Synaptonemal complex investigations on lamas (Lama glama) with differing fertility recordings

The present study involved three male lamas (Lama glama). Mitotic preparati ons from fibroblast culture and an electron microscopic observation on the synaptonemal complexes (Scs) were reported. Special attention was given to the morphology and behaviour of the chromosomes at the zygotene and pachyte ne substages of prophase I in primary spermatocytes from lamas. Analysis of mitotic preparations show diploid and triploid cells, with a relatively hi gh frequency of polyploidy. Analyses of synaptonemal complexes in primary s permatocytes were carried out, on 89 cells. Pairing abnormalities were only recorded in an average of 63% of the cells of the animal Tabasco. The othe r two animals were normal. The photographed cells give an upper limit estim ate of the existing abnormalities, as there was a deliberate tendency towar ds selecting abnormal cells for photography. The presence of degenerating p rimary spermatocytes in SC preparations as well as in testicular sections, and the absence of spermatozoa in ejaculates confirm the chromosomally deri ved male sterility of one animal.