be used as an indicator of health problems in poultry, according to
Narayan Rath, a research physiologist at the Fayetteville lab. A better understanding of the roles of disease-modifying APPs in serum could
lead to new approaches for improving natural disease resistance in
poultry--such as developing genetic markers that breeders can use to select
poultry able to more effectively fight off disease. Companies have shown interest in working with the laboratory to license the
enzyme-linked test. Other potential collaborations involve developing a
diagnostic marker based on OTF to determine the health of birds during meat
inspections, either before or after slaughter. ARS is the U.S. Department of
Agricultures chief scientific research agency. Story contacts Poultry Production and Products Safety Research Narayan C Rath U.S. Department of Agriculture |