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Cm Total Length (cm + total_length)
Selected AbstractsCapillary electrophoretic chiral separation of hydroxychloroquine and its metabolites in the microsomal fraction of liver homogenatesELECTROPHORESIS, Issue 5-6 2006Carmem Dickow Cardoso Abstract A rapid, selective, and low-cost chiral capillary electrophoretic method was developed for the simultaneous analysis of hydroxychloroquine (HCQ) and its three chiral metabolites: desethylchloroquine (DCQ), desethylhydroxychloroquine (DHCQ), and bisdesethylchloroquine (BDCQ) in the microsomal fraction of liver homogenates. After liquid,liquid extraction using toluene as extracting solvent, the drug and metabolites were resolved on a fused-silica capillary (50,,m ID, 50,cm total length, and 42,cm effective length), using 100,mmol/L of Tris/phosphate buffer, pH,9.0 containing 1% w/v sulfated-,-CD and 30,mg/mL hydroxypropyl-,-CD. Detection was carried out at 220,nm. The extraction procedure was efficient in removing endogenous interferents, and low values (,15%) for CVs and deviation from theoretical values were demonstrated for both within-day and between-day assays. The quantitation limit was 125,ng/mL with linear response over the 125,2000,ng/mL of concentration range for all metabolites. After validation, the method was used for an in vitro metabolism study of HCQ. The major HCQ metabolite formed by microsomal enzymes was (,)-(R)-DHCQ. [source] Simultaneous detection of S -adenosylmethionine and S -adenosylhomocysteine in mouse and rat tissues by capillary electrophoresisELECTROPHORESIS, Issue 7-8 2003Eric O. Uthus Abstract A capillary electrophoresis method for the determination of S -adenosylmethionine (SAM) and S -adenosylhomocysteine (SAH) in rat liver and kidney and mouse liver is described. The method can also be used to determine SAM in whole blood. The method provides rapid (approximately 16 min sample to sample) resolution of both compounds in perchloric extracts of tissues. Separation was performed by using an uncoated 50 ,m ID capillary with 60 cm total length (50 cm to the detector window). Samples were separated at 22.5 kV and the separation running buffer was 200 mM glycine pH 1.8 (with HCl). The method compares favorably to HPLC methods (r,2 = 0.994 for SAM, r,2 = 0.998 for SAH) and has a mass detection limit of about 10 fmol for both SAM and SAH at a signal-to-noise ratio of 3. The method is linear over ranges of 1,100 ,M SAM and 1,250 ,M SAH. This method can be used to determine tissue concentrations of SAM and SAH, two metabolites that can provide insight into many biological processes. [source] Distribution and biomass of an underfished vendace, Coregonus albula, population in a mesotrophic German reservoirFISHERIES MANAGEMENT & ECOLOGY, Issue 3 2005M. B. SCHMIDT Abstract, The distribution and overall biomass of an underfished vendace, Coregonus albula L., population in the mesotrophic Henne Reservoir (Germany) was studied using hydroacoustics and gill nets. Additionally, midwater trawling was carried out. Overall fish biomass, based on five hydroacoustic surveys (June to September 2002), ranged from 188 kg ha,1 in early August to 302 kg ha,1 in September 2002. The overall mean fish biomass was 256 kg ha,1 (±48 kg ha,1 SD). Biomass of fish smaller than 25 cm total length (mostly vendace) varied from 56 kg ha,1 in August to 99 kg ha,1 in September, with an overall mean fish biomass of 74 kg ha,1 (±17 kg ha,1 SD). The echograms showed temporal variation in fish distribution in Henne Reservoir. In June, fish were fairly evenly distributed over the whole reservoir but in September a dense aggregation of fish (mostly vendace) was found in the deeper water layers near the dam. The distribution of vendace stock, its impact on water quality and fisheries management, biomanipulation and effort for mass removal are discussed. [source] Discards from the commercial gillnet fishery for dusky flathead, Platycephalus fuscus, in New South Wales, Australia: spatial variability and initial effects of change in minimum legal length of target speciesFISHERIES MANAGEMENT & ECOLOGY, Issue 5 2004C. A. Gray Abstract A scientific observer programme was used to quantify the composition and magnitude of discards in the gillnet fishery for dusky flathead, Platycephalus fuscus (Cuvier), in three barrier estuaries in New South Wales, Australia, during the 2001 fishing season. Regulations only permit the