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Sample records for survival growth reproduction

  1. Water fleas require microbiota for survival, growth and reproduction.

    Science.gov (United States)

    Sison-Mangus, Marilou P; Mushegian, Alexandra A; Ebert, Dieter

    2015-01-01

    Microbiota have diverse roles in the functioning of their hosts; experiments using model organisms have enabled investigations into these functions. In the model crustacean Daphnia, little knowledge exists about the effect of microbiota on host well being. We assessed the effect of microbiota on Daphnia magna by experimentally depriving animals of their microbiota and comparing their growth, survival and fecundity to that of their bacteria-bearing counterparts. We tested Daphnia coming from both lab-reared parthenogenetic eggs of a single genotype and from genetically diverse field-collected resting eggs. We showed that bacteria-free hosts are smaller, less fecund and have higher mortality than those with microbiota. We also manipulated the association by exposing bacteria-free Daphnia to a single bacterial strain of Aeromonas sp., and to laboratory environmental bacteria. These experiments further demonstrated that the Daphnia-microbiota system is amenable to manipulation under various experimental conditions. The results of this study have implications for studies of D. magna in ecotoxicology, ecology and environmental genomics.

  2. Survival, growth and reproduction of cryopreserved larvae from a marine invertebrate, the Pacific oyster (Crassostrea gigas.

    Directory of Open Access Journals (Sweden)

    Marc Suquet

    Full Text Available This study is the first demonstration of successful post-thawing development to reproduction stage of diploid cryopreserved larvae in an aquatic invertebrate. Survival, growth and reproductive performances were studied in juvenile and adult Pacific oysters grown from cryopreserved embryos. Cryopreservation was performed at three early stages: trochophore (13±2 hours post fertilization: hpf, early D-larvae (24±2 hpf and late D-larvae (43±2 hpf. From the beginning (88 days at the end of the ongrowing phase (195 days, no mortality was recorded and mean body weights did not differ between the thawed oysters and the control. At the end of the growing-out phase (982 days, survival of the oysters cryopreserved at 13±2 hpf and at 43±2 hpf was significantly higher (P<0.001 than those of the control (non cryopreserved larvae. Only the batches cryopreserved at 24±2 hpf showed lower survival than the control. Reproductive integrity of the mature oysters, formely cryopreserved at 13±2 hpf and 24±2 hpf, was estimated by the sperm movement and the larval development of their offspring in 13 crosses gamete pools (five males and five females in each pool. In all but two crosses out of 13 tested (P<0.001, development rates of the offspring were not significantly different between frozen and unfrozen parents. In all, the growth and reproductive performances of oysters formerly cryopreserved at larval stages are close to those of controls. Furthermore, these performances did not differ between the three initial larval stages of cryopreservation. The utility of larvae cryopreservation is discussed and compared with the cryopreservation of gametes as a technique for selection programs and shellfish cryobanking.

  3. The influence of thymol+DMSO on survival, growth and reproduction of Bradybaena similaris (Mollusca: Bradybaenidae

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    Paula Ferreira

    2011-04-01

    Full Text Available Bradybaena similaris (Férussac, 1821, commonly known as the Asian trampsnail, is a terrestrial snail native to Asia, introduced in other regions of the world. In Brazil, populations of this land snail are distributed from the state of Amapá in the North to Rio Grande do Sul in the South. This species acts as an intermediate host for parasites and is a difficult-to-control agricultural pest as well, causing great losses to crops and ornamental plant cultivation. This land snail is easily reared in the laboratory and has been successfully used as a biological model in studies that aim at verifying molluscicidal effects of plant extracts. Several studies have demonstrated that B. similaris, like many other species of land and freshwater snails, is physiologically adapted to survival over transitory unfavorable environmental conditions. Moreover, this species seems to have a life history strategy characterized by a short life span and a maximal opportunistic reproductive effort during transient favorable periods. Such biological features may potentially lead to the inefficacy of control attempts and, simultaneously, make this species able to repopulate sites previously treated with biocides. For this reason, studies that aim at verifying the effect of molluscicides on the reproduction, growth and survival of molluscs are greatly required. Molluscicides of plant origin may represent a safe and effective way of controlling these animals. Thymol is a substance of plant origin which has bactericidal, fungicidal and anti-inflammatory properties and has been presented as a promissory biocide of mollusc species. The aim of this work was to assess the molluscicidal property of thymol in combination with DMSO against eggs and adults of B. similaris. During 120 days, we evaluated the effect of thymol+DMSO at different concentrations (2.5 g/L and 5 g/L on the hatching success, hatchling survival, growth and reproduction of B. similaris under laboratory

  4. Effects of Snail Density on Growth, Reproduction and Survival of Biomphalaria alexandrina Exposed to Schistosoma mansoni

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    T. D. Mangal

    2010-01-01

    Full Text Available The effects of snail density on Biomphalaria alexandrina parasitized with Schistosoma mansoni were investigated. Laboratory experiments were used to quantify the impact of high density on snail growth, fecundity, and survival. Density-dependent birth rates of snails were determined to inform mathematical models, which, until now, have assumed a linear relationship between density and fecundity. The experiments show that the rate of egg-laying followed a negative exponential distribution with increasing density and this was significantly affected by exposure to parasitic infection. High density also affected the weight of snails and survival to a greater degree than exposure to parasitic infection. Although snail growth rates were initially constrained by high density, they retained the potential for growth suggesting a reversible density-dependent mechanism. These experimental data can be used to parameterise models and confirm that snail populations are regulated by nonlinear density-dependent mechanisms.

  5. Successful survival, growth, and reproductive potential of quagga mussels in low calcium lake water: is there uncertainty of establishment risk?

    Directory of Open Access Journals (Sweden)

    Clinton J. Davis

    2015-11-01

    Full Text Available The risk of quagga mussel (Dreissena rostriformis bugensis Andrusov 1897 establishment into water-bodies of the western US has expanded the geographic concern regarding the ecological and economic impacts this species will have in aquatic ecosystems. Thresholds based on calcium concentrations, an element critical for mussel growth and physiology, have been used as a primary predictor of quagga mussel establishment success to aid management decisions. We evaluated the invasion potential of quagga mussels in low calcium waters using laboratory experiments to compare the survival, growth and reproductive potential of adult mussels held for 90 days at low (9 and 12 ppm, moderate (15 to 32 ppm and high (72 ppm calcium water concentrations. In conjunction with adult experiments, veliger stage survival, growth and settlement were evaluated under similar low, moderate, and high calcium water treatments. Adult mussels survived, grew and showed reproductive potential in low calcium water (12 ppm. Veligers were also able to survive, grow and settle in low calcium water. Higher levels of natural seston biomass appeared to improve adult mussel life history performance in low calcium water. Survival curve analysis predicted that 99% adult mortality could occur in 15 ppm could have adults surviving more than a year. The results from these bioassays provide further evidence that quagga mussels have higher risk of establishment in low calcium lakes if habitats exist that have slightly elevated calcium. These results should help emphasize the vulnerability of water-body in the 12 to 15 ppm calcium range that could potentially be at risk of establishing sustainable quagga mussel populations. Furthermore, these results provide insights into the uncertainty of using a single parameter in assigning establishment risk given the complexity of variables in specific water-bodies that influence life history performance of introduced species.

  6. Successful survival, growth, and reproductive potential of quagga mussels in low calcium lake water: is there uncertainty of establishment risk?

    Science.gov (United States)

    Davis, Clinton J; Ruhmann, Emma K; Acharya, Kumud; Chandra, Sudeep; Jerde, Christopher L

    2015-01-01

    The risk of quagga mussel (Dreissena rostriformis bugensis Andrusov 1897) establishment into water-bodies of the western US has expanded the geographic concern regarding the ecological and economic impacts this species will have in aquatic ecosystems. Thresholds based on calcium concentrations, an element critical for mussel growth and physiology, have been used as a primary predictor of quagga mussel establishment success to aid management decisions. We evaluated the invasion potential of quagga mussels in low calcium waters using laboratory experiments to compare the survival, growth and reproductive potential of adult mussels held for 90 days at low (9 and 12 ppm), moderate (15 to 32 ppm) and high (72 ppm) calcium water concentrations. In conjunction with adult experiments, veliger stage survival, growth and settlement were evaluated under similar low, moderate, and high calcium water treatments. Adult mussels survived, grew and showed reproductive potential in low calcium water (12 ppm). Veligers were also able to survive, grow and settle in low calcium water. Higher levels of natural seston biomass appeared to improve adult mussel life history performance in low calcium water. Survival curve analysis predicted that 99% adult mortality could occur in 15 ppm could have adults surviving more than a year. The results from these bioassays provide further evidence that quagga mussels have higher risk of establishment in low calcium lakes if habitats exist that have slightly elevated calcium. These results should help emphasize the vulnerability of water-body in the 12 to 15 ppm calcium range that could potentially be at risk of establishing sustainable quagga mussel populations. Furthermore, these results provide insights into the uncertainty of using a single parameter in assigning establishment risk given the complexity of variables in specific water-bodies that influence life history performance of introduced species.

  7. Survival, reproduction, growth, and parasite resistance of aquatic organisms exposed on-site to wastewater treated by advanced treatment processes.

    Science.gov (United States)

    Schlüter-Vorberg, Lisa; Knopp, Gregor; Cornel, Peter; Ternes, Thomas; Coors, Anja

    2017-05-01

    Advanced wastewater treatment technologies are generally known to be an effective tool for reducing micropollutant discharge into the aquatic environment. Nevertheless, some processes such as ozonation result in stable transformation products with often unknown toxicity. In the present study, whole effluents originating from nine different steps of advanced treatment combinations were compared for their aquatic toxicity. Assessed endpoints were survival, growth and reproduction of Lumbriculus variegatus, Daphnia magna and Lemna minor chronically exposed in on-site flow-through tests based on standard guidelines. The treatment combinations were activated sludge treatment followed by ozonation with subsequent filtration by granular activated carbon or biofilters and membrane bioreactor treatment of raw wastewater followed by ozonation. Additionally, the impact of treated wastewater on the immune response of invertebrates was investigated by challenging D. magna with a bacterial endoparasite. Conventionally treated wastewater reduced reproduction of L. variegatus by up to 46%, but did not affect D. magna and L. minor with regard to survival, growth, reproduction and parasite resistance. Instead, parasite susceptibility was significantly reduced in D. magna exposed to conventionally treated as well as ozonated wastewater in comparison to D. magna exposed to the medium control. None of the three test organisms provided clear evidence that wastewater ozonation leads to increased aquatic toxicity. Rather than to the presence of toxic transformation products, the affected performance of L. variegatus could be linked to elevated concentrations of ammonium and nitrite that likely resulted from treatment failures. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Effects of various metals on survival, growth, reproduction, and metabolism of Daphnia magna

    Energy Technology Data Exchange (ETDEWEB)

    Biesinger, K E; Christensen, G M

    1972-01-01

    The toxicities of various metals to Daphnia magna were evaluated on the basis of a 48-hr 50% lethal concentration (lc50) 3-week 16% reproductive impairment concentrations (In micrograms per liter) for the metal ions tested were: Na(I), 680,000; Ca(II), 116,000; Mg(II), 82,000; K(I), 53,000; Sr(II), 42,000; Ba(II), 5,800; Fe(III), 4,380; Mn(II), 4,100; As(V), 520; Sn(II), 350; Cr(III), 330; Al(III), 320; Zn(II), 70; Au(III), 60; Ni(II), 30; Pb(II), 30; Cu(II), 22; Pt(IV), 14; Co(II), 10; Hg(II), 3.4; and Cd(II), 0.17. At mental concentrations permitting survival but impairing reproduction, daphnids weighed less than control animals. Amounts of total protein and glutamic oxalacetic transaminase activity varied with the different metals. The negative logarithm of the solubility product constant 8 pksp of the metal sulfides, electronegativity, and the logarithm of the equilibrium constant (log keg) of the metal-ATP complex were positively correlated with toxicity to D. magna. Other physicochemical properties were considered, but no additional correlations were found.

  9. Effects of decabromodiphenyl ether (BDE-209) on the avoidance response, survival, growth and reproduction of earthworms (Eisenia fetida).

    Science.gov (United States)

    Xie, Xianchuan; Qian, Yan; Wu, Yingxin; Yin, Jun; Zhai, Jianping

    2013-04-01

    The effects of decabromodiphenyl ether (BDE-209) on avoidance response, survival, growth, and reproduction of earthworms (Eisenia fetida) were investigated under laboratory conditions using natural and artificial soils as substrate. Results showed that no significant avoidance response was observed when earthworms were exposed to 0.1-1000 mg/kg of BDE-209 for 48 h. After 28-days exposure, no significant effects on survival and growth of adult earthworms was induced by 0.1-1000 mg/kg of BDE-209 indicating the Lowest Observed Effect Level (LOEL) of BDE-209 on their survival and body weight was more than 1000 mg/kg. Except for a significant decrease in the number of juveniles per hatched cocoon in artificial soils at 1000 mg/kg of BDE-209, no significant effects on reproductive parameters (e.g. cocoon production per earthworms, weight per cocoon and cocoon hatchability) were observed. These results suggest that adult earthworms have a strong tolerance for BDE-209 exposure in soils, but a potential toxicity does exist for earthworm embryos or juveniles. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Effects of functionalized fullerenes on bifenthrin and tribufos toxicity to Daphnia magna: Survival, reproduction, and growth rate.

