Progressive changes in haematology and tissue water of sexually mature trout, Salmo gairdneri Richardson during the autumn and winter

Rainbow trout of the Kamploops variety were sampled at intervals from October to the end of March. During this period a decline was noted in red cell count, haematocrit, haemoglobin concentration and plasma osmotic concentration. Increases were seen, however, in mean cellular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration and the water content of liver and dorsal muscle. Sexual differences were found in all values with the exception of mean corpuscular haemoglobin concentration and the water content of both tissues. Males always had higher values in those parameters in which sexual differences were noted. All trends, with the exception of male haemoglobin and mean cellular volume and female mean cellular volume and osmotic concentration, were significantly linear.
None of the findings in this study could be correlated with temperature or photoperiod. Neither could the declining plasma osmotic concentration be correlated with the rising mean cellular volume or tissue water content. However, correlations were noted between haemoglobin and haematocrit, red cell count and haematocrit and between osmotic concentration and haematocrit. A negative correlation was seen between mean corpuscular haemoglobin concentration and mean cellular volume.     

Effect of litter size on blood haematocrit and liveweight in Booroola Merino and Merino ewes during pregnancy and the post-partum period

Blood haematocrit and liveweight were determined throughout pregnancy and the post-partum period in 217 Booroola Merino and Merino ewes in order to relate these parameters to litter size at birth. In pregnant ewes, haematocrit declined from three until five months gestation, rose immediately after parturition then declined until two months post-partum. During the third to fifth month of gestation, haematocrit decreased in proportion to litter size. Nonpregnant ewes, measured at similar intervals, did not show the same pattern. Haematocrit of nonpregnant animals was higher than that of triplet-bearing ewes at three, four and five months gestation, but was only significantly different to single- and twin-bearing ewes at five months. The liveweight of pregnant ewes increased up to parturition and then declined until two months post-partum. The liveweight of nonpregnant ewes increased over the experimental period. It was concluded that the number of foetuses a ewe carried had significant effects on the decline in haematocrit during pregnancy. Haematocrit was not a precise indicator of litter size in sheep. Haematocrit, ewe liveweight and ovulation rate together in a multiple regression only accounted for 37% of the variation in litter size.     

Seasonal variation in haematological parameters in male and female Tinca tinca

This study was designed to investigate any seasonal (spring, summer, autumn and winter) changes in haematological parameters in the blood of Tinca tinca measuring the number of red blood cells (RBC), haematocrit, white blood cells, and total plasma proteins.The results show significant changes in RBC and haematocrit in males comparing spring and summer with autumn and winter, whereas in females the RBC remained constant for all 4 seasons but the haematocrit decreased in autumn and winter compared to spring and summer. The white blood cells of male and female animals were significantly lower in spring and winter compared to summer and autumn. In male fish total protein contents significantly decreased in autumn and winter compared to spring and summer, whereas in females protein output significantly decreased in winter compared to the other seasons. The results indicate marked seasonal variation in the blood of male and female Tinca tinca. This variation may play a important protective role for the survival of the animals.     

Seasonal Ichthyodiversity and Growth Patterns of Juvenile Flatfish on a Nursery Ground in the Southern Bight of the North Sea (France)

The demersal fish community on a flatfish nursery ground, of the Southern Bight of the North Sea, was sampled monthly between May 1998 and 1999. The studied coastal area is a multispecific nursery area. Although 32 fish species were caught, only nine species had a major influence on the variation in total densities through the year and can be considered as key species. Juvenile sole and plaice exhibited similar seasonal growth patterns with rapid growth during late spring and summer, a growth arrest during autumn and winter and a restart of growth in March. Comparisons of observed growth in length with predicted maximal growth under optimal food conditions suggested that during the summer, growth of 0-group sole and plaice was only determined by prevailing mean water temperature. During autumn and winter, while growth in length of sole followed model predictions, observed length of plaice was less than model predictions, suggesting growth limitation. Analyses of the factors that may be responsible for differences between observed and expected length growth indicated that autumn and winter growth arrest of plaice was not only related to low winter water temperature. It is suggested that for visual feeders such as plaice, the interaction of decreasing food availability and day length during autumn and winter can reduce the access to food resource and therefore feeding success and growth.     

Alkaline hemolysis fragility is dependent on cell shape: results from a morphology tracker.