retention of legal-sized dusky flathead and legal-sized blue swimmer crab, Portunus pelagicus L., and mud crab, Scylla serrata (Forskål); all other organisms were discarded. Sampling was stratified into two time periods; before and after 1 July 2001 which coincided with the increase in the minimum legal length (MLL) of dusky flathead from 33 to 36 cm total length (TL). Eighty one catches were sampled, yielding 38 finfish species and two portunid crab species. Legal-sized dusky flathead were the most abundant organism captured, accounting for 23,47% by number and 34,54% by weight of the mean observed catch depending on the estuary and survey period, with a mean catch of 25,59 flathead weighing 13,25 kg per fishing-night. Species composition and relative abundance of catches differed among estuaries, but not between sampling periods. Predominant bycatch species included legal and undersize blue swimmer crab, sea mullet, Mugil cephalus L., luderick, Girella tricuspidata (Quoy & Gaimard), bream, Acanthopagrus australis (Günther) and yellowfin leatherjacket, Meuschenia trachylepis (Günther). These five species accounted for 82% of total bycatch by number and 71% by weight, pooled across the three estuaries. More crabs were retained than discarded, with retained legal-size crabs (byproduct) accounting for 16% of total bycatch by number and 13% by weight, with an average of 5,22 crabs weighing 1,6 kg being caught per fishing-night, depending on the estuary. Overall, 7% of dusky flathead captured (number) were below the MLL of 36 cm and discarded, suggesting the nets as currently configured may be relatively selective in catching legal-size flathead. However, 41% of dusky flathead were <40 cm TL, indicating that if the MLL for this species is increased to this length as proposed, new nets must be introduced into the fishery. The findings are discussed in terms of making the flathead fishery more sustainable, including alternative management strategies for the fishery. [source] Population Density of the Crayfish, Orconectes limosus, in Relation to Fish and Macroinvertebrate Densities in a Small Mesotrophic Lake , Implications for the Lake's Food WebINTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 5-6 2005Susanne S. Haertel-Borer Abstract The population density of Orconectes limosus in a mesotrophic lake was assessed in the context of fish and macroinvertebrate biomasses, and crayfish consumption by fish. The average O.limosus (,6 cm total length) abundance and biomass in the littoral zone was 2200 ind ha,1 and 32.2 kg ha1, respectively. O.limosus biomass accounted for a large percentage (49%) of the lake's macroinvertebrate biomass. O.limosus was equal to 35% of the non-predatory fish biomass and to 81% of the predatory fish biomass. O.limosus comprised 15 and 48% of the annual consumption of pike and predatory perch, respectively. Altogether, O.limosus was identified as quantitatively important for the lake's littoral food web, and might also subsidize the pelagic food web. This strengthens the need for an integrated view on lake food webs. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Age, growth and sexual development of solenette, Buglossidium luteum (Risso, 1810), in the central Aegean SeaJOURNAL OF APPLIED ICHTHYOLOGY, Issue 3 2010A. T., lkyaz Summary Age, growth, spawning period and maturity of the solenette (Buglossidium luteum Risso, 1810) were studied in the central Aegean Sea to provide fisheries managers with essential data for science-based management. A total of 1220 samples were collected by trawl hauls from July 2004 to June 2007 in ,zmir Bay (Turkey). Sample sizes ranging from 5.3 to 11.6 cm total length were composed of 46% females, 32% males and 22% immature individuals, with a female to male ratio of 1 : 0.7. Age composition stages of the females were from I to IV, and males between I and III. The length,weight relationship was calculated as W = 0.0101L3.008 for all samples. Estimated von Bertalanffy growth parameters were L = 13.30 cm, to = ,0.440 year and k = 0.481 year,1, with a growth performance index of 1.93 (,'). The spawning period began in April and continued until July. Lengths at first maturity of females and males were 8.1 and 7.9 cm total length, respectively. Both sexes matured at the age of 2 years. [source] Trophic variations of the Chilean croaker Cilus gilberti during the summer period 1997,98 (Perciformes, Sciaenidae)JOURNAL OF APPLIED ICHTHYOLOGY, Issue 