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Somatic Growth (somatic + growth)
Terms modified by Somatic Growth Selected AbstractsSomatic growth, survival, feed utilization and starvation in European elver Anguilla anguilla (Linnaeus) under two different photoperiodsAQUACULTURE RESEARCH, Issue 5 2009A Rodríguez Abstract The aim of the study was to determine the effect of two photoperiod regimes under artificial conditions on growth performance and survival in the European eel Anguilla anguilla during the transition from glass eel to elver. The fish were held in 12-h-light:12-h-dark (12L:12D) and in continuous darkness (DD) in fed and fast trials lasting 80 days. Fed fish kept in the dark showed higher somatic growth, and a better feed conversion ratio, higher protein and lipid content, with significant differences between treatments. Dark environment increased the survival rate in comparison with fish exposed to 12L:12D, during which eels showed lower survival rates and greater variations in size. Fasted fish suffered loss of body mass in both photoperiods at the end of the experimental phase, but fish exposed to 12L:12D lost more body mass. These results indicate that the photoperiod is a key factor during the glass eel,elver stage, which may contribute to optimizing the early stages of eel culture. [source] Effects of in utero exposure to 2,2,,4,4,,5,5,-hexachlorobiphenyl (PCB 153) on somatic growth and endocrine status in rat offspringCONGENITAL ANOMALIES, Issue 4 2008Kenichi Kobayashi ABSTRACT Exposure to polychlorobiphenyl (PCB) mixtures at an early stage of development has been reported to affect endocrine glands; however, little is known about the precise toxicological properties of individual PCB. The present study was undertaken to determine whether prenatal exposure to 2,2,,4,4,,5,5,-hexachlorobiphenyl (PCB 153), a di- ortho -substituted non-coplanar congener, affects postnatal development in rat offspring. Pregnant Sprague-Dawley rats (Crj: CD (SD) IGS) were given PCB 153 (0, 16, or 64 mg/kg/day) orally from gestational day (GD) 10 through GD 16, and developmental parameters in the male and female offspring were examined. We found no dose-dependent changes in body weight, body length (nose,anus length), tail length, or the weights of kidneys, testes, ovaries and uterus in offspring at 1 or 3 weeks of age. Liver weights were increased in the PCB 153,treated groups, although we observed a significant difference only in males. Anogenital distance was unaffected in the PCB 153,treated groups. We observed a significant dose-dependent decrease in the plasma concentrations of thyroxine and tri-iodothyronine, whereas those of thyroid-stimulating hormone were not significantly changed. In addition, there were no dose-dependent changes in plasma concentrations of growth hormone and insulin-like growth factor-I in any dose group. These findings suggest that prenatal exposure to PCB 153 (GD 10,16, 16,64 mg/kg/day) may alter the thyroid status in rat offspring to some extent without affecting somatic growth or its related hormonal parameters. [source] Reproduction in three species of rainbowfish (Melanotaeniidae) from rainforest streams in northern Queensland, AustraliaECOLOGY OF FRESHWATER FISH, Issue 2 2001B. J. Pusey Abstract , The reproductive biology of three species of rainbowfish (Melanotaeniidae) in northeastern Australian rainforest streams was investigated. Two species, Melanotaenia eachamensis and Cairnsichthys rhombosomoides are endemic to the area, whereas the third, M. splendida splendida, is more widespread. The species were all highly fecund, producing many hundreds of eggs between 1.10 and 1.24 mm in diameter. Melanotaenia eachamensis was the most fecund, produced the largest eggs of the three species, and consequently exhibited the greatest maternal investment (as measured by gonadosomatic index). The majority of reproductive effort occurred during the dry season, although reproductively active fish were present year-round for each of the species, but particularly so for M. s. splendida and C. rhombosomoides. No evidence for a role by temperature or photoperiod as environmental cues for reproduction was found, and it was suggested that gonad development was strongly tied to somatic growth. The concentration of reproduction to the dry season ensures that larvae are produced during a period of relatively stable and benign physical conditions. Comparison of temporal changes in gonadosomatic index values suggest that the spawning season of M. eachamensis, which occurs in high-elevation streams, is more restricted and commences about 1 month earlier than either other species. A similar phenology was observed for the M. s. splendida population found at high elevation and highlights the potential for spatial differences in stream productivity to influence life history., [source] Trophodynamic modeling of walleye pollock (Theragra chalcogramma) in the Doto area, northern Japan: model description and baseline simulationsFISHERIES OCEANOGRAPHY, Issue 2004ORIO YAMAMURA Abstract An age-structured trophodynamic model was constructed to quantitatively analyze factors affecting post-settlement mortality and growth of walleye pollock (Theragra chalcogramma) in the Doto area, the main nursery ground of the Japan Pacific population. The model included (i) multiple