The unimmunological yellow-maroon-feather quails and their hybrids respectively at the age of 3, 5, 10, 15, 20, 30, 40, 50, 70 days were inoculated with new castle disease virus (F48E9).

• 摘要用鸡新城疫强毒F48E9分别对3,5,10,15,20,30,40,50和70日龄的未免疫鹌鹑进行攻毒。