Biological parameters and parasite loads of eel populations (Anguilla anguilla l.) inhabiting two water bodies in coastal Algeria

• Main Authors: Djouahra, Chafika, ARAB, Abdeslem
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2017
• Subjects: envir; geo; Tonga; Anguilla anguilla
• Online Access: https://hal.archives-ouvertes.fr/hal-03532877/file/bitstream_122946.pdf; https://hal.archives-ouvertes.fr/hal-03532877

International audience Analysis of the spatiotemporal variation of the biological parameters of European eels (Anguilla anguilla) inhabiting two aquatic systems in coastal Algeria revealed no significant differences in length, gonadosomatic index, hepatosomatic index, or condition coefficient between non-parasitized (NPT) and parasitized (with the nematode Anguillicoloides crassus) (PT) sub-populations at Lake Tonga. However, there were significant differences in these parameters between the two Lake Tonga sub-populations and a non-parasitized population at Bou Haroun port (NPT). There were no significant differences in weight among these three sub-populations. The highest values of the condition coefficient were observed in eels at Lake Tonga. Parasite numbers ≥10 per swim bladder had a negative effect on all measured biological parameters. At both stations, the condition of the eels was lowest in the spring and summer. Principal components analysis distinguished two groups of eels. The first comprised the Lake Tonga individuals, separated by parasitic indices and dissolved oxygen. The second group comprised the Bou Haroun eels, separated by pollution parameters. In fact this parasite was not present at Bou Haroun, presumably because it is unable to develop in this environment. Both Anguillicoloides crassus and Anguilla anguilla, prefer non-polluted environments with low salinity, as found in Lake Tonga. L’évolution spatio-temporelle des paramètres biologiques (Lt, GSI, HSI, kc) des anguilles européennes, peuplant deux hydrosystèmes différents du littoral algérien, montre qu’il n’y a aucune différence significative de ces paramètres entre deux sous-populations d’anguille du lac Tonga, l’une parasitée (PT) et l’autre non parasitée (NPT) par le Nématode Anguillicoloides crassus mais nous notons une différence significative entre ces deux sous-populations d’anguilles du lac Tonga et la sous-population d’anguilles non parasitée (NPT) du port de Bou Haroun, sauf pour le poids total (Wt). Les valeurs les plus ...