Ecdysteroid titers and expression of Halloween genes and ecdysteroid receptor in relation to overwintering and the long larval phase in the seabuckthorn carpenterworm, Holcocerus hippophaecolus

2016 ◽  
Vol 160 (2) ◽  
pp. 133-146 ◽  
Author(s):  
Jiao Zhou ◽  
Juan Li ◽  
Rong Wang ◽  
Xia Sheng ◽  
Shixiang Zong ◽  
...  
Keyword(s):  
Ecdysteroid Receptor ◽  
Larval Phase ◽  
Holcocerus Hippophaecolus

scholarly journals Possible Dietary Effects of Insect-Based Diets across Zebrafish (Danio rerio) Generations: A Multidisciplinary Study on the Larval Phase

Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 751
Author(s):  
Matteo Zarantoniello ◽  
Basilio Randazzo ◽  
Gloriana Cardinaletti ◽  
Cristina Truzzi ◽  
Giulia Chemello ◽  
...  
Keyword(s):  
Fish Meal ◽  
Gut Health ◽  
Larval Phase ◽  
Nutritional Programming ◽  
Hepatic Lipid Accumulation ◽  
Zebrafish Larvae ◽  
Multidisciplinary Study ◽  
Substitution Level ◽  
Parental Feeding ◽  
Negative Side Effects

Insects represent a valuable and sustainable alternative ingredient for aquafeed formulation. However, insect-based diets have often highlighted controversial results in different fish species, especially when high inclusion levels were used. Several studies have demonstrated that nutritional programming through parental feeding may allow the production of fish better adapted to use sub-optimal aquafeed ingredients. To date, this approach has never been explored on insect-based diets. In the present study, five experimental diets characterized by increasing fish meal substitution levels with full-fat Black Soldier Fly (Hermetia illucens; BSF) prepupae meal (0%, 25%, 50%, 75% and 100%) were used to investigate the effects of programming via broodstock nutrition on F1 zebrafish larvae development. The responses of offspring were assayed through biometric, gas chromatographic, histological, and molecular analyses. The results evidenced that the same BSF-based diets provided to adults were able to affect F1 zebrafish larvae fatty acid composition without impairing growth performances, hepatic lipid accumulation and gut health. Groups challenged with higher BSF inclusion with respect to fish meal (50%, 75% and 100%) showed a significant downregulation of stress response markers and a positive modulation of inflammatory cytokines gene expression. The present study evidences that nutritional programming through parental feeding may make it possible to extend the fish meal substitution level with BSF prepupae meal in the diet up to almost 100% without incurring the well-known negative side effects of BSF-based diets.

Interpopulation variability of the reproductive cycle of Paracentrotus lividus (Echinodermata: Echinoidea) in the south-western Mediterranean

2000 ◽  
Vol 80 (5) ◽  
pp. 899-907 ◽  
Author(s):  
Mourad Guettaf ◽  
Gustavo A. San Martin ◽  
Patrice Francour
Keyword(s):  
Regional Scale ◽  
Gonad Index ◽  
Paracentrotus Lividus ◽  
Posidonia Oceanica ◽  
Western Mediterranean ◽  
Larval Phase ◽  
Spawning Period ◽  
Rocky Substrate ◽  
Maximum Value ◽  
Reproductive Cycles

The spawning of Paracentrotus lividus has been determined on the basis of the annual gonad index cycle at three sites in the Algiers area presenting low, intermediate and strong hydrodynamism. Three biotopes (Posidonia oceanica beds, rocky substrate with photophilous algae and overgrazed rocky substrate) and two depths (1–3 m and 6–10 m) were considered at these sites, the sex-ratio was always strongly in favour of females (2:1 to 3:1). In all sites but one, there were marked differences in the gonad index and the spawning period between sites; the gonad index reached its maximum value at the site with the weakest hydrodynamism, and the minimum value at the site with the strongest hydrodynamism. Spawning took place in April–May and August–September at the site with the weakest hydrodynamism, in April–June and October–December at the site with intermediate hydrodynamism and only in winter at the site with maximum hydrodynamism. The coexistence, on regional scale, of these reproductive cycles might enable Paracentrotus lividus to compensate the mortality during planktonic larval phase by the fact that spawning of this sea urchin occurred in all seasons.