5 2001C. Fernández The natural diet of the Chilean croaker, Cilus gilberti Abbott 1899, was studied in Queule and Tumbes, two areas in central-southern Chile, with emphasis on the possible influences of geographic distribution, sex and ontogenetic development on the croaker feeding habits. Results indicate that C. gilberti behaves in both locations as an euriphagic carnivore predator. The Queule population predate mainly on the sardine Strangomera bentincki Norman 1936, while at Tumbes the principal prey items were mysids. Further quantitative analyses showed that within the Queule population, females between 54 and 75 cm total length (TL), as well as those individuals exceeding 75 cm, acted as an Ontogenetic Trophic Unit (OTU). A Transitional OTU, which includes individuals between 47 and 54 cm, was also identified. Queule males between 47 and 68 cm defined one OTU; another OTU was defined with individuals between 68 and 82 cm. On the other hand, the female population at Tumbes behaved as an OTU between 68 and 89 cm TL; males were grouped in an OTU ranging from 61 to 89 cm TL. [source] Occurrence of pelagic stingray Pteroplatytrygon violacea (Bonaparte, 1832) in the North SeaJOURNAL OF FISH BIOLOGY, Issue 3 2007J. R Ellis A mature male pelagic stingray Pteroplatytrygon violacea (99 cm total length, 33·5 cm disc length and 42 cm disc width; 2·5 kg) was caught by commercial Nephrops trawl in the North Sea (at c. 54º49, N; 0º57, W) on 14 November 2005. Records of P. violacea in the north-east Atlantic are reviewed, with only two vagrant specimens known from the North Sea, representing the most northerly records of this species in the Atlantic Ocean. [source] Identifying individual great barracuda Sphyraena barracuda using natural body marksJOURNAL OF FISH BIOLOGY, Issue 3 2006S. K. Wilson Natural body marks on Sphyraena barracuda were recorded with digital images to identify individual fish. Over 18 months, 60 fish were photographed in situ, eight of which were re-photographed at later dates. Re-photographed fish were all large adults (>70 cm total length) and were all seen within 200 m of the site where they were originally observed 10,318 days prior. Over the same period and area, 116 fish were tagged using T-bar tags, yet none of these fish were recaptured. Natural body marks are thus an effective means of identifying and monitoring behaviour of individuals. [source] Embryos of common thresher shark Alopias vulpinus in southern Brazil, South Atlantic OceanJOURNAL OF FISH BIOLOGY, Issue 1 2006P. L. Mancini Eight embryonic thresher sharks Alopias vulpinus (53·9,124 cm total length) were collected from two females caught by commercial longline off southern Brazil in September and November 2004. Morphometric measurements are provided. [source] Prey consumption rates and growth of piscivorous brown trout in a subarctic watercourseJOURNAL OF FISH BIOLOGY, Issue 3 2006H. Jensen Prey consumption rates of piscivorous brown trout Salmo trutta were studied in the Pasvik watercourse, which forms the border between Norway and Russia. Estimates of food consumption in the field were similar to or slightly less than maximum values from a bioenergetic model. The piscivore diet consisted mainly of vendace Coregonus albula with a smaller number of whitefish Coregonus lavaretus. Individual brown trout had an estimated mean daily intake of c. 1·5 vendace and 0·4 whitefish, and a rapid annual growth increment of 7,8 cm year,1. The total population of brown trout >25 cm total length was estimated as 8445 individuals (0·6 individuals ha,1), giving a mean ± s.e. annual consumption of 1553880 ± 405360 vendace and 439140 ± 287130 whitefish for the whole watercourse. The rapid growth in summer of brown trout >25 cm indicated a high prey consumption rate. [source] Ovary development in Greenland halibut Reinhardtius hippoglossoides in west Greenland watersJOURNAL OF FISH BIOLOGY, Issue 5 2005C. S. Simonsen Maturity in adult female Greenland halibut Reinhardtius hippoglossoides was studied in three areas in west Greenland waters: the inshore area in Disko Bay and two offshore areas, Baffin Bay and Davis Strait. The aim was to monitor maturity changes in the inshore fjords of Disko Bay over an extended period from winter to autumn and compare these findings with specimens from Baffin Bay and the presumed spawning area in Davis Strait. A significant difference in maturity level was observed in and between the three