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This research represents the first result of studies of the common snook Centropomus undecimalis larvae from broodstock matured in captivity in Brazil. The aim of this study was to evaluate if the inclusion of Acartia tonsa nauplii improves stress resistance of common snook larvae. The larvae were fed with: rotifers Brachionus plicatilis (10 to 15 mL-1); A. tonsa nauplii (0.25 to 0.5 mL-1) and rotifers (5 to 7.5 mL-1), and A. tonsa nauplii (0.12 to 0.25 mL-1). The average percentage of survival of the treatments was 11.9%. At 20 days of age, larvae were subjected to thermal stress. Subsequently, the stress resistance was evaluated. Common snook larvae fed B. plicatilis+A. tonsa reached a higher weight and length (7.5 ± 0.00 mg and 9.1 ± 0.23 mm, respectively) and resisted more heat stress (87.4%) than larvae fed other foods, indicating that the feed mixture is satisfactory as a starter diet for larvae of common snook. However, more research is needed to confirm these results.

This study aims to assess the distribution patterns of porcellanid crabs in the intertidal zone of Sepetiba Bay, Rio de Janeiro, Brazil, identifying the abiotic determinants. Samples were collected seasonally (dry and rainy seasons) from January 2005 to August 2007, during low tides in external, intermediate and internal sectors. The crabs were hand caught in consolidated substrates with sampling effort of two people in three different flood zones (lower, medium and higher) for 30 min. Water temperature, salinity, accumulated rainfall, the physical and chemical variables of sediment were analyzed concerning interaction in the distribution patterns of the species. A total of 3,389 crabs, belonging to five genera and eight species, were obtained. With the exception of Petrolisthes armatus, found throughout the intertidal range, all species inhabited the intertidal bottom of Sepetiba Bay exclusively. Favorable environmental conditions of the Sepetiba Bay enabled the success of colonization of several porcellanid species which are a refuge and feeding environment of the Marambaia Island and continental (Junqueira and Ibicuí) of the outer zone. The number of species recorded in this study supporting the hypothesis that features of substratum and the availability of food and refuges are factors limiting the establishment of this family in Sepetiba Bay.

Probiotics have the potential to increase the efficiency and sustainability of aquaculture production. The mannan-oligosaccharides (MOS) are complex carbohydrates derived from the cell wall of the yeast Saccharomyces cerevisiae, which act by blocking adherence of bacterial lectins to carbohydrates on the surface of intestinal cells; this action prevents colonization and infection processes carried out by bacterial pathogens. In this work, we review the current evidence about the use of MOS as prebiotics in shellfish aquaculture, enlightening the positive responses in most of the experiences, such as improvement in growth and survival, modulating the immune response and modifying the morphology of the digestive tract. The identification of strains that are promoted or excluded, and the characterization of the resulting modulating action in gut's microbiota, remains open as one of the fields to be developed in conjunction with the extension of these results to the productive practice. [ABSTRACT FROM AUTHOR]

Se estableció la forma en que los machos del camarón Rhynchocinetes typus transfieren los espermatoforos durante la cópula. La fecundación es externa y durante el apareamiento, el primer y segundo par de pleopodos masculinos tienen una activa participación en la transferencia de espermatoforos al esternito de la hembra. La participación de estos pleopodos se determinó mediante el número de ovocitos fecundados que presentaron hembras que fueron apareadas con machos sexualmente maduros del tipo robustus con el Iº y/o 2° par de pleopodos amputado. Los resultados demostraron que las hembras apareadas con machos sin el primer y segundo par de pleopodos no fueron fecundadas y aquellas que fueron apareadas con machos sin el primer o el segundo par de pleopodos presentaron un 1,82% y 0,04% de ovocitos fecundados respectivamente, en relación a aquellas apareadas con machos sin amputación (100%). Estos resultados indican que ambos pares de pleopodos participan en la transferencia espermática.The manner in wich males of the rock shrimp Rhynchocinetes typus transfer spermatophores during mating was determined. Fecundation is external. The first and second pair of male pleopods play an active role in the transfer of sperm to the female's sternite. To he participation of these pleopods was determined by amputating the first, second, or both pairs of pleopods of sexually mature males of the type robustus. The number of fertilized eggs in the females was then counted. No fertilization was observed in he females that had mated with males lacking both the first and second pairs of pleopods. Females that had mated with males without either the first or second pair of pleopods presented (1.8% and 0.04%) fewer fertilized eggs than those females that had mated with intact males (100%). These results indicate that both pairs of pleopods particípate in the transfer of sperm.

Food production for aquaculture requires finding other protein sources or ingredients as potential alternatives in the formulation of aquaculture feeds, due to the shortage and high price of protein sources that are most commonly used. The aim of this analysis was to evaluate the relationship between the essential amino acids in 13 types of proteins available in the market with the essential amino acids found in the muscle of four of the most important farmed prawn species of the genus Macrobrachium (M. amazonicum, M. rosenbergii, M. americanum and M. tenellum). The results obtained showed the limiting amino acids of each ingredient for each species, thereby allowing for formulation of commercial foods that meet the nutritional needs to support optimal growth of these prawns in culture. In conclusion, there is a difference in the amino acids most often present as first limiting between sources of animal and plant origin. Thereby, it is possible evaluate complementarities between these sources to achieve an amino acids profile close to that of Macrobrachium species. [ABSTRACT FROM AUTHOR]

Parasitic copepods of the family Caligidae, the so-called sea lice, may be deleterious to marine or brackish finfish aquaculture. To date, biological and ecological studies of sea lice have been mostly restricted to species from cold or temperate regions. In Mexico there are some records of sea lice species on marine fishes; however, the research regarding their biology and ecology has been scarce. It is possible that a high biodiversity of sea lice is distributed in coastal waters of Mexico; therefore, their significance as pathogenic parasites should increase. The purpose of this review is to outline the current knowledge of the life cycle, host location, ecology, effect on fish health, and control strategies of sea lice in order to establish supportive basis for natural resource management and control of parasites and diseases of marine fish cultured in Mexico. [ABSTRACT FROM AUTHOR]

The manner in which males of the rock shrimp Rhynchocinetes typus transfer spermatophores during mating was determined. Fecundation is external. The first and second pair of male pleopods play an active role in the transfer of sperm to the female's sternite. To he participation of these pleopods was determined by amputating the first, second, or both pairs of pleopods of sexually mature males of the type robustus. The number of fertilized eggs in the females was then counted. No fertilization was observed in he females that had mated with males lacking both the first and second pairs of pleopods. Females that had mated with males without either the first or second pair of pleopods presented (1.8% and 0.04%) fewer fertilized eggs than those females that had mated with intact males (100%). These results indicate that both pairs of pleopods participate in the transfer of sperm. [ABSTRACT FROM AUTHOR]