age classes of pollock, (ii) a generic predator, (iii) fisheries, and (iv) major prey of pollock. Major processes considered were (i) recruitment, (ii) bottom-up control of somatic growth, (iii) mortality because of predation, cannibalism and fishing, (iv) size-selective prey selection, (v) temperature-dependent bioenergetics such as conversion efficiency and daily consumption rate, and (vi) production and advective supply of prey. By assuming that pollock select prey based upon both relative abundance and predator,prey size relationships, the model accurately simulated seasonal and ontogenetic variations in the diet. However considering ontogenetic segregation, the model showed that, due to cannibalism, newly recruited fish would be totally consumed within 6 months after settlement. By considering segregation (10% overlap during spring and 0.1% during other seasons), an agreement of diet between the simulation and empirical data averaged 82.7% for the different seasons and fish sizes. Euphausiids, the most important prey of pollock, suffered the highest predation impact (22.2 ± 5.3 WWg m,2 yr,1) exceeding annual production in the model domain (17.2 ± 0.1 WWg m,2 yr,1), indicating that an advective supply of prey is necessary to support the pollock population. The daily ration of pollock during spring and summer averaged at 1.2 and 0.6% BW day,1 for small (,200 mm) and large (>200 mm) pollock, respectively; this daily ration was reduced by half during autumn and winter. [source] Predator-released compounds, ambient temperature and competitive exclusion among differently sized Daphnia speciesFRESHWATER BIOLOGY, Issue 4 2006JACOBUS VIJVERBERG Summary 1. We studied the effects of fish water and temperature on mechanisms of competitive exclusion among two Daphnia species in flow-through microcosms. The large-bodied D. pulicaria outcompeted the medium sized D. galeata × hyalina in fish water, but not in the control treatment. Daphnia galeata × hyalina was competitively displaced 36 days earlier at 18 °C than at 12 °C. 2. It is likely that the high phosphorus content of fish water increased the nutritional value of detrital seston particles by stimulating bacterial growth. Daphnia pulicaria was presumably better able to use these as food and hence showed a more rapid somatic growth than its competitor. This led to very high density of D. pulicaria in fish water, but not in the controls. The elevated D. pulicaria density coincided with high mortality and reduced fecundity in D. galeata × hyalina, resulting in competitive displacement of the hybrid. 3. It is clear that the daphnids competed for a limiting resource, as grazing caused a strong decrease in their seston food concentration. However, interference may also have played a role, as earlier studies have shown larger Daphnia species to be dominant in this respect. The high density of large-bodied D. pulicaria in fish water may have had an allelopathic effect on the hybrid. Our data are inconclusive with respect to whether the reached seston concentration was below the threshold resource level (R*) of the hybrid, where population growth rate and mortality exactly balance, as it would be set in the absence of interference, or whether interference actually raised the hybrid's R* to a value above this equilibrium particle concentration. 4. Our results do clearly show that fish-released compounds mediated competitive exclusion among zooplankton species and that such displacement occurred at a greatly enhanced rate at an elevated temperature. Fish may thus not only structure zooplankton communities directly through size-selective predation, but also indirectly through the compounds they release. [source] Ontogenetic Shifts in the Ability of the Cladoceran, Moina macrocopa Straus and Ceriodaphnia cornuta Sars to Utilize Ciliated Protists as Food SourceINTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 3 2008Ram Kumar Abstract The ontogenetic diet shifts and age specific ability of the two cladoceran species Moina macrocopa and Ceriodaphnia cornuta to derive energy from ciliated protists have been investigated in laboratory. The postembryonic developmental rates and life table demography (longevity, age and size at first reproduction, fecundity and intrinsic rate of natural increase) of the cladocerans have been elucidated on algae (Chlorella vulgaris) and the ciliated protists (Tetrahymena pyriformis, Colpoda (c.f.) steini) as food. For either of the cladoceran, the somatic growth rate and average body size at first reproduction were higher with algal diet. During initial stages of development (0,5 days), either cladoceran realized higher rate of somatic growth on algal diet, subsequently ciliated protists supported significantly higher growth rate than the alga. Algal and ciliate diets did not differ in maximum body size (C. cornuta: 539,554 ,m; M. macrocopa: 1274.8,1309 ,m) reached by either of the cladocerans. The maximum body sizes were larger than size at first reproduction with either of the ciliated protists, however, with algal diet the maximum body sizes did not differ from the size at first reproduction in each case. In case of C. cornuta the generation time (20.5 ± 0.3 days on ciliate; 15.6 ± 0.17 days on algal diet), reproductive rates (net reproductive rate: 20.05 ± 3.2 on ciliate; 15.5 ± 1.2 on algal diet), and average life expectancy at hatching (27 ± 0.8 days on ciliate; 22.7 ± 0.71 days on alga) were higher, whereas the size at first reproduction (482 ,m on ciliate; 521 ,m on alga) was smaller with the ciliate than with an algal diet. The algal and the ciliate diets did not differ in survival (life expectancy at hatching: 9.2 ± 0.7 days) and fecundity (NRR: 23.6 ± 2.4) for M. macrocopa. The two ciliates used in the experiment did not differ in their performance as food source for either cladoceran species. Our results suggest that both the cladoceran species are able to utilize smaller ciliate (e.g., T. pyriformis, C. (c.f.) steini) as food; however with differential ability to derive energy from the ciliate diet and this ability is size and age structured in both cases. