6,939 research outputs found
The biological diversity and aquaculture of clariid and pangasiid catfishes in South-East Asia : proceedings of the mid-term workshop of the "Catfish Asia project"
No full textCatfishes, and in particular #Clariidae and #Pangasiidae, are important aquatic resources in Asia, where their culture represented an annual production of about 124,000 t in 1993. In the clariids, this production results mostly from the use of F1 hybrids between the introduced African catfish (#Claris gariepinus) and various local clariid species. In the pangasiids, various culturing techniques were empirically developed for some native species, whose juveniles are most often captured in the wild. Further development of this catfish culture industry faces serious problems related to the poorly known systematic of these fish groups, the scarce knowledge of the biology and aquaculture potential of autochthonous species, the limitation of seed supply and the declining performances reported in some cultivated stocks. In this context, the "Catfish Asia" project which deals with the two catfish families, #Clariidae and #Pangasiidae$, has the main following goals : to acquire a stronger knowledge of the biological diversity of SE Asian catfishes and to enhance its utilisation through a correct identification and characterisation of valuable species, populations and strains of aquaculture interest. This approach represents an important precondition to the sustainable management of cultivated and natural stocks and to guide conservation efforts of these economically important resources. It will also contribute to a better knowledge of their phylogeographic relationships ; to acquire sound biological bases for the development of catfish culture in the SE Asian region. The evaluation of the aquaculture potential of the autochthonous species (diversification) and the optimisation of their rearing cycle (artificial propagation) through technologies adapted to the local conditions are essential elements for a better production in the future... (D'après résumé d'auteur
The Future of Canadian Climate Policy — with Marc Lee
No full textMarc Lee is a Senior Economist at the Canadian Centre for Policy Alternatives\u27 BC Office. In addition to tracking federal and provincial budgets and economic trends, Marc has published on a range of topics from poverty and inequality to globalization and international trade to public services and regulation. Marc is the Co-Director of the Climate Justice Project, a research partnership with UBC\u27s School of Community and Regional Planning that examines the links between climate change policies and social justice.Resources:Climate Justice Project: www.policyalternatives.ca/projects/cli…tice-projectMarc Lee\u27s Posts on Policy Note: www.policynote.ca/author/marclee/Canadian Centre for Policy Alternatives: www.policyalternatives.ca/Marc\u27s Twitter: twitter.com/MarcLeeCCPA International Panel on Climate Change, 2021 report: www.ipcc.ch/report/ar6/wg1
Climate Justice & Inequality: The Future of Canadian Climate Policy — with Marc Lee
No full textMarc Lee is a Senior Economist at the Canadian Centre for Policy Alternatives\u27 BC Office. In addition to tracking federal and provincial budgets and economic trends, Marc has published on a range of topics from poverty and inequality to globalization and international trade to public services and regulation. Marc is the Co-Director of the Climate Justice Project, a research partnership with UBC\u27s School of Community and Regional Planning that examines the links between climate change policies and social justice.Resources: Climate Justice Project: https://www.policyalternatives.ca/projects/climate-justice-projectMarc Lee\u27s Posts on Policy Note: https://www.policynote.ca/author/marclee/Canadian Centre for Policy Alternatives: https://www.policyalternatives.ca/Marc\u27s Twitter: https://twitter.com/MarcLeeCCPA International Panel on Climate Change, 2021 report: https://www.ipcc.ch/report/ar6/wg1
The biological diversity and aquaculture of clariid and pangasiid catfishes in South-East Asia : proceedings of the mid-term workshop of the "Catfish Asia project"
