Estudo Cariotípico Em Duas Espécies De Cuculiformes Americanos (Aves) ()

Abstract

Two species of birds of the Cuculidae Family, Playa cayana (Phaenicophaeinae) and Crotophaga major (Crotophaginae), captured in Manaus (AM, Brazil) region have been cytogenetically studied. The chromosomes were preparared for 4 hours in culture using bone narrow cells. The karyotypic analyses were done by convencional methods from which numerical, morphological and metrical data of the chromosomes were drawn. The mean size of the macrochromosomes, the Relative Lengths (PR) and Arm Ratlos (B) were calculated on the basis of the measurements obtained. A system on decreasing order of size was used to arrange the chromosomes, designating each chromosome individually. The macrochromosomes were morphologically classified according to Levan et al. (1964). All chromosomes that had PR equal or bigger than 4% were considered as macrochromosomes. P. cayana has 2n complement of 76 chromosomes, from which 22 are considered as macrochromosomes. The Z chromosome is submetacentric and the second of the karyotype, however the W is subtelocentric and the eleventh in size. C. major has 64 chromosomes, from which 22 are macro-chromosomes. The Z chromosome is metacentric and the fourth of the karyotype, but the W chromosome is submetacentric and the sixth in size.