BACKGROUND: The morphometric analysis of red blood cells (RBCs) is an important area of study and has been performed previously for fixed samples. We present a novel method for the analysis of morphologic changes of live erythrocytes as a function of time. We use this method to extract information on alkaline hemolysis fragility. Many other toxins lyse cells by membrane poration, which has been studied by averaging over cell populations. However, no quantitative data are available for changes in the morphology of individual cells during membrane poration-driven hemolysis or for the relation between cell shape and fragility. METHODS: Hydroxide, a porating agent, was generated in a microfluidic enclosure containing RBCs in suspension. Automatic cell recognition, tracking, and morphometric measurements were done by using a custom image analysis program. Cell area and circular shape factor (CSF) were measured over time for individual cells. Implementations were developed in MATLAB and on Kestrel, a parallel computer that affords higher speed that approaches real-time processing. RESULTS: The average CSF went through a first period of fast increase, corresponding to the conversion of discocytes to spherocytes under internal osmotic pressure, followed by another period of slow increase until the fast lysis event. For individual cells, the initial CSF was shown to be inversely correlated to cell lifetime (linear regression factor R=0.44), with discocytes surviving longer than spherocytes. The inflated cell surface area to volume ratio was also inversely correlated to lifetime (R=0.43) but not correlated to the CSF. Lifetime correlated best to the ratio of cell inflation volume (Vfinal-Vinitial) to surface area (R=0.65). CONCLUSIONS: RBCs inflate at a rate proportional to their surface area, in agreement with a constant flux model, and lyse after attaining a spherical morphology. Spherical RBCs display increased alkaline hemolysis fragility (shorter lifetimes), providing an explanation for the increased osmotic fragility of RBCs from patients who have spherocytosis.     

Effect of vitamin C and zinc on osmotic fragility and lipid peroxidation in zinc-deficient haemodialysis patients

Peroxidation of the membrane lipid structure of red blood cell leads to haemolysis and anaemia in haemodialysis patients. Dietary constituents of antioxidant vitamins and trace elements may play an important role in protecting against oxidant damage. In this study, the effects of supplementation of vitamin C and zinc on osmotic fragility and lipid peroxidation of erythrocytes were investigated in 34 zinc-deficient haemodialysis patients. Sixteen sex- and age-matched normal volunteers acted as controls. Patients were randomized to receive vitamin C (250 mg day(-1)), zinc (20 mg day(-1)) or a placebo treatment for 3 months. The levels of vitamin C, zinc, malondialdehyde (MDA) and osmotic fragility were measured initially and 3 months after supplementation. Mean serum concentration of vitamin C and zinc increased significantly in the groups at the end of the respective study periods. Supplementation with vitamin C and zinc improved osmotic fragility, and decreased the level of MDA in the groups, but some side-effects (i.e. nausea, vomiting, fever, muscle pain, weakness) were observed during the zinc treatment. The results showed that the supplementation of both treatments decreased osmotic fragilty and MDA in zinc-deficient haemodialysis patients. However, vitamin C treatment was found to be safer than zinc supplementation.     

Effects of daily management stress on haematology and blood rheology of the gilthead seabream

Haematological and haemorheological responses against a moderate management stress, applied for 2 weeks, have been studied in the gilthead seabream ( Sparus aurata ). The stress application leads to a significant reduction in circulating erythrocytes, which caused decreased blood viscosity. Although erythrocyte osmotic fragility showed a trend inversely related to the duration of management stress, no significant change in cell dimensions, aggregation and deformation indices was observed. Consequently, the decrease in oxygen transport capacity attributable to haematocrit reduction, is not compensated by a qualitative change in the microrheological behaviour of erythrocytes, since the blood viscosity decreases as a direct result of the decline in red blood cell number.     

The dispersion of sole, Solea solea and plaice, Plemonectes platessa within and away from a nursery ground in the Irish Sea

Populations of sole and plaice were sampled on and around a nursery on the North Wales coast during May, July arid October 1989 and 1990, and the distribution of age-groups described. Pre-recruit sole were tagged and reieased on the same area during September 1988 to provide information on their larger scale movements. Juvenile sole remained on the nursery ground close inshore until after their first winter, whereas plaice of the same age—group became more widely dispersed. Both species were still associated with the coastal zone as 2-groups, when they were vulnerable to capture by commercial trawls. The gradual movement of sole out of the nursery was almost complete by October of their third year. Sole tag returns were obtained mainly from the NE Irish Sea. and also from the E coast of Ireland. Only three of the 68 returns came from outside the Irish Sea, one from the SE Irish coast, one from Swansea Bay and another from the outer Bristol Channel. Published data indicated that plaice undergo more rapid and more extensive migrations within and away from the Irish Sea than sole of the same age-group. Juvenile plaice and sole populations from nursery grounds throughout the NE Irish Sea would become mixed, and could contribute to any of the spawning populations in that area.     