Conformational changes in the DNA-binding domains of the ecdysteroid receptor during the formation of a complex with the hsp27 response element

2012 ◽  
Vol 30 (4) ◽  
pp. 379-393 ◽  
Author(s):  
Szymon Pakuła ◽  
Marek Orłowski ◽  
Grzegorz Rymarczyk ◽  
Tomasz Krusiński ◽  
Michał Jakób ◽  
...  
Keyword(s):  
Dna Binding ◽  
Conformational Changes ◽  
Response Element ◽  
Ecdysteroid Receptor ◽  
Dna Binding Domains ◽  
Binding Domains

Distribution, feeding behaviour, and condition of Cape horse mackerel early life stages, Trachurus capensis, under different environmental conditions in the northern Benguela upwelling ecosystem

2014 ◽  
Vol 72 (2) ◽  
pp. 543-557 ◽  
Author(s):  
S. J. Geist ◽  
A. Kunzmann ◽  
H. M. Verheye ◽  
A. Eggert ◽  
A. Schukat ◽  
...  
Keyword(s):  
Dissolved Oxygen ◽  
Feeding Ecology ◽  
Environmental Conditions ◽  
Early Life ◽  
Early Life History ◽  
Horse Mackerel ◽  
Larval Phase ◽  
Recruitment Success ◽  
Wide Range ◽  
Variable Recruitment

Abstract Early life history (ELH) traits are key to understand variable recruitment success and hence the stock size of marine fish. One of the currently most puzzling ecosystems in this regard is the northern part of the Benguela Current upwelling system off Namibia. Here, populations of the formerly dominant pelagic species, sardine and anchovy, failed to recover during the last three decades after a dramatic decline. In contrast, Cape horse mackerel, Trachurus capensis, maintained a constant population size. Warming of the system and shoaling of hypoxic zones together with feedback loops within an altered foodweb are discussed to be responsible for this regime shift. In this study, we address the role of larval traits for the successful performance of the T. capensis population under the present environmental conditions with the focus on feeding ecology. We investigated seasonal variations of the geographical distribution, growth rate, feeding ecology, and nutritional condition of their ELH stages and examined relationships with water temperature, dissolved oxygen concentration, and micro-zooplankton composition. T. capensis' ELH stages showed a wide spatial and seasonal distribution, a preference for higher water temperatures (18–21°C) and presence over a wide range of dissolved oxygen concentrations (0.13–6.35 ml O2 l−1). Feeding success was high and mainly different groups of Copepoda were targeted, which were strongly size selected. The high dietary importance of micro-copepods during large parts of the larval phase indicates successful exploitation of this food source, which has increased in abundance during the last decade. It also explains observed best nutritional conditions at temperatures between 18 and 21°C, since these small copepods are commonly associated with warmer temperatures. Altogether, these traits enhance the species' probability to encounter suitable environments for the survival of their ELH stages, which is likely to lead to their high recruitment success in the northern Benguela ecosystem.

scholarly journals Estimation of a closed population size of tadpoles in temporary pond

2017 ◽  
Vol 78 (2) ◽  
pp. 328-336
Author(s):  
M. S. C. S. Lima ◽  
J. Pederassi ◽  
C. A. S. Souza
Keyword(s):  
Population Size ◽  
Bayes Theorem ◽  
Venn Diagram ◽  
Temporary Pond ◽  
Larval Phase ◽  
Closed Population ◽  
Lotic Environment ◽  
Capture Recapture ◽  
Kolmogorov Smirnov ◽  
Smirnov Test

