October 31, 2017 by Jan Suszkiw
A new test developed by Agricultural Research Service (ARS) scientists in College Station, Texas, could make it easier to breed pathogen-resistant chickens.
The test identifies roosters whose blood contains naturally high levels of two key chemicals, cytokines and chemokines. These chemicals mobilize the birds' innate immune response, according to ARS microbiologist Christi Swaggerty, in ARS's Food and Feed Safety Research Unit.
Using the new test, commercial poultry breeders can single out roosters that have a strong immune response and use them to selectively breed a more robust flock. Such resistance, especially during the birds' first week of life, may lower costs related to animal well-being and food safety.
Protecting chickens from pathogens involves sanitation, vaccination, biosecurity and use of antibiotics and other medications. But some chickens have an especially robust and efficient immune response and can resist pathogens, notes Swaggerty.
The researchers used the test to select roosters for breeding a line of resistant broilers. They then exposed the resistant broilers to several pathogens. They compared the resistant group to a group of susceptible broilers bred from roosters with low cytokine and chemokine levels.