Tidal stream mediation of metapopulation structure in North Sea plaice

Migration is widespread among marine fishes, yet little is known about variation in the migration of individuals within localities. We tested the hypothesis that variation in the migratory behaviour among plaice (Pleuronectes platessa) in the North Sea could be explained by large‐scale differences in the speed and directions of the tidal streams, which the fish use as a transport mechanism. Towards this end, 752 mature female plaice tagged with electronic data storage tags were released at eight locations with contrasting tidal flow properties, between December 1993 and September 1999. The experiment yielded 20 403 days of data from 145 plaice. The position of each fish was determined at intervals throughout the liberty period using the tidal location method. The results show 3 geographically discrete feeding aggregations during the summer, which dispersed over the southern North Sea and Eastern English Channel to spawn during winter. Our results re‐affirmed the major role of the tidal streams in the southern North Sea in structuring plaice dispersion, both by providing transport and guidance, and by delimiting the extent of distribution due to thermal stratification during the summer. These results confirm the prediction that large‐scale variation in migration behaviour can be explained in part by the tidal guidance and transport mechanisms available. They have revealed features of spatial dynamics not previously observed from a century of conventional tagging experiments and illustrate how the study of individual fish can successfully define the migratory characteristics of populations.     

Seasonal changes in the haematological indices in peripheral blood of chinchilla (Chinchilla laniger L.)

Changes in nine haematological indices in adult female and male chinchilla were investigated over a period of 18 months. All haematological values were in the same range both for females and males, although seasonal fluctuations were more evident in the females. High levels of the red blood cells count (RBC), haemoglobin concentration (Hb), mean cell haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) during the winter months and low levels of these parameters during the summer months were found. The white blood cells count (WBC) and lymphocyte number (L) also decreased in summer, their values increasing during autumn and spring. The haematocrit values (Ht) and mean cell volumes (MCV) are high during the summer and low during the winter.     

Sex‐biased dispersal in a salmonid fish: implications for growth rate and survival

Migration is widespread among marine fishes, yet little is known about variation in the migration of individuals within localities. We tested the hypothesis that variation in the migratory behaviour among plaice ( Pleuronectes platessa ) in the North Sea could be explained by large‐scale differences in the speed and directions of the tidal streams, which the fish use as a transport mechanism. Towards this end, 752 mature female plaice tagged with electronic data storage tags were released at eight locations with contrasting tidal flow properties, between December 1993 and September 1999. The experiment yielded 20 403 days of data from 145 plaice. The position of each fish was determined at intervals throughout the liberty period using the tidal location method. The results show 3 geographically discrete feeding aggregations during the summer, which dispersed over the southern North Sea and Eastern English Channel to spawn during winter. Our results re‐affirmed the major role of the tidal streams in the southern North Sea in structuring plaice dispersion, both by providing transport and guidance, and by delimiting the extent of distribution due to thermal stratification during the summer. These results confirm the prediction that large‐scale variation in migration behaviour can be explained in part by the tidal guidance and transport mechanisms available. They have revealed features of spatial dynamics not previously observed from a century of conventional tagging experiments and illustrate how the study of individual fish can successfully define the migratory characteristics of populations.     

Erythrocyte osmotic fragility and cation concentrations during experimentally induced bovine anaplasmosis

1. The osmotic fragility, the concentrations of Na, K and Ca, the osmolality and the total ATPase activity of bovine erythrocytes from uninfected and Anaplasma marginale-infected bovines were studied in an attempt to correlate these parameters with the decrease in the cellular ATP concentration reported during bovine anaplasmosis. 2. The osmotic fragility found in infected bovine erythrocytes, at 0.52% NaCl, was about two times greater than that observed in non-infected bovines. The increase in osmotic fragility was directly related to the increase in intra-erythrocytic parasitemia. 3. The decrease in ATP concentration reported during bovine anaplasmosis could not be directly related to the increased fragility of these cells. The artificial depletion of erythrocytic ATP did not reproduce the same alteration in the osmotic response to NaCl. 4. The plasmatic and cytoplasmatic concentrations of Na, K and CA did not change significantly during bovine anaplasmosis, whereas the interior of the erythrocytes became hyperosmolal. 5. A. marginale-infected bovine erythrocyte membranes showed an increased ATPase activity when compared to control bovines. Parasite-enriched fractions also presented ATPase activity.     

