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Saline Systems May 2006The XI International Rotifer Symposium was held during 11-18 March, 2006 at the National Autonomous University of Mexico Campus Iztacala located at the North Mexico City...
The XI International Rotifer Symposium was held during 11-18 March, 2006 at the National Autonomous University of Mexico Campus Iztacala located at the North Mexico City (Mexico). These triennial international meetings, first organized in Austria by Late Ruttner-Kolisko in September 1976, are gradually becoming the focal point of discussion and collaboration from rotifer workers across the world. The present XI symposium was attended by 125 participants from 20 nations. During this meeting, different themes of rotifer research from morphology to molecular biology were considered. In addition, there were four invited lectures and four workshops covering different themes of the symposium. During the last 30 years, rotifer research has witnessed gradual shift from the conventional morphological taxonomy to molecular and evolutionary systematics. While the basic rotifer ecological studies continue today, applied areas such as ecotoxicology and aquaculture have taken key roles in the recent meetings. The international rotifer meetings provide ample opportunities not only for exchange of ideas and recent research, but also for material and in establishing inter-personal relationships. Over the last 30 years, the number of participants attending the rotifer meetings has increased.
PubMed: 16700910
DOI: 10.1186/1746-1448-2-6 -
PloS One 2023The 5-hydroxytrptamine 3 (5-HT3) receptor is a member of the 'Cys-loop' family and the only pentameric ligand gated ion channel among the serotonin receptors. 5-HT3...
The 5-hydroxytrptamine 3 (5-HT3) receptor is a member of the 'Cys-loop' family and the only pentameric ligand gated ion channel among the serotonin receptors. 5-HT3 receptors play an important role in controlling growth, development, and behaviour in animals. Several 5-HT3 receptor antagonists are used to treat diseases (e.g., irritable bowel syndrome, nausea and emesis). Humans express five different subunits (A-E) enabling a variety of heteromeric receptors to form but all contain 5HT3A subunits. However, the information available about the 5-HT3 receptor subunit occurrence among the metazoan lineages is minimal. In the present article we searched for 5-HT3 receptor subunit homologs from different phyla in Metazoa. We identified more than 1000 5-HT3 receptor subunits in Metazoa in different phyla and undertook simultaneous phylogenetic analysis of 526 5HT3A, 358 5HT3B, 239 5HT3C, 70 5HT3D, and 173 5HT3E sequences. 5-HT3 receptor subunits were present in species belonging to 11 phyla: Annelida, Arthropoda, Chordata, Cnidaria, Echinodermata, Mollusca, Nematoda, Orthonectida, Platyhelminthes, Rotifera and Tardigrada. All subunits were most often identified in Chordata phylum which was strongly represented in searches. Using multiple sequence alignment, we investigated variations in the ligand binding region of the 5HT3A subunit protein sequences in the metazoan lineage. Several critical amino acid residues important for ligand binding (common structural features) are commonly present in species from Nematoda and Platyhelminth gut parasites through to Chordata. Collectively, this better understanding of the 5-HT3 receptor evolutionary patterns raises possibilities of future pharmacological challenges facing Metazoa including effects on parasitic and other species in ecosystems that contain 5-HT3 receptor ligands.
Topics: Animals; Humans; Receptors, Serotonin, 5-HT3; Phylogeny; Serotonin; Ecosystem; Ligands; Chordata
PubMed: 36857360
DOI: 10.1371/journal.pone.0281507 -
Zebrafish Jun 2018The current body of work on rearing larval/juvenile zebrafish is based on (1) utilization of freshwater and (2) diurnal light/dark cycle, (3) provision of live feed at...
