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Shinn, A.P.; Banks, B.A.; Tange, N.; Bron, J.E.; Sommerville, C.; Aoki, T.; Wootten, R.. |
Genetic differentiation within the salmon louse Lepeophtheirus salmonis (Krøyer, 1837), was investigated by the sequencing of specific nucleotide regions. Partial sequences of the 18S ribosomal RNA gene and the ribosomal internal transcribed spacer (ITS-1) region from single sea lice were amplified by the polymerase chain reaction (PCR). Lice were collected from wild and farmed Atlantic salmon ( Salmo salar L., 1758) from nine selected localities around the Scottish coastline. A 0.9kb fragment of the 18S ribosomal RNA gene was amplified and compared for several samples of lice which showed no observable differences between the lice from different collection sites confirming the absence of cryptic species. The 454 nucleotide ITS-1 sequence showed... |
Tipo: Article / Letter to the editor |
Palavras-chave: Sea louse; Copepod; Crustacea; Atlantic salmon; Sequencing; 18S ribosomal DNA; Internal transcribed spacer; Population genetics. |
Ano: 2000 |
URL: http://www.repository.naturalis.nl/record/534343 |
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Bron, J.E.; Shinn, A.P.; Sommerville, C.. |
The ultrastructure of moulting in the chalimus phase of the parasitic caligid copepod Lepeophtheirus salmonis is described for the first time. The major features of the moult sequence correspond to those of other Crustacea, save for the absence of a distinguishable intermoult as defined by reduced epidermal activity and a cessation of cuticle production. This latter may be explained cither in terms of a continuous moulting process related to the constant food supply available to a parasite or in terms of a highly abbreviated intermoult period. The findings are discussed with respect to studies of other Crustacean species. |
Tipo: Article / Letter to the editor |
Palavras-chave: Chalimus; Copepoda; Moult; Cuticle; Ultrastructure; Parasite. |
Ano: 2000 |
URL: http://www.repository.naturalis.nl/record/534408 |
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Shinn, A.P.; Bron, J.E.; Gray, D.J.; Sommerville, C.. |
Conventional nebulisation ICPMS (Inductively Coupled Plasma Mass Spectrometry), was used to determine the concentration of a broad range of elements in the salmon louse Lepeophtheirus salmonis. Lice samples were collected from Atlantic salmon in seven localities (4 fish farms and 3 wild salmon fisheries) on two separate sampling occasions and prepared for analysis. Sixty six elements were measured, 35 of these were found to be variable and were subjected to univariate and multivariate statistical analysis. The results of the single element comparisons showed that not all individual sites could be discriminated from each other. Sea lice collected from cultured salmonids could be discriminated from those on wild salmonids at the same site using the elements... |
Tipo: Article / Letter to the editor |
Palavras-chave: Elemental analysis; Sea lice; Crustacea; Copepoda. |
Ano: 2000 |
URL: http://www.repository.naturalis.nl/record/534401 |
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