Acute toxicity of samorin (isometamidium chloride) in rabbits

Oral administration of samorin (isometamidium chloride) to rabbits in single oral doses of 6.25, 12.5, 25 and 50 mg/kg produced signs of toxicity which were dose-dependent. These were restlessness, hyperaesthesia, tremors, convulsions and finally death. Post mortem examination revealed fatty change, congestion and haemorrhage in many organs. Histopathological examination of liver, brain, kidneys and lungs showed severe circulatory changes and cellular damage. Measurement of serum constituents confirmed the presence of hepatic and renal damage. Samorin produced a marked fall in the erythrocyte count and the haematocrit values of all the treated rabbits, and in doses of 25 and 50 mg/kg it also increased the osmotic fragility of the erythrocytes.     

Characteristics and determinants of osmotic lysis in chromaffin granules

(1) Using isolated bovine chromaffin granules, we demonstrate that osmotic lysis is not a random process and establish the osmotic pressure dependence of osmotic lysis in chromaffin granules, the so-called osmotic fragility curve. (2) We show by measuring the release of constituents of the granule core and correlating these with changes in spectroscopic parameters (turbidity and endogenous catecholamine fluorescence), that the latter can be safely used to measure lysis. (3) Within a particular granule population, noradrenaline granules lyse at higher osmolarities than adrenaline granules, suggesting a higher core osmolarity of the noradrenaline granules. (4) The size distribution of chromaffin granules as a function of lysis was determined by the use of whole mount electron microscopy. It is shown that the mean size of chromaffin granules decreases as a function of lysis. (5) On the basis of theoretical considerations three alternative models of the sequence of osmotic lysis in chromaffin granules are proposed. The experimental results best support a model which postulates that during partial osmotic lysis, granule membranes reseal into smaller vesicles after graded release of contents. The osmotic fragility would represent several cycles of lysis and resealing and would not be a reflection of the distribution of osmotic pressures in the granule population.     

Relationship of season, thermal loading and red-sore disease with various haematological parameters in Micropterus salmoides

One hundred and fifty largemouth bass (Micropterus salmoides) were caught during the mid-winter and mid-summer months in Par Pond, an 1120 ha cooling reservoir located on Savannah River Plant near Aiken, SC. Equal numbers of fish were taken from ambient and thermally altered (> 10° C ambient) areas of the lake. The total length and weight of each bass was noted, along with the presence or absence of lesions associated with red-sore disease (caused by the bacterium, Aeromonas hydrophila and the ciliate, Epistylis sp.). Blood was drawn, by heart puncture, from each bass and the following haematological parameters measured: haematocrit, haemoglobin, iron, total iron-binding capacity, thyroxine, sodium and potassium. Only the total iron-binding capacity was significantly higher in bass with red-sore disease; none of the other blood parameters were significantly different in infected and uninfected bass. Bass from thermally altered locations had consistently higher haematocrits during both summer and winter. Bass from thermal and ambient locations were not different with respect to iron, iron-binding capacity, sodium or potassium levels. However, bass taken during summer months had higher levels of circulating iron than individuals in winter months. Summer bass had higher thyroxine levels than bass in winter. These results are discussed in terms of their relationship to red-sore disease, season and the impact of thermal effluent.     

低强度激光对人红细胞生物物理特性的影响

研究不同功率的低强度He-Ne激光对正常人体红细胞流变学特性影响。以正常人体红细胞为研究对象,测量了低强度He-Ne激光在不同照射时间、不同功率条件下红细胞的变形、取向、膜流动性、膜的微粘度和渗透脆性的变化情况。结果表明:照射后红细胞的变形性和膜流动性增强、渗透脆性下降。照射对红细胞流变学特性影响显著,其中激光能量为0.24 J、照射血样为2 mL时取得的照射效果最佳。     