No full textWith the aim of detecting phylogenetic relationships among #Pangasiidae catfishes, 23 enzyme loci were studied on 18 nominal species of the genera #Pangasius and #Helicophagus (Roberts and Vidthayanon, 1991). In order to assess the taxonomic position of #Laides genus in the #Schilbeidae or in the #Pangasiidae, 2 species belonging to the genus #Laides and 1 species of the genus #Pseudeutropius (#Siluriformes, #Schilbeidae) were added in the study. The results indicate that the species #Laides hexanema and #Laides sinensis appear to be genetically related with the #Pangasiidae. The phylogenetic tree obtained shows a clustering of species which validate the genus #Helicophagus but indicates that the genus #Pangasius is polyphyletic. The genus #Pangasius is composed of 3 genetic differentiated groups. Group 1 is composed of 3 species belonging to two different morphological entities validated by Roberts and Vidthayanon (1991) as possible subgenus. #Pangasius hypophthalmus and #P. gigas which share common genetic characters validate the subenus #Pangasianodon. The possession of many private alleles by #P. pleurotaenia confirms the morphological originality of this species which was therefore considered to belong to the monotypic subgenus #Pteropangasius. The second groupd consists of #P. micronema, #P. macronema, #P. lithostoma and #P. polyuranodon and the last group represents all the other species of the genus #Pangasius. By contrast #Neopangasius considered as a possible subgenus by Roberts and Bidthayanon (1991) is polyphyletic. Although relative genetic similarities were found between #P. humeralis and #P. nieuwenhuisii which are located in group 3, the species #P. lithostoma appears to be more closely related to species belonging to the group 2... (D'après résumé d'auteur
The biological diversity and aquaculture of clariid and Pangasiid catfishes in South-East Asia : proceedings of the mid-term workshop of the "Catfish Asia project"
No full textAn evaluation of the seasonal variations of sexual activity of #P. hypophthalmus broodstock held in 50 m2 ponds was carried out between April 1997 and April 1998 at the Sukamandi station (West Java, 6°S of latitude). These variations were assessed through the evolution of oocyte diameter of individual females, the proportion of fluent males and the success of hormonal-induced breeding trials. High proportions of fluent males and mature females with post-vitellogenic oocytes of modal diameter superior to 1.00 mm were found at anytime. As a consequence, successful induced breeding of this species using hormonal treatments could be performed regardless of season and allowed an all year long production of fry. This continuous sexual maturity of #P. hypophthalmus broodstock, during both the dry and rainy seasons, may have resulted to a large extent from rather stable conditions, with a monthly mean water temperature constantly high (28-31°C) and a low variation of day length during the year. Ovulation was successfully induced at 3, 2 and 4 months interval in a same #P. hypophthalmus$ female. This indicated a quick recovery of oogenesis in females reared in the ponds. (Résumé d'auteur
The biological diversity and aquaculture of Clariid and Pangasiid catfishes in South-East Asia : proceedings of the mid-term workshop of the "Catfish Asia project"
No full textA morphometric analysis of wild and cultured #Clarias specimens originating from Vietnam indicated the presence of three species : #C. batrachus, #C. macrocephalus and #C. gariepinus. The latter is an African species that has been introduced for fish culture purposes. The status of a fourth species, #C. fuscus$, previously reported from the northern part of the country, could not be clarified yet as no material could be examined. This is the subject of forthcoming research. (Résumé d'auteur
Souvenir de Miguel de Unamuno (1936-1986): inédits épistolaires et iconographiques relatifs à ses liens avec Maurice Legendre et la Casa de Velázquez
No full textDelaunay Jean-Marc. Souvenir de Miguel de Unamuno (1936-1986): inédits épistolaires et iconographiques relatifs à ses liens avec Maurice Legendre et la Casa de Velázquez. In: Mélanges de la Casa de Velázquez, tome 22, 1986. pp. 401-418
The biological diversity and aquaculture of clariid and pangasiid catfishes in South-East Asia : proceedings of the mid-term workshop of the "Catfish Asia project"
No full textAs part of an ongoing systematic revision of the South-East Asian #Clarias species, this paper presents the results of a morphometric study of 317 specimens from Indonesia : 255 of them who collected from the wild in Sumatra and Kalimantan and 62 came from fish culture stations in Java and Sumatra. The results obtained indicated the presence of five or six species : #Clarias batrachus, #C. macrocephalus (?), #C. meladerma, #C.leiacanthus, #C. teijsmanni and #C. nieuhofii$. Preliminary identification characters are given. (Résumé d'auteur
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