In utero domoic acid toxicity: a fetal basis to adult disease in the California sea lion (Zalophus californianus)

California sea lions have been a repeated subject of investigation for early life toxicity, which has been documented to occur with increasing frequency from late February through mid-May in association with organochlorine (PCB and DDT) poisoning and infectious disease in the 1970's and domoic acid poisoning in the last decade. The mass early life mortality events result from the concentrated breeding grounds and synchronization of reproduction over a 28 day post partum estrus cycle and 11 month in utero phase. This physiological synchronization is triggered by a decreasing photoperiod of 11.48 h/day that occurs approximately 90 days after conception at the major California breeding grounds. The photoperiod trigger activates implantation of embryos to proceed with development for the next 242 days until birth. Embryonic diapause is a selectable trait thought to optimize timing for food utilization and male migratory patterns; yet from the toxicological perspective presented here also serves to synchronize developmental toxicity of pulsed environmental events such as domoic acid poisoning. Research studies in laboratory animals have defined age-dependent neurotoxic effects during development and windows of susceptibility to domoic acid exposure. This review will evaluate experimental domoic acid neurotoxicity in developing rodents and, aided by comparative allometric projections, will analyze potential prenatal toxicity and exposure susceptibility in the California sea lion. This analysis should provide a useful tool to forecast fetal toxicity and understand the impact of fetal toxicity on adult disease of the California sea lion.

Avaliação dos consumos de materiais estratégicos para a conservação dos engenhos de pesca artesanal de Moçambique e Estudos de constituiçāo tipologia e distribuiçāo de alguns engenhos de pesca artesanal de Moçambique

This technical report comprises two different studies in terms of their conclusions, but based on the same field surveys: “Yearly consumption evaluation of the strategic materials for the artisanal fisheries of Mozambique” and “Constitution, typology and distribution studies of the Mozambican artisanal fishing gears”. In the first of the above studies, the amount of the materials found in each gear, the number of such gears and the wear factor “r” are subject to a computed data processing, producing the following outputs: list of materials demanded in each Mozambican fishing relevant province; list of materials demanded in the whole Mozambican territory. In the second study the observed gears constitutions are analysed and differences and similitudes among them are searched. The details of maneuver and productivity are referred as well. Attention is drawn to the fact that observations did not take place on the whole Mozambican territory, even not in the most representative but in some considerably important fishing centers with reasonable safety and connection facilities. About the first study, when it was not possible to reach such considerably important centers the determination of the approximate picture of them has been achieved by verbal information of people knowing them very well and by the sources referred here in after. Concerning the second study inferences have not been made. Although a limited number of samples has been collected, the accuracy of it has been checked by inquiry. Speculations have been developed only on observed cases. The surveys have been made by a team, assigned by the directors of UD-PPE and Equipesca, under author’s coordination.