Histological structure of the skin of Arctic charr, Salvelinus alpinus (L.) from Spitsbergen

Abstract

. Histological structure of the skin of Arctic charr, Salvelinus alpinus (L.) from Spitsbergen. Acta Ichthyol. Piscat. 34 (3): 241-251.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. Material and methods. Based on material representing three forms (anadromous, landlocked (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.

Morphological differences in the skin of marble trout <i>Salmo marmoratus</i> and of brown trout <i>Salmo trutta</i>

“…In the present study on S. marmoratus and S. trutta, they were found only in the dermis, confirming a general characteristic of salmonid skin [20][21][22]. The absence of melanophores in epidermis has also been observed in other European freshwater fish -e.g.…”

“…Relative thickness in both species decreases with age. The measured values are similar to those for other salmonids [20][21][22][23][24], though direct comparison was not possible due to methodological differences or missing supplementary information. Among central European species, significantly thicker head skin epidermis is found in some cyprinids (Carassius carassius (L.) 240 µm, Cyprinus carpio (L.) 400 µm) or Lotidae (Lota lota (L.) 360 µm) [25] than in salmonids.…”

Epidermis structure in the brook trout (Salvelinus fontinalis) and its Arctic char (Salvelinus alpinus) hybrid

“…On the other hand, Stoklosowa (1966Stoklosowa ( , 1970) described a thin epidermis with just one layer of small epithelial cells in male sea-trout S. trutta trutta during the sexually active period. Witkowski et al (2004) described a similar situation for brook trout.…”

“…see brown trout Salmo trutta m. fario), and particularly so during the spawning season (e.g. brown trout) (Pickering 1977;Knoz et al 1990) and Arctic char (Witkowski et al 2004). On the other hand, Stoklosowa (1966Stoklosowa ( , 1970) described a thin epidermis with just one layer of small epithelial cells in male sea-trout S. trutta trutta during the sexually active period.…”

Skin structure studies and molecular identification of the Atlantic cod Gadus morhua L. of unique golden pigmentation from the Svalbard Bank

“…Skin samples (10 × 10 mm) were taken from five body sites: two above the lateral line (behind the 1st and 3rd dorsal fins), one from the lateral line, and two below the lateral line near the pectoral and anal fins and fixated for 48 h in a 4.0% formalin solution, dehydrated in ethanol, then embedded in paraffin. The 5 μm thick sections were prepared using RM 2165 microtome (Leica Microsystems GmbH., Germany) and stained with haematoxylin‐eosin‐Alcian blue (pH 2.5) (Witkowski et al., 2004). Slides were studied under an ECLIPSE TE 2000‐S microscope (Nikon Instruments Inc.) and a Nikon COOLPIX 5400 digital camera.…”