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dc.contributor.authorGhorbel, M.
dc.contributor.authorOuld Yarba, L.
dc.contributor.authorBouain, A.
dc.coverage.spatialMauritanian coastsen
dc.date.accessioned2006-03-13T21:44:59Z
dc.date.available2006-03-13T21:44:59Z
dc.date.issued2004
dc.identifier.citationBull. INSTM Salammbô, 31, p. 35-42en
dc.identifier.issn0330-0080
dc.identifier.urihttp://hdl.handle.net/1834/1165
dc.description.abstractAge and growth of <Pagellus bellottii> (Sparidae) of Mauritanian coasts : The red Pandora <Pagellus bellottii> is one of the most important demersal species in the fisheries of Mauritanian coasts. Several gears and fleet traditionally exploit it. The studies concerning this fish and particularly those of its age and growth are rare and haven’t used the adequate method, which founded on hard pieces like scale and vertebra. The objective of the present work is to contribute to the knowledge of the growth parameters of the red Pandora using the scales method not yet used in the studied area. To determine the age and to study the growth of <Pagellus bellottii> in Mauritanian coasts, we have used the scales of 544 individuals. We have token, 8 scales under the fin pectoral and we have read the age using a binocular magnifying glass provided with an ocular micrometer. The ray of scale (R) and the rays of different slowing down of growth ring are raised along a centerline. For the determination of number of slowing down of growth rings annually formed and to determine their appearance period, we have analyzed the monthly variations of marginal lengthening (AM). To study the linear growth, we have established the relations binding size (FL) and total ray of the scale (R). Using the software “FSAS” based on the nonlinear adaptation of Maquardt, we have arranged the growth curve and determined the linear growth parameters of the Von Bertalanffy model. To check the obtained results, we have used the method of Ben Salem and Daget. Finally we have described mass growth, by the Von Bertalanffy equation, which expresses the mass evolution depending on the time. The study of age and growth of <Pagellus bellottii> of the Mauritanian coasts by the scalimetry method showed a minimal value of marginal lengthening in December for males and females. The graphic representation of marginal lengthening showed two principal decreases: the first in June-July coincides with the period of spawning; the second in December correspond to slowing down of growth ring. The estimate of the age using the slowing down of growth rings, allows distinguishing 8 age groups for males and 7 age groups for females The values of theorical length obtained by the Von Bertalanffy equation were nearly similar to those calculated by retrocalcul. We announce consequently that the model of Von Bertalanffy applies perfectly to the growth of <Pagellus bellottii> in Mauritanian coasts. The linear growth is practically the same for the two sexes while the mass growth is in favor of the males.en
dc.description.abstractتمت دراسة نمو سمك المرجان<Pagellus bellottii> بالسواحل الموريتانية اعتمادا على الحراشف. في بداية هذه الدراسة تبين أن فترة توقف النمو عند هذا النوع من السمك توافق شهر ديسمبر بواسطة الحساب الرجعي، حددنا الطول (LF) عند ظهور كل حلقة توقف النمو. مكن تطبيق النموذج الحسابي لVon Bertalanffy على هذه الأطوال من تحديد ثوابت النمو بالطول والوزن عند هذا السمك لكل جنس على حدة واتضح أن هذا النموذج ينطبق جيدا على نمو هذا السمك نظرا لتقارب الأطوال المحسوبة والأطوال المقدرة نظريا.ar
dc.description.abstractL’étude de l’âge et de la croissance de <Pagellus bellottii> des côtes mauritaniennes par la lecture des écailles (scalimétrie) montre que la valeur minimale de l’allongement marginal est enregistrée au mois de décembre pour les mâles et les femelles. L’examen des représentations graphiques de l’allongement marginal montre deux principales chutes : une chute en juin-juillet qui coïncide avec la période de ponte, une deuxième chute apparaît en décembre et correspond à la formation de l’anneau de ralentissement de la croissance. Les paramètres de la croissance linéaire L , K et t0 relatifs à l’équation de Von Bertalanffy ont été calculés à partir de deux méthodes basées sur des itérations. Une courbe de Von Bertalanffy a été ajustée aux données observées. Les valeurs des longueurs théoriques calculées à partir de l’équation de Von Bertalanffy sont très proches ou égales à celles déterminées par le rétrocalcul, aussi bien chez les mâles que chez les femelles. Concernant la croissance massique, nous avons établi d’une part les relations taille-masse et d’autre part, les relations masse-âge. Ces dernières ont été déduites de l’équation du modèle de Von Bertalanffy.fr
dc.format.extent299104 bytes
dc.format.mimetypeapplication/pdf
dc.language.isofren
dc.publisherINSTMen
dc.subject.classificationPagellus bellottiien
dc.subject.otherScalimétrie
dc.subject.otherCroissance
dc.subject.otherSparidae
dc.titleAge et croissance de <Pagellus bellottii> (sparidae) des côtes Mauritaniennes.fr
dc.title.alternativeAge and growth of <Pagellus bellottii> (Sparidae) of Mauritanian coastsen
dc.typeJournal Contribution
dc.bibliographicCitation.endpage42en
dc.bibliographicCitation.stpage35en
dc.bibliographicCitation.titleBull. INSTM Salammbôfr
dc.bibliographicCitation.volume31en
dc.description.statusPublisheden
dc.subject.agrovocGrowthen
dc.subject.agrovocAgeen
dc.subject.asfaAgeen
dc.subject.asfaGrowthen
dc.subject.asfaDemersal fisheriesen
dc.type.refereedRefereeden
dc.type.specifiedArticleen
refterms.dateFOA2021-01-30T18:47:46Z


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  • Articles - Bulletin [746]
    Le Bulletin de l'INSTM est publié depuis 1924. Il est indexé dans ASFA. Il fait suite au Bull. INSTOP et au Bull. SOS.
  • AfReMaS [433]
    African Register of Marine Species

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