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Restricted fish feeding reduces cod otolith opacityJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2 2008H. Høie Summary The purpose of this work was to examine the effect of reduced feeding and constant temperature on cod otolith opacity. Three groups of juvenile cod were given restricted food rations at different times for 4 months, resulting in depressed somatic growth. Otolith opacity was measured on pictures of the otolith sections. The otolith carbonate deposited during the experimental period was generally opaque compared to the more translucent otolith material deposited prior to and after the experimental period, when the fish were kept in a pond and in sea-cages at higher temperatures. Large variations in otolith opacity were found between individual fish both within groups and between groups. In two of the three groups significantly more translucent otolith material was deposited in response to reduced feeding. Our results show that variations in feeding and hence fish growth resulted in variation in otolith opacity, but the effect was minor compared to that of variations in ambient temperature. The combined influence of these effects, which both act on fish metabolism, are most likely controlling the seasonal opacity changes observed in wild fish. Our results help explain the variations seen in fish at constant temperatures. [source] White muscle 20S proteasome activity is negatively correlated to growth rate at low temperature in the spotted wolffish Anarhichas minorJOURNAL OF FISH BIOLOGY, Issue 7 2010S. G. Lamarre The effect of temperature and mass on specific growth rate (G) was examined in spotted wolffish Anarhichas minor of different size classes (ranging from 60 to 1500 g) acclimated at different temperatures (4, 8 and 12° C). The relationship between G and 20S proteasome activity in heart ventricle, liver and white muscle tissue was then assessed in fish acclimated at 4 and 12° C to determine if protein degradation via the proteasome pathway could be imposing a limitation on somatic growth. Cardiac 20S proteasome activity was not affected by acclimation temperature nor fish mass and had no correlation with G. Hepatic 20S proteasome activity was higher at 12° C but did not show any relationship with G. Partial correlation analysis showed that white muscle 20S proteasome activity was negatively correlated to G (partial Pearson's r = ,0·609) but only at cold acclimation temperature (4° C). It is suggested that acclimation to cold temperature involves compensation of the mitochondrial oxidative capacity which would in turn lead to increased production of oxidatively damaged proteins that are degraded by the proteasome pathway and ultimately negatively affects G at cold temperature. [source] The effect of temperature and somatic growth on otolith growth: the discrepancy between two clupeid species from a similar environmentJOURNAL OF FISH BIOLOGY, Issue 3 2006D. P. Fey Otolith growth rates of the early life stages of herring Clupea harengus (n= 472) and smelt Osmerus eperlanus (n= 348) collected in the Vistula Lagoon (Baltic Sea) during 1997,1999 were analysed. The larvae and early juveniles were not only collected in the same geographical area they were also of the same size (range 15,43 mm standard length, LS), similar ages and were collected during the same seasons (May to July). Although the two clupeid species experienced very similar environmental conditions, there were significant discrepancies in the analysed relationships. The otolith growth of larval and juvenile smelt was very strongly related to somatic growth while temperature had a minor effect. In herring, the effect of somatic growth, although clearly visible and statistically highly significant, was of less importance than temperature. Furthermore, variation in the otolith size and LS relationship was affected by temperature and somatic growth in both species, but the variance of otolith size at LS was higher for herring than for smelt. Although growth backcalculation from otoliths can presently be recommended as an appropriate method for use with both smelt and herring (despite possibly lower precision and accuracy with the latter), other methods referring directly to short-term increment width changes (e.g. marginal increment analysis) are recommended for smelt but not for herring. [source] The effect of elevated oocyte triiodothyronine content on development of rainbow trout embryos and expression of mRNA encoding for thyroid hormone receptorsJOURNAL