    Science.gov (United States)

    Brausch, Kathryn A; Anderson, Todd A; Smith, Philip N; Maul, Jonathan D

    2010-11-01

    Incorporation of carbon nanomaterials into industrial and consumer products is increasing, yet their impact on aquatic ecosystems alone and in chemical mixtures is largely unknown. Carbon nanomaterials may be found in the aquatic environment as mixtures with pesticides because of their proposed use in agriculture as smart delivery systems and nanosensors. The interaction effects of a functionalized fullerene ([1,2-methanofullerene C₆₀]-61-carboxylic acid) (fC₆₀) at 52.8 µg/L and the hydrophobic pesticides bifenthrin and tribufos were examined. The test organism was Daphnia magna, and response variables included 48-h survival, reproduction (bifenthrin, 70-d; tribufos, 21-d), and 10-d growth. Both pesticides reduced D. magna survival and reproduction (p bifenthrin acute toxicity but did not significantly affect chronic endpoints or growth (p > 0.05). Median lethal concentrations (LC50s), median inhibition concentrations (IC50s) for days surviving, and IC50s for reproduction were 0.86, 0.55, and 0.49 µg/L for bifenthrin; 0.22, 0.39, and 0.77 µg/L for fC₆₀-bifenthrin mix; 6.63, 9.89, and 5.79 µg/L for tribufos; and 9.17, 8.17, and 6.59 µg/L for fC₆₀-tribufos mix. Mixtures did not affect instantaneous growth rate (p > 0.05). These results suggest that fC₆₀ had little effect on pesticide chronic toxicity but influenced acute toxicity. Given the widespread application of nanotechnology, the influence of nanomaterials on environmental contaminants is an important consideration. Thus, our results may be useful in the development and use of nanotechnology in agricultural practices. © 2010 SETAC.

  11. Impact of Microplastic Beads and Fibers on Waterflea (Ceriodaphnia dubia) Survival, Growth, and Reproduction: Implications of Single and Mixture Exposures.

    Science.gov (United States)

    Ziajahromi, Shima; Kumar, Anupama; Neale, Peta A; Leusch, Frederic D L

    2017-11-21

    There is limited knowledge regarding the adverse effects of wastewater-derived microplastics, particularly fibers, on aquatic biota. In this study, we examined the acute (48 h) and chronic (8 d) effects of microplastic polyester fibers and polyethylene (PE) beads on freshwater zooplankton Ceriodaphnia dubia. We also assessed the acute response of C. dubia to a binary mixture of microplastic beads and fibers for the first time. Acute exposure to fibers and PE beads both showed a dose-dependent effect on survival. An equitoxic binary mixture of beads and fibers resulted in a toxic unit of 1.85 indicating less than additive effects. Chronic exposure to lower concentrations did not significantly affect survival of C. dubia, but a dose-dependent effect on growth and reproduction was observed. Fibers showed greater adverse effects than PE beads. While ingestion of fibers was not observed, scanning electron microscopy showed carapace and antenna deformities after exposure to fibers, with no deformities observed after exposure to PE beads. While much of the current research has focused on microplastic beads, our study shows that microplastic fibers pose a greater risk to C. dubia, with reduced reproductive output observed at concentrations within an order of magnitude of reported environmental levels.

  12. Survival, growth and reproduction of the imported ampullarid snail Marisa cornuarietis in Central Sudan.

    Science.gov (United States)

    Haridi, A A; el Safi, S H; Jobin, W R

    1985-04-01

    The ampullarid snail Marisa cornuarietis was imported to the Sudan in 1981 for evaluation as a biological control agent against the planorbid snails which transmit human schistosomes. In initial field studies in small protected ponds the generation time of M. cornuarietis was 4 months, as in Puerto Rico. The snails reached 4 cm in diameter after 1 year, compared to 3 cm in Puerto Rico. Their population density varied from 60 to 175 snails per metre of shore-line, compared to a similar pond in Puerto Rico where the stable density was about 115 snails per metre. The proportion surviving after 1 year was 0.03, less than the annual proportion surviving of 0.10 in Puerto Rico. Thus the preliminary results indicated that the ampullarid snails could establish strong populations in permanent habitats in central Sudan where there was adequate food, although it might take longer than it does in Puerto Rico.

  13. Chronic effect of low pH on fathead minnow survival, growth, and reproduction

    Energy Technology Data Exchange (ETDEWEB)

    Mount, D I

    1973-01-01

    Fathead minnows (Pimephales promelas rafinesque) were continuously exposed to reduced pH levels of 4.5, 5.2, 5.9, 6.6, and 7.5 (control) during a 13-month, one-generation test. Survival was not affected, even at the lowest pH tested. Fish behavior was abnormal, and fish were deformed at pH 4.5 and 5.2. Egg production and egg hatchability were reduced at pH 5.9 and lower, and all eggs were abnormal. A pH of 6.6 was marginal for vital life functions, but safe for continuous exposure. Free carbon dioxide, liberated by the addition of sulfuric acid to reduce the pH, may have had an unknown effect. The fish did not become acclimiated to low pH levels.

  14. The effects of Copper and Zinc on survival, growth and reproduction of the cladoceran Daphnia longispina: introducing new data in an "old" issue.

    Science.gov (United States)

    Martins, Celso; Jesus, Fátima T; Nogueira, António J A

    2017-11-01

    Metal contamination is still a major environmental issue due to their continuous deposition and persistence. In this work we intended to assess the impact that Copper (Cu) and Zinc (Zn) exert in life-history parameters of Daphnia longispina, a common cladoceran in freshwater environments. Thus, we studied the effects of Cu (20-300 µg/L) and Zn (500-4000 µg/L) on the survival, growth, reproduction, feeding rate and population growth rate of D. longispina. Though survival was only reduced for the highest concentration of each metal, other endpoints were strongly affected by lower concentrations. Growth was affected by both metals, especially in the period 0-7 d, being significant for Cu ≥ 40 µg/L and Zn ≥ 500 µg/L. Indeed, growth endpoints at day 7 (body length and growth rate) were equally or more sensitive than the corresponding endpoints at day 21. The size at first reproduction decreased (significant for Cu ≥ 40 µg/L and Zn ≥ 500 µg/L). Reproduction decreased, which was partially explained by the reduced growth, but additional effects were supported by a direct effect of metals on reproduction (based on the relationship body length-brood size). Reduced growth and reproduction are likely a food mediated effect due to feeding inhibition caused by the metals. Globally, the studied endpoints were affected by Cu and Zn differently, supporting a chemical-specificity of the effects, with Zn causing more pronounced effects than Cu. This work presents an innovative approach to the effects of Cu and Zn to D. longispina, giving a general and comprehensive overview of those effects.

  15. Effects of reproduction on growth and survival in Atlantic cod, Gadus morhua, assessed by comparison to triploids

    DEFF Research Database (Denmark)

    Trippel, Edward A.; Butts, Ian; Babin, Amanda

    2014-01-01

    in captive iteroparous, batch-spawning Atlantic cod (Gadus morhua), utilizing diploids and triploids, knowing that triploid females invest little to no energy into gametogenesis. Based on annual specific growth rate, there was no evidence for a somatic cost of reproduction at ages 2 (virgin year) and 4...

  16. Survival, growth and reproduction of non-indigenous Nile tilapia, Oreochromis niloticus (Linnaeus 1758). I. Physiological capabilities in various temperatures and salinities

    Science.gov (United States)

    Schofield, Pamela J.; Peterson, Mark S.; Lowe, Michael R.; Brown-Peterson, Nancy J.; Slack, William T.

    2011-01-01

    The physiological tolerances of non-native fishes is an integral component of assessing potential invasive risk. Salinity and temperature are environmental variables that limit the spread of many non-native fishes. We hypothesised that combinations of temperature and salinity will interact to affect survival, growth, and reproduction of Nile tilapia, Oreochromis niloticus, introduced into Mississippi, USA. Tilapia withstood acute transfer from fresh water up to a salinity of 20 and survived gradual transfer up to 60 at typical summertime (30°C) temperatures. However, cold temperature (14°C) reduced survival of fish in saline waters ≥10 and increased the incidence of disease in freshwater controls. Although fish were able to equilibrate to saline waters in warm temperatures, reproductive parameters were reduced at salinities ≥30. These integrated responses suggest that Nile tilapia can invade coastal areas beyond their point of introduction. However, successful invasion is subject to two caveats: (1) wintertime survival depends on finding thermal refugia, and (2) reproduction is hampered in regions where salinities are ≥30. These data are vital to predicting the invasion of non-native fishes into coastal watersheds. This is particularly important given the predicted changes in coastal landscapes due to global climate change and sea-level rise.

  17. Life-history strategies of North American elk: trade-offs associated with reproduction and survival

    Science.gov (United States)

    Sabrina Morano; Kelley M. Stewart; James S. Sedinger; Christopher A. Nicolai; Marty Vavra

    2013-01-01

    The principle of energy allocation states that individuals should attempt to maximize fitness by allocating resources optimally among growth, maintenance, and reproduction. Such allocation may result in trade-offs between survival and reproduction, or between current and future reproduction. We used a marked population of North American elk (Cervus elaphus...

  18. Survival and reproduction of radio-marked adult spotted owls.

    Science.gov (United States)

    C.C. Foster; E.D. Forsman; E.C. Meslow; G.S. Miller; J.A. Reid; F.F. Wagner; A.B. Carey; J.B. Lint

    1992-01-01

    We compared survival, reproduction, and body mass of radio-marked and non radio-marked spotted owls (Strix occidentalis) to determine if backpack radios influenced reproduction or survival. In most study areas and years, there were no differences (P > 0.05) in survival of males and females or in survival of radio-marked versus banded owls. There...

  19. The influence of caffeine and thymol on the survival, growth and reproduction of Subulina octona (Brugüière, 1789 (Mollusca, Subulinidae

    Directory of Open Access Journals (Sweden)

    Paula Ferreira

    2009-08-01

    Full Text Available Subulina octona is a terrestrial snail which serves as an intermediate host for the parasites. It is also an agricultural pest. The aim of this work was to assess, during 120 days, the effects of caffeine and thymol at 2.5 g/L and 5 g/L on the hatchability, survival after hatching, growth and reproduction of S. octona under the laboratory conditions. A total of 240 eggs, 240 juveniles aged 10-day-old, and 240 aged 30-day-old were tested. The results showed that thymol (at 2.5 g/L and 5 g/L and caffeine (at 5 g/L acted as ovicides. In the 10-day-old juveniles, caffeine at 5 g/L caused 25% mortality and at 2.5 g/L it caused 30% mortality. Thymol at 2.5 and 5 g/L caused 20 and 22.5% mortality, respectively. In the 30-day-old juveniles, caffeine at 5 g/L caused 47.5% mortality.Subulina octona é um molusco terrestre que atua como hospedeiro intermediário de parasitos. Também atua como praga agrícola. O objetivo deste trabalho foi avaliar, durante 120 dias, o efeito da cafeína e do timol a 2,5g/L e a 5g/L, sobre a eclodibilidade, a sobrevivência após a eclosão, crescimento e a reprodução de S. octona em condições de laboratório. Foram testados 240 ovos, 240 jovens com 10 e 30 dias de vida. Os resultados dos testes mostraram que o timol (5g/L e 2,5g/L e a cafeína a 5g/L atuaram como ovicida. Nos jovens com 10 dias de vida a cafeína à 5g/L provocou uma mortalidade de 25% e a 2,5 g/L 30%. O timol a 2,5g/L e 5g/L provocou 20 e 22,5% de mortalidade, respectivamente. Nos jovens com 30 dias de vida a cafeína a 5g/L causou 47,5% de mortalidade. Esses resultados sugerem novos estudos no campo.

  20. Growth, Survival and Reproduction of the Giant Clam Tridacna maxima (Röding 1798, Bivalvia) in Two Contrasting Lagoons in French Polynesia

    Science.gov (United States)

    Van Wynsberge, Simon; Andréfouët, Serge; Gaertner-Mazouni, Nabila; Wabnitz, Colette C. C.; Menoud, Mathilde; Le Moullac, Gilles; Levy, Peva; Gilbert, Antoine; Remoissenet, Georges

    2017-01-01

    Shell growth, reproduction, and natural mortality of the giant clam Tridacna maxima were characterized over a two-year-period in the lagoon of the high island of Tubuai (Austral Archipelago) and in the semi-closed lagoon of Tatakoto (Tuamotu Archipelago) in French Polynesia. We also recorded temperature, water level, tidal slope, tidal range, and mean wave height in both lagoons. Lower lagoon aperture and exposure to oceanic swells at Tatakoto than at Tubuai was responsible for lower lagoon water renewal, as well as higher variability in temperature and water level at Tatakoto across the studied period. These different environmental conditions had an impact on giant clams. Firstly, spawning events in the lagoon of Tatakoto, detected by gonad maturity indices in June and July 2014, were timed with high oceanic water inflow and a decrease in lagoon water temperature. Secondly, temperature explained differences in shell growth rates between seasons and lagoons, generating different growth curves for the two sites. Thirdly, local mortality rates were also found to likely be related to water renewal patterns. In conclusion, our study suggests that reef aperture and lagoon water renewal rates play an integral role in giant clam life history, with significant differences in rates of shell growth, mortality and fertility found between open versus semi-closed atoll lagoons in coral reef ecosystems. PMID:28118406

  1. Growth, Survival and Reproduction of the Giant Clam Tridacna maxima (Röding 1798, Bivalvia in Two Contrasting Lagoons in French Polynesia.

