Testicular Activity and Sperm Glycoproteins in Giant Red Shrimp (Aristaeomorpha foliacea)

By histological and histochemistry methods we found that in male Aristaeomorpha foliacea, collected from the late winter to the summer in the north-western Ionian Sea (Mediterranean Sea), the spermiogenesis and the glycoprotein pattern undergo seasonal changes and that the sperm glycoproteins mature as gametes transit from the testis to the terminal ampulla. In serial sections stained with hematoxylin and eosin the testicular activity appeared discontinuous: in late winter, testes did not show meiotic and seminiferous epithelium consisted of interkinetic spermatogonia and spermatozoa; in spring, the high spermiogenetic activity occurred and the seminiferous epithelium was mainly constituted of spermatocytes and spermatozoa; in summer, the testicular activity seemed locked again since testes containing both spermatocytes and spermatozoa were lacking. The use of twelve different lectins evidenced that the intratesticular spermatozoa from late winter to summer contain surface binding sites for SNA, MAA, Con A and KOH-sialidase (si)-WGA; in March and July they exhibited also nuclear and cytoplasmic reactivity for SNA and Con A. In the hemispermatophore the spermatozoa displayed a more complex lectin binding pattern because they also reacted with PNA, DBA, HPA,GSA II. The staining with DBA, KOH-si-DBA, and GSA II evidenced differences between the spermatozoa from late winter-spring hemispermatophore and summer hemispermatophore ones: the former showed a nuclear affinity whereas the latter displayed surface and/or cytoplasm staining. No reaction was observed with SBA, GSA I-B4, UEA I, and LTA. Introduction The giant red shrimp Aristaeomorpha foliacea (Risso, 1827), generally distributed at depths between 300-700 m, is a crustacean widewspread in the eastern and western Atlantic, Indian Ocean and western Pacific, in the waters of Japan, Australia, New Zeland and in the Mediterranean Sea (Holtius, 1980). This species plays an important role in the overall biomass of the muddy bottoms of the Mediterranean Sea and represents an important commercial resource among crustaceans since it is much appreciated by the consumer. In Aristaeomorpha foliacea, studies have been carried on the general biology, distribution and population dynamics (D’Onghia et al., 1998 for references) and, as in many crustacean species, the male reproductive tract has received little attention. Only histological observations of spermatophore formation (Tunesi,1987) and, more recently, the ultrastructural aspects of spermatozoa (Medina, 1995) have been described, whereas studies on both the testicular activity and the glycoconjugate composition of spermatozoa are lacking.