OF FISH BIOLOGY, Issue 1 2004J. C. Raine The ability of developing rainbow trout Oncorhynchus mykiss embryos to compensate for elevated oocyte triiodothyronine (T3) content and whether elevation of oocyte T3 content within a physiologically meaningful range affects growth rates of the embryo or the expression of genes encoding for thyroid hormone receptors ,(TR,) and ,(TR,) were examined. Oocytes were immersed in ovarian fluid alone (control) or T3 -enriched ovarian fluid prior to fertilization and water hardening, to induce a dose-dependant increase in oocyte T3 content of c. 3 (control), c. 30 (LT3) or c. 110 ng egg,1(HT3). To examine the interaction of embryo somatic growth with altered thyroid state more effectively, the embryos were reared at two ambient temperatures (8·5 and 5·5°C ) to induce different growth rates. A significant decline in whole embryo T3 content was measured in the T3 -treatment groups reared at both water temperatures by 3 weeks post-fertilization (dpf), and may have reflected the action of outer ring monodeiodinase, which was present in microsomes prepared from embryos 23 dpf. Whole embryo T3 levels in the HT3 group, however, remained higher than controls until phase 2 of development [the onset of endogenous thyroid hormone (TH) release]. This suggested that the embryos exerted some control over their response to exogenous TH, but that there was a limit to the level of control exerted by the embryonic tissues. Reverse transcriptase-polymerase chain reaction (RT-PCR) revealed the presence of mRNA encoding for the two TR isoforms as early as 26 dpf, and quantitative real-time RT-PCR (qPCR) was used to examine the effect of elevated oocyte T3 content on the expression of these TR genes in embryos raised at 8·5 and 5·5° C, and sampled at similar developmental stages prior to the onset of embryonic TH synthesis, to ensure that the oocyte T3 was the only source of TH exposure to the embryo. There was a suppression of the TR, gene expression in the control 5·5° C group relative to the control 8·5° C group. In addition, both TR, and TR, mRNA accumulation was lower, relative to the controls, in the LT3 treatment group reared at 8·5° C suggesting a suppressive effect of the lower level of T3 treatment on the TR gene expression. Conversely, there were no differences from controls in the HT3 treatment group, possibly indicating that this level of exposure overrides the down-regulating capacity of the embryo. Similar patterns were seen for TR, and TR, mRNA accumulation in embryos reared at 5·5° C, but because of the temperature suppressed level of TR, mRNA in the controls, significant affects of the LT3 treatment were only found for TR,. There were no measurable effects of T3 treatment on oocyte fertility or embryo somatic growth for either temperature treatment group, nor was somatic growth hormone content (measured only in the 8·5° C treatment group) apparently related to in ovo T3 levels. The results suggest that altered in ovo T3 levels, within the ranges used here, do not induce marked affects on embryo development, probably because of the ability of the embryo to maintain the integrity of its TH milieu. [source] Energy allocation in juvenile sablefish: effects of temperature, ration and body sizeJOURNAL OF FISH BIOLOGY, Issue 3 2004S. M. Sogard The lipid deposition of juvenile sablefish Anoplopoma fimbria was examined, in particular, the changes in allocation over time. Growth rates of early juveniles (initial size 36,50 mm total length, LT) were manipulated using two temperatures (10 and 20° C) and two rations (ad libitum and 3,4% body mass day,1). Fish LT, mass and lipid content were measured every 3 weeks for 15 weeks. Irrespective of treatment, the relationship of total lipid content with body size was clearly hyperallometric; small juveniles allocated relatively more energy to growth and less to lipid storage than large juveniles. After adjusting for the influence of body size, temperature and ration significantly influenced body composition but these effects varied over the course of the experiment. In the first 3 week time period, fish on the high ration, high temperature treatment had reduced lipid storage relative to other treatments, but in all subsequent time periods their lipid concentrations were similar to or higher than those of fish on other treatments. In contrast, fish held at low rations and low temperatures initially had average levels of lipid concentration, but after 6 weeks their levels were lower than other treatments. Estimation of allocation to lipid storage over time (proportion of dry mass increase comprised of lipid) suggested that fish in all of the treatments were approaching an asymptotic level of lipid concentration (c. 50,60% of dry mass) but with different rates of lipid increase. Within a treatment, it was predicted that individual differences in allocation would result in trade-offs between somatic growth and storage. This trade-off was evident only for fish held on low rations at low temperatures. In contrast, fish held on high rations at high temperatures exhibited the opposite pattern of a positive correlation between somatic growth and storage. These results suggest that lipostatic regulation of appetite is unlikely in juvenile sablefish. When resources are unlimited, this species appears to adopt a