    Directory of Open Access Journals (Sweden)

    Simon Van Wynsberge

    Full Text Available Shell growth, reproduction, and natural mortality of the giant clam Tridacna maxima were characterized over a two-year-period in the lagoon of the high island of Tubuai (Austral Archipelago and in the semi-closed lagoon of Tatakoto (Tuamotu Archipelago in French Polynesia. We also recorded temperature, water level, tidal slope, tidal range, and mean wave height in both lagoons. Lower lagoon aperture and exposure to oceanic swells at Tatakoto than at Tubuai was responsible for lower lagoon water renewal, as well as higher variability in temperature and water level at Tatakoto across the studied period. These different environmental conditions had an impact on giant clams. Firstly, spawning events in the lagoon of Tatakoto, detected by gonad maturity indices in June and July 2014, were timed with high oceanic water inflow and a decrease in lagoon water temperature. Secondly, temperature explained differences in shell growth rates between seasons and lagoons, generating different growth curves for the two sites. Thirdly, local mortality rates were also found to likely be related to water renewal patterns. In conclusion, our study suggests that reef aperture and lagoon water renewal rates play an integral role in giant clam life history, with significant differences in rates of shell growth, mortality and fertility found between open versus semi-closed atoll lagoons in coral reef ecosystems.

  2. Growth and reproductive attributes of radionuclide phytoremediators ...

    African Journals Online (AJOL)

    The study reveals that growth attributes including relative growth rate, net assimilation rate, leaf are index and specific leaf area, dry matter allocated to stem and leaves and number of reproductive organs decreased with the increase of radionuclide content of the plant, while the dry matter allocated to root and reproductive ...

  3. Selected endocrine disrupting compounds (vinclozolin, flutamide, ketoconazole and dicofol): effects on survival, occurrence of males, growth, molting and reproduction of Daphnia magna.

    Science.gov (United States)

    Haeba, Maher H; Hilscherová, Klára; Mazurová, Edita; Bláha, Ludek

    2008-05-01

    Pollution-induced endocrine disruption in vertebrates and invertebrates is a worldwide environmental problem, but relatively little is known about effects of endocrine disrupting compounds (EDCs) in planktonic crustaceans (including Daphnia magna). Aims of the present study were to investigate acute 48 h toxicity and sub-chronic (4-6 days) and chronic (21 days) effects of selected EDCs in D. magna. We have investigated both traditional endpoints as well as other parameters such as sex determination, maturation, molting or embryogenesis in order to evaluate the sensitivity and possible use of these endpoints in ecological risk assessment. We have studied effects of four model EDCs (vinclozolin, flutamide, ketoconazole and dicofol) on D. magna using (i) an acute 48 h immobilization assay, (ii) a sub-chronic, 4-6 day assay evaluating development and the sex ratio of neonates, and (iii) a chronic, 21 day assay studying number of neonates, sex of neonates, molting frequency, day of maturation and the growth of maternal organisms. Acute EC50 values in the 48 h immobilization test were as follows (mg/L): dicofol 0.2, ketoconazole 1.5, flutamide 2.7, vinclozolin >3. Short-term, 4-6 day assays with sublethal concentrations showed that the sex ratio in Daphnia was modulated by vinclozolin (decreased number of neonate males at 1 mg/L) and dicofol (increase in males at 0.1 mg/L). Flutamide (up to 1 mg/L) had no effect on the sex of neonates, but inhibited embryonic development at certain stages during chronic assay, resulting in abortions. Ketoconazole had no significant effects on the studied processes up to 1 mg/L. Sex ratio modulations by some chemicals (vinclozolin and dicofol) corresponded to the known action of these compounds in vertebrates (i.e. anti-androgenicity and anti-oestrogenicity, respectively). Our study revealed that some chemicals known to affect steroid-regulated processes in vertebrates can also affect sublethal endpoints (e.g. embryonic sex determination

  4. Review article: Vegetative growth, reproduction, browse production ...

    African Journals Online (AJOL)

    Vegetative growth, reproduction, browse production and response to tree clearing of ... water stress, soil nutrient availability, carbohydrate reserves, plant hormones, ... animal-plant interactions) of woody plants in various savanna ecosystems.

  5. Poor horse traders: large mammals trade survival for reproduction during the process of feralization

    Science.gov (United States)

    Grange, Sophie; Duncan, Patrick; Gaillard, Jean-Michel

    2009-01-01

    We investigated density dependence on the demographic parameters of a population of Camargue horses (Equus caballus), individually monitored and unmanaged for eight years. We also analysed the contributions of individual demographic parameters to changes in the population growth rates. The decrease in resources caused a loss of body condition. Adult male survival was not affected, but the survival of foals and adult females decreased with increasing density. Prime-aged females maintained high reproductive performance at high density, and their survival decreased. The higher survival of adult males compared with females at high density presumably results from higher investment in reproduction by mares. The high fecundity in prime-aged females, even when at high density, may result from artificial selection for high reproductive performance, which is known to have occurred in all the major domestic ungulates. Other studies suggest that feral ungulates including cattle and sheep, as these horses, respond differently from wild ungulates to increases in density, by trading adult survival for reproduction. As a consequence, populations of feral animals should oscillate more strongly than their wild counterparts, since they should be both more invasive (as they breed faster), and more sensitive to harsh environmental conditions (as the population growth rate of long-lived species is consistently more sensitive to a given proportional change in adult survival than to the same change in any other vital rate). If this principle proves to be general, it has important implications for management of populations of feral ungulates. PMID:19324787

  6. Relative effects of survival and reproduction on the population dynamics of emperor geese

    Science.gov (United States)

    Schmutz, Joel A.; Rockwell, Robert F.; Petersen, Margaret R.

    1997-01-01

    Populations of emperor geese (Chen canagica) in Alaska declined sometime between the mid-1960s and the mid-1980s and have increased little since. To promote recovery of this species to former levels, managers need to know how much their perturbations of survival and/or reproduction would affect population growth rate (λ). We constructed an individual-based population model to evaluate the relative effect of altering mean values of various survival and reproductive parameters on λ and fall age structure (AS, defined as the proportion of juv), assuming additive rather than compensatory relations among parameters. Altering survival of adults had markedly greater relative effects on λ than did equally proportionate changes in either juvenile survival or reproductive parameters. We found the opposite pattern for relative effects on AS. Due to concerns about bias in the initial parameter estimates used in our model, we used 5 additional sets of parameter estimates with this model structure. We found that estimates of survival based on aerial survey data gathered each fall resulted in models that corresponded more closely to independent estimates of λ than did models that used mark-recapture estimates of survival. This disparity suggests that mark-recapture estimates of survival are biased low. To further explore how parameter estimates affected estimates of λ, we used values of survival and reproduction found in other goose species, and we examined the effect of an hypothesized correlation between an individual's clutch size and the subsequent survival of her young. The rank order of parameters in their relative effects on λ was consistent for all 6 parameter sets we examined. The observed variation in relative effects on λ among the 6 parameter sets is indicative of how relative effects on λ may vary among goose populations. With this knowledge of the relative effects of survival and reproductive parameters on λ, managers can make more informed decisions about

  7. Parthenogenetic reproduction of Diaphanosoma celebensis (Crustacea: Cladocera). Effect of algae and algal density on survival, growth, life span and neonate production

    Digital Repository Service at National Institute of Oceanography (India)

    Shrivastava, Y.; Mahambre, G.G.; Achuthankutty, C.T.; Fernandes, Brenda; Goswami, S.C.; Madhupratap, M.

    ) and Tetraselmis gracilis (Kylin), was determined. Growth was faster in the initial stage with all three diets but slowed down in later life. Increased food concentrations resulted in higher neonate production but reduced the life span of females. However, long...

  8. Growth response and survival of Heterobranchus longifilis ...

    African Journals Online (AJOL)

    GRACE

    2006-05-02

    May 2, 2006 ... Different species of fish have been shown to have different optimum .... comparative study on the morphology, growth rate and reproduction of Clarias ... with artificial diets in aquaria, Aquaculture 37: 39-50. Ugwumba AAA ...

  9. Interannual variability of growth and reproduction in Bursera simaruba: the role of allometry and resource variability.

    Science.gov (United States)

    Hulshof, Catherine M; Stegen, James C; Swenson, Nathan G; Enquist, Carolyn A F; Enquist, Brian J

    2012-01-01

    Plants are expected to differentially allocate resources to reproduction, growth, and survival in order to maximize overall fitness. Life history theory predicts that the allocation of resources to reproduction should occur at the expense of vegetative growth. Although it is known that both organism size and resource availability can influence life history traits, few studies have addressed how size dependencies of growth and reproduction and variation in resource supply jointly affect the coupling between growth and reproduction. In order to understand the relationship between growth and reproduction in the context of resource variability, we utilize a long-term observational data set consisting of 670 individual trees over a 10-year period within a local population of Bursera simaruba (L.) Sarg. We (1) quantify the functional form and variability in the growth-reproduction relationship at the population and individual-tree level and (2) develop a theoretical framework to understand the allometric dependence of growth and reproduction. Our findings suggest that the differential responses of allometric growth and reproduction to resource availability, both between years and between microsites, underlie the apparent relationship between growth and reproduction. Finally, we offer an alternative approach for quantifying the relationship between growth and reproduction that accounts for variation in allometries.

  10. Foreign acquisition, plant survival, and employment growth

    DEFF Research Database (Denmark)

    Bandick, Roger; Görg, Holger

    2010-01-01

    This paper analyzes the effect of foreign acquisition on survival and employment growth of targets using data on Swedish manufacturing plants.We separate targeted plants into those within Swedish MNEs, Swedish exporting non-MNEs, and purely domestic firms. The results, controlling for possible...... acquisitions. We find robust positive employment growth effects only for exporters and only if the takeover is vertical....

  11. Growth response and survival of Heterobranchus longifilis ...

    African Journals Online (AJOL)

    In an effort to utilize feed efficiently, promote growth, increase survival and reduce labour costs associated with feeding, Heterobranchus longifilis ingerlings were placed on one of four feeding frequencies; once/day, twice/day; once every other day, and twice every other day for 56 days. They were fed with a commercial ...

  12. Seasonal timing in a warming world : Plasticity of seasonal timing of growth and reproduction

    NARCIS (Netherlands)

    Salis, Lucia

    2015-01-01

    In seasonal environments the timing of various biological processes is crucial for growth, survival and reproductive success of an individual. Nowadays, rapid large-scale climate change is altering species’ seasonal timing (phenology) in many eco¬systems. In this thesis Lucia Salis focuses on the

  13. Evaluation of growth and reproduction as indicators of soil metal toxicity to the Collembolan, Sinella curviseta

    DEFF Research Database (Denmark)

    Xu, Jie; Ke, Xin; Krogh, Paul Henning

    2009-01-01

    Laboratory studies evaluated the sensitivity of Sinella curviseta Brook (Collembola: Entomobryidae) to selected heavy metals (Cu, Pb and Zn). Survival, reproduction and growth of S. curviseta were determined in a 4-week exposure test in an agricultural soil amended with metals to concentrations...

  14. Reproductive factors and epithelial ovarian cancer survival in the EPIC cohort study

    NARCIS (Netherlands)

    Be͉ević, Jelena; Gunter, Marc J.; Fortner, Renee T.; Tsilidis, Konstantinos K.; Weiderpass, Elisabete; Onland-Moret, N. Charlotte; Dossus, Laure; TjØnneland, Anne; Hansen, Louise; Overvad, Kim; Mesrine, Sylvie; Baglietto, Laura; Clavel-Chapelon, Francoise; Kaaks, Rudolf; Aleksandrova, Krasimira; Boeing, Heiner; Trichopoulou, Antonia; Lagiou, Pagona; Bamia, Christina; Masala, Giovanna; Agnoli, Claudia; Tumino, Rosario; Ricceri, Fulvio; Panico, Salvatore; Bueno-de-Mesquita, H. B.; Peeters, Petra H.; Jareid, Mie; Quirós, J. Ramon; Duell, Eric J.; Sánchez, Maria Jose; Larrañaga, Nerea; Chirlaque, Maria Dolores; Barricarte, Aurelio; Dias, Joana A.; Sonestedt, Emily; Idahl, Annika; Lundin, Eva; Wareham, Nicholas J.; Khaw, Kay Tee; Travis, Ruth C.; Rinaldi, Sabina; Romieu, Isabelle; Riboli, Elio; Merritt, Melissa A.

    2015-01-01

    Background:Reproductive factors influence the risk of developing epithelial ovarian cancer (EOC), but little is known about their association with survival. We tested whether prediagnostic reproductive factors influenced EOC-specific survival among 1025 invasive EOC cases identified in the European

  15. Foreign acquisition, plant survival, and employment growth

    DEFF Research Database (Denmark)

    Bandick, Roger; Görg, Holger

    This paper analyses the effect of foreign acquisition on survival probability and employment growth of target plant using data on Swedish manufacturing plants during the period 1993-2002.  An improvement over previous studies is that we take into account firm level heterogeneity by separating...... the lifetime of the acquired plants only if the plant was an exporter.  The effect differs depending on whether the acquisition is horizontal or vertical.  We also find robust positive employment growth effects only for exporters, and only if the takeover is vertical, not horizontal....

  16. Impacts of chemicals on waterfowl reproduction and survival

    Science.gov (United States)

    White, D.H.; Stickel, L.F.

    1975-01-01

    Residues of organochlorine pesticides, PCB's, heavy metals, and other toxic chemicals are ubiquitous in the biosphere and are commonly found in tissues and eggs of wild birds. This paper reviews research on the effects of these chemicals, with particular reference to waterfowl. Extensive mortality of waterfowl has occurred in the Gulf Coast region as a result of ingestion of aldrin-treated rice seed. Populations of fulvous tree ducks (Dendrocygna bicolor) have declined in recent years in that area. DDE impaired reproduction of both mallards (Anas platyrhynchos) and black ducks (Arias rubripes) in experimental studies, resulting in thin shells, cracked eggs, and poor hatching success. Eggs incubated by the hens broke and cracked more frequently than those in incubators. In the field, residues are higher in ducks that feed on animal material than in vegetarians; differences are pronounced both geographically and among species. Mercury at levels that occur in certain heavily polluted areas in the United States and Canada has, in experimental studies, lowered the reproductive success of mallards and black ducks and reduced the survival of ducklings. Oil spills have killed many waterfowl as a result of oiled feathers and the intake of oil and more indirect physiological effects have been shown experimentally. Pollutants may affect waterfowl indirectly by changing the habitat and directly as a result of intake of toxic substances. They are unlikely to have been directly limiting factors in populations of such species as mallards. Their involvement with problem of other species, including canvasbacks (Aythya valisineria) and mergansers has still to be explored.