The current body of work on rearing larval/juvenile zebrafish is based on (1) utilization of freshwater and (2) diurnal light/dark cycle, (3) provision of live feed at modest density, and (4) culture in high visibility environment. We challenged these rearing approaches by maintaining zebrafish under constant light for 46-48 days (days postfertilization [dpf]), while securing continuous feeding in high turbidity and saline (1.8-2.1 parts per thousand) environment for the experiment's duration, allowing 24 h feeding/growth of fish from first exogenous feeding to maturation. There was no evidence of negative effects on zebrafish larvae behavior, growth, survival, and life cycle duration at constant illumination when food was continuously available. Zebrafish were stocked at high initial density (100 larvae/L) in a static system and fed high densities of rotifers (Brachionus plicatilis) (200-400/mL) from 6 to 12 dpf. Fish density was then reduced by 50% and two diet treatments, live rotifers or brine shrimp (Artemia) nauplii (10/mL), followed. Fish were reared on these two diets until first maturation. Performance of adult zebrafish fed live rotifer followed by Artemia nauplii diet was the highest recorded in the literature after 42 dpf, 250 ± 29 (males) and 430 ± 5 mg (females). Use of these rearing conditions, during the entire life cycle, until reproduction, resulted in the shortest ever recorded generation time (from egg to egg) of 43-45 dpf and fertilization rate (1 dpf) of 80.3%-94%.
Topics: Animal Feed; Animal Husbandry; Animals; Artemia; Diet; Larva; Rotifera; Survival Rate; Zebrafish
PubMed: 29485943
DOI: 10.1089/zeb.2017.1515 -
Zebrafish Aug 2019We present a novel, low-footprint and low-cost semi-automatic system for delivering solid and liquid food to zebrafish, and more generally to aquatic animals raised in...
We present a novel, low-footprint and low-cost semi-automatic system for delivering solid and liquid food to zebrafish, and more generally to aquatic animals raised in racks of tanks. It is composed of a portable main module equipped with a contactless reader that adjusts the quantity to deliver for each tank, and either a solid food module or a liquid food module. Solid food comprises virtually any kind of dry powder or grains below 2 mm in diameter, and, for liquid-mediated food, brine shrimps () and rotifers () have been successfully tested. Real-world testing, feedback, and validation have been performed in a zebrafish facility for several months. In comparison with manual feeding this system mitigates the appearance of musculoskeletal disorders among regularly-feeding staff, and let operators observe the animals' behavior instead of being focused on quantities to deliver. We also tested the accuracy of both humans and our dispenser and found that the semi-automatic system is much more reliable, with respectively 7-fold and 84-fold drops in standard deviation for solid and liquid food.
Topics: Animal Feed; Animal Husbandry; Animals; Artemia; Food Dispensers, Automatic; Housing, Animal; Rotifera; Zebrafish
PubMed: 31237527
DOI: 10.1089/zeb.2019.1733 -
Ecotoxicology and Environmental Safety Aug 2023Ultraviolet B (UV-B, 280-320 nm) radiation is a major environmental stressor for aquatic organisms on Earth's surface. Its effects on biological systems are well known,...
Ultraviolet B (UV-B, 280-320 nm) radiation is a major environmental stressor for aquatic organisms on Earth's surface. Its effects on biological systems are well known, but the mechanisms by which organisms respond and adapt to UV-B radiation are still being explored. In this study, we investigated the effects of UV-B radiation on the monogonont rotifer Brachionus asplanchnoidis, focusing on physiological parameters, antioxidant systems, DNA damage, and DNA repair-related molecular mechanism. Our results showed that the LD was at 28.53 kJ/m, indicating strong tolerance to UV-B. However, UV-B radiation caused adverse effects on growth and reproduction, with shortened reproductive period and longevity, decreased fecundity and hatchability, and inhibition of population growth. Biochemical analyses revealed severe oxidative damage and lipid peroxidation, with increased ROS and MDA levels. Activities of antioxidant enzymes were highly induced at low doses but decreased at high doses. DNA damage also occurred in UV-B-exposed rotifers. Furthermore, selected DNA repair-related genes were up-regulated in a dose-dependent manner. These findings provide a comprehensive understanding of the effects of UV-B radiation on rotifers and highlight the importance of considering both ecological and molecular responses in assessing the impact of UV-B radiation on aquatic organisms.
