Some age related changes of adult rainbow trout, Salmo gairdneri Rich., peripheral erythrocytes separated by velocity sedimentation at unit gravity

Abstract

Velocity sedimentation at unit gravity separated peripheral erythrocytes of adult rainbow trout according to age and size. The cells located at the top of the gradient contained numerous polyribosomes, few mitochondria and an essentially electronlucent nucleus. The cells at the bottom of the gradient no longer contained these cytoplasmic organelles and had an essentially electron-dense nucleus. The middle of the gradient contained cells with either very few polyribosomes or cells devoid of this organelle.The length, width and mean corpuscular volume (MCV) ofthe average cell increased and the width to length ratio decreased progressively from the top of the gradient to the bottom.No statistical significance could be determined in the changes of the mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) although they appeared to follow theoretical projections.The use of haematocrit, red cell count, haemoglobin concentration, MCV, MCH and MCHC in assessing erythropoietic activity and the size and haemoglobin content of the maturing cell is discussed.

Rainbow trout (Oncorhynchus mykiss) shift the age composition of circulating red blood cells towards a younger cohort when exposed to thermal stress

“…A total of 42,845 cells were counted (*1,000 cells per treatment/sample). Morphological characteristics of the fish blood cells were based on prior descriptions (Zexia et al 2007;Rothmann et al 2000;Lane et al 1982;Keen et al 1989). Juvenile cells were visually discriminated from mature cells by taking into consideration: (1) cell roundness, and (2) differential staining of the cell plasma (i.e.…”

Hematological response in fish: pronephric and splenic involvements in the goldfish,Carassius auratus L.

“…There is evidence that 02 transport efficiency may decline with erythrocyte aging (Lane et al 1982;Lane 1984Lane , 1986. Thus, cell replacement may, in and of itself, confer an advantage.…”

Transcriptomic Analysis of Young and Old Erythrocytes of Fish

“…High transcriptional and translational activity is required in young, immature erythrocyte because they gradually undergo changes in cell shape, membrane rigidity and other properties until maturation (e.g., Lecklin et al, 2000; Tavares-Dias, 2006). In contrast, in old, mature erythrocytes the need for gene transcription and protein synthesis is much lower and the necessary machinery, such as ribosomes is very low (Lane et al, 1982; Phillips et al, 2000). A total of 51,226 unigenes could be identified in the present study but we found only 930 (1.8%) DEGs.…”

“…Here we have collected blood from rainbow trout in spring (May) when the proportion of young erythrocytes in the circulation increases with rising ambient water temperature (Härdig and Hoglund, 1984; Alvarez et al, 1994; Houston et al, 1996; Lecklin et al, 2000). We have divided the erythrocytes in young and old cohorts on the basis of the old erythrocytes having higher density than young ones (Lane et al, 1982; Tiano et al, 2000). Since old erythrocytes have higher mean cellular hemoglobin concentration (MCHC) than young ones (Lane et al, 1982), the success of age separation was checked by evaluating MCHC.…”

“…We have divided the erythrocytes in young and old cohorts on the basis of the old erythrocytes having higher density than young ones (Lane et al, 1982; Tiano et al, 2000). Since old erythrocytes have higher mean cellular hemoglobin concentration (MCHC) than young ones (Lane et al, 1982), the success of age separation was checked by evaluating MCHC. Thereafter RNA sequencing was carried out and differences in transcriptomes in the young and old cohort evaluated.…”