  17. Growth and Reproduction of Artificially Fed Cnaphalocrocis medinalis

    Directory of Open Access Journals (Sweden)

    Jian XU

    2012-09-01

    Full Text Available The growth and reproduction of rice leaffolder, Cnaphalocrocis medinalis, fed on an artificial diet were studied. The results showed that the larvae were able to grow and pupate on the artificial diet. The durations of larvae and pupas of C. medinalis on the artificial diet were 28.1 d and 10.1 d, postponed 4.9 d and 1.7 d respectively, compared with those reared with rice leaves. The number of ovipositions was 41.6 per female, 26.2% higher than that fed on rice leaves. Survival rate curve of larvae was a descent function of mortality-age, with no significant differences from the curve of larvae fed on rice leaves. The net reproductive rate (Ro, intrinsic rate of increase (rm and finite rate of increase (λ of the population fed on diet were 17.6928, 0.0884 and 1.0924, respectively, and the mean generation time (T and double time (td were prolonged 4.9 d and 1.3 d in comparison with the treatment of rice leaves. Population trend index (I was 3.26, indicating a growing number of the population of C. medinalis fed on artificial diet.

  18. The effects of food availability on growth and reproduction of Daphnia magna exposed to silver nanoparticles

    DEFF Research Database (Denmark)

    Mackevica, Aiga; Skjolding, Lars Michael; Gergs, A.

    ) were performed using 30 nm citric acid stabilized AgNP. The aim of the study was, besides providing data for the chronic toxicity of AgNP, to study the influence of the food availability on the reproductive toxicity of AgNP in Daphnia magna. The exposure concentrations applied ranged from 2 to 50 μg...... to controls, whereas concentrations above 10 μgAg/L resulted in inhibition of growth and reproduction as well as an increased mortality. The addition of higher amounts of food showed a beneficial effect on animal survival, growth and reproduction. Similar as in normal food availability treatment, animals......The number of available studies on the acute effects of silver nanoparticles (AgNP) on aquatic organisms has increased dramatically in recent years, but there is still very limited information available on chronic effects. In this study, a series of Daphnia magna 21-days reproduction test (OECD 211...

  19. Dominance, reproduction and survival in banded mongooses: towards an egalitarian social system?

    Science.gov (United States)

    de Luca, D. W.; Ginsberg, J. R.

    2001-01-01

    The banded mongoose, Mungos mungo, is a social species that forms multimale and multifemale family groups. Earlier studies suggest these family groups are relatively egalitarian with small differences in reproductive opportunities among individuals of different rank. In contrast, previous studies of other social mongooses have focused on species with more despotic control of reproduction (meerkats, Suricata suricatta, dwarf mongooses, Helogale parvula). In these species, the distribution of reproductive opportunities amongst individuals of different rank has met the predictions of reproductive skew theory: dominant individuals accrue greater reproductive benefits than subordinates, with subordinates breeding less often than dominants. In this paper we test how well two predictions of reproductive skew theory explain variance in measures of reproductive effort, and its correlates, in a wild population of banded mongooses in Queen Elizabeth National Park, Uganda. We measure dominance rank in males and females, and we investigate whether individuals of higher social rank accrue greater benefits than subordinates in terms of survival and reproduction. Banded mongoose dominance hierarchies showed linearity, but low reproductive skew. Rank was not significantly correlated with age. Furthermore, there were only small effects of dominance rank on nutritional levels, and no effects on reproduction and survival, suggesting that banded mongoose societies are indeed relatively egalitarian. No evidence of reproductive suppression was found and other forms of reproductive control were not observed. However, we do not exclude the possibility of increased reproductive competition in circumstances of higher ecological constraints. These findings show that reproductive skew theory is equally useful in explaining variation in reproduction in societies with low reproductive skew, as it is in explaining the allocation of reproductive effort in despotic social systems. Copyright 2001

  20. The effects of uranium on reproduction, gestation, and postnatal survival in mice

    International Nuclear Information System (INIS)

    Paternain, J.L.; Domingo, J.L.; Ortega, A.; Llobet, J.M.

    1989-01-01

    Uranyl acetate dihydrate was tested for its effects on reproduction, gestation, and postnatal survival in Swiss mice. Four groups of animals, each of which consisted of 25 males and 25 females, were administered 0, 5, 10, and 25 mg/kg/day of uranyl acetate dihydrate. Mature male mice were treated orally for 60 days prior to mating with mature virgin female mice treated orally for 14 days prior to mating. Treatment of the females continued throughout mating, gestation, parturition, and nursing of the litters. One-half of the dams in each group were sacrificed on Day 13 of gestation and the remaining dams were allowed to deliver and wean their offspring. Postnatal development was monitored after 0, 4, and 21 days of lactation. No adverse effects on fertility were evident at the doses employed in this study. Nevertheless, embryolethality could be observed in the 25 mg/kg/day group. Significant increases in the number of dead young per litter were seen at birth and at Day 4 of lactation in the 25 mg/kg/day group. The growth of the offspring was always significantly lower for the uranium-treated animals. However, the present results suggest that uranium does not cause any adverse effects on fertility, general reproductive parameters, or offspring survival at the concentrations usually ingested by man

  1. Effect of uranium on growth and reproduction of the marine amphipod Allorchestes compressa

    International Nuclear Information System (INIS)

    Ahsanullah, M.; Williams, A.R.

    1986-01-01

    Experiments on growth of the marine amphipod Allorchestes compressa Dana were carried out over four weeks, and both growth and reproduction were studied over three generations, each of which was exposed to uranium for approximately 10 wk. At 0.1 mg l -1 the uranium increased growth by 23%, as measured by the mean weight after 4 wk, and at 2 mg l -1 growth was reduced by 28% compared with the control. A. compressa accumulated uranium from sea water with a concentration factor of 10. There was no effect of uranium on the survival of amphipods or their progeny in the multiple-generation experiment, but the numbers of males, the sex ratio, and the respiration rate (measured on males only) at 1 mg l -1 were significantly lower than the control. A. compressa is shown to be a convenient species for the study of toxic effects on growth and reproduction using multiple-generation experiments. (orig.)

  2. Rainfall during parental care reduces reproductive and survival components of fitness in a passerine bird

    OpenAIRE

    ?berg, Meit; Arlt, Debora; P?rt, Tomas; Laugen, Ane T; Eggers, S?nke; Low, Matthew

    2014-01-01

    Adverse weather conditions during parental care may have direct consequences for offspring production, but longer-term effects on juvenile and parental survival are less well known. We used long-term data on reproductive output, recruitment, and parental survival in northern wheatears (Oenanthe oenanthe) to investigate the effects of rainfall during parental care on fledging success, recruitment success (juvenile survival), and parental survival, and how these effects related to nestling age,...

  3. The forms and fitness cost of senescence : Age-specific recapture, survival, reproduction, and reproductive value in a wild bird population

    NARCIS (Netherlands)

    Bouwhuis, Sandra; Choquet, Remi; Sheldon, Ben C.; Verhulst, Simon

    Longitudinal studies of senescence accumulate rapidly from natural populations. However, it is largely unknown whether different fitness components senesce in parallel, how reproductive and survival senescence contribute to declines in reproductive value, and how large the fitness cost of senescence

  4. Body Condition Indices Predict Reproductive Success but Not Survival in a Sedentary, Tropical Bird

    OpenAIRE

    Milenkaya, Olga; Catlin, Daniel H.; Legge, Sarah; Walters, Jeffrey R.

    2015-01-01

    Body condition may predict individual fitness because those in better condition have more resources to allocate towards improving their fitness. However, the hypothesis that condition indices are meaningful proxies for fitness has been questioned. Here, we ask if intraspecific variation in condition indices predicts annual reproductive success and survival. We monitored a population of Neochmia phaeton (crimson finch), a sedentary, tropical passerine, for reproductive success and survival ove...

  5. Nearby grandmother enhances calf survival and reproduction in Asian elephants.

    Science.gov (United States)

    Lahdenperä, Mirkka; Mar, Khyne U; Lummaa, Virpi

    2016-06-10

    Usually animals reproduce into old age, but a few species such as humans and killer whales can live decades after their last reproduction. The grandmother hypothesis proposes that such life-history evolved through older females switching to invest in their existing (grand)offspring, thereby increasing their inclusive fitness and selection for post-reproductive lifespan. However, positive grandmother effects are also found in non-menopausal taxa, but evidence of their associated fitness effects is rare and only a few tests of the hypothesis in such species exist. Here we investigate the grandmother effects in Asian elephants. Using a multigenerational demographic dataset on semi-captive elephants in Myanmar, we found that grandcalves from young mothers (years) had 8 times lower mortality risk if the grandmother resided with her grandcalf compared to grandmothers residing elsewhere. Resident grandmothers also decreased their daughters' inter-birth intervals by one year. In contrast to the hypothesis predictions, the grandmother's own reproductive status did not modify such grandmother benefits. That elephant grandmothers increased their inclusive fitness by enhancing their daughter's reproductive rate and success irrespective of their own reproductive status suggests that fitness-enhancing grandmaternal effects are widespread, and challenge the view that grandmother effects alone select for menopause coupled with long post-reproductive lifespan.

  6. Age-specific growth, reproductive values, and intrinsic r

    Directory of Open Access Journals (Sweden)

    Robert Schoen

    2011-06-01

    Full Text Available The age-specific growth function of an observed population and the reproductive value function based on the population's current vital rates determine the intrinsic rate of growth implied by those vital rates through the simple relationship given in equation (1. That equation establishes the analytical significance of age-specific growth, and leads to relationships that quantify a population's approach to stability and that specify the extraordinarily close connection between reproductive values and population momentum.

  7. Age, growth and reproductive biology of the blue shark Prionace ...

    African Journals Online (AJOL)

    The age, growth and reproductive biology of the blue shark Prionace glauca from South African waters were assessed using 205 specimens, ranging in total length (TL) from 72 to 313 cm. Greater number of males (120) than females (85) were examined as they were more frequently caught. Age and growth parameters ...

  8. Population density shapes patterns of survival and reproduction in Eleutheria dichotoma (Hydrozoa: Anthoathecata).

    Science.gov (United States)

    Dańko, Aleksandra; Schaible, Ralf; Pijanowska, Joanna; Dańko, Maciej J

    2018-01-01

    Budding hydromedusae have high reproductive rates due to asexual reproduction and can occur in high population densities along the coasts, specifically in tidal pools. In laboratory experiments, we investigated the effects of population density on the survival and reproductive strategies of a single clone of Eleutheria dichotoma . We found that sexual reproduction occurs with the highest rate at medium population densities. Increased sexual reproduction was associated with lower budding (asexual reproduction) and survival probability. Sexual reproduction results in the production of motile larvae that can, in contrast to medusae, seek to escape unfavorable conditions by actively looking for better environments. The successful settlement of a larva results in starting the polyp stage, which is probably more resistant to environmental conditions. This is the first study that has examined the life-history strategies of the budding hydromedusa E. dichotoma by conducting a long-term experiment with a relatively large sample size that allowed for the examination of age-specific mortality and reproductive rates. We found that most sexual and asexual reproduction occurred at the beginning of life following a very rapid process of maturation. The parametric models fitted to the mortality data showed that population density was associated with an increase in the rate of aging, an increase in the level of late-life mortality plateau, and a decrease in the hidden heterogeneity in individual mortality rates. The effects of population density on life-history traits are discussed in the context of resource allocation and the r/K-strategies' continuum concept.

  9. Induced spawning, survival and growth of an African catfish hybrid ...

    African Journals Online (AJOL)

    Induced spawning, survival and growth of an African catfish hybrid (female Clarias gariepinus and male Clarias anguillaris ) fingerlings relative to their parental species in the mount Cameroon region.

  10. Growth and reproductive attributes of radionuclide phytoremediators ...

    African Journals Online (AJOL)

    use

    2011-11-23

    Nov 23, 2011 ... radio-phytoremediation of soils contaminated with uranium and thorium. Key words: Uranium ... Although, contaminated soils drastically affect the growth of plants and soil-living ...... Toxicity of cadmium, cobalt, uranium and.

  11. Local variability in growth and reproduction of Salix arctica in the High Arctic

    Directory of Open Access Journals (Sweden)

    Noémie Boulanger-Lapointe

    2016-06-01

    Full Text Available Arctic terrestrial ecosystems are heterogeneous because of the strong influences of microtopography, soil moisture and snow accumulation on vegetation distribution. The interaction between local biotic and abiotic factors and global climate patterns will influence species responses to climate change. Salix arctica (Arctic willow is a structuring species, ubiquitous and widespread, and as such is one of the most important shrub species in the High Arctic. In this study, we measured S. arctica reproductive effort, early establishment, survival and growth in the Zackenberg valley, north-east Greenland. We sampled four plant communities that varied with respect to snow conditions, soil moisture, nutrient content and plant composition. We found large variability in reproductive effort and success with total catkin density ranging from 0.6 to 66 catkins/m2 and seedling density from <1 to 101 seedlings/m2. There were also major differences in crown area increment (4–23 cm2/year and stem radial growth (40–74 µm/year. The snowbed community, which experienced a recent reduction in snow cover, supported young populations with high reproductive effort, establishment and growth. Soil nutrient content and herbivore activity apparently did not strongly constrain plant reproduction and growth, but competition by Cassiope tetragona and low soil moisture may inhibit performance. Our results show that local environmental factors, such as snow accumulation, have a significant impact on tundra plant response to climate change and will affect the understanding of regional vegetation response to climate change.

