bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of temperature on the deformability of a lamprey, Entosphenus japonicus, and Pacific salmon, Oncorhynchus keta, red blood cells, studied using a modified filtration method
Authors: Hughes G. M. , Koyama T. 
Published: January 2006

The rates of filtration through Nuclepore filters (5 or 8 μm) of blood from lampreys and Pacific salmon have been studied using a method which visualizes the flow pattern. From these measurements, passage times for single red blood cells have been calculated and serve as an index of their deformability. The deformability increases as temperature is raised in vitro, but even at 5°C the passage time of lamprey blood is relatively rapid. The increase in deformability with a rise in temperature is small relative to that found in other fish such as yellowtail and carp.The distribution of red cell volumes has shown the presence of a secondary peak for salmon blood taken during surgery which is reduced following recovery, the main peak being at a lower volume.
Fish impingement at estuarine power stations and its significance to commercial fishing
Authors: Turnpenny A. W. H. 
Published: January 2006

The abstraction of cooling water at power stations sited on tidal waters inevitably leads to mortalities of some fish which are drawn in with the cooling water supply and become impinged on the intake screens. These fish are predominantly 0‐ or I‐group juveniles which, owing to their small size, are unable to resist intake currents.Commercial fishermen often object to the fact that juvenile fish are killed in this way. Their concern stems from the fact that, in order to protect stocks, commercial fishing is restricted to fish which are above a statutory minimum landing size, whereas the majority of fish killed by impingement are below this size.This paper considers the significance of impingement mortalities at estuarine sites in Britain for six commercially important species: cod, Gadus morhua, whiting, Merlangius merlangus, plaice, Pleuronectes platessa, dab, Limanda limanda, sole, Solea solea and herring, Clupea harengus. Life tables are used to establish expected survival trajectories for each species and to compute reproductive potential. Each fish killed on intake screens is then considered in terms of the fraction of the reproductive potential of a single adult at maturity, and is ascribed an ‘adult equivalent’ value. Total catches of mixed juveniles and adults are then presented as ‘adult equivalent’ values. The results are then compared with commercial landings data and it is shown that catches by power stations are trivial in comparison with commercial landings.
Movements of juvenile Dover sole, Solea solea (L.), in the Tamar Estuary, South‐western England
Authors: Coggan R. A. , Dando P. R. 
Published: January 2006

Solea solea start to appear in the Tamar Estuary in April–May when they are 10 mm long. The majority of young sole move into the estuary in June–July. Most sole leave the estuary towards the end of their second year in October–November, when they have reached a total length of 150–200 mm. The young O‐group fish remain in the main channel, whereas the I‐group move with the tide onto the mud‐flats.Approximately 7000 fish were marked by freeze‐branding or dye‐injection. The recaptures showed that there was an up‐estuary migration in May–June. Most of the recaptures were taken at the site of original capture and there was only a limited movement of fish between adjacent mud‐flat areas. Average growth rate tends to be greater in sole inhabiting the upper reaches of the estuary.
The influence of three unchanging photoperiods on growth and parr‐smolt transformation in Atlantic salmon, Salmo salar L.
Authors: Stefansson S. O. , Naevdal G. , Hansen T. 
Published: January 2006

Groups of pre‐smolt Atlantic salmon were reared under three experimental photoperiods. Growth rate was significantly enhanced under 24 h of light: 0 h of darkness per diem (24 L: 0 D) compared with 16 L: 8 D and 8 L: 16 D from early January to early May. From the beginning of May until the termination of the experiment on 27 May, growth rate was highest under 8 L: 16 D.All groups developed bimodal length‐frequency distributions during the experiment. The proportion of the population in each of the two growth modes was significantly affected by photoperiod treatment.The level of plasma cortisol increased significantly from February to May. There were no differences in levels of plasma cortisol among photoperiod treatments.Judged by development in plasma cortisol, changes in condition factor and external appearance, the parr‐smolt transformation was not completed under any of the experimental photoperiods.
The effect of ultrasonic tags on the growth rates of Atlantic salmon, Salmo salar L., parr of varying size just prior to smolting
Authors: Greenstreet S. P. R. , Morgan R. I. G. 
Published: January 2006

