Wyniki wyszukiwania

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Histological structure of the skin of Arctic charr, Salvelinus alpinus [L.] from Spitsbergen

100%

Witkowski A., Kaleta K., Kuryszko J., Kusznierz J.

Acta Ichthyologica et Piscatoria

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2004

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tom 34

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nr 2

Background. Like in most salmonids, females of Artic charr dig nests, while spawning, to deposit their eggs, while the role of males is most often limited to the territorial defence. The aim of this study was to examine the histological structure of skin in both sexes, in the body parts which are particularly exposed to mechanical damage during spawning. Materials and Methods. Based on material representing three forms (anadromous, land-locked (lake), and dwarf/riverine), collected in the pre-spawning and spawning periods, histological structure of the skin was analysed for three body areas: dorsum (back), side, and venter (belly). Results. In females of all the forms the skin in analysed body areas was thicker and contained more mucous cells, compared to males. In the ventral region it was the thickest, on the dorsum-the thinnest. A comparison of the skin structure in the three forms showed that, in the land-locked form (both sexes), the skin in all the body parts was thicker and richer in mucous cells, compared to the anadromous form. Conclusion. The skin of Arctic charr females plays a protective role, preventing mechanical damage during nest digging and egg burying, because of its substantial thickness and the abundance of mucous cells especially in the ventral region.

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Carotenoid content in various body parts of Atlantic salmon [Salmo salar L.] and Arctic charr [Salvelinus alpinus L.] specimens from an ocean ranching farm

100%

Czeczuga B., Czeczuga-Semeniuk E., Tryggvadottir S. V.

Oceanological and Hydrobiological Studies

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2005

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tom 34

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nr Suppl.1

3

Interspecific differences between Atlantic salmon and Arctic charr in susceptibility to infection with larval and adult Caligus elongatus: effect of skin mucus protein profiles and epidermal histological differences

80%

Mustafa A., Mackinnon B. M., Piasecki W.

Acta Ichthyologica et Piscatoria

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2005

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tom 35

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nr 1

Background. Arctic charr, Salvelinus alpinus (L.), are known to harbour significantly more sea lice, Caligus elongatus von Nordmann, 1832, than do Atlantic salmon, Salmo salar L. This research investigated whether this is due to differences in initial infection or to resettlement/loss of mobile adults. Skin mucus protein profiles and epidermal histology were also studied as two characteristics that might help explain interspecific differences in host susceptibility. Materials and Methods. Atlantic salmon and Arctic charr were sampled from the sea-pen after 12 weeks of exposure to natural infection. Fishes were examined for sea lice counts and mucus was analysed for protein profiles using standard methods of poly-acrylamide gel electrophoresis. Epidermal tissue of fishes around chalimus attachment sites was also examined by transmission electron microscopy. Results. Interspecific differences in host susceptibility were determined not to be due to differences in initial infection rate, as charr and salmon had similar numbers of attached chalimi. Adult parasites were significantly more numerous on charr as a result of resettlement of adults lost by other fishes in the area. Gel electrophoresis indicated that salmon had a greater abundance of skin mucus proteins than charr, particularly in the 30–42 and 67–94 kDa range. Ultrastructural analysis of epidermal tissue indicated that charr had more mucous cells and showed evidence of possible osmotic stress. Interspecific differences also existed in intercellular adhesion characteristics. Salmon and charr showed a similar absence of inflammation around chalimus attachment sites. Conclusion. Artic charr had a more intense infection with Caligus elongatus than did salmon corresponding to fewer potentially antagonistic proteins in the mucus. Perhaps also, the epidermis of charr provides more easily accessible food for the sea lice. Higher levels of stress in charr in sea water may also have predisposed them to higher sea lice infections.

Ograniczanie wyników

2 Acta Ichthyologica et Piscatoria

1 Oceanological and Hydrobiological Studies

1 Czeczuga B.

1 Czeczuga-Semeniuk E.

1 Kaleta K.

1 Kuryszko J.

1 Kusznierz J.

1 Mackinnon B. M.

1 Mustafa A.

1 Piasecki W.

1 Tryggvadottir S. V.

1 Witkowski A.

2 2005

1 2004

Histological structure of the skin of Arctic charr, Salvelinus alpinus [L.] from Spitsbergen

Carotenoid content in various body parts of Atlantic salmon [Salmo salar L.] and Arctic charr [Salvelinus alpinus L.] specimens from an ocean ranching farm

Interspecific differences between Atlantic salmon and Arctic charr in susceptibility to infection with larval and adult Caligus elongatus: effect of skin mucus protein profiles and epidermal histological differences