Molecular characterization of the myoliquefactive fish parasite kudoa mirabilis (Cnidaria, kudoidae) from se Indian Ocean and its phylogenetic relationship with the kudoa thyrsites species complex

Myxosporean parasites of the genus Kudoa are fish parasites of great economic importance, as some species can affect the fish fillet quality by producing macroscopic cysts or generating post mortem myoliquefaction, commonly referred to as ‘soft flesh’. Kudoa mirabilis is a ‘soft flesh’-inducing species originally described based on morphology in the musculature of Trichiurus lepturus from the Indian Ocean. An integrative morphological and genetic characterization of K. mirabilis from the type host caught off the coast of Tanzania is here provided. The spores were stellate with four unequal polar capsules, showing similarities to Kudoa thyrsites. For comparative and validation purpose, K. mirabilis was compared morphologically and genetically with K. thyrsites reference isolates, including new obtained samples from the type host Thyrsites atun caught in the SE Atlantic Ocean. Morphological analyses of spores revealed key diagnostic characters clearly distinguishing the two Kudoa species. Phylogenetic analyses based on SSU and LSU rRNA genes demonstrated that K. mirabilis is a distinct and valid species, representing a sister group to a K. thyrsites subclade that comprises several isolates from Japan and one single isolate from South Africa. This finding raises questions about the true diversity likely hidden in the K. thyrsites complex.publishedVersio

Anisakid nematodes in Trichiurus lepturus and Saurida undosquamis (Teleostea) from the South-West Indian Ocean: Genetic evidence for the existence of sister species within Anisakis typica (s.l.), and food-safety considerations

Nematode parasites of the genus Anisakis (Nematoda, Anisakidae) are considered among the most important biological hazards in seafood products worldwide. In temperate and tropical waters, the most common species appears to be Anisakis typica, generally found around the viscera and sporadically in the flesh of various fish host species. This study investigated the infection sites and genetic diversity of A. typica infecting commercial fishes from the South-West Indian Ocean. Largehead hairtail (N = 20) and brushtooth lizardfish (N = 72) fished off Tanzania were inspected for anisakid nematodes by UV-press. A subsample of 168 nematodes were identified by sequence analyses of the cox2 mtDNA gene and ITS region of rDNA. The species A. typica (s.l.) (N = 166), Pseudoterranova ceticola (N = 1) and Anisakis paggiae (N = 1) were molecularly identified. Phylogenetic analysis of A. typica (s.l.) sequences based on both genes, indicated the existence of two distinct phylogenetic lineages forming two well-supported clades. The first clade comprised 12 A. typica specimens including individuals from its type locality (central Atlantic Ocean). The second clade comprising 154 specimens, clustered with reference sequences retrieved from GenBank including one apparently undescribed taxon, i.e., Anisakis sp. 1, and A. typica var. indonesiensis. The two reciprocally monophyletic clades are closely related and correspond to two distinct sister species within A. typica (s.l.), presently indicated as A. typica sp. A and A. typica sp. B. Two and four fixed alternative nucleotide substitutions (SNPs), i.e., diagnostic positions, between the two taxa, respectively, were found at the mtDNA cox2 and the ITS region of rDNA. The genetic data, as well as their occurrence in sympatry, strengthens the hypothesis that the actual specimens represent two distinct gene pools. The occurrence of both A. typica sp. A and A. typica sp. B in the musculature of freshly examined T. lepturus and S. undosquamis, suggests that both species can migrate intra-vitam into the flesh. Although the zoonotic potential of A. typica s.l. is still unclear, the presence of these parasites in the musculature, edible part of the fish, raises health concerns for consumers.publishedVersio

The small pelagic fishery of the Pemba Channel, Tanzania: what we know and what we need to know for management under climate change

Small pelagic fish, including anchovies, sardines and sardinellas, mackerels, capelin, hilsa, sprats and herrings, are distributed widely, from the tropics to the far north Atlantic Ocean and to the southern oceans off Chile and South Africa. They are most abundant in the highly productive major eastern boundary upwelling systems and are characterised by significant natural variations in biomass. Overall, small pelagic fisheries represent about one third of global fish landings although a large proportion of the catch is processed into animal feeds. Nonetheless, in some developing countries in addition to their economic value, small pelagic fisheries also make an important contribution to human diets and the food security of many low-income households. Such is the case for many communities in the Zanzibar Archipelago and on mainland Tanzania in the Western Indian Ocean. Of great concern in this region, as elsewhere, is the potential impact of climate change on marine and coastal ecosystems in general, and on small pelagic fisheries in particular. This paper describes data and information available on Tanzania's small pelagic fisheries, including catch and effort, management protocols and socio-economic significance

Molecular characterization of the myoliquefactive fish parasite kudoa mirabilis (Cnidaria, kudoidae) from se Indian Ocean and its phylogenetic relationship with the kudoa thyrsites species complex