The attachment of dummy, ultrasonic, acoustic tags, of the Stirling Mk. VI design, to pre‐smolt Atlantic salmon parr significantly affected fish growth rates. Fish less than 160 mm in length lost weight and showed no change in length. Fish over 160 mm in length put on weight, though at a rate significantly lower than that of untagged controls. For fish between 160 and 180mm in length, the increase in length was significantly smaller in tagged fish than in untagged controls. Over 180 mm in length, no difference could be detected in the length gains of tagged and untagged fish.Smaller tagged fish gave up maintaining station and showed signs of distress at an earlier stage in the experiment than larger tagged fish. Tag‐related mortality was inversely related to fish size. All but two of the control fish survived the experiment and continued to maintain station throughout.The results suggest that the minimum length of Atlantic salmon parr on which this design of acoustic tag could be employed is 160 mm, and that caution is needed in the interpretation of track lengths longer than l0 daysof parr in the size range 160–180 mm.
Oxygen consumption by eggs and larvae of striped mullet, Mugil cephalus, in relation to development, salinity and temperature
Authors: Walsh W. A. , Swanson C. , Lee C.‐S. , Banno J. E. , Eda H. 
Published: January 2006

Oxygen consumption rates during embryonic and the first 38 days of larval development of the striped mullet were measured at 24° C by differential respirometry. Measurements were obtained at the blastula, gastrula and four embryonic stages, and at the yolk‐sac, preflexion, flexion and post‐flexion larval stages.Oxygen uptake rates of eggs increased linearly from 0.024 μl O2 per egg h‐1 (0·323 μl O2 mg‐1 dry wt h‐1) by blastulae to 0·177 μlO2 per egg h‐1 (2·516 μlO2mg 1dry wth‐1) by embryos prior to hatching. Respiration rates did not vary significantly among four salinities (20,25, 30, 35%0).Larval oxygen consumption increased in a curvilinear manner from 0·243 μl O2 per larva h‐1 shortly after hatching to 18·880 μl O2 per larva h‐1 on day 38. Oxygen consumption varied in direct proportion to dry weight. Mass‐specific oxygen consumption rates of preflexion, flexion, and postflexion larvae did not change with age (10·838 μl O2 mg 1dry wt h‐1).Larval oxygen consumption rates did not vary significantly among salinities 10–35%. Acute temperature increases elicited significant increases in oxygen consumption, these being relatively greater in yolk‐sac larvae (Q10= 2·75) than in postflexion larvae (Q10= 1·40).
Histological structure of the intestine and pyloric caeca of the green sunfish, Lepomis cyanellus Rafinesque
Authors: Williams J. A. , Nickol B. B. 
Published: January 2006

A histological study was made of the intestine and pyloric caeca of green sunfish, Lepomis cyanellus (Centrarchidae). The intestinal and caecal walls are histologically very similar, consisting of a mucosa (epithelial layer), submucosa (lamina propria and stratum compactum), muscularis (circular and longitudinal layers) and the serosa. Cellular constituents of the mucosal layer include absorptive, columnar epithelial cells, mucous‐secreting goblet cells, and various leucocytes, the majority of which are lymphocytes. Other than relative size and the entrance of the bile duct at the base of the first caecum, no difference was found among caeca.When fish were nutritionally stressed, a greater variety and number of leucocytes and shifts in the numbers of lymphocytes and goblet cells of the mucosal layer were the only observable effects.
Sexual dimorphism in the energetics of reproduction and growth of North Sea plaice, Pleuronectes platessa L.
Authors: Rljnsdorp A. D. , Ibelings B. 
Published: January 2006