PubMed: 37542982
DOI: 10.1016/j.ecoenv.2023.115319 -
Marine Pollution Bulletin Aug 202316S rRNA gene sequencing and bacteria- and genus-specific quantitative PCR was used to profile microbial communities and their associated functions in water, live feed...
16S rRNA gene sequencing and bacteria- and genus-specific quantitative PCR was used to profile microbial communities and their associated functions in water, live feed (microalgae, Artemia, and rotifer), and European sea bass and gilthead sea bream larvae from hatcheries in Greece and Italy. The transfer to larvae of genus containing potential pathogens of fish was more likely with Artemia and rotifer than with microalgae or water, irrespective of geographic location. The presence of potentially pathogenic bacteria (Vibrio and Pseudoalteromonas) in the core microbiota of water, live feed, and fish larvae, the enrichment of different bacterial resistance pathways and biofilm formation, and the overall low beneficial bacteria load during larval ontogeny emphasizes the risk for disease outbreaks. The present data characterizing microbiota in commercial aquaculture hatcheries provides a baseline for the design of strategies to manage disease and to model or remediate potential adverse environmental impacts.
Topics: Animals; RNA, Ribosomal, 16S; Aquaculture; Microbiota; Rotifera; Vibrio; Larva; Water
PubMed: 37441915
DOI: 10.1016/j.marpolbul.2023.115218 -
ZooKeys 2020Bdelloid rotifers are a group of microscopic invertebrates known for their obligate parthenogenesis and exceptional resistance to extreme environments. Their diversity...
Bdelloid rotifers are a group of microscopic invertebrates known for their obligate parthenogenesis and exceptional resistance to extreme environments. Their diversity and distributions are poorly studied in Asia, especially in China. In order to better understand the species distribution and diversity of bdelloid rotifers in China, a scientific surveys of habitats was conducted with 61 samples (both terrestrial and aquatic habitats) from 11 provinces and regions of China, ranging from tropics to subtropics with a specific focus on poorly sampled areas (Oriental) during September 2017 to October 2018. A total of 59 morphospecies (including subspecies) were found, of which, thirty-nine morphospecies (including one genus) are new records for China, almost doubling the number of previous records. Four rare morphospecies (Adineta cf. acuticornis Haigh, e Örstan, De Koning and Donner) are depicted and redescribed, and an updated checklist of Chinese bdelloids with their location and ecological information is presented. This study provides new data from a large region of China, enriching the knowledge of bdelloid biodiversity, and their global biogeography.
PubMed: 32595405
DOI: 10.3897/zookeys.941.50465 -
Scientific Reports Dec 2022Colonisation of crustacean zooplankton with ciliate epibionts is widespread in freshwater and marine environments. However, the ecology of such association are little...
Colonisation of crustacean zooplankton with ciliate epibionts is widespread in freshwater and marine environments. However, the ecology of such association are little studied as yet. The occurrence of ciliate epibionts on copepods and the preference towards this association with different life stages of Mesocyclops were studied from winter to spring. Relative susceptibility of zooplankton species was evaluated by analysing the epibiont colonies and zooids and relate this to the surface area of the host. The maximum epibiont infestation per unit body surface area was recorded on copepodites followed by copepod nauplii rather than other zooplankton species, whereas the rotifer Asplanchna was never affected. Influence of climatic factors such as temperature on the colonisation of epibionts on basibionts was found significant. In winter (November to February) samples, copepods were infested by autotrophic epibionts whereas in late spring and early summer (March-April) heterotrophic protists (peritrichian ciliates) were the sole epibionts on copepods. We conducted experiments in the laboratory on prey selection pattern of predators by direct visual and video-graphic observations of various events (encounter, attack, capture, ingestion, prey escape) during predation by infested and uninfested copepodites and adults of Mesocyclops. Postencounter the attack probability was significantly lower in infested than in uninfested copepods. The present paper reports on substrate preference by epibionts and their impacts in food rich and food scarce environments. Furthermore, major environmental interactions were studied with the reproductive phenology of copepods with respect to epibionts and the cause and effect of long term association of epibionts with copepods need to be addressed.
