Search results for "Larvae"

Digestive Enzymes in Larvae and Juveniles of Farmed Sharpsnout Seabream (Diplodus puntazzo) (Cetti, 1777)

2011

The ontogenetic development and pattern of main digestive enzyme activities (proteases, carbohydrases and lipases) were investigated in farmed sharpsnout seabream Diplodus puntazzo larvae and juveniles, during the passage from the larval stage to adult (from 21 to 277 days after hatching - DAH). Larvae showed exponential growth, thus confirming that Rotifers and Artemia nauplii are suitable preys for early feeding of D. puntazzo larvae. Pepsin activity was low in the larvae, but it increased afterwards in relation with stomach development. In juveniles, levels of specific activity of trypsin, chymotrypsin and elastase were lower compared to that recorded in larvae. A decrease in the activit…

The hydrophilie of the larval test of Ascidiae: functional role played by test cells

2012

Ascidian swimming larvae are entirely surrounded by a hyaline extracellular coat, called as tunic or test, on which numerous test cells adhere. The functional role played by test cells in larvae of various ascidian species consists in depositing submicroscopic structures known as ornaments and/or substances of proteoglycan nature in the larval test surface. The deposition of ornaments would render the larval test hydrophilic and thus allow the larvae to swim being immersed in sea water. Ultrastructural investigations reported in literature on larvae of Cionidae and Ascididae families have not evidenced the presence of ornaments in the swimming larval test. For these Ascididae families it ha…

Signals from the deep-sea: Genetic structure, morphometric analysis, and ecological implications of Cyclothone braueri (Pisces, Gonostomatidae) early…

2020

Abstract Cyclothone braueri (Stomiiformes, Gonostomatidae) is a widely distributed fish inhabiting the mesopelagic zone of marine tropical and temperate waters. Constituting one of the largest biomasses of the ocean, C. braueri is a key element in most of the ecological processes occurring in the twilight layer. We focused on the ecological processes linked to early life stages in relation to marine pelagic environmental drivers (temperature, salinity, food availability and geostrophic currents) considering different regions of the Central Mediterranean Sea. A multivariate morphometric analysis was carried out using six parameters with the aim of discerning different larval morphotypes, whi…

Optogenetic Interpellation of Behavior Employing Unrestrained Zebrafish Larvae

2017

Fatty-acid preference changes during development in Drosophila melanogaster.

2011

WOS:000296521400044; International audience; Fatty-acids (FAs) are required in the diet of many animals throughout their life. However, the mechanisms involved in the perception of and preferences for dietary saturated and unsaturated FAs (SFAs and UFAs, respectively) remain poorly explored, especially in insects. Using the model species Drosophila melanogaster, we measured the responses of wild-type larvae and adults to pure SFAs (14, 16, and 18 carbons) and UFAs (C18 with 1, 2, or 3 double-bonds). Individual and group behavioral tests revealed different preferences in larvae and adults. Larvae preferred UFAs whereas SFAs tended to induce both a strong aversion and a persistent aggregation…

Larval zebrafish as an in vitro model for evaluating toxicological effects of mycotoxins.

2020

The presence of mycotoxins in food has created concern. Mycotoxin prevalence in our environment has changed in the last few years maybe due to climatic and other environmental changes. Evidence has emerged from in vitro and in vivo models: some mycotoxins have been found to be potentially carcinogenic, embryogenically harmful, teratogenic, and to generate nephrotoxicity. The risk assessment of exposures to mycotoxins at early life stages became mandatory. In this regard, the effects of toxic compounds on zebrafish have been widely studied, and more recently, mycotoxins have been tested with respect to their effects on developmental and teratogenic effects in this model system, which offers …

Probiotic properties of Brevibacillus brevis and its influence on sea bass (Dicentrarchus labrax) larval rearing

2012

Efficacy of Brevibacillus brevis strain and its influence on larval rearing of sea bass (Dicentrarchus labrax) were investigated in the present work. Biochemical analyses permit to identify this strain as B. brevis. This bacterium has an inhibitory effect against fish pathogenic bacteria, especially the genus of Vibrio. Enzymatic characterization revealed that B. brevis was lipase positive, amylase, lecithinase and caseinase negative. Adherence assays to abiotic surfaces and challenge test with Artemia larvae demonstrate that B. brevis was fairly adherent and play an important role in the enhancement of the protection of Artemia culture against pathogens. Treatment of sea bass larvae with B…

Assessment of nursing and midwifery students’ knowledge of treatment of diabetic foot syndrome using Lucilia servicata larvae

2021

Background. Diabetes mellitus is one of the most common chronic diseases, and in recent years its prevalence has been systematically increasing. Untreated or ineffectively treated diabetes leads to the development of many complications. Among these that can significantly affect the quality of life is diabetic foot syndrome (DFS). Larvotherapy is a therapeutic method of treating wounds arising during the course of DFS. Aim of the study. The main objective of this study was to assess the level of knowledge of nursing and midwifery students on the treatment of DFS using Lucilia sericata larvae. Material and Methods. This study is a cross-sectional, observational study in which 202 nursing and …

Engraulis encrasicolus larvae from two different environmental spawning areas of the Central Mediterranean Sea: first data on amino acid profiles and…

2020

Early life stages of marine fish populations may be strongly affected by environmental factors. Changes in the physical environment or the availability of food resources could lead to stress-related physiological responses affecting larval fitness, growth and survival. In the present study, we determined, for the first time, amino acid composition (AAC), lipid, and carbohydrate content, as well as alkaline phosphatase and peroxidase activities in larvae from the European anchovy Engraulis encrasicolus. Fishes were caught in two different spawning areas of the Strait of Sicily, characterized by different environmental conditions, including a coastal upwelling with a lower temperature (Advent…

Ultrastructural comparative analysis on the adhesive papillae of the swimming larvae of three ascidian species

2009

This paper presents a preliminary report on the papillae of the swimming larvae of three ascidian species: Ascidia malaca, Phallusia mammillata and Ciona intestinalis. The investigations, carried out at ultrastructural level and at confocal laser microscope, have evidenced, in the adhesive papillae of the three studied species, three different cell-types: axial columnar cells, collocytes, sensory cells respectively. The adhesive papillae of A. malaca and P. mammillata show central axial columnar cells with long microvilli emerging from the apical edge and extending throughout the hyaline cap. Collocytes are elongated secreting cells, lying in middle-lateral side. Sensory cells have a cilium…