Mikrocytids Are a Broadly Distributed and Divergent Radiation of Parasites in Aquatic Invertebrates

publisher: Elsevier articletitle: Mikrocytids Are a Broadly Distributed and Divergent Radiation of Parasites in Aquatic Invertebrates journaltitle: Current Biology articlelink: http://dx.doi.org/10.1016/j.cub.2014.02.033 content_type: article copyright: Copyright © 2014 The Authors. Published by Elsevier Ltd.The file attached is the Published/publisher’s pdf version of the articl

A global review of problematic and pathogenic parasites of farmed tilapia

Over the past 80 years, tilapia have been translocated globally for aquaculture; active production is recorded in >124 countries. Of 7 million tonnes of tilapia produced in aquaculture, 79% is from 79 countries outside the natural range of tilapia. Capture fisheries account for a further 723,627 tonnes of tilapia, and >47% of this is landed from established invasive populations outside Africa. Tilapias host a rich fauna of parasites, many of which have been translocated with their hosts. This review summarises >2500 host–parasite records from 73+ countries and >820 recorded tilapia translocations (provided in the supplementary materials). This work focuses on the notable pathogens that threaten the health of cultured populations of tilapia, providing a description of their pathology and includes species that also have substantial impacts on wild tilapia populations, where relevant. For each major parasite taxonomic group, we highlight which parasites have been translocated or have been acquired from the new environments into which tilapia have been introduced, together with remarks on standard treatment approaches and research on them and their management and control. Regarding the theme ‘Tilapia health: quo vadis?’, Africa has enormous potential for aquaculture growth, but substantial knowledge gaps about tilapia parasites in many African states remain, which creates associated production and biosecurity risks. For each parasitic group, therefore, the risks of parasite translocation to new regions as tilapia aquaculture industries expand are highlighted

The Magnitude of Global Marine Species Diversity

Background: The question of how many marine species exist is important because it provides a metric for how much we do and do not know about life in the oceans. We have compiled the first register of the marine species of the world and used this baseline to estimate how many more species, partitioned among all major eukaryotic groups, may be discovered. Results: There are ∼226,000 eukaryotic marine species described. More species were described in the past decade (∼20,000) than in any previous one. The number of authors describing new species has been increasing at a faster rate than the number of new species described in the past six decades. We report that there are ∼170,000 synonyms, that 58,000–72,000 species are collected but not yet described, and that 482,000–741,000 more species have yet to be sampled. Molecular methods may add tens of thousands of cryptic species. Thus, there may be 0.7–1.0 million marine species. Past rates of description of new species indicate there may be 0.5 ± 0.2 million marine species. On average 37% (median 31%) of species in over 100 recent field studies around the world might be new to science. Conclusions: Currently, between one-third and two-thirds of marine species may be undescribed, and previous estimates of there being well over one million marine species appear highly unlikely. More species than ever before are being described annually by an increasing number of authors. If the current trend continues, most species will be discovered this century

Ultrastructural characterisation of Marteilia species (Paramyxea) from Ostrea edulis, Mytilus edulis and Mytilus galloprovincialis in Europe

6 pages, 1 figure, 2 tables.A focused ultrastructural study of Marteilia spp. found in cultured Ostrea edulis, Mytilus edulis and Mytilus galloprovincialis from France and Spain was conducted with emphasis placed on haplosporosomes, striated plate-like inclusions and spore wall morphology. Two types of haplosporosome were identified, sphaeroid and oblate, which were common to the parasite in all 3 host species. A total of 492 haplosporosomes were measured; those from the Marteilia sp. in Mytilus spp. were marginally smaller than those in Ostrea edulis. Spore wall morphology was found to vary depending on the state of maturity of the parasite‹the more mature the parasite, the thicker the wall surrounding it. It is suggested that the current criteria used to distinguish M. maurini from M. refringens are invalid and that M. maurini was relegated to a junior synonym of M. refringens.This work was supported by European Union FAIR contract 94C 85/13.Peer reviewe

Susceptibility of a number of bivalve species to the protozoan parasite Bonamia ostreae and their ability to act as vectors for this parasite

