Change in the microchromosome number in the process of macrochromosome spiralization in Gallus domesticus

A correlation of mitotic spiralization of macrochromosomes with a change in the number of microchromosomes is detected. A wave character of microchromosomes variability during spiralization of macrochromosomes is suggested to be due to reversible despiralization of microchromosomes, which is probably a result of the colchicin treatment. Metaphase plates where the range of chromosome 1 length is from 10.5 to 12mu are recommended to calculate the number of microchromosomes.