Highly migratory, cosmopolitan oceanic sharks often exhibit complex movement patterns influenced by ontogeny, reproduction, and feeding. These elusive species are particularly challenging to population genetic studies, as representative samples suitable for inferring genetic structure are difficult to obtain. Our study provides insights into the genetic population structure one of the most abundant and wide‐ranging oceanic shark species, the blue shark Prionace glauca, by sampling the least mobile component of the populations, i.e., young‐of‐year and small juveniles (<2 year; N = 348 individuals), at three reported nursery areas, namely, western Iberia, Azores, and South Africa. Samples were collected in two different time periods (2002–2008 and 2012–2015) and were screened at 12 nuclear microsatellites and at a 899‐bp fragment of the mitochondrial control region. Our results show temporally stable genetic homogeneity among the three Atlantic nurseries at both nuclear and mitochondrial markers, suggesting basin‐wide panmixia. In addition, comparison of mtDNA CR sequences from Atlantic and Indo‐Pacific locations also indicated genetic homogeneity and unrestricted female‐mediated gene flow between ocean basins. These results are discussed in light of the species' life history and ecology, but suggest that blue shark populations may be connected by gene flow at the global scale. The implications of the present findings to the management of this important fisheries resource are also discussed.
The blue shark (Prionace glauca) is the most frequently captured shark in pelagic oceanic fisheries, especially pelagic longlines targeting swordfish and/or tunas. As part of cooperative scientific efforts for fisheries and biological data collection, information from fishery observers, scientific projects and surveys, and from recreational fisheries from several nations in the Atlantic and Indian Oceans was compiled. Data sets included information on location, size and sex, in a total of 478,220 blue shark records collected between 1966 and 2014. Sizes ranged from 36 to 394 cm fork length.Considerable variability was observed in the size distribution by region and season in both oceans. Larger blue sharks tend to occur in equatorial and tropical regions, and
The common smooth-hound (Mustelus mustelus) is the topmost bio-economically and recreationally important shark species in southern Africa, western Africa, and Mediterranean Sea. Here, we used the Illumina HiSeq™ 2000 next-generation sequencing (NGS) technology to develop novel microsatellite markers for Mustelus mustelus. Two microsatellite multiplex panels were constructed from 11 polymorphic loci and characterized in two populations of Mustelus mustelus representative of its South African distribution. The markers were then tested for cross-species utility in Galeorhinus galeus, Mustelus palumbes, and Triakis megalopterus, three other demersal coastal sharks also subjected to recreational and/or commercial fishery pressures in South Africa. We assessed genetic diversity (N A , A R , H O , H E, and PIC) and differentiation (F ST and D est ) for each species and also examined the potential use of these markers in species assignment. In each of the four species, all 11 microsatellites were variable with up to a mean N A of 8, A R up to 7.5, H E and PIC as high as 0.842. We were able to reject genetic homogeneity for all species investigated here except for T. megalopterus. We found that the panel of the microsatellite markers developed in this study could discriminate between the study species, particularly for those that are morphologically very similar. Our study provides molecular tools to address ecological and evolutionary questions vital to the conservation and management of these locally and globally exploited shark species.
K E Y W O R D Scross-amplification, Galeorhinus galeus, Illumina sequencing, microsatellites, Mustelus mustelus,
Mustelus palumbes, Triakis megalopterus
| INTRODUCTIONSharks play a crucial role in maintaining the ecological balance in marine ecosystems as keystone species, yet these animals are gradually declining worldwide in seascapes heavily impacted by humans (Dulvy et al., 2014). Such declines in wild populations not only will have negative ecological impacts on lower trophic species (Price, O'Bryhim, Jones, & Lance, 2015) but can also alter the levels and distribution of | 1463genetic diversity among populations (Dudgeon et al., 2012). It is likely that sharks may not respond well to population declines compared to other marine fishes owing to their K-selected life-history traits, i.e., slow growth, late maturity, and low reproductive outputs (Compagno, 1984;Ebert, Fowler, Compagno, & Dando, 2013). This highlights the need for conservation and management measures to ensure the sustainable utilization of these fishery resources. Implementing such measures often requires information on fishery dynamics, biological and baseline ecological data which in most cases are not yet available (Velez-Zuazo, Alfaro-Shigueto, Mangel, Papa, & Agnarsson, 2015).Molecular approaches have been very useful in providing insight into historical and contemporary demography of various commercially important shark species, especially with respect to population connectivity, stock structure, and m...
The tope shark (Galeorhinus galeus Linnaeus, 1758) is a temperate, coastal hound shark found in the Atlantic and Indo-Pacific oceans. In this study, the population structure of Galeorhinus galeus was determined across the entire Southern Hemisphere, where the species is heavily targeted by commercial fisheries, as well as locally, along the South African coastline. Analysis was conducted on a total of 185 samples using 19 microsatellite markers and a 671 bp fragment of the NADH dehydrogenase subunit 2 (ND2) gene. Across the Southern Hemisphere, three geographically distinct clades were recovered, including one from South America (Argentina, Chile), one from Africa (all the South African collections) and an Australia-New Zealand clade. Nuclear data revealed significant population subdivisions (FST = 0.192 to 0.376, p<0.05) indicating limited gene flow for tope sharks across ocean basins. Marked population connectivity was however evident across the Indian Ocean based on Bayesian clustering analysis. More locally in South Africa, F-statistics and multivariate analysis supported moderate to high gene flow across the Atlantic/Indian Ocean boundary (FST = 0.035 to 0.044, p<0.05), with exception of samples from Struisbaai and Port Elizabeth which differed significantly from the rest. Discriminant and Bayesian clustering analysis indicated admixture in all sampling populations, decreasing from west to east, corroborating possible restriction to gene flow across regional oceanographic barriers. Mitochondrial sequence data recovered seven haplotypes (h = 0.216, π = 0.001) for South Africa, with one major haplotype shared by 87% of the individuals and at least one private haplotype for each sampling location except Port Elizabeth. As with many other coastal shark species with cosmopolitan distribution, this study confirms the lack of both historical dispersal and inter-oceanic gene flow while also implicating contemporary factors such as oceanic currents and thermal fronts to drive local genetic structure of G. galeus on a smaller spatial scale.
Objetivou-se identificar o conhecimento dos enfermeiros quanto à prática do brincar e do Brinquedo Terapêutico na hospitalização da criança. Estudo descritivo com abordagem qualitativa, realizado com 10 enfermeiros que atuam em um hospital público infantil no Norte de Santa Catarina, por meio de uma entrevista semiestruturada, no ano de 2018. Os dados foram analisados conforme o método da análise temática. Emergiram quatro categorias temáticas: o brincar e o enfermeiro; o brincar como parte do tratamento; o brincar em um ambiente favorável; a abordagem do enfermeiro e o uso do brinquedo/Brinquedo Terapêutico. Os resultados mostram que os enfermeiros reconhecem a importância do brincar durante a hospitalização da criança, considerado uma forma de aproximação com o infante. Verifica-se também o desconhecimento dos enfermeiros em relação à tecnologia do uso do Brinquedo Terapêutico durante a hospitalização como uma ferramenta de cuidados da enfermagem. Ressalta-se a importância da abordagem deste conteúdo nos cursos de graduação em enfermagem, especialização e residência em enfermagem pediátrica e a realização de cursos de capacitação para os profissionais da prática assistencial.
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