The chemical composition and energy content of North Sea plaice during the spawning period were examined in mature males and females and in immature fish, to study differences in the allocation of energy over reproduction and somatic growth between the sexes.At the beginning of the spawning period mature males and females had equal dry weights of lipid that were 70% higher than in immatures. Protein content in mature males was equal to that in immatures but was 23 % higher in mature females. Immature males and females did not differ in chemical composition. At the end of the spawning period, spent and immature fish had equal lipid contents, but protein content in spent females was 10% lower than in spent males, and 17% lower than in immatures. Gross energy content of the body decreased by 44% (65·2 to 36·3 J cm‐3) in mature females, 27% (55·0 to 40·OJ cm‐3) in mature males, and 9% (48·7 to 44·2J cm‐3) in immatures. Energy content of plaice eggs was estimated at 6·60 kJ per 1000 eggs.Reproductive investment was estimated from the energy loss during the spawning period and included the energy of sex products and spawning metabolism. Somatic growth comprised the annual increase in energy content of fish. The pattern of energy allocation over reproduction and somatic growth differed between males and females. Males started their reproduction at a smaller length and a younger age and allocated a higher proportion of the available energy into reproduction than females. Available energy resources for somatic growth and reproduction (surplus production) were equal between the sexes up to a length of about 30 cm. Beyond this length male surplus production levelled off whereas female surplus production continued to increase. The differences in surplus production and the allocation patterns are discussed.For female plaice the energy allocated into egg production was estimated as between 48 and 64% of the total amount of energy lost during spawning. The remaining energy is used for metabolism during the spawning period, yielding an estimate of the metabolic rate of mature females of between 6·4 and 9·1 kJ day‐1. A maximum estimate of the metabolic rate of mature males was 7·4 kJ day‐1.
Cadmium exposure of rainbow trout, Salmo gairdneri Richardson: effects on immune functions
Authors: Thuvander A. 
Published: January 2006

Differential leucocyte counts, phagocytosis, humoral antibody response and the in vitro blasto‐genetic response to mitogens (lipopolysaccharide and Concanavalin A) and to an antigen (Vibrio anguillarum) were studied in rainbow trout exposed to 0,0.7 or 3.6 μg Cd 1−1 for 12 weeks.Although the fish did not exhibit any clinical or histological changes, cadmium exposure was found to affect two of the immune parameters measured. The cellular response of fish immunized with V. anguillarum to the homologous antigen was significantly lower for splenocytes obtained from fish exposed to cadmium for 9 weeks (3.6 μg Cd 1−1 group) than for splenocytes obtained from non‐exposed fish. Conversely, the humoral antibody response to V. anguillarum O‐antigen was higher in the 3.6 μg Cd 1−1 group than in the non‐exposed group. Protective immunity of fish vaccinated against V. anguillarum was equally as good in the cadmium‐exposed group as in the non‐exposed group. No cadmium‐induced changes in differential leucocyte counts or in the proportions of phagocytic cells were observed.
Immunological importance of the second gut segment of carp. I. Uptake and processing of antigens by epithelial cells and macrophages
Authors: Rombout J. H. W. M. , van den Berg A. A. 
Published: January 2006

Uptake and transport of soluble (ferritin) and particulate (Vibrio anguillarum) antigen from intestinal lumen to mucosal macrophages was studied using immunocytochemical and electron‐microscopical techniques. Both antigens were taken up by epithelial cells of the second gut segment, reached the supranuclear vacuoles and were finally transported to large intraepithelial macrophages. In contrast with particulate antigen, antigenic determinants of ferritin were demonstrated in the basal part of the epithelium and appeared to be released at the mucosal site.After anal intubation many small macrophages penetrated the intestinal epithelium, took up antigen and after 24 h disappeared again from the intestinal mucosa. This feature was antigen independent and also occurred after anal PBS‐intubation. The larger, less mobile macrophages stayed in the intestinal epithelium and finally exposed antigenic determinants (of both antigens) at their outer surface, suggesting an antigen‐presenting function. Whether these large macrophages can induce a local or mucosal immune response and whether the smaller mobile macrophages are involved in a systemic response is discussed.
Intraspecific genetic differentiation of Leporinus friderici (Anostomidae, Pisces) in French Guiana and Brazil: a genetic approach to the refuge theory
Authors: Renno J.‐F. , Berreb P. , Boujard T. , Guyomard R. 
Published: January 2006

