Seasonal changes in blood cells of Arctic char (Salvelinus alpinus L.) from a high mountain lake

Abstract

Seasonal changes in blood erythrocytes and lymphocytes were investigated in Arctic char from a remote high mountain lake at an altitude of 2344 m. Despite striking seasonal differences of environmental conditions the erythrocyte numbers remained constant during the year. Lymphocytes, however, displayed a distinct seasonal pattern with low abundance during the period of ice-cover (about 7 months) and high abundance in summer. During winter the circulating blood contained lymphocytes with damaged organelles and membranes, and almost exclusively mature red cells with a high density. With rising water temperature in July/August (11°C), however, high-density (old) cells almost disappeared, the proportion of immature cells dramatically increased, and the capacity to responding to handling stress decreased. We conclude that in summer the accelerated erythropoiesis (recruitment of red blood cells) compensates for the reduced life span of red blood cells.

Daily and seasonal variations in haematological and blood biochemical parameters in the tench, Tinca tinca Linnaeus, 1758

“…This result was expected and it is in accordance with previous data in tench (Habekovic 1991; Svobodová, Flajshans, Kolárová, Modra, Svoboda & Vajcová 2001). The daily rhythm in total leucocyte counts was clearly different in spring and winter, supporting that immune responses in tench vary seasonally (Guijarro, López‐Patiño, Pinillos, Isorna, De Pedro, Alonso‐Gómez, Alonso‐Bedate & Delgado 2003), as has been documented for other lower vertebrates (Zapata, Varas & Torroba 1992; Hofer et al 2000). Different zeitgebers (photoperiod, temperature changes and feeding) can entrain these leucocytes rhythms.…”

“…Several factors can influence blood parameters in fish, such as species and strain (Langston, Hoare, Stefansson, Fitzgerald, Wergeland & Mulcahy 2002), temperature (Langston et al 2002; Magill & Sayer 2004), age (Svetina, Matasin, Tofant, Vucemilo & Fijan 2002), stress (Hofer, Stoll, Romani, Koch & Sordyl 2000; Leonardi & Klempau 2003; Cnaani, Tinman, Avidar, Ron & Hulata 2004; Silverira‐Coffigny et al 2004; Morales, Cardenete, Abellán & García‐Rejón 2005), photoperiod (Leonardi & Klempau 2003), nutritional state (Svetina et al 2002; Lim & Klesius 2003) and methodology used to determine these parameters (Huffman et al 1997). Thus, the establishment of reliable reference values under defined environmental conditions is a prerequisite before haematology and blood biochemistry can be used for determining biomarkers of disease and/or pollutant exposure (Handy & Depledge 1999).…”

Anesthesia of wild female Persian sturgeon,Acipenser persicus(Borodin, 1897) breeders during controlled propagation: effects on hematological parameters, stress response and reproductive performance

“…Although hematological studies appear to be worthwhile preclinical tests that reflect the physiological and health Effect of anesthesia on sturgeon breeders 999 status of the fish (Shahsavani et al, 2010), many intrinsic and extrinsic factors affect the hematological parameters, such as the season, temperature, water quality, age, stage of development, sex, maturity, photoperiod, health condition, stress (capture, transporting, handling, etc. ), as well as the nutritional state (Blaxhall, 1972;Hrubec et al, 1996Hrubec et al, , 1997Hofer et al, 2000;Leonardi and Klempau, 2003). Therefore, it is difficult to determine a clear reference value for blood parameters, especially in wild fish, as their environmental history is not known.…”

Seasonal changes of the gill epithelia of Arctic char (Salvelinus alpinus) from a high mountain lake

“…The major stress hormone cortisol, when injected in trout, was shown to increase the fractional area of chloride cells and leads to a thickening of the blood-to-water barrier which impairs branchial gas transfer and accelerates gill ventilation (Goss et al, 1994;Bindon et al, 1994;Greco et al, 1995;Perry et al, 1996). In fact, during summer Arctic char from OPL show some signs of stress: blood analyses in OPL fish revealed an abnormally high proportion of immature cells while the total number of red blood cells remained low (Hofer et al, 2000). This indicates an accelerated erythrocyte turnover which is compensated by a high rate of erythropoiesis.…”

“…This indicates an accelerated erythrocyte turnover which is compensated by a high rate of erythropoiesis. Furthermore, the ability to mobilize additional cells from storage organs when exposed to acute handling stress is reduced during mid-summer (Hofer et al, 2000). During summer, fish of OPL displayed also distinct signs of oxidative stress (increased concentrations of glutathione disulphide in the liver as a result of the detoxification of radicals) and reduced liver glycogen (Lackner, personal communication).…”