areas. In Disko Bay maturity indices increased significantly in August and September both with respect to the gonado-somatic index (IG) and the size in the leading oocyte cohort. In the period February to May no significant changes were observed. Mature ovaries were only observed among fish >80 cm total length and only among a fraction of these large fish. Offshore areas of Baffin Bay, even though poorly sampled, showed similar signs in the maturity indices as in Disko Bay. Relative to Disko Bay and Baffin Bay, female fish in Davis Strait had more progressed maturity indices. Furthermore, almost all fish in Davis Strait showed signs of progressed maturity contrary to Disko and Baffin Bay. A large proportion of the Greenland halibut in Disko and Baffin Bay apparently did not begin the maturation cycle until very late in their life history or were repeat spawners with a multi-year maturation cycle. These observations could thus support the hypothesis that Greenland halibut have a prolonged adolescent phase. Atresia was highest in the early phases of maturation in Greenland halibut but relatively high levels of atresia were also observed in fish in more advanced maturity phase. The first was ascribed to fecundity regulation while the latter could be linked to the fish's fitness condition but it was not possible to show this with the available condition index. [source] Endurance swimming of European eelJOURNAL OF FISH BIOLOGY, Issue 2 2004G. Van Den Thillart A long-term swim trial was performed with five female silver eels Anguilla anguilla of 0·8,1·0 kg (c. 80 cm total length, LT) swimming at 0·5 body lengths (BL) s,1, corresponding to the mean swimming speed during spawning migration. The design of the Blazka-type swim tunnel was significantly improved, and for the first time the flow pattern of a swim tunnel for fish was evaluated with the Laser-Doppler method. The velocity profile over three different cross-sections was determined. It was observed that 80% of the water velocity drop-off occurred over a boundary layer of 20 mm. Therefore, swim velocity errors were negligible as the eels always swam outside this layer. The fish were able to swim continuously day and night during a period of 3 months in the swim tunnel through which fresh water at 19° C was passed. The oxygen consumption rates remained stable at 36·9 ± 2·9 mg O2 kg,1 h,1 over the 3 months swimming period for all tested eels. The mean cost of transportation was 28·2 mg O2 kg,1 km,1. From the total energy consumption the calculated decline in fat content was 30%. When extrapolating to 6000 km this would have been 60%, leaving only 40% of the total energy reserves for reproduction after arriving at the spawning site. Therefore low cost of transport combined with high fat content are crucial for the capacity of the eel to cross the Atlantic Ocean and reproduce. [source] Variation in the diet of the Patagonian toothfish with size, depth and season around the Falkland IslandsJOURNAL OF FISH BIOLOGY, Issue 2 2003A. Arkhipkin The ontogenetic and seasonal variations in the feeding spectrum were studied in 756 specimens of the Patagonian toothfish Dissostichus eleginoides (16,159 cm total length, LT) collected on the shelf, continental slope and bathyal waters (67,1960 m, depth range) around the Falkland Islands between April 1999 and August 2002. On the shelf, small toothfish (<40 cm LT) were active predators taking mostly one relatively large prey item at a time (mainly near-bottom Patagonotothen ramsayi and Loligo gahi). Medium-size toothfish (40,60 cm LT) fed on the same prey, but the number of prey items increased to 1,2 items per fish. Large toothfish (>60 cm LT) switched their diet to other large pelagic fishes occurring near the bottom (Macruronus magellanicus and Micromesistius australis australis), again taking mostly one prey item at a time. The diet of medium-size D. eleginoides on the shelf varied seasonally depending on the abundance and migrations of the major prey species. Patagonotothen ramsayi was abundant in the diet throughout the year, whereas L. gahi appeared only from February to October during its offshore seasonal migrations to the depth range of D. eleginoides. During November to January, L. gahi migrated inshore to spawn and disappeared from the toothfish diet, being substituted by M. australis australis which dispersed on the shelf after spawning. After its ontogenetic descent to the lower part of the continental