Abstract The practice of capture-recapture to estimate the diversity is well known to many animal groups, however this practice in the larval phase of anuran amphibians is incipient. We aimed at evaluating the Lincoln estimator, Venn diagram and Bayes theorem in the inference of population size of a larval phase anurocenose from lotic environment. The adherence of results was evaluated using the Kolmogorov-Smirnov test. The marking of tadpoles for later recapture and methods measurement was made with eosin methylene blue. When comparing the results of Lincoln-Petersen estimator corresponding to the Venn diagram and Bayes theorem, we detected percentage differences per sampling, i.e., the proportion of sampled anuran genera is kept among the three methods, although the values are numerically different. By submitting these results to the Kolmogorov-Smirnov test we have found no significant differences. Therefore, no matter the estimator, the measured value is adherent and estimates the total population. Together with the marking methodology, which did not change the behavior of tadpoles, the present study helps to fill the need of more studies on larval phase of amphibians in Brazil, especially in semi-arid northeast.

scholarly journals Hydrogen peroxide and chlorine dioxide against parasite Ichthyophthirius multifiliis (Protozoa, Ciliophora) in jundiá fingerlings

2017 ◽  
Vol 47 (12) ◽  
Author(s):  
Natalia da Costa Marchiori ◽  
Fabiano Muller Silva ◽  
Maurício Laterça Martins ◽  
Hilton Amaral Junior ◽  
Bruno Corrêa da Silva
Keyword(s):  
Hydrogen Peroxide ◽  
Chlorine Dioxide ◽  
Fish Farming ◽  
Control Group ◽  
Chemical Agent ◽  
Ichthyophthirius Multifiliis ◽  
Larval Phase ◽  
Group Data ◽  
Active Chemical ◽  
Continuous Bath

ABSTRACT: Ichthyophthiriasis is a worldwide fish disease with great financial impact on freshwater fish farming due to its associated high mortality rates. Current study assesses the parasiticidal capacity of hydrogen peroxide (H2O2) and chlorine dioxide (ClO2) against the causative agent, Ichthyophthirius multifiliis, in jundiá. Median lethal concentration (LC50, 96h) of each chemical agent was established, as well as the minimum inhibitory concentration of hydrogen peroxide for the parasite´s infectious larval phase (theront). Products were tested asynchronously in parasitized fingerlings for short and long baths at the following concentrations and exposure times: 1. Hydrogen peroxide: (T1) continuous bath - 30ppm and (T2) 50ppm; (T3) short bath - 150ppm, during 1h and (T4) 250ppm during 1h; control group (without any chemical agent). 2. Chlorine dioxide: (T1) continuous bath - 4ppm and (T2) 20ppm; (T3) short bath - 200ppm, during 1min; (T4) short bath - 400ppm, during 1min and control group. Data analysis demonstrated a concentration of 82.54ppm of the commercial product (or 24.76ppm of the active chemical agent) as LC50, 96h of H2O2 and 38.4ppm product (or 2.68ppm of the active chemical agent) for ClO2. Hydrogen peroxide concentration causing 100% mortality rate of theronts in 1h was 25ppm (product, or 7.5ppm of the active chemical agent). At the end of the fourth day of curative experiment, 98% of the animals died by ichthyophthiriasis. No treatment was effective against the parasite.

Significance of Egg and Larval Size to Recruitment Variability of Temperate Marine Fish

1991 ◽  
Vol 48 (10) ◽  
pp. 1820-1828 ◽  
Author(s):  
Pierre Pepin ◽  
Ransom A. Myers
Keyword(s):  
Life History ◽  
Marine Fish ◽  
Early Life ◽  
Univariate Analysis ◽  
Early Life History ◽  
Fish Populations ◽  
Larval Size ◽  
Larval Phase ◽  
Life History Stages ◽  
Recruitment Variability

Recruitment variability is commonly associated with fluctuations in abundance of marine fish populations. Previous studies have focussed on stock-specific correlative or mechanistic models or on comparisons of recruitment variations of several stocks or species. The purpose of this study is to determine whether recruitment variability of commercial marine fish populations is associated with either size or the duration of early life history stages. The analysis was performed with data from 86 stocks representing 21 species of commercial marine fish. Univariate analysis shows that neither egg size nor the length at hatch is significantly correlated with recruitment variability. The change in length during the larval phase, which is representative of the duration of the stage, is significantly positively correlated with recruitment variability. Multivariate analysis shows that recruitment variability increases with increasing length at metamorphosis but that recruitment variability is poorly associated with length at hatch. The degree of serial correlation is related to the relative duration of egg and larval stages. The results clearly indicate that recruitment variability is linked to characteristics of early life history stages.

