E Kadar

The cycle of the seminiferous epithelium in Landrace boars

The present study describes the morphological features of the eight stages of the seminiferous epithelium in Landrace boars according to the tubular morphology method, as well as their relative frequency, length, and duration. In Landrace boars the pre-meiotic stages occupied the 31.9 +/- 19.9% of the spermatogenic cycle and had a total length of 1788.8 +/- 1153.0 microm and a duration of 2.78 days; they were mainly characterised by the presence of leptotene and pachytene spermatocytes and round spermatids. Meiotic stages, with a relative frequency of 16.4 +/- 6.8%, a length of 787.1 +/- 603.1 microm and a duration of 1.41 days, contained spermatocytes in advanced meiosis I and/or in meiosis II and elongating spermatids grouped in bundles. Post-meiotic stages occupied the 50.6 +/- 20.4% of the spermatogenic cycle and had a length of 2096.8 +/- 1175.0 microm and a duration of 4.37 days; the most important event of these stages was the spermiation, which included the complete remodelling of sperm head and tail and the releasing of spermatozoa into the lumen, as well as the formation of residual bodies. From data obtained we concluded that both germ cell associations of the stages maintain constant among Landrace boars, and that the relative frequency, length and duration of the stages were directly dependent of the cytological transformations on the seminiferous tubules.

Lectin histochemistry of the boar bulbourethral glands.

The present study describes, for the first time, the glycosidic content of boar bulbourethral glands using lectin histochemistry. Fourteen horseradish peroxidase- or digoxigenin-labelled lectins with different carbohydrate specificities were used in samples obtained from 3 healthy Landrace boars. The results obtained indicate that endpiece and duct cells synthesize and secrete mainly O-glycoproteins with alpha- and beta-D-N-acetylgalactosamine, beta-D-galactose-beta(1-->3)-D-N-acetylgalactosamine, D-N-acetylglucosamine and neuraminic acid residues. Glycoproteins secreted by bulbourethral glands have a role in the protection and lubrication of the urethra. In addition, they may be also involved in the regulation of the sperm metabolic activity and in the maintenance of the structural integrity of acrosomal and plasma membranes.