slope (500,1000 m depths), toothfish took less active (than on the shelf) fishes such as Antimora rostrata whilst also feeding on active near-bottom macrourids and skates. In their deepest habitat (>1000 m depths), toothfish became a typical opportunistic predator, feeding mainly on relatively small and inactive fishes, squids and prawn-like crustaceans Acanthephyra pelagica and Thymops birsteini. Decrease in hunting activity with depth could be related to a specific adaptation to keep neutral buoyancy by increase of lipid content in white muscles of D. eleginoides with size. [source] Life stages and reproductive components of the Marmorkrebs (marbled crayfish), the first parthenogenetic decapod crustaceanJOURNAL OF MORPHOLOGY, Issue 3 2004Günter Vogt Abstract Recently, we briefly reported on the first case of parthenogenesis in the decapod Crustacea which was found in the Marmorkrebs or marbled crayfish, a cambarid species of unknown geographic origin and species identity. Curiously, this animal is known only from aquarium populations, where it explosively propagates. By means of light and electron microscopic techniques we have now investigated the reproductive components of this crayfish, using more than 100 specimens ranging from hatchling to repeatedly spawned adult. Additionally, we documented its principal life stages. Our results revealed that the external sexual characters and also the gonads of the marbled crayfish are purely female, making this fast-reproducing species a good model for investigating female reproductive features in crayfish. Testicular tissues, ovotestes, or male gonoducts, gonopores, or gonopods were never found, either in small juveniles or large adult specimens, confirming the parthenogenetic nature of this crayfish. Parthenogenesis may have arisen spontaneously or by interspecific hybridization since Wolbachia -like feminizing microorganisms were not found in the ovaries. The external sexual characters of the marbled crayfish are first recognized in Stage 4 juveniles and are structurally complete ,2 months after hatching in specimens of ,2 cm total length. In the same life stage the ovary is fully differentiated as well, although the oocytes are in previtellogenic and primary vitellogenic stages only. The architecture of the mature ovary and also the synchronous maturation of cohorts of primary vitellogenic oocytes by secondary vitellogenesis are in general agreement with data published on ovaries of bisexual crayfish. New results were obtained with respect to the muscular nature of the ovarian envelope and its extensive proliferation after the first spawning, the distribution of hemal sinuses in the ovarian envelope and in the interstitium around the oogenetic pouches, the high transport activity of the follicle cells, and the colonization of oogenetic pouches by previtellogenic oocytes that originate in the germaria. Investigation of the nuclei of oocytes in the germaria and oogenetic pouches revealed no signs of meiosis, as usually found in females of bisexual decapods, suggesting that parthenogenesis in the marbled crayfish might be an apomictic thelytoky. The detection of new rickettsial and coccidian infections in the ovary and further organs raises fears that the marbled crayfish might endanger native European species by transmission of pathogens once escaped into the wild. J. Morphol. 261:286,311, 2004. © 2004 Wiley-Liss, Inc. [source] Fast CE analysis of adrenergic amines in different parts of Citrus aurantium fruit and dietary supplementsJOURNAL OF SEPARATION SCIENCE, JSS, Issue 16 2010Laura Mercolini Abstract A CE method has been developed for the simultaneous analysis of the adrenergic amines synephrine, octopamine and tyramine in Citrus aurantium (bitter orange) fruit extracts and in dietary supplements. The analytes were separated on a fused silica capillary (50,,m id, 40.0,cm effective length, 48.5,cm total length) using a BGE composed of phosphate buffer (pH 2.5, 50,mM) and applying a 30,kV potential. The samples were injected hydrodynamically at 50,mbar for 25,s. The use of photodiode array detection (,=195,nm) allowed the quantification of the analytes and the control of peak purity. The method has been fully validated, obtaining satisfactory values of precision and extraction yield. The analytes are extracted with water from the dried whole fruits or fruit parts (endocarp, mesocarp and exocarp) or from the commercial formulations and directly