Myxosporean parasites of the genus Kudoa are fish parasites of great economic importance, as some species can affect the fish fillet quality by producing macroscopic cysts or generating post mortem myoliquefaction, commonly referred to as ‘soft flesh’. Kudoa mirabilis is a ‘soft flesh’-inducing species originally described based on morphology in the musculature of Trichiurus lepturus from the Indian Ocean. An integrative morphological and genetic characterization of K. mirabilis from the type host caught off the coast of Tanzania is here provided. The spores were stellate with four unequal polar capsules, showing similarities to Kudoa thyrsites. For comparative and validation purpose, K. mirabilis was compared morphologically and genetically with K. thyrsites reference isolates, including new obtained samples from the type host Thyrsites atun caught in the SE Atlantic Ocean. Morphological analyses of spores revealed key diagnostic characters clearly distinguishing the two Kudoa species. Phylogenetic analyses based on SSU and LSU rRNA genes demonstrated that K. mirabilis is a distinct and valid species, representing a sister group to a K. thyrsites subclade that comprises several isolates from Japan and one single isolate from South Africa. This finding raises questions about the true diversity likely hidden in the K. thyrsites complex

Evidence of localised upwelling in Pemba Channel (Tanzania) during the southeast monsoon

Oceanographic and biogeochemical observations collected in Pemba Channel, a deep-water (800 m) channel separating Pemba Island from mainland Tanzania, during the South East monsoon indicate the presence of active upwelling along the western edge of Pemba Island. Surface salinity values, nutrient concentrations and the presence of coccolithophore species previously reported from the mid to lower euphotic zone all suggest upwelling from at least 80–100 m depth. The surface waters of the channel were characterised with low NO3−:PO43− (0.68:1) and NO3−:Si (0.04:1) ratios far below the Brzezinski-Redfield ratio indicating the presence of N-limitation and the possibility that these waters may be susceptible to anthropogenic N inputs. Surface NO3− concentrations averaged 0.09 ± 0.10 μmol L−1 but increased to 0.5 μmol L−1 in the centre of upwelling where coincidentally both integrated nutrient concentrations and surface POC/PON pools were approximately 2-fold higher than the channel average. Despite its significance for local productivity upwelling is tentatively estimated, via stoichiometric assumptions, to enhance local productivity by only 20%. The modest productivity response to upwelling may be explained by picoplankton (0.2–2 μm) dominance of the phytoplankton community with this size-class representing ~80% of total chlorophyll-a. Nevertheless, important spatial variability was identified in larger size fractions and supported by taxonomic analyses with indications that the distribution of Chaetoceros spp. alone may be particularly relevant for understanding the variability in larger (>20 μm) chlorophyll-a size fractions. The location of upwelling has previously been shown to host large concentrations of small pelagic fish thus management of this regionally important resource would benefit from additional investigation of the underlying physical mechanism driving upwelling and subsequently how trophic interactions and ecosystem productivity are influenced

Anisakid nematodes in Trichiurus lepturus and Saurida undosquamis (Teleostea) from the South-West Indian Ocean: Genetic evidence for the existence of sister species within Anisakis typica (s.l.), and food-safety considerations

Nematode parasites of the genus Anisakis (Nematoda, Anisakidae) are considered among the most important biological hazards in seafood products worldwide. In temperate and tropical waters, the most common species appears to be Anisakis typica, generally found around the viscera and sporadically in the flesh of various fish host species. This study investigated the infection sites and genetic diversity of A. typica infecting commercial fishes from the South-West Indian Ocean. Largehead hairtail (N = 20) and brushtooth lizardfish (N = 72) fished off Tanzania were inspected for anisakid nematodes by UV-press. A subsample of 168 nematodes were identified by sequence analyses of the cox2 mtDNA gene and ITS region of rDNA. The species A. typica (s.l.) (N = 166), Pseudoterranova ceticola (N = 1) and Anisakis paggiae (N = 1) were molecularly identified. Phylogenetic analysis of A. typica (s.l.) sequences based on both genes, indicated the existence of two distinct phylogenetic lineages forming two well-supported clades. The first clade comprised 12 A. typica specimens including individuals from its type locality (central Atlantic Ocean). The second clade comprising 154 specimens, clustered with reference sequences retrieved from GenBank including one apparently undescribed taxon, i.e., Anisakis sp. 1, and A. typica var. indonesiensis. The two reciprocally monophyletic clades are closely related and correspond to two distinct sister species within A. typica (s.l.), presently indicated as A. typica sp. A and A. typica sp. B. Two and four fixed alternative nucleotide substitutions (SNPs), i.e., diagnostic positions, between the two taxa, respectively, were found at the mtDNA cox2 and the ITS region of rDNA. The genetic data, as well as their occurrence in sympatry, strengthens the hypothesis that the actual specimens represent two distinct gene pools. The occurrence of both A. typica sp. A and A. typica sp. B in the musculature of freshly examined T. lepturus and S. undosquamis, suggests that both species can migrate intra-vitam into the flesh. Although the zoonotic potential of A. typica s.l. is still unclear, the presence of these parasites in the musculature, edible part of the fish, raises health concerns for consumers

