Evaluation of the Fertilization Capability of Paracentrotus Lividus Sea Urchin Storaged Gametes by the Exposure to Different Aqueous Matrices

Abstract

Several experiments were performed to evaluate the fertilization capability of Paracentrotus lividus sea urchin gametes, which are usually used in fertilization tests, but which, until now, were employed only for few hours after spawning. The aim of this work is to evaluate the possibility of performing the bioassay for longer periods, employing 'conserved' gametes. As far as the method, the sperm was stored 'dry' at 4 degrees C; eggs were conserved in an antibiotic solution at 4 degrees C, and they were exposed both to copper solutions as reference toxicant and to aqueous matrices. The use of conserved gametes in the fertilization bioassay lead to EC50 values which were acceptable for about 3 days. Moreover, these experiments permitted to identify the limiting factor: the male gamete.

Can echinoculture be a feasible and effective activity? Analysis of fast reliable breeding conditions to promote gonadal growth and sexual maturation in Paracentrotus lividus

“…Fertilization test was performed using as reference toxicant a standard copper solution for atomic absorption analysis [Cu(NO 3 ) 2 * 3H 2 O (1000 mg/l, Fluka, Switzerland] and FSW (0.22 μm) as negative control (Lera and Pellegrini, 2006). A volume of 100 μl of sperm solution was added to each test chamber, the final solution was then maintained at 18 ± 1°C for 60 min.…”

“…After exposure to toxicant, 1 ml of oocytes suspension was added to sperm solution; after 20 min the presence of the fertilization membrane was assessed in more than 95% of the zygotes, to ensure that fertilization had occurred homogeneously within the sample. The sperm:egg ratio was fixed at 15,000:1 with approximately 1000 eggs in a final volume of 10 ml in test chambers (Lera and Pellegrini, 2006). Adult sea urchins were induced to spawn by injecting 1 ml of 0.5 M KCl solution into the coelom through the peristome.…”

Autophagy is used as a survival program in unfertilized sea urchin eggs that are destined to die by apoptosis after inactivation of MAPK1/3 (ERK2/1)

“…2,3 This period, during which fertilization triggers proper development, is less than 10 h in mammalian oocytes (around 14 h in starfish eggs, whereas sea urchin eggs can be kept for days before being fertilized). 2,4 One question that arises concerns the type of cell death that is adopted by the egg. A Nomenclature Committee on Cell Death has very recently proposed a guideline that lists the different types of cell deaths, including apoptosis, necrosis, autophagy or mitotic catastrophe.…”

Cross-border response of mosses to heavy metal atmospheric deposition in Southeastern Bulgaria and European Turkey

“…Two large glass fac- tories as well as intensively applied fertilizers in the surrounded agricultural area appear to be the plausible reason for the observed As cross-border transfer. Coşkun et al (2006) approached the distribution of the heavy metals in the soils in the Turkish part of the studied area. The content of the elements Cu, Cr, Ni, Pb and Zn correlates positively to their soil amount.…”