Karyological study of Gallus domesticus macrochromosomes.

After an incubation period of four days and colchicine pretreatment (air-cell method), clear metaphase figures were obtained from a cell suspension of the allantoic sacs. It was only by shortening the colchicine application to one hour that sufficiently elongated chromosomes suitable for karyological studies could be prepared. The total arm length and the arm length indices are given of the six pairs of macrochromosomes - including the Z chromosome - and of the three largest microchromosomes. Different from the previous findings as reported in the literature, the two largest macrochromosomes are described as submetacentric and not as metacentric. The findings on the seven chromosomes following agree with those given in the literature.