Life cycle of a sea louse, Caligus elongatus von Nordmann, 1832 (Copepoda, Siphonostomatoida, Caligidae)
Caligus elongatus, known as a sea louse, is a very important pathogen of sea-farmed Atlantic salmon (Salmo salar). The life cycle of C. elongatus was examined under laboratory conditions. The observations were made at 10 °C, with ambient photoperiod. Small Arctic char (Salvelinus alpinus) kept in fu...
| Published in: | Canadian Journal of Zoology |
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| Main Authors: | , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Canadian Science Publishing
1995
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| Subjects: | |
| Online Access: | http://dx.doi.org/10.1139/z95-009 http://www.nrcresearchpress.com/doi/pdf/10.1139/z95-009 |
| Summary: | Caligus elongatus, known as a sea louse, is a very important pathogen of sea-farmed Atlantic salmon (Salmo salar). The life cycle of C. elongatus was examined under laboratory conditions. The observations were made at 10 °C, with ambient photoperiod. Small Arctic char (Salvelinus alpinus) kept in full-salinity seawater were used as experimental host fish. They were infected individually by offspring of several C. elongatus females. The hosts were killed at consecutive time periods after infection and developmental stages of the parasite were recovered. The life cycle consists of 8 stages: 2 nauplii, 1 copepodid, 4 chalimi, and adult. A separate preadult stage does not occur. The copepodid is infective and all subsequent stages live on fish. The time at which a particular stage is attained by 50% of individuals in a cohort (T 50 ) was as follows: chalimus I, 7.1 days post infection (dpi); chalimus II, 11.4 dpi; chalimus III, 14.0 dpi; chalimus IV, 17.6 dpi; adult, 24.7 dpi. The generation time was 43.3 days. The females can lay eggs at least twice. The males die after copulation (38–54 days after hatching). Overwintering females show signs of diapause. |
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