scholarly journals Cucurbitacins are insect steroid hormone antagonists acting at the ecdysteroid receptor

1997 ◽  
Vol 327 (3) ◽  
pp. 643-650 ◽  
Author(s):  
Laurence DINAN ◽  
Pensri WHITING ◽  
Jean-Pierre GIRAULT ◽  
René LAFONT ◽  
S. Tarlochan DHADIALLA ◽  
...  
Keyword(s):  
Morphological Changes ◽  
Antagonistic Activity ◽  
Side Chain ◽  
Ecdysteroid Receptor ◽  
Whole Cells ◽  
Definitive Evidence ◽  
Permanent Cell ◽  
A Cell ◽  
Gel Shift Assay ◽  
Hormone Antagonists

Two triterpenoids, cucurbitacins B and D, have been isolated from seeds of Iberis umbellata (Cruciferae) and shown to be responsible for the antagonistic activity of a methanolic extract of this species in preventing the 20-hydroxyecdysone (20E)-induced morphological changes in the Drosophila melanogaster BII permanent cell line. With a 20E concentration of 50 nM, cucurbitacins B and D give 50% responses at 1.5 and 10 μM respectively. Both cucurbitacins are able to displace specifically bound radiolabelled 25-deoxy-20-hydroxyecdysone (ponasterone A) from a cell-free preparation of the BII cells containing ecdysteroid receptors. The Kd values for cucurbitacins B and D (5 and 50 μM respectively) are similar to the concentrations required to antagonize 20E activity with whole cells. Cucurbitacin B (cucB) prevents stimulation by 20E of an ecdysteroid-responsive reporter gene in a transfection assay. CucB also prevents the formation of the Drosophila ecdysteroid receptor/Ultraspiracle/20E complex with the hsp27 ecdysteroid response element as demonstrated by gel-shift assay. This is therefore the first definitive evidence for the existence of antagonists acting at the ecdysteroid receptor. Preliminary structure/activity studies indicate the importance of the Δ23-22-oxo functional grouping in the side chain for antagonistic activity. Hexanorcucurbitacin D, which lacks carbon atoms C-22 to C-27, is found to be a weak agonist rather than an antagonist. Moreover, the side chain analogue 5-methylhex-3-en-2-one possesses weak antagonistic activity.

scholarly journals Interspecific Variations in Duration of Tail Regression in Two Tropical Anurans

2015 ◽  
Vol 2015 ◽  
pp. 1-8
Author(s):  
Cuckoo Mahapatra ◽  
Pravati Kumari Mahapatra
Keyword(s):  
Environmental Conditions ◽  
Rainy Season ◽  
Larval Period ◽  
Evolutionary Strategies ◽  
Interspecific Difference ◽  
Extreme Temperatures ◽  
Larval Phase ◽  
Morphological Variations ◽  
Interspecific Variations ◽  
Tadpole Tail

Anurans breed in an array of habitats and hence employ a variety of evolutionary strategies to adapt to the variable conditions. Particularly, since they undergo a larval phase they develop mechanisms to overcome unfavourable conditions like desiccation, extreme temperatures, and so forth. The anurans, Polypedates maculatus and Duttaphrynus melanostictus, show noticeable variation in the duration of larval period and tadpole tail regression. D. melanostictus breeds throughout the year and hence is subjected to different environmental conditions as compared to P. maculatus which breeds only during the rainy season. Thus, the tadpoles of D. melanostictus have selected to undergo a shorter larval period and duration of tail regression to suit their breeding habits. The present study correlates the interspecific difference in the duration of tail regression with the morphological variations in the tails of the two species. D. melanostictus shortens the duration of larval tail regression by having comparatively larger and more number of melanocytes and a thinner notochord than P. maculatus.

Sign in / Sign up

Export Citation Format

Share Document