Descripción histoquímica del esófago de larvas de Merluccius hubbsi: Resultados preliminares

COHEN, STEFANÍA; DIAZ, MARINA VERA; DÍAZ, ALCIRA O.

Chascomús

Jornada; XVI Jornadas Anuales de la Sociedad Argentina de Biología; 2014

Universidad Nacional de Cuyo

The Argentinean hake, Merluccius hubbsi, is one of the most important SW Atlantic Ocean fishery resources. Several studies describe the biology of this species; however, information regarding early ontogeny is very scarce. In fish larvae, successful development of the digestive system is crucial for the survival and growth. The aim of this work was to analyze the gastrointestinal tract and its functionality during the ontogenetic development. Thus, we studied the histochemical composition and distribution of glicoconjugates (GCs) in the esophagus of hake larvae. Larvae were fixed in buffered formalin, preserved in 70% alcohol, and processed for inclusion in paraplast. Histological sections were stained with (i) PAS; (ii) AB pH 2.5; (iii) AB pH 1.0 and (iv) AB pH 0.5. Mucous cells reacted positively to the histochemical technique analyzed, indicating the presence of GCs with oxidable vicinal diols, GCs with carboxyl groups and O-sulphate esters and highly sulphated GCs. The secreted mucins could cooperate in the pre-gastric digestion, as well as in absorptive functions. Moreover, the secretion of sulphated GCs could be associated to a protective and lubricating role. This study represents the first histochemical description within hake larvae digestive system.