maximizing strategy for both somatic growth and lipid accumulation. [source] Effects of different food restrictions on somatic and otolith growth in Nile tilapia reared under controlled conditionsJOURNAL OF FISH BIOLOGY, Issue 5 2002A. M. Massou .Nile tilapia Oreochromis niloticus, initial age 12 days, were given an unrestricted (NR) or restricted (R) ration over 93 days which resulted in fish of very different sizes although the body condition factor (K) and the viscero-somatic index (IV) remained almost unchanged. In a second stage (64 days) each group (NR & R) was divided into three subgroups that were subjected to 0 (NR0, R0), 15 (NR15, R15) and 30 (NR30, R30) days of food restriction, respectively. The impact of the different treatments on the somatic growth during the second stage of the experiment had an effect, with a highly significant difference between the mean ± S.D. masses (MT) in the different subgroups (NR0= 115.0 ± 26.6 g; NR15 = 94.8 ± 24.9 g; NR30 = 56.3 ± 28 g; R0 = 76.4 ± 20.1 g; R15 = 72.l ± 17.6 g; R30 = 43.6 ± 17.2 g). Similarly, K and IV decreased. Irrespective of the initial feeding condition, the width of the otolith microincrements started to decrease at the end of the first or second day of restricted feeding. In the subgroups given a restricted food ration for 30 days (NR30 and R30), this decrease reached a plateau at about day 30, which was maintained even when the restriction had ended. This slowed growth did not lead to any marked halt in microincrement formation, since there were no significant differences (ANOVA; P>0.05) in the numbers of increments counted in the various subgroups. The results show that in 153 day old fish, a period of severe food restriction, even if prolonged (15 to 30 days), had no influence on the timing of the laying down of microincrements but only affected their growth. [source] Observations on the histochemistry and ultrastructure of regenerating caudal epidermis of the tuatara Sphenodon punctatus (Sphenodontida, Lepidosauria, Reptilia)JOURNAL OF MORPHOLOGY, Issue 2 2003Lorenzo Alibardi Abstract Study of the histology, histochemistry, and fine structure of caudal epidermal regeneration in Sphenodon punctatus through restoration of a scaled form reveals that the processes involved resemble those known in lizards. Following establishment of a wound epithelium (WE), subjacent scale neogenesis involves epidermal downgrowths into the dermis. Although the process is extremely slow, and most new scales do not overlap, their epidermal coverings reestablish epidermal generation (EG) formation. As in lizards, the flat, ,-keratogenic, WE cells contain lipids as revealed by their affinity for Sudan III. A few mucous cells that store large PAS-positive mucus-like granules also occur in WE. During differentiation of WE cells, among the bundles of 70-nm tonofilaments are many lamellar bodies (LBs) and mucous granules (MGs) that discharge their contents into the cytoplasm and extracellular spaces producing a strongly PAS-positive keratinized tissue. Richness of epidermal lipids coexistent with mucus is a primitive characteristic for amniote vertebrates, probably related to functions as a barrier to cutaneous water loss (CWL). As scale neogenesis begins, beneath the superficial WE appear 3,5 layers of irregularly shaped cells. These contain tonofilament bundles surrounded by small, round keratohyalin-like granules (KHLGs) and a keratinized matrix with ,-keratin packets and a 3,5-nm thick keratin granulation. This mixture of ,- and ,-keratogenic capacities resembles that seen in the innermost cells of a normal tuatara epidermal generation. As in the latter, but in contrast to both normal and regenerating lizard epidermis, no definable shedding complex with interdigitating clear layer and oberhautchen cells occurs (Alibardi and Maderson, 2003). The tortuous boundaries, and merging ,-keratin packets, identify subjacent keratinizing cells as precursors of the typical stratified, squamous ,-layer seen in long-term regenerated caudal skin wherein the entire vertical sequence of epidermal layers resembles that of normal scales. The sequence of events in caudal epidermal regeneration in S. punctatus resembles that documented for lizards. Observed differences between posttrauma scale neogenesis and scale embryogenesis are responses to functional problems involved in, respectively, restoring, or forming, a barrier to CWL while accommodating rapid somatic growth. J. Morphol. 256:134,145, 2003. © 2003 Wiley-Liss, Inc. [source] Actions and Interactions of Alcohol and Insulin-Like Growth Factor-1 on Female Pubertal DevelopmentALCOHOLISM, Issue 11 2009W. Les Dees Alcohol (ALC) is a drug that is capable of disrupting reproductive function in adolescent humans, as well as immature rhesus monkeys and rats. Critical to determining the mechanism(s) of the effects of ALC on the pubertal process is to have a better understanding of the important events involved in the initiation of puberty. For years it has been hypothesized that there may be metabolic signals capable of linking somatic growth to the activation of the reproductive system at the time of puberty. In recent years it has been shown that insulin-like growth factor-1 (IGF-1) is one such signal that plays an early role in the pubertal process. In this review, we will describe the actions and