A genetic study was carried out on a neotropical fish species to illustrate the refuge theory, whose main principles are summarized. The geographical structure of the anostomid species Leporinus friderici was analysed in French Guiana and Brazil by horizontal starch gel electrophoresis. Fifteen enzymatic systems corresponding to 21 loci were studied, revealing the following particularities: (1) specimens of fish from six independent coastal rivers of French Guiana form two groups geographically situated on either side of the Kourou River; (2) two alleles can serve as geographic markers, Ldh2(l30) showing an affinity between the populations in eastern French Guiana and Brazil, and Me 1(300) being specific to the west.These observations are probably related to the refuges that were formed in the Quaternary in South America, especially on the Guiana Shield. We consider that the populations of French Guiana are separated into two groups at the boundary between the two migratory flows, one arising in the west from the refuge of the Guiana Shield and the other in the east from a nearby undetermined Amazonian refuge.
Spatial and temporal dispersion patterns of golden perch, Macquaria ambigua, larvae in an artificial floodplain environment
Authors: Gehrke Peter C. 
Published: January 2006

Golden perch larvae were stocked into a pond and inundated floodplain system in south‐eastem Australia to determine movement patterns of the larvae onto and off the floodplain area. A total of 428 larvae were caught moving from the floodplain into the pond whereas only 18 were collected moving in the reverse direction. Thirty one larvae were caught at open water sites in the pond and floodplain, but only three were collected from sites on the floodplain which provided shade, timber or water flow. Transect samples from the pond also yielded more larvae than samples from floodplain transects, indicating a distinct spatial dispersion pattern in favour of the pond.Spatial dispersion patterns of golden perch larvae appear to correspond with gradients in water quality between the pond and floodplain habitats. Stratification occurred in the pond but did not develop on the floodplain. Water on the floodplain was cooler, harder and contained less oxygen than surface water from the pond. Die1 oscillations occurred in water temperature, pH, dissolved oxygen, carbon dioxide and acidity, but there was no significant corresponding pattern in the distribution of larvae.Dispersion of golden perch larvae between pond and floodplain habitats is not random, and may be actively influenced by local‐scale variations in water quality.
Daily ration estimates for yellowfin sole, Limanda aspera (Pallas), based on laboratory consumption and growth
Authors: Smith R. L. , Paul A. J. , Paul J. M. 
Published: January 2006

Several estimates of minimal energy requirements for yellowfin sole were made. Energy expenditures of 1.6, 4.1 and 8.3 cal g−1 day−1 were obtained from starvation weight loss, standard metabolism and maintenance ration procedures, respectively, at 6° C. The temperature effect on energy requirement was reflected in the Q10 values for starvation weight loss (2.0), standard metabolism (6.3) and maintenance ration (6.5).Both energy intake and weight of food were linearly related to, and good predictors of, laboratory growth. These relationships were used to estimate the food and energy intake necessary for yellowfin sole to achieve a year's growth in the natural environment. Based on a caloric value of 2.0 kcal g−1 of food (herring fillets), yellowfin would require 0.35 to 0.39% body weight day−1 at 3° C to achieve the mean growth rate exhibited in the Bering Sea. To achieve Gulf of Alaska growth rates at 5 to 6° C, yellowfin would require 0.63% body weight day−1. Based on a caloric value of 0.57 kcal g−1 of food (chopped octopus), yellowfin would require 0.83% body weight per day to achieve the Gulf of Alaska growth rate (6° C). These requirements based on the calorific value of herring fillets, which are three to five times higher than previous estimates of daily ration in this species, are probably conservative estimates since many of their prey species have a lower energy content.
The effects of starvation and refeeding on plasma amino acid levels in carp, Cyprinus carpio L., 1758
Authors: Blasco J. , Fernández J. , Gutiérrez J. 
Published: January 2006

