The karyotype of the Gallus gallus × Phasianus colchicus mongolicus hybrid was studied in mitoses obtained from peripheral blood leucocytes cultures. The culture method provided high numbers of well spread metaphase chromosomes, without overlapping and suitable for chromosome counts. The modal diploid number of chromosomes found was 78, the same as in the chicken. The hybrid constitution was confirmed by the presence of a macrochromosomal set derived from each parental species, the chicken and the pheasant. In particular, the hybrid origin of metaphases was easily determined by the morphology of two pairs of homologous chromosomes, numbers 2 and 4. The nucleolar organiser regions (NOR) encoding the 18S–5.8S–28S ribosomal DNA, were detected by the silver nitrate staining in one pair of chromosomes, as in the chicken.
BasrurP.K. and YamashiroS. (1972) Chromosomes of chicken–pheasant hybrids. Genet. Sel. Evol., 4, 495–503.
2.
BenirschkeK., BrownhillL.E. and BeathM.M. (1962) Somatic chromosomes of the horse, the donkey and their hybrids, the mule and the hinny. J. Reprod. Fertil., 4, 319–326.
3.
BurtD.W. (2003). Comparative genomics. In: MuirW.M. and AggreyS.E. (eds.), Poultry genetics, breeding and biotechnology, pp. 563–606. CAB International.
4.
CastilloA., MarzoniM., RomboliI. and StanyonR. (2007) Sex determination in Gallus gallus × Phasianus colchicus. Avian Poultry Biol. Rev., 18, 57–58.
5.
ChavesL.D., KruethS.B. and ReedK.M. (2007) Characterization of the turkey MHC chromosome through genetic and physical mapping. Cytogenet. Genome Res., 117, 213–220.
6.
CutlerD.W. (1918) On the sterility of hybrids between the pheasant and the Gold Campine. J. Genet., 7, 155–165.
7.
GarneroA.D.V. (1996) Citogenética de Tinámidos de la Provincia de Misiones. Licenciature thesis, UNaM, Posadas Mnes.
8.
GriffinD.K., RobertsonL.B.W., TempestH.G. and SkinnerB.M. (2007) The evolution of the avian genome as revealed by comparative molecular cytogenetics. Cytogenet. Genome Res., 117, 64–77.
9.
GunskiR.J., BlancoP.V., Riviello LopezG. and El HakehJ.L. (1995) Estudios de las regiones organizadoras del nucléolo en palomas (Aves: Columbidae). Paper presented at XXVI Cong. Arg. de Genética Abstr., San Carlos de Bariloche, 17.
10.
GunskiR.J. and GiannoniM.L. (1998) Nucleolar organizer regions and a new chromosome number for Rhea americana (Aves: Rheiformes). Genet. Mol. Biol., 21, 207–210.
11.
HowellW.M. and BlackD.A. (1980) Controlled silver-staining of nucleolus organizer regions with a protective colloidal developer: a 1-step method. Experientia, 15, 1014–1015.
12.
Ladjali-MohammediK., BitgoodJ.J., Tixier-BoichardM. and Ponce De LeonF.A. (1999) International System for Standardized Avian Karyotypes (ISSAK): standardized banded karyotypes of the domestic fowl (Gallus domesticus). Cytogenet. Cell Genet., 86, 271–276.
13.
LoyezM. (1906) Recherches sur le development ovafien des oeufs meroblastiques a vitellus nutrif abondant. Arch. Anat. Micros., 8, 239–397.
14.
MasabandaJ.S., BurtD.W., O'BrienP.C.M., VignalA., FillonV., WalshP.S., CoxH., TempestH.G., SmithJ., HabermannF., SchmidM., MatsudaY., Ferguson-SmithM.A., CrooijmansR.P.M.A., GroenenM.A.M. and GriffinD.K. (2004) Molecular Cytogenetic Definition of the Chicken Genome: The First Complete Avian Karyotype. Genetics, 166, 1367–1373.
15.
NishidaC. and SasakiM. (1980) A preliminary note on the nucleolus organizing regions of metaphase chromosomes in five species of cranes (Aves: Gruiformes). Chromosoma, 28, 12–14.
16.
OgumaK. (1938) Studies on sauropsid chromosomes. V. The karyotypes of the quail and the duck, different from those reported by previous authors. Ann. Zool. Jpn., 17, 612–622.
17.
RasbandW. (2005) ImageJ. National Institute of Mental Health, Bethesda, Maryland, USA.
18.
RochaG.T. and LuccaE.J. (1988) Nucleolar organizer regions in somatic chromosomes of some species of birds. Caryologia, 41, 299–308.
19.
RyttmanH. and TegelstromH. (1983) Chromosomal evolution in the family Phasianidae (Aves). Hereditas, 98, 71–75.
20.
SchmidM., NandaI. and BurtD.W. (2005) Second report on chicken genes and chromosomes 2005. Cytogenet. Genome Res., 109, 415–479.
21.
SeabrightM. (1971) A rapid banding technique for human chromosomes. Lancet, 2, 971–972.
22.
ShibusawaM., NishiboriM., Nishida-UmeharaC., TsudzukiM., MasabandaJ., GriffinD.K. and MatsudaY. (2004) Karyotypic evolution in the Galliformes: An examination of the process of karyotypic evolution by comparison of the molecular cytogenetic findings with the molecular phylogeny. Cytogenet. Genome Res., 106, 111–119.
23.
StockA.D. and BunchT.D. (1982) The evolutionary implications of chromosome banding pattern homologies in the bird order Galliformes. Cytogenet. Genome Res., 34, 136–148.
24.
SusukiK. (1930) On the chromosomes of the domestic fowl. Zool. Mag., 42, 358.
25.
YamashinaM.Y. (1943) Studies on sterility in hybrid birds: Cytological researches on hybrids in the family Phasianidae. J. Fac. Sci. Hokkaido Imp. Univ., VI. Zoology, 307–386.