  12. Changes in growth, survival and digestive enzyme activities of Asian ...

    African Journals Online (AJOL)

    A study was conducted to determine the effects of different dietary treatments on the growth, survival and digestive enzyme activities of Mystus nemurus larvae. Newly hatched larvae were reared for 14 days in twelve 15 L glass aquaria (for growth and survival) and eight 300 L fiberglass tanks (for enzyme samples) at a ...

  13. Growth and reproductive investment of introduced Pacific oysters

    NARCIS (Netherlands)

    Cardoso, J.F.M.F.; Peralta, N.R.E.; Machado, J.P.; van der Veer, H.W.

    2013-01-01

    Growth and reproductive investment of cultured Pacific oysters Crassostrea gigas were studied in two south-western European estuaries: the Ria de Ribadeo in Spain and the Ria Formosa in Portugal. Developing gonads were found in individuals >23.5 mm shell length in the Ria Formosa and >27.5 mm shell

  14. Comparative reproductive biology of sympatric species: Nest and chick survival of American avocets and black-necked stilts

    Science.gov (United States)

    Ackerman, Joshua T.; Herzog, Mark P.; Takekawa, John Y.; Hartman, Christopher A.

    2014-01-01

    Identifying differences in reproductive success rates of closely related and sympatrically breeding species can be useful for understanding limitations to population growth. We simultaneously examined the reproductive ecology of American avocets Recurvirostra americana and black-necked stilts Himantopus mexicanus using 1274 monitored nests and 240 radio-marked chicks in San Francisco Bay, California. Although there were 1.8 times more avocet nests than stilt nests, stilts nonetheless fledged 3.3 times more chicks. Greater production by stilts than avocets was the result of greater chick survival from hatching to fledging (avocet: 6%; stilt: 40%), and not because of differences in clutch size (avocet: 3.84; stilt: 3.77), nest survival (avocet: 44%; stilt: 35%), or egg hatching success (avocet: 90%; stilt: 92%). We reviewed the literature and confirmed that nest survival and hatching success are generally similar when avocets and stilts breed sympatrically. In addition to species, chick survival was strongly influenced by age, site, and year. In particular, daily survival rates increased rapidly with chick age, with 70% of mortalities occurring ≤ 1 week after hatch. California gulls Larus californicus caused 55% of avocet, but only 15% of stilt, chick deaths. Differential use of micro-habitats likely reduced stilt chick’s vulnerability to gull predation, particularly during the first week after hatch, because stilts nested in vegetation 2.7 times more often than avocets and vegetation height was 65% taller at stilt nests compared with avocet nests. Our results demonstrate that two co-occurring and closely related species with similar life history strategies can differ markedly in reproductive success, and simultaneous studies of such species can identify differences that limit productivity.

  15. Survival and reproductive rate of mites in relation to resistance of their barn swallow hosts.

    Science.gov (United States)

    Møller, A P

    2000-08-01

    Parasite resistance may act via a number of different mechanisms that regulate or control the survival and the reproductive rate of parasites. Observations and experiments were used to test for effects of host resistance on parasite survival and rate of reproduction. Natural levels of infestation of barn swallow Hirundo rustica nests by the tropical fowl mite Ornithonyssus bursa were positively related to brood size, inversely related to the length of the outermost tail feathers of male nest owners (a secondary sexual character) and affected by time of reproduction by the host. A mite inoculation experiment, in which 50 adult mites were introduced into nests during the laying period of the host, was used to test for differential survival and reproduction of mites as a function of host resistance. The relationship between survival and reproduction of parasites, male tail length and host resistance was investigated. There was a negative relationship between mite numbers per nest after fledging of nestlings and male tail length. This relationship was mainly caused by a reduction in the number of mites in the first and second nymph stage with increasing tail length of male hosts, implying a reduction in rate of reproduction of mites. The proportion of mites that had recently fed was inversely related to tail length of male hosts. The proportion of nymph stages was positively related to the proportion of mites that had recently had a blood meal. Parasite resistance of barn swallows to the tropical fowl mite thus appeared to act through increased mortality rate of adult and nymph stages of mites, and through reduced reproductive rates of mites on resistant hosts. This is the first study demonstating a direct relationship between fitness components of a parasite and the expression of a secondary sexual character of a host.

  16. Oosorption in response to poor food: complexity in the trade-off between reproduction and survival

    Science.gov (United States)

    Moore, Patricia J; Attisano, Alfredo

    2011-01-01

    Plasticity in reproductive physiology is one avenue by which environmental signals, such as poor quality food, can be coordinated with adaptive responses. Insects have the ability to resorb oocytes that are not oviposited. Oosorption is proposed to be an adaptive mechanism to optimize fitness in hostile environments, recouping resources that might otherwise be lost, and reinvesting them into future reproductive potential. We tested the hypothesis that oosorption is an evolved mechanism by which females can reallocate resources from current reproductive effort to survival and future reproduction, when conditions for reproduction are poor, by examining the reproductive physiology and life-history outcome under poor quality food in populations of the milkweed bug (Oncopeltus fasciatus) that have adapted to live on sunflower seed. Females fed a diet of pumpkin seeds, known to be a poor host food, had higher levels of ovarian apoptosis (oosorption), lower reproductive output, but no reduction in life span under poor nutrition, as predicted under the oosorption hypothesis. However, the schedule of reproduction was surprising given the “wait to reproduce” assumption of oosorption as early fecundity was unaffected. PMID:22393481

  17. Effects of temperature on development, survival and reproduction of insects: Experimental design, data analysis and modeling

    Science.gov (United States)

    Jacques Regniere; James Powell; Barbara Bentz; Vincent Nealis

    2012-01-01

    The developmental response of insects to temperature is important in understanding the ecology of insect life histories. Temperature-dependent phenology models permit examination of the impacts of temperature on the geographical distributions, population dynamics and management of insects. The measurement of insect developmental, survival and reproductive responses to...

  18. Survival and reproduction of small hive beetle (Coleoptera: Nitidulidae) on commercial pollen substitutes

    Science.gov (United States)

    An assay was developed to investigate the small hive beetle’s (Aethina tumida) potential for survival and reproduction when providing artificial food resources in managed European honey bees (Apis mellifera). Supplemental feeding is done to maintain the health of the hive, initiate comb building, ex...

  19. When do we eat? Ingestive behavior, survival, and reproductive success.

    Science.gov (United States)

    Schneider, Jill E; Wise, Justina D; Benton, Noah A; Brozek, Jeremy M; Keen-Rhinehart, Erin

    2013-09-01

    The neuroendocrinology of ingestive behavior is a topic central to human health, particularly in light of the prevalence of obesity, eating disorders, and diabetes. The study of food intake in laboratory rats and mice has yielded some useful hypotheses, but there are still many gaps in our knowledge. Ingestive behavior is more complex than the consummatory act of eating, and decisions about when and how much to eat usually take place in the context of potential mating partners, competitors, predators, and environmental fluctuations that are not present in the laboratory. We emphasize appetitive behaviors, actions that bring animals in contact with a goal object, precede consummatory behaviors, and provide a window into motivation. Appetitive ingestive behaviors are under the control of neural circuits and neuropeptide systems that control appetitive sex behaviors and differ from those that control consummatory ingestive behaviors. Decreases in the availability of oxidizable metabolic fuels enhance the stimulatory effects of peripheral hormones on appetitive ingestive behavior and the inhibitory effects on appetitive sex behavior, putting a new twist on the notion of leptin, insulin, and ghrelin "resistance." The ratio of hormone concentrations to the availability of oxidizable metabolic fuels may generate a critical signal that schedules conflicting behaviors, e.g., mate searching vs. foraging, food hoarding vs. courtship, and fat accumulation vs. parental care. In species representing every vertebrate taxa and even in some invertebrates, many putative "satiety" or "hunger" hormones function to schedule ingestive behavior in order to optimize reproductive success in environments where energy availability fluctuates. © 2013. Published by Elsevier Inc. All rights reserved.

  20. Survival, reproduction, and recruitment of woody plants after 14 years on a reforested landfill

    Science.gov (United States)

    Robinson, George R.; Handel, Steven N.; Schmalhofer, Victoria R.

    1992-03-01

    With the advent of modern sanitary landfill closure techniques, the opportunity exists for transforming municipal landfills into urban woodlands. While costs of fullscale reforestation are generally prohibitive, a modest planting of clusters of trees and shrubs could initiate or accelerate population expansions and natural plant succession from open field to diverse forest. However, among woody species that have been screened for use on landfills, these ecological potentials have not yet been investigated. We examined a 14-yr-old landfill plantation in New Jersey, USA, established to test tolerance of 19 species of trees and shrubs to landfill environments. We measured survivorship, reproduction, and recruitment within and around the experimental installation. Half of the original 190 plants were present, although survival and growth rates varied widely among species. An additional 752 trees and shrubs had colonized the plantation and its perimeter, as well as 2955 stems of vines. However, the great majority (>95%) of woody plants that had colonized were not progeny of the planted cohort, but instead belonged to 18 invading species, mostly native, bird-dispersed, and associated with intermediate stages of secondary plant succession. Based on this evidence, we recommend that several ecological criteria be applied to choices of woody species for the restoration of municipal landfills and similar degraded sites, in order to maximize rapid and economical establishment of diverse, productive woodlands.

  1. Environmental Influences on Growth and Reproduction of Invasive Commelina benghalensis

    Directory of Open Access Journals (Sweden)

    Mandeep K. Riar

    2016-01-01

    Full Text Available Commelina benghalensis (Benghal dayflower is a noxious weed that is invading agricultural systems in the southeastern United States. We investigated the influences of nutrition, light, and photoperiod on growth and reproductive output of C. benghalensis. In the first experimental series, plants were grown under high or low soil nutrition combined with either full light or simulated shade. Lowered nutrition strongly inhibited vegetative growth and aboveground spathe production. Similar but smaller effects were exerted by a 50% reduction in light, simulating conditions within a developing canopy. In the second series of experiments, C. benghalensis plants were exposed to different photoperiod conditions that produced short- and long-day plants growing in similar photosynthetic periods. A short-day photoperiod decreased time to flowering by several days and led to a 40 to 60% reduction in vegetative growth, but reproduction above and below ground was unchanged. Collectively, the results indicate that (1 fertility management in highly weathered soils may strongly constrain competitiveness of C. benghalensis; (2 shorter photoperiods will limit vegetative competitiveness later in the growing seasons of most crops; and (3 the high degree of reproductive plasticity and output possessed by C. benghalensis will likely cause continual persistence problems in agricultural fields.

  2. Cultivation of sponge larvae: settlement, survival, and growth of juveniles

    NARCIS (Netherlands)

    Caralt, de S.; Otjens, H.; Uriz, M.J.; Wijffels, R.H.

    2007-01-01

    The aim of this study was to culture sponge juveniles from larvae. Starting from larvae we expected to enhance the survival and growth, and to decrease the variation in these parameters during the sponge cultures. First, settlement success, morphological changes during metamorphosis, and survival of

  3. Growth Hormone Overexpression Disrupts Reproductive Status Through Actions on Leptin

    Directory of Open Access Journals (Sweden)

    Ji Chen

    2018-03-01

    Full Text Available Growth and reproduction are closely related. Growth hormone (GH-transgenic common carp exhibit accelerated growth and delayed reproductive development, which provides an amenable model to study hormone cross talk between the growth and reproductive axes. We analyzed the energy status and reproductive development in GH-transgenic common carp by using multi-tissue RNA sequencing, real-time-PCR, Western blotting, ELISA, immunofluorescence, and in vitro incubation. The expression of gys (glycogen synthase and igfbp1 (insulin-like growth factor binding protein as well as blood glucose concentrations are lower in GH-transgenic carp. Agrp1 (agouti-related protein 1 and sla (somatolactin a, which are related to appetite and lipid catabolism, are significantly higher in GH-transgenic carp. Low glucose content and increased appetite indicate disrupted metabolic and energy deprivation status in GH-transgenic carp. Meanwhile, the expression of genes, such as gnrhr2 (gonadotropin-releasing hormone receptor 2, gthα (gonadotropin hormone, alpha polypeptide, fshβ (follicle stimulating hormone, beta polypeptide, lhβ [luteinizing hormone, beta polypeptide] in the pituitary, cyp19a1a (aromatase A in the gonad, and cyp19a1b (aromatase B in the hypothalamus, are decreased in GH-transgenic carp. In contrast, pituitary gnih (gonadotropin inhibitory hormone, drd1 (dopamine receptor D1, drd3 (dopamine receptor D3, and drd4 (dopamine receptor D4 exhibit increased expression, which were associated with the retarded reproductive development. Leptin receptor mRNA was detected by fluorescence in situ hybridization in the pituitary including the pars intermedia and proximal pars distalis, suggesting a direct effect of leptin on LH. Recombinant carp Leptin protein was shown to stimulate pituitary gthα, fshβ, lhβ expression, and ovarian germinal vesicle breakdown in vitro. In addition to neuroendocrine factors, we suggest that reduced hepatic leptin signaling to the

  4. Seasonal timing in a warming world : plasticity of seasonal timing of growth and reproduction

    OpenAIRE

    Salis, L.

    2015-01-01

    In seasonal environments the timing of various biological processes is crucial for growth, survival and reproductive success of an individual. Nowadays, rapid large-scale climate change is altering species’ seasonal timing (phenology) in many eco¬systems. In this thesis Lucia Salis focuses on the study of seasonal timing in the food chain of the oak-winter moth-great tit. As temperature increased over the last decades, both phenologies of the host plant, the oak, and the herbivorous insect, t...

