Details: Story in Agricultural Research magazine.

New Technique to Measure Leptin Activity

Chicken meat is already lean, but Agricultural Research Service scientists have made a key genetic discovery that could help produce chickens with even less fat.

Chris Ashwell of the agency’s Growth Biology Laboratory in Beltsville, Md., recently discovered a protein, called leptin, in chickens. Leptin has long been associated with obesity but until now had been found only in mammals such as pigs, cows, mice and humans. Now Ashwell and colleagues Mark Richards and John McMurtry have developed a technique to study the hormonal activity of leptin in chickens.

Maximizing meat quality and improving production efficiency are major goals for scientists studying chickens. That’s because breeding broiler chickens for growth has resulted in increased fat deposition—and reduced reproductive efficiency—in the birds.

Leptin, which regulates appetite and energy expenditure, can lead to extreme obesity, diabetes, and infertility in mammals if the leptin-producing gene is defective. Leptin is found in fat tissue of mammals and chickens, but in chickens it’s also found in the liver.

Ashwell and his team hope to use their technique to regulate the leptin levels in chickens and reduce the birds’ appetites. This would make it easier to manage broiler production and still provide consumers with quality meat. According to Ashwell, commercial industries may eventually use the technique to select birds for feeding behavior that does not affect the growth of young birds.

The technique, perfected by Richards and Ashwell, used a method called capillary electrophoresis to distinguish and measure genetic material unique to leptin. The process takes only eight minutes. The team won an award from Beckman Coulter, Inc., for achievements in capillary electrophoresis with this technique.

A story about the research appears in the May issue of ARS' Agricultural Research magazine.

Scientific contacts: Christopher M. Ashwell, Mark P. Richards, and John P. McMurtry, ARS Growth Biology Laboratory, 10300 Baltimore Ave., Bldg. 200, Room 201, Beltsville, MD 20705-2350; phone (301) 504-5061, fax (301) 504-8623, cashwell@lpsi.barc.usda.gov.