interactions of ALC and IGF-1 on molecular and physiological processes associated with pubertal development. [source] Energetic costs, underlying resource allocation patterns, and adaptive value of predator-induced life-history shiftsOIKOS, Issue 2 2008Karsten Rinke We studied costs and benefits of life history shifts of water fleas (genus Daphnia) in response to infochemicals from planktivorous fish. We applied a dynamic energy budget model to investigate the resource allocation patterns underlying the observed life history shifts and their adaptive value under size selective predation in one coherent analysis. Using a published data set of life history shifts in response to fish infochemicals we show that Daphnia invests less energy in somatic growth in the fish treatment. This observation complies with theoretical predictions on optimal resource allocation. However, the observed patterns of phenotypic plasticity cannot be explained by changes in resource allocation patterns alone because our model-based analysis of the empirical data clearly identified additional bioenergetic costs in the fish treatments. Consequently, the response to fish kairomone only becomes adaptive if the intensity of size selective predation surpasses a certain critical level. We believe that this is the first study that puts resource allocation, energetic costs, and adaptive value of predator induced life-history shifts , using empirical data , into one theoretical framework. [source] Longitudinal changes in lung function and somatic growth in children with sickle cell disease,PEDIATRIC PULMONOLOGY, Issue 6 2007Anastassios C. Koumbourlis MD Abstract Background We studied the changes in the patterns of lung function and somatic growth over time in children and adolescents (10.6,±,3.5 years at first test) with hemoglobin SS (Hb-SS) sickle cell disease (SCD). Methods Lung function and somatic growth were measured twice with an interval of 42.3,±,23.3 months in 45 children (25 females and 20 males) with Hb-SS SCD. Results The lung volumes slightly decreased but remained borderline normal in both tests. All spirometric indices were within the normal range but significantly decreased (P,<,0.001) at the time of the second test indicating development of lower airway obstruction (forced expiratory volume in the first second (FEV1): 87,±,21 vs. 80,±,15; FEV1/forced vital capacity (FVC): 89,±,7 vs. 85,±,6; FEF25,75: 89,±,32 vs. 76,±,24). "Normal" pattern of lung function was initially found in 56% of the patients, but in only 29% in the second test. In contrast, those with "obstructive" pattern increased from 22 to 44%, and those with "restrictive" pattern from 22 to 27%. There was no association between history of asthma and pattern of lung function. "Normal" Body Mass Index (BMI) was found in 64% of the patients, whereas 13% had "High" BMI and 22% "Low" BMI. The two latter patterns were associated with abnormal lung function but only patients with normal BMI showed actual decline overtime. Conclusion SCD is characterized by a predominantly obstructive pattern of lung function that increases in prevalence over time. There was no apparent causal relationship between the pattern of somatic growth and the pattern of lung function. Pediatr Pulmonol. 2007; 42:483,488. © 2007 Wiley-Liss, Inc. [source] Growth patterns in adverse environmentsAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 5 2007Noël Cameron The triple-logistic pattern of human growth in linear dimensions is probably one of the most recognizable models within human biology. The fact that postnatal somatic growth occurs in three phases (infancy, childhood, adolescence) creates opportunities for the individual expression of this genetically directed, but environmentally modified, phenomenon. The impact of the environment works to alter the duration and intensity of critical stages within the total process resulting in individual patterns that can differ radically from the general pattern. However, the constancy of the general pattern is so fixed that its presence in children is taken as a reflection of good health. Departures from that pattern are recognized as reflecting ill health. While the cessation of growth in response to an acute attack is uniformly dramatic, the gradual response to chronic adverse stimuli is less easily predicted and interpreted. For example, in chronic scenarios the loss of centile position that precedes the eventual establishment of normal increments can be viewed as either a poor or a good growth response, as either maladaptive or adaptive, as either poor health or good health. This article reviews such growth patterns in urban South African children exploring the relationship between environment and growth outcome. Am. J. Hum. Biol., 2007. © 2007 Wiley-Liss, Inc. [source] Lung Transplantation in Infants and Toddlers from 1990 to 2004 at St. Louis Children's HospitalAMERICAN JOURNAL OF TRANSPLANTATION, Issue 4 2009A. Elizur In a retrospective, single-center cohort study, outcomes of infants and toddlers undergoing lung transplant at St. Louis Children's Hospital between 1990 and 2004 were compared to older children. Patients with cystic fibrosis (exclusively older children) and those who underwent heart,lung, liver,lung, single lung or a second transplantation were excluded from comparisons. One hundred nine