  5. Symbiotic regulation of plant growth, development and reproduction

    Science.gov (United States)

    Rodriguez, R.J.; Freeman, D. Carl; McArthur, E.D.; Kim, Y.-O.; Redman, R.S.

    2009-01-01

    The growth and development of rice (Oryzae sativa) seedlings was shown to be regulated epigenetically by a fungal endophyte. In contrast to un-inoculated (nonsymbiotic) plants, endophyte colonized (symbiotic) plants preferentially allocated resources into root growth until root hairs were well established. During that time symbiotic roots expanded at five times the rate observed in nonsymbiotic plants. Endophytes also influenced sexual reproduction of mature big sagebrush (Artemisia tridentata) plants. Two spatially distinct big sagebrush subspecies and their hybrids were symbiotic with unique fungal endophytes, despite being separated by only 380 m distance and 60 m elevation. A double reciprocal transplant experiment of parental and hybrid plants, and soils across the hybrid zone showed that fungal endophytes interact with the soils and different plant genotypes to confer enhanced plant reproduction in soil native to the endophyte and reduced reproduction in soil alien to the endophyte. Moreover, the most prevalent endophyte of the hybrid zone reduced the fitness of both parental subspecies. Because these endophytes are passed to the next generation of plants on seed coats, this interaction provides a selective advantage, habitat specificity, and the means of restricting gene flow, thereby making the hybrid zone stable, narrow and potentially leading to speciation. ?? 2009 Landes Bioscience.

  6. Effects of food availability on growth and reproduction of the deep-sea pedunculate barnacle Heteralepas canci

    Science.gov (United States)

    Yasuda, Natsumi; Miyamoto, Norio; Fujiwara, Yoshihiro; Yamamoto, Tomoko; Yusa, Yoichi

    2016-02-01

    Sessile animals living on continental shelves or slopes may adjust their growth and reproduction according to temporally and spatially variable food availability, but little information is available on these animals to date. We collected the pedunculate barnacle Heteralepas canci on a continental slope at a depth of 229 m off Cape Nomamisaki in southern Japan. We developed a rearing method for the barnacles and studied their growth and reproduction at different food levels in the laboratory. A total of 136 individual H. canci were fed with Artemia salina larvae and brewer's yeast at three different food levels for 100 days. Both the growth and the ovary development were delayed when food availability was low, whereas the survival rate was lower at the high food level. In addition, an individual survived under complete starvation for 167 days. We concluded that H. canci has plastic life history traits that are adaptive for variable food availability.

  7. The influence of bacteria-dominated diets on Daphnia magna somatic growth, reproduction, and lipid composition.

    Science.gov (United States)

    Taipale, Sami J; Brett, Michael T; Pulkkinen, Katja; Kainz, Martin J

    2012-10-01

    We explored how dietary bacteria affect the life history traits and biochemical composition of Daphnia magna, using three bacteria taxa with very different lipid composition. Our objectives were to (1) examine whether and how bacteria-dominated diets affect Daphnia survival, growth, and fecundity, (2) see whether bacteria-specific fatty acid (FA) biomarkers accrued in Daphnia lipids, and (3) explore the quantitative relationship between bacteria availability in Daphnia diets and the amounts of bacterial FA in their lipids. Daphnia were fed monospecific and mixed diets of heterotrophic (Micrococcus luteus) or methanotrophic bacteria (Methylomonas methanica and Methylosinus trichosporium) and two phytoplankton species (Cryptomonas ozolinii and Scenedesmus obliquus). Daphnia neonates fed pure bacteria diets died after 6-12 days and produced no viable offspring, whereas those fed pure phytoplankton diets had high survival, growth, and reproduction success. Daphnia fed a mixed diet with 80% M. luteus and 20% of either phytoplankton had high somatic growth, but low reproduction. Conversely, Daphnia fed mixed diets including 80% of either methane-oxidizing bacteria and 20% Cryptomonas had high reproduction rates, but low somatic growth. All Daphnia fed mixed bacteria and phytoplankton diets had strong evidence of both bacteria- and phytoplankton-specific FA biomarkers in their lipids. FA mixing model calculations indicated that Daphnia that received 80% of their carbon from bacteria assimilated 46 ± 25% of their FA from this source. A bacteria-phytoplankton gradient experiment showed a strong positive correlation between the proportions of the bacterial FA in the Daphnia and their diet, indicating that bacterial utilization can be traced in this keystone consumer using FA biomarkers. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  8. Flexibility in the duration of parental care: Female leopards prioritise cub survival over reproductive output.

    Science.gov (United States)

    Balme, Guy A; Robinson, Hugh S; Pitman, Ross T; Hunter, Luke T B

    2017-09-01

    Deciding when to terminate care of offspring is a key consideration for parents. Prolonging care may increase fitness of current offspring, but it can also reduce opportunities for future reproduction. Despite its evolutionary importance, few studies have explored the optimal duration of parental care, particularly among large carnivores. We used a 40-year dataset to assess the trade-offs associated with the length of maternal care in leopards in the Sabi Sand Game Reserve, South Africa. We compared the costs imposed by care on the survival and residual reproductive value of leopard mothers against the benefits derived from maternal care in terms of increased offspring survival, recruitment and reproduction. We also examined the demographic and ecological factors affecting the duration of care in the light of five explanatory hypotheses: litter size, sex allocation, resource limitation, timing of independence and terminal investment. Duration of care exhibited by female leopards varied markedly, from 9 to 35 months. Mothers did not appear to suffer any short- or long-term survival costs from caring for cubs, but extending care reduced the number of litters that mothers could produce during their lifetimes. Interestingly, the duration of care did not appear to affect the post-independence survival or reproductive success of offspring (although it may have indirectly affected offspring survival by influencing dispersal distance). However, results from generalised linear mixed models showed that mothers prolonged care during periods of prey scarcity, supporting the resource limitation hypothesis. Female leopards also cared for sons longer than daughters, in line with the sex-allocation hypothesis. Cub survival is an important determinant of the lifetime reproductive success in leopards. By buffering offspring against environmental perturbation without jeopardising their own survivorship, female leopards apparently "hedge their bets" with current offspring rather than

  9. A size-structured model of bacterial growth and reproduction.

    Science.gov (United States)

    Ellermeyer, S F; Pilyugin, S S

    2012-01-01

    We consider a size-structured bacterial population model in which the rate of cell growth is both size- and time-dependent and the average per capita reproduction rate is specified as a model parameter. It is shown that the model admits classical solutions. The population-level and distribution-level behaviours of these solutions are then determined in terms of the model parameters. The distribution-level behaviour is found to be different from that found in similar models of bacterial population dynamics. Rather than convergence to a stable size distribution, we find that size distributions repeat in cycles. This phenomenon is observed in similar models only under special assumptions on the functional form of the size-dependent growth rate factor. Our main results are illustrated with examples, and we also provide an introductory study of the bacterial growth in a chemostat within the framework of our model.

  10. Delayed reproductive death as a dominant phenotype in cell clones surviving X-irradiation

    International Nuclear Information System (INIS)

    Chang, W.P.; Little, J.B.

    1992-01-01

    Residual damage manifested as reduced cloning efficiency was observed in many of the cloned progeny of Chinese hamster ovary (CHO) cells and human carcinoma SQ-20B cells surviving X-irradiation. This stable phenotype, which we have termed delayed reproductive death, persisted for >50 generations of cell replication post-irradiation. Clones showing this phenotype were aneuploid, and formed colonies with a high proportion of giant cells. By somatic cell hybridization of CHO clones, the delayed reproductive death phenotype was found to be a dominant trait; the cloning efficiency of hybrid clones was persistently depressed, as compared with that of control hybrid cells. These results suggest that delayed reproductive death represents a specific cellular response that may persist in some of the progeny of mammalian cells for long periods after X-irradiation. (author)

  11. Nerve Growth Factor in Cancer Cell Death and Survival

    Energy Technology Data Exchange (ETDEWEB)

    Molloy, Niamh H.; Read, Danielle E.; Gorman, Adrienne M., E-mail: adrienne.gorman@nuigalway.ie [Apoptosis Research Centre, School of Natural Sciences, National University of Ireland, Galway (Ireland)

    2011-02-01

    One of the major challenges for cancer therapeutics is the resistance of many tumor cells to induction of cell death due to pro-survival signaling in the cancer cells. Here we review the growing literature which shows that neurotrophins contribute to pro-survival signaling in many different types of cancer. In particular, nerve growth factor, the archetypal neurotrophin, has been shown to play a role in tumorigenesis over the past decade. Nerve growth factor mediates its effects through its two cognate receptors, TrkA, a receptor tyrosine kinase and p75{sup NTR}, a member of the death receptor superfamily. Depending on the tumor origin, pro-survival signaling can be mediated by TrkA receptors or by p75{sup NTR}. For example, in breast cancer the aberrant expression of nerve growth factor stimulates proliferative signaling through TrkA and pro-survival signaling through p75{sup NTR}. This latter signaling through p75{sup NTR} promotes increased resistance to the induction of cell death by chemotherapeutic treatments. In contrast, in prostate cells the p75{sup NTR} mediates cell death and prevents metastasis. In prostate cancer, expression of this receptor is lost, which contributes to tumor progression by allowing cells to survive, proliferate and metastasize. This review focuses on our current knowledge of neurotrophin signaling in cancer, with a particular emphasis on nerve growth factor regulation of cell death and survival in cancer.

  12. Nerve Growth Factor in Cancer Cell Death and Survival

    International Nuclear Information System (INIS)

    Molloy, Niamh H.; Read, Danielle E.; Gorman, Adrienne M.

    2011-01-01

    One of the major challenges for cancer therapeutics is the resistance of many tumor cells to induction of cell death due to pro-survival signaling in the cancer cells. Here we review the growing literature which shows that neurotrophins contribute to pro-survival signaling in many different types of cancer. In particular, nerve growth factor, the archetypal neurotrophin, has been shown to play a role in tumorigenesis over the past decade. Nerve growth factor mediates its effects through its two cognate receptors, TrkA, a receptor tyrosine kinase and p75 NTR , a member of the death receptor superfamily. Depending on the tumor origin, pro-survival signaling can be mediated by TrkA receptors or by p75 NTR . For example, in breast cancer the aberrant expression of nerve growth factor stimulates proliferative signaling through TrkA and pro-survival signaling through p75 NTR . This latter signaling through p75 NTR promotes increased resistance to the induction of cell death by chemotherapeutic treatments. In contrast, in prostate cells the p75 NTR mediates cell death and prevents metastasis. In prostate cancer, expression of this receptor is lost, which contributes to tumor progression by allowing cells to survive, proliferate and metastasize. This review focuses on our current knowledge of neurotrophin signaling in cancer, with a particular emphasis on nerve growth factor regulation of cell death and survival in cancer

  13. The self-perceived survival ability and reproductive fitness (SPFit) theory of substance use disorders.

    Science.gov (United States)

    Newlin, David B

    2002-04-01

    A new theory of substance use disorders is proposed-the SPFit theory-that is based on evolutionary biology and adaptive systems. Self-perceived survival ability and reproductive fitness (SPFit) is proposed as a human psychobiological construct that prioritizes and organizes (i.e. motivates) behavior, but is highly vulnerable to temporary, artificial activation by drugs of abuse. Autoshaping/sign-tracking/feature positive phenomena are proposed to underlie the development of craving and expectations about drugs as the individual learns that abused drugs will easily and reliably inflate SPFit. The cortico-mesolimbic dopamine system and its modulating interconnections are viewed as the biological substrate of SPFit; it is proposed to be a survival and reproductive motivation system rather than a reward center or reward pathway. Finally, the concept of modularity of mind is applied to the SPFit construct. Although considerable empirical data are consistent with the theory, new research is needed to test specific hypotheses derived from SPFit theory.

  14. Body Condition Indices Predict Reproductive Success but Not Survival in a Sedentary, Tropical Bird.

    Directory of Open Access Journals (Sweden)

    Olga Milenkaya

    Full Text Available Body condition may predict individual fitness because those in better condition have more resources to allocate towards improving their fitness. However, the hypothesis that condition indices are meaningful proxies for fitness has been questioned. Here, we ask if intraspecific variation in condition indices predicts annual reproductive success and survival. We monitored a population of Neochmia phaeton (crimson finch, a sedentary, tropical passerine, for reproductive success and survival over four breeding seasons, and sampled them for commonly used condition indices: mass adjusted for body size, muscle and fat scores, packed cell volume, hemoglobin concentration, total plasma protein, and heterophil to lymphocyte ratio. Our study population is well suited for this research because individuals forage in common areas and do not hold territories such that variation in condition between individuals is not confounded by differences in habitat quality. Furthermore, we controlled for factors that are known to impact condition indices in our study population (e.g., breeding stage such that we assessed individual condition relative to others in the same context. Condition indices that reflect energy reserves predicted both the probability of an individual fledging young and the number of young produced that survived to independence, but only during some years. Those that were relatively heavy for their body size produced about three times more independent young compared to light individuals. That energy reserves are a meaningful predictor of reproductive success in a sedentary passerine supports the idea that energy reserves are at least sometimes predictors of fitness. However, hematological indices failed to predict reproductive success and none of the indices predicted survival. Therefore, some but not all condition indices may be informative, but because we found that most indices did not predict any component of fitness, we question the ubiquitous

  15. Body Condition Indices Predict Reproductive Success but Not Survival in a Sedentary, Tropical Bird.

    Science.gov (United States)

    Milenkaya, Olga; Catlin, Daniel H; Legge, Sarah; Walters, Jeffrey R

    2015-01-01

    Body condition may predict individual fitness because those in better condition have more resources to allocate towards improving their fitness. However, the hypothesis that condition indices are meaningful proxies for fitness has been questioned. Here, we ask if intraspecific variation in condition indices predicts annual reproductive success and survival. We monitored a population of Neochmia phaeton (crimson finch), a sedentary, tropical passerine, for reproductive success and survival over four breeding seasons, and sampled them for commonly used condition indices: mass adjusted for body size, muscle and fat scores, packed cell volume, hemoglobin concentration, total plasma protein, and heterophil to lymphocyte ratio. Our study population is well suited for this research because individuals forage in common areas and do not hold territories such that variation in condition between individuals is not confounded by differences in habitat quality. Furthermore, we controlled for factors that are known to impact condition indices in our study population (e.g., breeding stage) such that we assessed individual condition relative to others in the same context. Condition indices that reflect energy reserves predicted both the probability of an individual fledging young and the number of young produced that survived to independence, but only during some years. Those that were relatively heavy for their body size produced about three times more independent young compared to light individuals. That energy reserves are a meaningful predictor of reproductive success in a sedentary passerine supports the idea that energy reserves are at least sometimes predictors of fitness. However, hematological indices failed to predict reproductive success and none of the indices predicted survival. Therefore, some but not all condition indices may be informative, but because we found that most indices did not predict any component of fitness, we question the ubiquitous interpretation of

  16. The self-perceived survival ability and reproductive fitness (SPFit) theory of substance use disorders

    OpenAIRE

    Newlin, David B.

