title: Tissue parameters of the sea urchin (Paracentrotus lividus): the effects of magnesium and transport stress.
abstract: The present study investigates some biochemical and biological variables in sea urchins (Paracentrotus lividus) that were stressed in the course of collection, transportation and laboratory conditioning and the effect thereon of pre-treatment with a test compound; magnesium chloride (MgC12). Handling and transportation for 5h resulted in significantly decreased gonadal indices due to unplanned spawning. The pre-treatment of sea urchins with 5 mmol 1(-1) MgCl2 reduced unplanned spawning during all of the experiments. Protein content and humidity were significantly higher (p < 0.05) in sea urchins treated with Mg than in the control group, these differences between groups were maintained throughout the experimental period. The analyses of gonad mineral compounds (Na+, K=, P, Ca2+ and Mg2+) showed a significantly higher (p < 0.05) Na+ and K+ tissue contents in the Mg-treated group than the control group throughout the conditioning period. Phosphorus with initial similar levels in both groups, however, showed a significantly higher gonad level (p < 0.05) in the Mg-treated group towards the end of the experiment (> 9 days).
authors.affiliation: Institut National des Sciences et Technologies de la Mer, 28 Rue 2 Mars 1934, Carthage, Salammbo 2025, Tunisia.
authors.forename: Soumaya
authors.initials: S
authors.lastname: Arafa
authors.forename: Saloua
authors.initials: S
authors.lastname: Sadok
authors.forename: Amor
authors.initials: A
authors.lastname: El Abed
mesh_terms: D000596:Amino Acids / Q000032:analysis*; D000818:Animals; D048429:Cell Size; D005854:Germ Cells / Q000166:cytology* / Q000378:metabolism; D006066:Gonads / Q000737:chemistry; D006813:Humidity; D015636:Magnesium Chloride / Q000494:pharmacology*; D009929:Organ Size; D012617:Sea Urchins / Q000378:metabolism*; D013312:Stress, Physiological; D014018:Tissue Distribution; D014186:Transportation
chemical_list: D000596:Amino Acids; D015636:Magnesium Chloride