lung transplants were compared. Thirty-six were in infants <1 year old, 26 in toddlers 1,3 years old and 47 in children >3 years old. Graft survival was similar for infants and toddlers (p = 0.35 and p = 0.3, respectively) compared to children over 3 years old at 1 and 3 years after transplant. Significantly more infants (p < 0.0001 and p = 0.003) and toddlers (p = 0.002 and p = 0.03) were free from acute rejection and bronchiolitis obliterans compared to older patients. While most infants and toddlers had only minimal lung function impairment, and achieved normal to mildly delayed developmental scores, somatic growth remained depressed 5 years after transplant. Lung transplantation in infants and young children carries similar survival rates to older children and adults. Further insights into the unique immunologic aspects of this group of patients may elucidate strategies to prevent acute and chronic rejection in all age groups. [source] Cultivation of Paracentrotus lividus (Echinodermata: Echinoidea) on extruded feeds: digestive efficiency, somatic and gonadal growthAQUACULTURE NUTRITION, Issue 2 2001Spirlet This study assessed the use of extruded feeds, in the form of pellets, for the growing of echinoid Paracentrotus lividus within a closed-culture system. Two feed types, one with soya-bean protein, the other with both soya-bean and fish protein were compared with dried Lessonia sp. and fresh Laminaria sp. as food sources. Pellets present a very high conversion efficiency (about 80%) against about 50% for Laminaria and 35% for Lessonia. However, as pellets are less absorbed, somatic growth (SG) is statistically equivalent for the sea urchins fed with pellets and Laminaria between 2 and 2.2% g soma day,1. Sea urchins fed with pellets produced significantly more gonadal tissue in a shorter time, resulting in a gonadal index (GI) twice higher (6.5%) than Laminaria (3%) in the second month of the experiment. Dry Lessonia does not promote gonadal growth (GG). This study shows that extruded feeds are well assimilated by P. lividus and promote both SG and production of gonadal tissue. [source] An experimental assessment on the effects of photoperiod treatments on the somatic and gonadal growth of the juvenile European purple sea urchin Paracentrotus lividusAQUACULTURE RESEARCH, Issue 7 2010Eimear McCarron Abstract Determining the optimum light conditions for sea urchins reared in land-based systems is vital for the future use and assessment of possible commercial systems of sea urchin farming. The effects of two different light regimes, complete darkness and a long day photoperiod of 16 h light:8 h darkness, on the somatic and gonadal growth of the European sea urchin Paracentrotus lividus (19.5,23.0 mm) was investigated using the commercial UrchinPlatterÔ System over a 6-month period (5 March to 5 September). Hatchery-produced P. lividus were transported to the Aquaculture Fisheries Development Centre (AFDC, University College, Cork UCC). Before arrival at the AFDC, sea urchins were reared on a diet of Laminaria digitata. Females were the predominant species of the animal group, displaying a reproductive Stage III (growing stage) where gametogenesis was commencing. Results show that darkness supports higher somatic growth than the photoperiod treatment. Feeding rates were higher for sea urchins reared under darkness with gonadal growth increasing for both experimental treatments. Individuals reared under darkness had a higher per cent change in gonad index from the initial sample taken at the beginning of the experiment. [source] Somatic growth, survival, feed utilization and starvation in European elver Anguilla anguilla (Linnaeus) under two different photoperiodsAQUACULTURE RESEARCH, Issue 5 2009A Rodríguez Abstract The aim of the study was to determine the effect of two photoperiod regimes under artificial conditions on growth performance and survival in the European eel Anguilla anguilla during the transition from glass eel to elver. The fish were held in 12-h-light:12-h-dark (12L:12D) and in continuous darkness (DD) in fed and fast trials lasting 80 days. Fed fish kept in the dark showed higher somatic growth, and a better feed conversion ratio, higher protein and lipid content, with significant differences between treatments. Dark environment increased the survival rate in comparison with fish exposed to 12L:12D, during which eels showed lower survival rates and greater variations in size. Fasted fish suffered loss of body mass in both photoperiods at the end of the experimental phase, but fish exposed to 12L:12D lost more body mass. These results indicate that the photoperiod is a key factor during the glass eel,elver stage, which may contribute to optimizing the early stages of eel culture. [source] Growth and reproduction of threatened native crucian carp Carassius carassius in small ponds of Epping Forest, south-east EnglandAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 7 2009Ali Serhan Tarkan Abstract 1.The crucian carp Carassius carassius is a species of cyprinid fish native to south-east England, but few studies exist on its growth and reproduction in England, and the species is threatened by introductions of its Asiatic congener, goldfish Carassius auratus. To increase knowledge of the crucian carp as a means of aiding its conservation, the present study assesses the growth (back-calculated length at age, body condition) and reproduction (fecundity, egg size, length and age at maturity) of crucian carp in small ponds of Epping Forest (north-east London, England). 