Cryopreservation of avian spermatozoa.

This chapter describes a simple system for cryopreservation of avian spermatozoa as pellets, formed by dropping volumes of sperm suspension directly into liquid nitrogen with dimethylacetamide as cryoprotectant. The method originates from the group at the Research Institute of Farm Animal Breeding and Genetics at St. Petersburg-Pushkin and is described here for chicken spermatozoa, but has also been adapted successfully for other species, such as Houbara bustards and pheasants.

Species specificity in avian sperm:perivitelline interaction.

The interaction of chicken spermatozoa with the inner perivitelline layer from different avian species in vitro during a 5 min co-incubation was measured as the number of points of hydrolysis produced per unit area of inner perivitelline layer. The average degree of interaction, as a proportion of that between chicken spermatozoa and their homologous inner perivitelline layer, was: equal to or greater than 100% within Galliformes (chicken, turkey, quail, pheasant, peafowl and guineafowl); 44% within Anseriformes (goose, duck); and less than 30% in Passeriformes (Zebra Finch) and Columbiformes (collared-dove). The homologue of the putative chicken sperm-binding proteins, chicken ZP1 and ZP3, were identified by Western blotting with anti-chicken ZP1/ZP3 antibody in the perivitelline layers of all species.

Excess nuclear DNA in spermatozoa of guinea fowl.

The proportion of spermatozoa with elongated nuclei in ejaculates from a strain of guinea fowl was estimated, subjectively, to range from approximately 1 to 6%. It was confirmed by image analysis that in an ejaculate from one male, the distribution of nuclear lengths was bimodal, with a distinct population comprising 10% of spermatozoa having a mean nuclear length that was 52% greater than that of the remaining 90%. Furthermore, the mean DNA content of the 'large-nuclei' population was 1.