The Need for Global Application of the Accountability for Reasonableness Approach to Support Sustainable Outcomes Comment on "Expanded HTA Enhancing Fairness and Legitimacy"

The accountability for reasonableness (AFR) concept has been developed and discussed for over two decades. Its interpretation has been studied in several ways partly guided by the specific settings and the researchers involved. This has again influenced the development of the concept, but not led to universal application. The potential use in health technology assessments (HTAs) has recently been identified by Daniels et al as yet another excellent justification for AFR-based process guidance that refers to both qualitative and a broader participatory input for HTA, but it has raised concerns from those who primarily support the consistency and objectivity of more quantitative and reproducible evidence. With reference to studies of AFR-based interventions and the through these repeatedly documented motivation for their consolidation, we argue that it can even be unethical not to take AFR conditions beyond their still mainly formative stage and test their application within routine health systems management for their expected support to more sustainable health improvements. The ever increasing evidence and technical expertise are necessary but at times contradictory and do not in isolation lead to optimally accountable, fair and sustainable solutions. Technical experts, politicians, managers, service providers, community members, and beneficiaries each have their own values, expertise and preferences, to be considered for necessary buy in and sustainability. Legitimacy, accountability and fairness do not come about without an inclusive and agreed process guidance that can reconcile differences of opinion and indeed differences in evidence to arrive at a by all understood, accepted, but not necessarily agreed compromise in a current context -until major premises for the decision change. AFR should be widely adopted in projects and services under close monitoring and frequent reviews

A systems perspective on the importance of global health strategy developments for accomplishing today's Sustainable Development Goals

Priority setting within health systems has not led to accountable, fair and sustainable solutions to improving population health. Providers, users and other stakeholders each have their own health and service priorities based on selected evidence, own values, expertise and preferences. Based on a historical account, this article analyses if contemporary health systems are appropriate to optimize population health within the framework of cross cutting targets of the Sustainable Development Goals (SDGs). We applied a scoping review approach to identify and review literature of scientific databases and other programmatic web and library-based documents on historical and contemporary health systems policies and strategies at the global level. Early literature supported the 1977 launching of the global target of Health for All by the year 2000. Reviewed literature was used to provide a historical overview of systems components of global health strategies through describing the conceptualizations of health determinants, user involvement and mechanisms of priority setting over time, and analysing the importance of historical developments on barriers and opportunities to accomplish the SDGs. Definitions, scope and application of health systems-associated priority setting fluctuated and main health determinants and user influence on global health systems and priority setting remained limited. In exploring reasons for the identified lack of SDG-associated health systems and priority setting processes, we discuss issues of accountability, vested interests, ethics and democratic legitimacy as conditional for future sustainability of population health. To accomplish the SDGs health systems must engage beyond their own sector boundary. New approaches to Health in All Policies and One Health may be conducive for scaling up more democratic and inclusive priority setting processes based on proper process guidelines from successful pilots. Sustainable development depends on population preferences supported by technical and managerial expertise

A systems perspective on the importance of global health strategy developments for accomplishing today’s Sustainable Development Goals

Priority setting within health systems has not led to accountable, fair and sustainable solutions to improving population health. Providers, users and other stakeholders each have their own health and service priorities based on selected evidence, own values, expertise and preferences. Based on a historical account, this article analyses if contemporary health systems are appropriate to optimize population health within the framework of cross cutting targets of the Sustainable Development Goals (SDGs). We applied a scoping review approach to identify and review literature of scientific databases and other programmatic web and library-based documents on historical and contemporary health systems policies and strategies at the global level. Early literature supported the 1977 launching of the global target of Health for All by the year 2000. Reviewed literature was used to provide a historical overview of systems components of global health strategies through describing the conceptualizations of health determinants, user involvement and mechanisms of priority setting over time, and analysing the importance of historical developments on barriers and opportunities to accomplish the SDGs. Definitions, scope and application of health systems-associated priority setting fluctuated and main health determinants and user influence on global health systems and priority setting remained limited. In exploring reasons for the identified lack of SDG-associated health systems and priority setting processes, we discuss issues of accountability, vested interests, ethics and democratic legitimacy as conditional for future sustainability of population health. To accomplish the SDGs health systems must engage beyond their own sector boundary. New approaches to Health in All Policies and One Health may be conducive for scaling up more democratic and inclusive priority setting processes based on proper process guidelines from successful pilots. Sustainable development depends on population preferences supported by technical and managerial expertise