2.Evaluation of growth and reproduction data with published data for populations from northern Europe (i.e. latitude ,50°) suggest that growth is very variable, even within the same area, and that data on reproductive indices, in particular length and age at maturity, are scarce. In England, the length at age trajectory of crucian carp living in sympatry with feral goldfish Carassius auratus did not differ significantly from allopatric crucian carp populations, but crucian carp body condition and relative fecundity (eggs per body weight) were highest, and mean age and standard length at maturity were lowest in sympatry with goldfish. 3.These data suggest that somatic growth and reproductive output may be maximized in crucian carp when confronted by coexistence with feral goldfish. However, the potential impact of goldfish introductions on crucian carp growth and reproduction requires further study, involving a much larger number of crucian carp populations, both in allopatry and sympatry with feral goldfish populations. © Crown copyright 2009. Reproduced with the permission of Her Majesty's stationery Office. Published by John Wiley & Sons, Ltd. [source] Comparisons of age, growth, and maturity between male and female, and diploid and triploid individuals in Carassius auratus from Okinawa-jima Island, JapanAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 7 2009Mikumi Takada Abstract 1.Carassius auratus, a primary freshwater fish with bisexual diploid and unisexual gynogenetic triploid lineages, is distributed widely in and around the Eurasian continent and is especially common in East Asia. East Asian C. auratus diverged genetically to form local endemic populations in different regions, and those distributed in the Ryukyu Archipelago form a local endemic population that can be regarded as an evolutionarily significant unit because of its high phylogenetic independence and evolutionary distinctiveness. Although the evolutionary uniqueness of this population should be conserved, its distribution area and population size are decreasing rapidly, and some island populations are currently considered endangered or already extinct. 2.To develop effective conservation measures to stop the current decline of Ryukyuan C. auratus, ecological data need to be collected. In this study, life history data for a C. auratus population distributed in the Hiji River system were collected by estimating age, growth, and spawning season. 3.The spawning season of C. auratus in the Hiji River extended from March to September, peaking during March,May. Females became sexually mature in their second year, but males reached maturity and were able to spawn as early as in the late spawning season of their year of hatching. Once having reached sexual maturity, males probably continuously stay ripe throughout their life. 4.Sagittal otoliths of C. auratus proved to be useful ageing structures because one annual increment is formed on the sagittal otolith before the spawning season in each year. The oldest fish observed were a 10-year-old female and an 11-year-old male. Females showed faster somatic growth and higher final standard length than males, and a sexual size dimorphism was observed. 5.The standard length at each age class did not differ between diploid and triploid C. auratus, suggesting that triploid growth rates were almost equal to those of diploids. Copyright © 2009 John Wiley & Sons, Ltd. [source] Minimal aberrant behavioral phenotypes of neuroligin-3 R451C knockin miceAUTISM RESEARCH, Issue 3 2008Kathryn K. Chadman Abstract Neuroligin-3 is a member of the class of cell adhesion proteins that mediate synapse development and have been implicated in autism. Mice with the human R451C mutation (NL3), identical to the point mutation found in two brothers with autism spectrum disorders, were generated and phenotyped in multiple behavioral assays with face validity to the diagnostic symptoms of autism. No differences between NL3 and their wildtype (WT) littermate controls were detected on measures of juvenile reciprocal social interaction, adult social approach, cognitive abilities, and resistance to change in a spatial habit, findings which were replicated in several cohorts of males and females. Physical and procedural abilities were similar across genotypes on measures of general health, sensory abilities, sensorimotor gating, motor functions, and anxiety-related traits. Minor developmental differences were detected between NL3 and WT, including slightly different rates of somatic growth, slower righting reflexes at postnatal days 2,6, faster homing reflexes in females, and less vocalizations on postnatal day 8 in males. Significant differences in NL3 adults included somewhat longer latencies to fall from the rotarod, less vertical activity in the open field, and less acoustic startle to high decibel tones. The humanized R451C mutation in mice did not result in apparent autism-like phenotypes, but produced detectable functional consequences that may be interpreted in terms of physical development and/or reduced sensitivity to stimuli. [source] | ||||||||||||||||