Topics: Animals; Copepoda; Predatory Behavior; Fresh Water; Temperature; Rotifera; Zooplankton; Ciliophora
PubMed: 36587046
DOI: 10.1038/s41598-022-26004-5 -
Chemosphere Nov 2022The shrinking of the Aral Sea represents one of the greatest ecological disasters of modern time. The data on the surviving northern part (Small Aral) is scarce and...
The shrinking of the Aral Sea represents one of the greatest ecological disasters of modern time. The data on the surviving northern part (Small Aral) is scarce and requires an update. This study aimed to analyze the chemistry, phyto- and zooplankton composition, and their relation in the waters of the Small Aral and its tributary, Syr Darya River. The chemistry of both ecosystems was significantly different. Small Aral was characterized by higher ionic concentrations, salinity, and electric conductivity and more significant spatial variation of chemical properties. The area near the river mouth was more pristine, while the ions concentration and salinity in the distant bays were much higher (>10‰). The highest concentrations of nitrates and total phosphorus in the Syr Darya were observed near Kyzylorda, indicating urban pollution. Overall, 109 phytoplankton taxa were identified in both ecosystems, with diatoms, green algae, and cyanobacteria being most abundantly represented. Oligohalobes dominated, but no polyhalobes and euhalobes algal species were identified. In total, 27 taxa of zooplankton were identified in both studied ecosystems, with the domination of rotifers over microcrustaceans. An exceptionally high level of dominance (65-91%) of rotifer Keratella cochlearis in the Syr Darya was found. The phyto- and zooplankton species richness was higher in the Syr Darya. Plankton communities of the Small Aral reflected horizontal variability of chemical properties. The total phosphorus promoted the prevalence of diatoms, rotifers, and crustaceans. Increased nitrogen concentration promoted cyanobacteria, chlorophytes, cryptophytes and chrysophytes, and rotifers Keratella cochlearis and K. quadrata. The abundance of dinophytes, diatoms Navicula cryptotenella and Cocconeis placentula, green algae Mychonastes jurisii and rotifer Keratella tecta was driven by the higher alkalinity and conductivity/salinity levels. The results represent a reference point for future monitoring of the area and add to understanding the complexity of biological transformations in the Aral Sea and its tributary.
Topics: Animals; Cyanobacteria; Diatoms; Ecosystem; Nitrogen; Phosphorus; Phytoplankton; Plankton; Rivers; Rotifera; Zooplankton
PubMed: 35872058
DOI: 10.1016/j.chemosphere.2022.135788 -
Scientific Reports Mar 2022Water turbidity can significantly influence interspecific interactions in aquatic ecosystems. We tested the hypothesis that the turbidity gradient significantly...
Water turbidity can significantly influence interspecific interactions in aquatic ecosystems. We tested the hypothesis that the turbidity gradient significantly differentiates the dynamics, significance and type of relationships in the structure of zooplankton communities colonizing mine pit reservoirs. The interactions between zooplankton species were evaluated by network graph analysis for three water turbidity classes: high turbidity (HT), moderate turbidity (MT) and low turbidity (LT). The HT network was most cohesive, and it was controlled by taxa grazing on various food sources within one ecological niche (Polyarthra longiremis, Brachionus angularis, Cyclops vicinus, Codonella cratera) and the positive and negative relationships between them were balanced. The MT biocenotic network was composed of three sub-networks connected by nodes with high communication attributes (Polyarthra vulgaris, Bosmina longirostris, C. vicinus), and antagonistic interactions (predation and competition) were less important. The LT network was most heterogeneous, and Daphnia cuculllata exerted the strongest influence on the network's structure by forming numerous positive (coexistence with predators) and negative (interference competition with microphagous rotifers) interspecific relationships. The study provides new information about the ecology of aquatic ecosystems, that are disturbed by changes in water turbidity.
Topics: Animals; Cladocera; Ecosystem; Rotifera; Water; Zooplankton
PubMed: 35273316
DOI: 10.1038/s41598-022-08045-y