Plasma amino acid (AA) levels of carp, Cyprinus carpio L., 1758, were analysed after various periods of starvation as well as after 12 days of refeeding. The levels were compared to control groups, which had been previously fasted for 24 h. A positive correlation between dietary and plasma essential amino acid (EAA) concentrations was observed in all of the control groups.The effect of starvation on the dynamics of AA concentration was different according to the period of starvation. Fasting already produced a decrease of total α‐AA levels at 2 days, and these low levels were maintained until 5 and 8 days. These short periods of fasting affected the levels of EAA (especially branched‐chain AA) more than those of non‐essential amino acids (NEAA). The only AA that increased was Ala, which rose at 5 days of starvation, surpassing the levels of the control group. These high levels were maintained until 19 days of starvation.A different situation was observed at 19 days, when an important increase of total α‐AA levels was produced, the branched‐chain AA being the most notable among EAA and Glu/Gln among NEAA. Later, at 50 days of starvation, total α‐AA, EAA (except Leu and Ile) and NEAA decreased.After 50 days of starvation, 12 days of refeeding did not modify the levels of EAA and NEAA, and their concentrations were lower than those of the control group, which presented an increase of total AA at this time. The differences observed on the changes of individual AA levels are discussed.
Study of the soluble white muscle tissue proteins from fifteen Sparidae species
Authors: Basaglia F. , Marchetti M. G. 
Published: January 2006

Soluble proteins of white skeletal muscle tissue of 15 species of Sparidae were analysed. Species‐specific electrophoretic and isoelectric focusing patterns were found. Some bands exhibited the same mobility at genus level or at subfamily level, others differed significantly.Considerable similarity was observed in the species of the genera Spams, Pagellus and Diplodus. Significant differences in the protein bands were noted between the contained subfamilies Denticinae, Sparinae and Boopsinae, confirming the existence of three separate phyletic lines within the family Sparidae.This study has shown that in these species there is a similarity between classifications based on morphological data and those derived from biochemical studies.Variation within species can be corrected for by carrying out multiple inter‐specific comparisons and determining the variance of the similarity coefficients. Closely related species have similar patterns and, thus, higher similarity coefficients.The discrepancy in similarity matrices based on morphology and white skeletal muscle tissue proteins of sea bream species shows that electrophoretic methods provide additional information relevant to the systematics of fishes.Further work on comparison on soluble red muscle proteins of these species is proposed.
Stream channel experiments on downstream movement of recently emerged trout, Salmo trutta L. and salmon, S. salar L.—I. Effect of four different water velocity treatments upon dispersal rate
Authors: Crisp D. T. , Hurley M. A. 
Published: January 2006

Four experimental stream channels were used to study instantaneous downstream dispersal rates of young trout, Salmo trutta L., and salmon, S. salur L., relative to four different water velocities.Young salmon showed a high rate of dispersal at a low velocity of 7.5 cm s−1 and lower rates at higher velocities of 25 to 70cm s−1. Trout showed their lowest rate at 25cm s−1 with a slightly higher rate at 7.5 cm s−1 and increasingly higher rates at velocities in excess of 25 cm s−1. These results are consistent with field observations on the velocity preferences of young trout and salmon.
Stream channel experiments on downstream movement of recently emerged trout, Salmo trutta L., and salmon, S. salar L.—11. Effects of constant and changing velocities and of day and night upon dispersal rate
Authors: Crisp D. T. , Hurley M. A. 
Published: January 2006

Four experimental stream channels were used to study instantaneous downstream dispersal rates of young trout and salmon relative to day and night, constant low and high water velocities and changes of velocity from high to low and vice versa.At high and low velocity for trout and at high velocity for salmon, the dispersal rate was higher by night than by day. Changes of velocity during daytime from high to low or low to high for trout and from high to low for salmon, were associated with much higher dispersal rates than were constant velocities.
Stream channel experiments on downstream movement of recently emerged trout, Salmo trutta L., and salmon, S. salar L.—111. Effects of developmental stage and day and night upon dispersal
Authors: Crisp D. T. 
Published: January 2006

Four experimental stream channels were used to examine the temporal pattern of downstream dispersal of young salmon and trout at four constant water velocities from the time of emergence from the gravel onwards.At low water velocities (c. 8.0 cm s −1) young salmon showed a high rate of dispersal which was maintained until a very low population density was attained. At higher velocities salmon showed a lower rate of dispersal and the final population density was higher. Trout showed a low dispersal rate at low velocity and higher rates at higher velocities. However, the final trout population density was similar at all water velocities because the low dispersal rate observed at the low velocity persisted for a much longer period than did the higher values at the higher water velocities. The results do not support the view that young salmonids have a narrow and definable period of sensitivity to water velocity.Dispersal rates were significantly higher by night than by day (P <0.001) at all velocities for both fish species.