    2002-01-01

    A new theory of substance use disorders is proposed—the SPFit theory—that is based on evolutionary biology and adaptive systems. Self‐perceived survival ability and reproductive fitness (SPFit) is proposed as a human psychobiological construct that prioritizes and organizes (i.e. motivates) behavior, but is highly vulnerable to temporary, artificial activation by drugs of abuse. Autoshaping/ sign‐tracking/feature positive phenomena are proposed to underlie the development of craving and expec...

  17. Deciphering the Costs of Reproduction in Mango – Vegetative Growth Matters

    Science.gov (United States)

    Capelli, Mathilde; Lauri, Pierre-Éric; Normand, Frédéric

    2016-01-01

    Irregular fruit production across successive years is a major issue that limits the profitability of most temperate and tropical fruit crops. It is particularly affected by the reciprocal relationships between vegetative and reproductive growth. The concept of the costs of reproduction is defined in terms of losses in the potential future reproductive success caused by current investment in reproduction. This concept, developed in ecology and evolutionary biology, could provide a methodological framework to analyze irregular bearing in fruit crops, especially in relation to the spatial scale at which studies are done. The objective of this study was to investigate the direct effects of reproduction during a growing cycle on reproduction during the following growing cycle and the indirect effects through vegetative growth between these two reproductive events, for four mango cultivars and during two growing cycles. Two spatial scales were considered: the growth unit (GU) and the scaffold branch. Costs of reproduction were detected between two successive reproductive events and between reproduction and vegetative growth. These costs were scale-dependent, generally detected at the GU scale and infrequently at the scaffold branch scale, suggesting partial branch autonomy with respect to processes underlying the effects of reproduction on vegetative growth. In contrast, the relationships between vegetative growth and reproduction were positive at the GU scale and at the scaffold branch scale in most cases, suggesting branch autonomy for the processes, mainly local, underlying flowering and fruiting. The negative effect of reproduction on vegetative growth prevailed over the positive effect of vegetative growth on the subsequent reproduction. The costs of reproduction were also cultivar-dependent. Those revealed at the GU scale were related to the bearing behavior of each cultivar. Our results put forward the crucial role of vegetative growth occurring between two

  18. Plant Growth-Promoting Rhizobacteria Stimulate Vegetative Growth and Asexual Reproduction of Kalanchoe daigremontiana.

    Science.gov (United States)

    Park, Yong-Soon; Park, Kyungseok; Kloepper, Joseph W; Ryu, Choong-Min

    2015-09-01

    Certain bacterial species associate with plant roots in soil. The plant growth-promoting rhizobacteria (PGPR) stimulate plant growth and yield in greenhouse and field. Here, we examined whether application of known bacilli PGPR strains stimulated growth and asexual reproduction in the succulent plant Kalanchoe daigremontiana. Four PGPR strains B. amyloliquefaciens IN937a, B. cereus BS107, B. pumilus INR7, and B. subtilis GB03 were applied to young plantlets by soil-drenching, and plant growth and development was monitored for three months. Aerial growth was significantly stimulated in PGPR-inoculated plants, which was observed as increases in plant height, shoot weight, and stem width. The stimulated growth influenced plant development by increasing the total number of leaves per plant. Treatment with bacilli also increased the total root biomass compared with that of control plants, and led to a 2-fold increase in asexual reproduction and plantlet formation on the leaf. Collectively, our results firstly demonstrate that Bacillus spp. promote vegetative development of K. daigremontiana, and the enhanced growth stimulates asexual reproduction and plantlet formation.

  19. Plant Growth-Promoting Rhizobacteria Stimulate Vegetative Growth and Asexual Reproduction of Kalanchoe daigremontiana

    Directory of Open Access Journals (Sweden)

    Yong-Soon Park

    2015-09-01

    Full Text Available Certain bacterial species associate with plant roots in soil. The plant growth-promoting rhizobacteria (PGPR stimulate plant growth and yield in greenhouse and field. Here, we examined whether application of known bacilli PGPR strains stimulated growth and asexual reproduction in the succulent plant Kalanchoe daigremontiana. Four PGPR strains B. amyloliquefaciens IN937a, B. cereus BS107, B. pumilus INR7, and B. subtilis GB03 were applied to young plantlets by soil-drenching, and plant growth and development was monitored for three months. Aerial growth was significantly stimulated in PGPR-inoculated plants, which was observed as increases in plant height, shoot weight, and stem width. The stimulated growth influenced plant development by increasing the total number of leaves per plant. Treatment with bacilli also increased the total root biomass compared with that of control plants, and led to a 2-fold increase in asexual reproduction and plantlet formation on the leaf. Collectively, our results firstly demonstrate that Bacillus spp. promote vegetative development of K. daigremontiana, and the enhanced growth stimulates asexual reproduction and plantlet formation.

  20. Drought effects on reproductive and growth characteristics in seed orchards

    International Nuclear Information System (INIS)

    Varol, T.; Ozel, H. B.; Bilir, N.

    2017-01-01

    Global climate change is one of the most important environmental problems, and it is also known that this change will lead to negative effects such as drought and increase in global temperature. This change is also estimated to increase its episodic effects negatively on growth and reproduction of the forest trees. In order to estimate the episodic or continuous effects of the drought, it is necessary to carry out studies based on long-term data. One of these studies are the investigation to be carried out on seed orchards that are one of the most important seed resources in forestry. Within this context, in this study, we determined to the reproductive and growth responses of the clones to the drought that continued in the most drought season (2012) for 2 subsequent years along with 65-year climate data for Red Pine (Pinus brutia Ten.) and Taurus Cedar (Cedrus libani Rich.). The relationships of SPEI values with seed characteristics and cone production were examined by using Spearman Correlation Analysis. According to the results obtained from this study, it was found that the severe drought was effected the reproductive characteristics of both of red pine and cedar. The effect of drought on the number of cone (r=-0.810, P=0.022) in red pine and on the number of 1-year-old cones (r=-0.40, P=0.027) and on cone moisture (r=-0.715, P=0.022) in cedar was quite evident. These results indicate that approximately 65% of the change in number of cone in Red Pine and approximately 51% of the change in moisture content of the cones in cedar can be explained with the drought. From the data, it is clear that the drought is effective on the cone yield and seed characteristics in seed orchards of both of Red Pine and Taurus Cedar species. (author)

  1. Individual heterogeneity and offspring sex affect the growth-reproduction trade-off in a mammal with indeterminate growth.

    Science.gov (United States)

    Gélin, Uriel; Wilson, Michelle E; Cripps, Jemma; Coulson, Graeme; Festa-Bianchet, Marco

    2016-04-01

    Reproduction can lead to a trade-off with growth, particularly when individuals reproduce before completing body growth. Kangaroos have indeterminate growth and may always face this trade-off. We combined an experimental manipulation of reproductive effort and multi-year monitoring of a large sample size of marked individuals in two populations of eastern grey kangaroos to test the predictions (1) that reproduction decreases skeletal growth and mass gain and (2) that mass loss leads to reproductive failure. We also tested if sex-allocation strategies influenced these trade-offs. Experimental reproductive suppression revealed negative effects of reproduction on mass gain and leg growth from 1 year to the next. Unmanipulated females, however, showed a positive correlation between number of days lactating and leg growth over periods of 2 years and longer, suggesting that over the long term, reproductive costs were masked by individual heterogeneity in resource acquisition. Mass gain was necessary for reproductive success the subsequent year. Although mothers of daughters generally lost more mass than females nursing sons, mothers in poor condition experienced greater mass gain and arm growth if they had daughters than if they had sons. The strong links between individual mass changes and reproduction suggest that reproductive tactics are strongly resource-dependent.

  2. Rainfall during parental care reduces reproductive and survival components of fitness in a passerine bird.

    Science.gov (United States)

    Öberg, Meit; Arlt, Debora; Pärt, Tomas; Laugen, Ane T; Eggers, Sönke; Low, Matthew

    2015-01-01

    Adverse weather conditions during parental care may have direct consequences for offspring production, but longer-term effects on juvenile and parental survival are less well known. We used long-term data on reproductive output, recruitment, and parental survival in northern wheatears (Oenanthe oenanthe) to investigate the effects of rainfall during parental care on fledging success, recruitment success (juvenile survival), and parental survival, and how these effects related to nestling age, breeding time, habitat quality, and parental nest visitation rates. While accounting for effects of temperature, fledging success was negatively related to rainfall (days > 10 mm) in the second half of the nestling period, with the magnitude of this effect being greater for breeding attempts early in the season. Recruitment success was, however, more sensitive to the number of rain days in the first half of the nestling period. Rainfall effects on parental survival differed between the sexes; males were more sensitive to rain during the nestling period than females. We demonstrate a probable mechanism driving the rainfall effects on reproductive output: Parental nest visitation rates decline with increasing amounts of daily rainfall, with this effect becoming stronger after consecutive rain days. Our study shows that rain during the nestling stage not only relates to fledging success but also has longer-term effects on recruitment and subsequent parental survival. Thus, if we want to understand or predict population responses to future climate change, we need to consider the potential impacts of changing rainfall patterns in addition to temperature, and how these will affect target species' vital rates.

  3. Reproductive performance and survival of Holstein and Holstein × Simmental crossbred cows.

    Science.gov (United States)

    Knob, Deise Aline; Alessio, Dileta Regina Moro; Thaler Neto, Andre; Mozzaquatro, Fabrício Desconsi

    2016-10-01

    Crossbreed dairy breeds, such as Holstein × dairy type of Simmental, have been generally used to improve fertility, udder health, and longevity of dairy herds. The aim was to compare the reproductive performance and survival of Holstein and Holstein × Simmental crossbred cows. Data from two farms were used as follows: one located in Bom Retiro, in the state of Santa Catarina, Brazil. and another in Carambeí, Paraná state. Information concerning birth, inseminations, and parity date were obtained from the management software of the farms, generating information regarding the calving interval, days between calving to first service, conception rate, and age at first calving. At one of the farms, calving was monitoring to quantify dystocia. Live weight as well as body condition score (BCS) of cows and information of culling were obtained to determine the survival rate. Data were analyzed by variance analysis and by logistic regression. Crossbred Holstein × Simmental cows had better reproductive performance than the Holstein cows, characterized by lower calving interval (381 vs. 445 days), higher conception rate (37.3 vs. 33.6 %), and shorter calving to first service interval (65 vs. 89 days). These results were related to a higher BCS in crossbred cows (3.63 vs. 2.94 points). Crossbred Holstein × Simmental cows had higher survival rate than Holstein cows on the second parity (83 vs. 92 %). No differences between genetic groups were observed (P > 0.05) for body weight and dystocia. In conclusion, Holstein × Simmental crossbred cows have better reproductive performance and higher survival rate than Holstein cows.

  4. Parental care improves offspring survival and growth in burying beetles

    Science.gov (United States)

    Eggert; Reinking; MULLER

    1998-01-01

    Burying beetles (genus Nicrophorus) provide elaborate parental care to their offspring. Parental beetles defend a small vertebrate carcass, which constitutes the sole food source for the larvae. They also manipulate the carcass in various ways and directly regurgitate pre-digested carrion to the young. The benefits of carcass manipulation and regurgitation have been the subject of a few small-scale studies that have yielded conflicting results. In this study, we investigated the benefits of these behaviours and tested for possible beneficial effects on larval survival rates and final body mass in N. vespilloides. In this species: (1) larval survival and mass were significantly higher in broods receiving parental care throughout larval development on the carcass than in broods developing in the absence of adults; (2) parental presence immediately subsequent to larval hatching greatly improved larval survival rates; (3) continued parental presence for several days further improved larval growth, leading to a greater final mass of individual larvae; (4) larval survival and growth were improved by parental preparation of carcasses and by an excision made in the integument of the carcass surface by the parents that allows the larvae ready access to their food; (5) positive effects of parental feeding on larval survival and growth were not mediated by the transfer of symbionts. Copyright 1998 The Association for the Study of Animal Behaviour.