injected into the CE apparatus. The results obtained were satisfactory in terms of precision (RSD <,5.7%) and accuracy (recovery >,89%). Thus, the method has demonstrated to be suitable for the qualitative and quantitative determination of synephrine, octopamine and tyramine in C. aurantium extracts, for dietary supplement quality control and for food adulteration identification. [source] Nursery rearing of the Asian catfish, Clarias macrocephalus (Günther), at different stocking densities in cages suspended in tanks and pondsAQUACULTURE RESEARCH, Issue 13 2002Ruby F Bombeo Abstract Growth and survival of hatchery-bred Asian catfish, Clarias macrocephalus (Günther), fry reared at different stocking densities in net cages suspended in tanks and ponds were measured. The stocking densities used were 285, 571 and 1143 fry m,3 in tanks and 114, 228 and 457 fry m,3 in ponds. Fish were fed a formulated diet throughout the 28-day rearing period. Generally, fish reared in cages in ponds grew faster, with a specific growth rate (SGR) range of 10.3,14.6% day,1, than those in cages suspended in tanks (SGR range 9,11.3% day,1). This could be attributed to the presence of natural zooplankton (copepods and cladocerans) in the pond throughout the culture period, which served as additional food sources for catfish juveniles. In both scenarios, the fish reared at lower densities had significantly higher SGR than fish reared at higher densities. In the pond, the SGR of fish held at 228 and 457 m,3 were similar to each other but were significantly lower than those of fish held at 114 m,3. The zooplankton in ponds consisted mostly of copepods and cladocerans, in contrast to tanks, in which rotifers were more predominant. Per cent survival ranged from 85% to 89% in tanks and from 78% to 87% in ponds and did not differ significantly among stocking densities and between rearing systems. In conclusion, catfish nursery in cages suspended in tanks and ponds is density dependent. Catfish fry reared at 285 m,3 in tanks and at 114 m,3 in ponds had significantly faster growth rates than fish reared at higher densities. However, the desired fingerling size of 3,4 cm total length for stocking in grow-out culture can still be attained at stocking densities of 457 m,3 in nursery pond and 571 m,3 in tanks. [source] Adaptive significance of food income in European snakes: body size is related to prey energeticsBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2010MARCO A. L. ZUFFI Feeding strategies and diet patterns have been extensively investigated in vertebrates and, more specifically, in snakes. Although it has been hypothesized that prey species may differ in terms of energy content, almost no theoretical or practical study has been carried out to determine actual nutritional values of the common prey types of wild snakes. Our model taxa were a selection of widely distributed and well known European snake species, which have all been studied in depth: approximately 76% of their diet is composed of mammals, reptiles, and insects. We therefore selected a single model species for each of these categories and proceeded with the analyses. Nutritional values were determined using a standard procedure: lizards and mice were richer in proteins than insects (crickets); insects and mice were richer in lipids than lizards, and mice and crickets have a higher energy content than lizards; lizards were rich in ashes. We then applied our experimental results to a selected sample of European terrestrial snakes (11 populations, ten species, seven genera, two families) characterized by different body size (50,160 cm total length) and reproductive strategies (oviparous versus viviparous), aiming to correlate these parameters with patterns of energy income. A direct relationship was found between body mass/body length ratio (BCI, body condition index) and meal energetics: the higher the BCI, the higher was the metabolic requirement, whereas BCI was independent of species or of reproductive system effect. Large-sized snakes thus need a highly diversified and more energy-rich diet than smaller snakes, supporting previous hypotheses. The simple applicability of this method could be of valuable support in further comparative research work, reducing experimental costs and stimulating further ecological, behavioural, and, possibly, phylogenetic comparisons. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 307,317. [source] | |||||||||||||