Age-dependent change in the morphology of nucleoli and methylation of genes of the Nucleolar Organizer Region in Japanese quail Coturnix japonica) model (Temminck and Schlegel, 1849) (Galliformes: Aves).

Nucleoli are the product of the activity of nucleolar organizer regions (NOR) in certain chromosomes. Their main functions are the formation of ribosomal subunits from ribosomal protein molecules and the transcription of genes encoding rRNA. The aim of the study was to determine the shape of nucleoli and analyse methylation in the gene RN28S in the spermatocytes of male Japanese quail (Coturnixjaponica) in two age groups.

The effect of environmental factors on sister chromatid exchange incidence in domestic horse (Equus caballus) chromosomes.

The SCE test is often used as a sensitive and reliable technique in the biomonitoring of genotoxicity of mutagenic and carcinogenic agents. This study analysed the frequency of sister chromatid exchange in domestic horse chromosomes depending on the habitat and age of the analysed horses. The chromosome preparations were obtained from an in vitro culture of peripheral blood lymphocytes stained using the FPG technique.

Sister chromatid exchange in Polish White improved goats (Capra hircus).

The study was aimed at evaluating the frequency of spontaneous sister chromatid exchange in Polish White Improved goats (Capra hircus). The mean number of SCEs/cell was 2.73 +/- 1.

Number and size of nucleoli in the spermatocytes of chicken and Japanese quail.

Nucleoli are the product of nucleolus organizing region activity (NOR) of specific chromosomes. Their basic function is to synthetise ribosomal RNA precursors and promote the maturation and assemblage of preribosomal RNP molecules. Information on rRNA-coding gene activity can be provided by the analysis of the number and size of nucleoli in the prophase of the first meiotic division.

Structure of the nucleoli in domestic cattle spermatocytes.

The work was aimed at determining the number and morphology of nucleoli in the prophase of the first meiotic division in domestic cattle males. The use of AgNO₃ staining, commonly applied in cytogenetics for the identification of nucleolar organiser regions, made it possible to identify nucleoli in first-order spermatocytes. One nucleolus was identified in each analysed cell.

Comparing the karyotype of the European domestic goose and the Asian goose on the basis of the karyotype of their interspecific cross-breed, using the RBG chromosome staining technique.

The aim of the research was to compare the karyotypes of two goose species: the European domestic goose and the Asian goose on the basis of the karyotype of their interspecific cross-breed, using the RBG chromosome staining technique. The karyotype standard for Anseriformes has not been determined yet. The RBG technique is considered as one of the standard methods for analysing chromosomes.

Identification and structure of lampbrush sex bivalents prior to and after the reproductive period of the European domestic goose Anser anser.

Lampbrush chromosomes (LBCs) present in bird oocytes are a new model in cytogenetics with particular significance for bird chromosome analysis. The fact that female birds are heterogametic makes it possible to observe both sex chromosomes in the form of decondensed structures typical of lampbrush chromosomes. A change in transcription activity associated with physiological processes in geese prior to and after the reproductive season is reflected in chromosome morphology.

Description of the Muscovy duck (Cairina moschata) karyotype.

The karyotype of the Muscovy duck originating from Cairina moschata was characterised on the basis of R and C bands. Chromosomal preparations obtained from an in vitro blood lymphocyte culture were RBG- and CBG-stained. The structures of nine and fourteen pairs of chromosomes were examined based on R bands and C bands, respectively.

The structure of the synaptonemal complexes in meiocytes of European domestic goose (Anser anser).

The synaptonemal complex (SC) is a protein structure which binds two homologues during prophase of the first meiotic division and assures the correct course of genetic recombination. The demonstration and identification of SCs in European domestic goose Anser anser was the aim of the current research. Standard techniques of SC identification do not allow for an analysis of their molecular structure.

Description of the Anser cygnoides goose karyotype.

The karyotype of the domestic goose A. cygnoides was characterised on the basis of R and C bands. Chromosomal preparations obtained from an in vitro culture of blood lymphocytes were stained by means of the RBG and CBG banding techniques.

Description of the mallard duck (Anas platyrhynchos) karyotype.

The karyotype of the mallard duck, Anas platyrhynchos, was characterised on the basis of R and C bands. Chromosomal preparations obtained from in vitro blood lymphocyte cultures were RBG- and CBG-stained. The structures of nine and 14 pairs of chromosomes were analysed by the RBG and CBG chromosome banding techniques, respectively.

Description of the Anser anser goose karyotype.

The karyotype of the Italian goose originating from Anser anser was characterised on the basis of R and C bands. Chromosomal preparations obtained from an in vitro culture of blood lymphocytes were stained with the RBG and CBG techniques. The RBG technique enabled the analysis of the structure of nine pairs of chromosomes whereas the CBG technique - fourteen pairs ofchromosomes from the total ofeighty goose chromosomes.