%0 Journal Article
%T Growth and reproductive properties of Tench, Tinca tinca Linnaeus, 1758 in Trasimeno Lake (Umbria, Italy) Croissance et param¨¨tres de reproduction de la tanche, Tinca tinca Linnaeus, 1758 du Lac Trasim¨¨ne (Ombrie, Italie)
%A Pompei L.
%A Franchi E.
%A Giannetto D.
%A Lorenzoni M.
%J Knowledge and Management of Aquatic Ecosystems
%D 2012
%I EDP Sciences
%R 10.1051/kmae/2012024
%X Growth and some reproductive properties of native Tinca tinca Linnaeus, 1758 from Trasimeno Lake were investigated during 2009 and 2010. The total sample of fish (510) was composed by 126 males, 221 females and 163 immature specimens. Total length (TL ¡À 0.1 cm) and weight (W ¡À 0.1 g) were recorded; age estimation was based on scalimetry and sex was determined by microscopic observation of the gonads. Age composition varied from 1+  to 11+ . The TL-W relationship was log 10W =   2.235 + 3.248log 10TL. Previous growth was determined with back-calculation from scale measurements using the Fraser-Lee method. Theoretical length growth was estimated with von Bertalanffy¡¯s model. Analysis of the gonadosomatic index (GSI) suggests that the reproductive period of the population took place from May to July. Sexual maturation occurred in both sexes at the second year of life. The mean diameter of eggs was 0.075 mm. The mean number of eggs produced by each female was 233 930 and increased with the size of the specimens. Though it is one of the most widespread and interested species in fishing in Italian waters, tench has not been widely studied; this research deepens some biological characteristics of this species that is strongly shrinking in Italy. La croissance et certains param¨¨tres de la reproduction de Tinca tinca Linn¨¦, 1758 du Lac Trasim¨¨ne ont ¨¦t¨¦ ¨¦tudi¨¦s au cours de 2009 et 2010. L¡¯¨¦chantillon total de poissons (510) se composait de 126 males, 221 femelles et 163 individus immatures. La longueur totale (TL ¡À 0,1 cm) et le poids (W ¡À 0,1 g) ont ¨¦t¨¦ enregistr¨¦s; l¡¯estimation de l¡¯age a ¨¦t¨¦ faite par scalim¨¦trie et le sexe a ¨¦t¨¦ d¨¦termin¨¦ par l¡¯observation microscopique des gonades. La composition en age variait de 1 +  ¨¤ 11 + . La relation TL-W ¨¦tait log 10W =   2,235 + 3,248log 10TL. La croissance a ¨¦t¨¦ d¨¦termin¨¦e par r¨¦tro-calcul ¨¤ partir de mesures sur les ¨¦cailles en utilisant la m¨¦thode de Fraser-Lee. La croissance en longueur th¨¦orique a ¨¦t¨¦ estim¨¦e avec le mod¨¨le de von Bertalanffy. L¡¯analyse de l¡¯indice gonadosomatique (GSI) sugg¨¨re que la p¨¦riode de reproduction de la population a lieu de mai ¨¤ juillet. La maturation sexuelle a eu lieu dans les deux sexes d¨¨s la deuxi¨¨me ann¨¦e de vie. Le diam¨¨tre moyen des  ufs ¨¦tait de 0,075 mm. Le nombre moyen d¡¯ ufs produits par chaque femelle ¨¦tait 233 930 et augmentait avec la taille des sp¨¦cimens. Bien qu¡¯elle soit l¡¯une des esp¨¨ces les plus r¨¦pandues et recherch¨¦es par la p¨ºche dans les eaux italiennes, la tanche n¡¯a pas ¨¦t¨¦ largement ¨¦tudi¨¦e; cette recherche approfondit certaines caract¨¦ristiques biologique
%K von Bertalanffy¡¯s parameters
%K back calculation
%K reproduction
%K fecundity
%K gonadosomatic index
%K param¨¨tres de von Bertalanffy
%K r¨¦tro-calcul
%K reproduction
%K f¨¦condit¨¦
%K indice gonadosomatique
%U http://dx.doi.org/10.1051/kmae/2012024