Phase dependence in winter physiological condition of cyclic voles

Lack of food resources has been suggested as a factor which limits the growth of cyclic vole populations. During peak phases of the cycle, vole population growth typically ceases during late autumn or early winter, and is followed by a decrease in density over the winter. To investigate whether this decrease is due to increased mortality induced by a depletion of food resources, we studied overwinter food consumption and physiological condition of field voles ( Microtus agrestis ) in western Finland in both an increase and a decrease phase of a three-year population cycle. The growth rate of vole populations was negatively related both to prevailing vole densities and to densities six months earlier. The condition index of voles, as well as their blood levels of haematocrit, proteins, free fatty acids and immunoglobulin G, were positively related to population growth rate when populations were declining. When populations were increasing, these parameters tended to be negatively related to population growth rate. The overall physiological condition of voles was lower in the winter of the decrease phase as compared to the increase phase. The return rate of voles, a proxy of survival, was also lower in the decrease than in the increase phase of the cycle and positively related to haematocrit levels. Almost 90% of all green vegetation shoots were consumed by voles during the winter of the decrease phase while only two thirds were eaten in the increase phase. Our results suggest that the winter decrease phase of cyclic vole populations is associated with both a deterioration in the physiological condition of voles and a significant depletion of winter food resources. This implies that malnutrition induces poor physiological condition in voles, which in turn may increase mortality either directly through starvation or indirectly through increased susceptibility to predators and pathogens.     

Quantitative seasonal changes in the protein, lipid and energy content of the carcass, ovaries and liver of adult female plaice, Pleuronectes platessa L.

A detailed study was made of the seasonal changes in energy reserves in adult female plaice, Pleuronectes platessa L. The weights of lipid, protein, glycogen and ash in the carcass, liver and ovaries were measured in females approximately 35 cm long on ten occasions during one year. These data were converted to data for a'real'growing female by using a growth curve to take account of increasing length during the year. Growth of the whole body and of the body components was assumed to be isometric.
Plaice show a marked seasonal cycle of body weight and energy content. A six year old female plaice of 330 g, 32.6 cm long and with an energy content of 406 kcal in May, assimilates 560 kcal before December when it ceases to feed. Of this, 234 kcal is used to produce eggs, 159 kcal is used for metabolism during starvation, and the remainder 167 kcal, is used in growth. There is an increase in length to 35.9 cm and in weight to 462 g over the year. From December until March, when plaice do not feed but grow large ovaries, 40% of the protein in the body is utilised, 33% is devoted to egg production and 7% is metabolised to provide energy; 64% of the lipid is used, only 14% being used for egg production but 50% is metabolised for energy. Lipid supplies 75% of the energy for metabolism and so forms the major reserve; 42% of the energy assimilated during the year is devoted to reproduction. The main source of lipid and protein reserves is the carcass.     

The settlement, distribution and movements of O-group plaice Pleuronectes platessa (L.) in Filey Bay, Yorkshire

The pelagic larval stages and the demersal O-group stage of plaice were sampled in the immediate vicinity of Filey Bay, Yorkshire (54°12'N, 00°16'W), using a modified Gulf V high-speed plankton sampler and beam trawls. The distribution and movements of these fish were studied from the time of first settlement in May through the period of metamorphosis and the O-group stage. It was found that the larvae settled in water deeper than 5 m and moved into shallow water following metamorphosis. This established a typical distribution of larger fish in shallower water than the smaller fish. When the fish grew over 40 mm they moved out again into deeper water which leads to a reversal of the lengthdepth distribution. Further movements during the winter months and of the I-group fish were studied by tagging. It was found that emigration from the nursery ground did not occur until the I-group stage.     

The relationship between the osmotic fragility of human erythrocytes and cell age

Erythrocytes in a normal blood sample are hemolyzed over a range of hypotonic salt concentrations. In order to investigate the relationship between the distribution of osmotic fragilities and the distribution of cellular ages, the osmotic fragility has been compared with three indices of cellular age. The activity of glutamic-oxalacetic transaminase (GOT) and the percentage hemoglobin A_1C were measured in samples hemolyzed in different hypotonic salt concentrations. The osmotic fragility curve was also obtained for cells of different density separated by centrifugation. These experiments indicate that the fragility distribution is not an accurate reflection of the distribution of cellular ages. The mean fragility for older cells is higher than that of younger cells. However, cellular aging does not produce a gradual increase in osmotic fragility. Instead, it seems to produce changes which can both increase and decrease the fragility, resulting in a broader distribution of fragilities with some of the older cells actually less fragile than the younger ones.