2.1 │ Sample origin
The positive rates of virus isolation and p27 antigen in breeding eggs
of an indigenous chicken were both within 1% for two consecutive
generations. In order to introduce new genes, the introduction of
Hy-line brown fast feathering roosters and artificial insemination were
performed. Ever since, about 7.61% (7 from 92 samples) were found to be
p27 positive in the albumen samples. Therefore, semen and plasma samples
from the same males (46 samples), plasmas from hens (92 samples) and
albumens from the five ALV positive hens (10 samples) were collected for
virus isolation of for ALV, respectively.