8 pages, 1 figure, 7 tables.The protozoan parasite Bonamia ostreae (Pichot et al., 1980) is a serious pathogen of the native European flat oyster Ostrea edulis. Field and laboratory based experiments were carried out in Ireland and Spain to investigate the susceptibility to this protozoan of the Pacific oyster Crassostrea gigas, the mussels Mytilus edulis and Mytilus galloprovincialis, the European native clam Ruditapes decussatus and the Manila clam Ruditapes philippinarum. Their ability to act as vectors or intermediate hosts was also investigated. The study corroborated previous findings that demonstrated that flat oysters can be successfully infected both naturally in the field and experimentally in the laboratory, and the pathogen can be transmitted directly between flat oysters in the laboratory. However, the other bivalves tested could not be infected with the parasite either naturally or experimentally, and these bivalves did not appear to act as vectors or intermediate hosts for the parasite. These results have implications for movements of bivalves between areas within the European Union.This work was supported by European Union FAIR contract 94C 85/13.Peer reviewe

A Natural Gas Fermentation Bacterial Meal (FeedKind®) as a Functional Alternative Ingredient for Fishmeal in Diet of Largemouth Bass, Micropterus salmoides

A 10-week growth study was conducted to evaluate the effect of a natural gas fermentation bacterial meal (FeedKind®, FK) as a fishmeal (FM) alternative in largemouth bass (Micropterus salmoides) (48.0 ± 0.03 g). Four isonitrogenous and isoenergetic diets were formulated including one commercial control (C, 42% FM) and three experimental diets with gradient FK of 3% (FK3, 29%FM), 6% (FK6, 26%FM) and 9% (FK9, 23%FM), respectively. FK-fed groups showed significantly higher SR than that of C group. The WGR and SGR of fish fed FK3 and FK6 were significantly higher than those of FK9, but not statistical different from the C group. FK-fed groups showed higher apparent digestibility coefficients of dry matter and nutrients. Further, FK-fed groups increased the ratio of SOD/MDA in the plasma and liver, and the upregulation of intestinal Keap1 and downregulation of HIF1α was found in FK3. Furthermore, FK-fed groups showed higher microbial richness and diversity. Pearson correlation analysis found that antioxidant relevant biomarkers were negatively correlated with the relative abundance of certain potential beneficial bacteria. In conclusion, supplemented up to 3–6% FK replacing FM in a low FM diet of largemouth bass could increase growth, survival rate, antioxidant capacity, and improve gut microbiota

Effects of a novel bacteria meal (FeedKind®) on the physical properties of extrudates

The development of fishmeal (FM) alternatives for feed in aquaculture is essential for sustainable and economic fish farming. A study was undertaken to evaluate the potential of a novel bacteria meal (FeedKind® (FK)) as fishmeal substitute. There are significant differences between fishmeal and FeedKind® in viscosity, water absorption, water-soluble protein, oil absorption and other physicochemical properties, which in turn affects the physical quality of feed. Increasing FK content will enhance the pellet durability (P < 0.05) and the expansion (P < 0.01), and decrease the oil leakage (P < 0.05) of the extruded feed pellets. This indicates that FK can be used as a feasible substitute for FM to improve the physical qualities of low-starch floating extrudates. The optimal lower moisture content (24.3%−24.9%) and temperature (127.6 ℃−136.7 ℃) requirement in extrusion after FM is replaced by FK is conducive to reducing the consumption of water and electric energy in the drying process, which contributes to the low carbon emissions and sustainable production of fish feed

Strengths and Weaknesses of the Management and Monitoring of Deep-Water Stocks, Fisheries, and Ecosystems in Various Areas of the World—A Roadmap Toward Sustainable Deep-Water Fisheries in the Northeast Atlantic?

Scientific interest in deep-water marine resources has increased dramatically over the last 10-20 years, as management bodies have sought advice on how to manage deep-water fisheries and protect deep-water ecosystems. The strengths and weaknesses of the management and monitoring of deep-water stocks, fisheries and ecosystems in various areas of the world are described, with the objective of informing the EU FP7 DEEPFISHMAN Project so that it can fulfil its primary aim which is to develop strategic options for a short- and long-term management and monitoring ecosystem-based framework for the NE Atlantic. To provide a baseline, the current monitoring and management regime in the NE Atlantic is reviewed, followed by a brief description of the regimes applying to deep-water fisheries in the north-west Atlantic the south-east Atlantic, off Brazil, in the Antarctic, off Australia and New Zealand and in the Mediterranean. The strengths and weaknesses of these are then discussed, taking into account additional information available from DEEPFISHMAN Case Study stocks, outcomes from consultations with stakeholders in the deep-water fishing industry in the NE Atlantic, and the requirements of EU regulations and developing policy that will likely impact on deep-water fisheries in the NE Atlantic.JRC.G.4-Maritime affair