  5. An evolutionary concept of polycystic ovarian disease: does evolution favour reproductive success over survival?

    Science.gov (United States)

    Gleicher, Norbert; Barad, David

    2006-05-01

    Polycystic ovarian disease (PCOD) is currently considered as possibly the most frequent cause of female infertility. It is also closely associated with syndrome XX, which, in turn, is closely linked with premature and excessive mortality. Considering these adverse effects on reproductive success and human survival, the evolutionary survival of PCOD, itself considered by many to be a genetically transmitted condition, would, on first glance, appear surprising, since evolution usually discriminates against both of these traits. However, an analysis of some recently reported characteristics of the condition calls for the reconsideration of PCOD as a condition which, from an evolutionary viewpoint, favours decreased reproductive success. Indeed, the reported observations that patients with PCOD will resume spontaneous ovulation with even relatively minor weight loss, and experience later menopause than controls, suggests exactly the opposite. Under an evolutionary concept, PCOD can thus be seen as a 'fertility storage condition' which in fact favours human reproductive success and allows the human species to maintain fertility even during adverse environmental circumstances, such as famines.

  6. Growth performance and survival of local and white leghorn chicken ...

    African Journals Online (AJOL)

    This study was conducted to evaluate the comparative growth, sexual maturity, survival, and feed utilization efficiency of local and White Leghorn chicken under intensive management condition. Five groups of each of the two breeds, with 200 baby chicks each, were subjected to appetite feeding with commercial layer\\'s ...

  7. Effect of inulin and probiotic bacteria on growth, survival, immune ...

    African Journals Online (AJOL)

    The effect of inulin and probiotic bacteria on the growth, survival, immune response and viral prevalence of white spot syndrome virus (WSSV) in white shrimp was evaluated. Presumptive bacilli and lactic acid bacteria (LAB) were characterized for hemolytic and enzymatic activity, hydrophobicity and antagonism against ...

  8. Grass defoliation affecting survival and growth of seedlings of ...

    African Journals Online (AJOL)

    Two experiments were conducted, one in the field and the other in the greenhouse, to investigate the effects of the intensity and frequency of grass defoliation on the survival and growth of Acacia karroo seedlings. In the greenhouse, seedlings growing with heavily clipped grasses had higher biomass production than those ...

  9. Coral restoration Bonaire : an evaluation of growth, regeneration and survival

    NARCIS (Netherlands)

    Meesters, H.W.G.; Boomstra, B.; Hurtado-Lopez, N.; Montbrun, A.; Virdis, F.

    2015-01-01

    The Coral restoration of Staghorn (Acropora cervicornis) and Elkhorn (A. palmata) as practiced by the Coral Restoration Foundation Bonaire (CRFB) is shown to be highly successful in terms of growth and survival of new colonies, in both nurseries and transplant locations. Coral restoration is

  10. Comparative study on growth and survival of larval and juvenile ...

    African Journals Online (AJOL)

    The total fatty acid and total unsaturated fatty acid in the algae significantly increased (P < 0.001) for ch1, D1, N1 and T1 taking into consideration that the state of C22:6 significantly increased. The ch1 gave better growth and survival percentage followed by D1 for enrich Brachionus plicatilis and newly hatched Artemia.

  11. Survival, growth, wood basic density and wood biomass of seven ...

    African Journals Online (AJOL)

    A performance comparison of seven-year-old individuals of 13 Casuarina species/provenances in terms of survival, growth (diameter, height and volume), wood basic density and wood biomass was undertaken at Kongowe, Kibaha, Tanzania. The trial was laid out using a randomised complete block design with four ...

  12. Survival and growth of epiphytic ferns depend on resource sharing

    Directory of Open Access Journals (Sweden)

    Hua-Zheng eLu

    2016-03-01

    Full Text Available Locally available resources can be shared within clonal plant systems through physiological integration, thus enhancing their survival and growth. Most epiphytes exhibit clonal growth habit, but few studies have tested effects of physiological integration (resource sharing on survival and growth of epiphytes and whether such effects vary with species. We conducted two experiments, one on individuals (single ramets and another on groups (several ramets within a plot, with severed and intact rhizome treatments (without and with physiological integration on two dominant epiphytic ferns (Polypodiodes subamoena and Lepisorus scolopendrium in a subtropical montane moist forest in Southwest China. Rhizome severing (preventing integration significantly reduced ramet survival in the individual experiment and number of surviving ramets in the group experiment, and it also decreased biomass of both species in both experiments. However, the magnitude of such integration effects did not vary significantly between the two species. We conclude that resource sharing may be a general strategy for clonal epiphytes to adapt to forest canopies where resources are limited and heterogeneously distributed in space and time.

  13. Endocrine phenotype, reproductive success and survival in the great tit, Parus major.

    Science.gov (United States)

    Ouyang, J Q; Sharp, P; Quetting, M; Hau, M

    2013-09-01

    A central goal in evolutionary ecology is to characterize and identify selection patterns on the optimal phenotype in different environments. Physiological traits, such as hormonal responses, provide important mechanisms by which individuals can adapt to fluctuating environmental conditions. It is therefore expected that selection shapes hormonal traits, but the strength and the direction of selection on plastic hormonal signals are still under investigation. Here, we determined whether, and in which way, selection is acting on the hormones corticosterone and prolactin by characterizing endocrine phenotypes and their relationship with fitness in free-living great tits, Parus major. We quantified variation in circulating concentrations of baseline and stress-induced corticosterone and in prolactin during the prebreeding (March) and the breeding season (May) for two consecutive years, and correlated these with reproductive success (yearly fledgling number) and overwinter survival in female and male individuals. In both years, individuals with high baseline corticosterone concentrations in March had the highest yearly fledgling numbers; while in May, individuals with low baseline corticosterone had the highest yearly reproductive success. Likewise, individuals that displayed strong seasonal plasticity in baseline corticosterone concentrations (high in March and low in May) had the highest reproductive success in each year. Prolactin concentrations were not related to reproductive success, but were positively correlated to the proximity to lay. Between-year plasticity in stress-induced corticosterone concentrations of males was related to yearly variation in food abundance, but not to overall reproductive success. These findings suggest that seasonally alternating directional selection is operating on baseline corticosterone concentrations in both sexes. The observed between-year consistency in selection patterns indicates that a one-time hormone sample in a given

  14. Growth and reproduction of the mangrove crab Goniopsis cruentata (Latreille, 1803) (Crustacea: Decapoda: Grapsidae) in southeastern Brazil.

    Science.gov (United States)

    Reis, Carla R G; Taddei, Fabiano G; Cobo, Valter J

    2015-01-01

    Goniopsis cruentata is a common semi-terrestrial crab in Brazilian mangroves and an important fishery resource for traditional communities in the northeastern Brazilian coast. Aiming to contribute to the knowledge about the species, this study evaluated the carapace width and weight growth curves, the relative growth of weight versus carapace width, and the temporal variation of gonadosomatic and hepatosomatic indices for the species. A total of 524 crabs were collected in a mangrove area of Ubatuba municipality, state of São Paulo. The growth-curves parameters and longevity (tmax) were estimated for males (CW∞=50.6 mm, WE=56.4 g, k=2.24, t0=0.003631502 year-1, tmax=1.3 years) and females (CW∞=50.7 mm, WE∞=58.8 g, k=2.50, t0=0.003247209 year-1, tmax=1.2 years). The age at onset of sexual maturity was 0.23 years for both genders. The weight-growth model was isometric for the immature developmental stages and allometric negative for adults. The species exhibited a continuous reproduction, with breeding peaks in spring and summer months. The weight dynamics of gonads and hepatopancreas were not clearly related. The growth and reproductive patterns indicated that Goniopsis cruentata has a life-history that prioritizes reproduction instead of survival. The species exhibited some of the highest growth rates and lowest longevity estimates reported for brachyuran species in Brazil.

  15. Growth and reproduction of the mangrove crab Goniopsis cruentata (Latreille, 1803 (Crustacea: Decapoda: Grapsidae in southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Carla R.G. Reis

    2015-06-01

    Full Text Available Goniopsis cruentata is a common semi-terrestrial crab in Brazilian mangroves and an important fishery resource for traditional communities in the northeastern Brazilian coast. Aiming to contribute to the knowledge about the species, this study evaluated the carapace width and weight growth curves, the relative growth of weight versus carapace width, and the temporal variation of gonadosomatic and hepatosomatic indices for the species. A total of 524 crabs were collected in a mangrove area of Ubatuba municipality, state of São Paulo. The growth-curves parameters and longevity (tmax were estimated for males (CW∞=50.6 mm, WE=56.4 g, k=2.24, t0=0.003631502 year-1, tmax=1.3 years and females (CW∞=50.7 mm, WE∞=58.8 g, k=2.50, t0=0.003247209 year-1, tmax=1.2 years. The age at onset of sexual maturity was 0.23 years for both genders. The weight-growth model was isometric for the immature developmental stages and allometric negative for adults. The species exhibited a continuous reproduction, with breeding peaks in spring and summer months. The weight dynamics of gonads and hepatopancreas were not clearly related. The growth and reproductive patterns indicated that Goniopsis cruentata has a life-history that prioritizes reproduction instead of survival. The species exhibited some of the highest growth rates and lowest longevity estimates reported for brachyuran species in Brazil.

  16. [Impact of new trend of ecological environment changes on growth, reproduction and diffusion of Oncomelania hupensis].

    Science.gov (United States)

    Juan, Xie; Li-Yong, Wen

    2016-03-07

    Oncomelania hupensis is the only intermediate host of Schistosoma japonicum , and the growth, reproduction and distribution of O.hupensis play an important role in schistosomiasis prevalence and transmission. This article reviews the influence of the new trend of ecological environment changes on the growth, reproduction and diffusion of the snails.

  17. Growth or reproduction: emergence of an evolutionary optimal strategy

    International Nuclear Information System (INIS)

    Grilli, J; Suweis, S; Maritan, A

    2013-01-01

    Modern ecology has re-emphasized the need for a quantitative understanding of the original ‘survival of the fittest theme’ based on analysis of the intricate trade-offs between competing evolutionary strategies that characterize the evolution of life. This is key to the understanding of species coexistence and ecosystem diversity under the omnipresent constraint of limited resources. In this work we propose an agent-based model replicating a community of interacting individuals, e.g. plants in a forest, where all are competing for the same finite amount of resources and each competitor is characterized by a specific growth–reproduction strategy. We show that such an evolution dynamics drives the system towards a stationary state characterized by an emergent optimal strategy, which in turn depends on the amount of available resources the ecosystem can rely on. We find that the share of resources used by individuals is power-law distributed with an exponent directly related to the optimal strategy. The model can be further generalized to devise optimal strategies in social and economical interacting systems dynamics. (paper)

  18. Optimal resource allocation to survival and reproduction in parasitic wasps foraging in fragmented habitats.

    Directory of Open Access Journals (Sweden)

    Eric Wajnberg

    Full Text Available Expansion and intensification of human land use represents the major cause of habitat fragmentation. Such fragmentation can have dramatic consequences on species richness and trophic interactions within food webs. Although the associated ecological consequences have been studied by several authors, the evolutionary effects on interacting species have received little research attention. Using a genetic algorithm, we quantified how habitat fragmentation and environmental variability affect the optimal reproductive strategies of parasitic wasps foraging for hosts. As observed in real animal species, the model is based on the existence of a negative trade-off between survival and reproduction resulting from competitive allocation of resources to either somatic maintenance or egg production. We also asked to what degree plasticity along this trade-off would be optimal, when plasticity is costly. We found that habitat fragmentation can indeed have strong effects on the reproductive strategies adopted by parasitoids. With increasing habitat fragmentation animals should invest in greater longevity with lower fecundity; yet, especially in unpredictable environments, some level of phenotypic plasticity should be selected for. Other consequences in terms of learning ability of foraging animals were also observed. The evolutionary consequences of these results are discussed.

  19. The survival-reproduction association becomes stronger when conditions are good.

    Science.gov (United States)

    Robert, Alexandre; Bolton, Mark; Jiguet, Frédéric; Bried, Joël

    2015-11-07

    Positive covariations between survival and reproductive performance (S-R covariation) are generally interpreted in the context of fixed or dynamic demographic heterogeneity (i.e. persistent differences between individuals, or dynamic variation in resource acquisition), but the processes underlying covariations are still unknown. We used multi-event modelling to investigate how environmental and individual features influence S-R covariation patterns in a long-lived seabird, the Monteiro's storm petrel (Oceanodroma monteiroi). Our analysis reveals that a strong positive association between individual breeding success and subsequent survival occurs only when conditions are favourable to reproduction (in favourable years, in high-quality nests and in nest-faithful breeders). This finding reflects differences in the main causes of breeding failure and mortality under favourable and unfavourable conditions, which in turn lead to distinct patterns of S-R covariation. We suggest, in particular, that resource-related sources of demographic heterogeneity do not generate a strong S-R covariation, in contrast with hidden and unpredictable sources of variation. © 2015 The Author(s).

  20. Bill redness is positively associated with reproduction and survival in male and female zebra finches.

    Directory of Open Access Journals (Sweden)

    Mirre J P Simons

    Full Text Available Sexual traits can serve as honest indicators of phenotypic quality when they are costly. Brightly coloured yellow to red traits, which are pigmented by carotenoids, are relatively common in birds, and feature in sexual selection. Carotenoids have been linked to immune and antioxidant function, and the trade-off between ornamentation and these physiological functions provides a potential mechanism rendering carotenoid based signals costly. Mutual ornamentation is also common in birds and can be maintained by mutual mate choice for this ornament or by a correlated response in one sex to selection on the other sex. When selection pressures differ between the sexes this can cause intralocus sexual conflict. Sexually antagonistic selection pressures have been demonstrated for few sexual traits, and for carotenoid-dependent traits there is a single example: bill redness was found to be positively associated with survival and reproductive output in male zebra finches, but negatively so in females. We retested these associations in our captive zebra finch population without two possible limitations of this earlier study. Contrary to the earlier findings, we found no evidence for sexually antagonistic selection. In both sexes, individuals with redder bills showed higher survival. This association disappeared among the females with the reddest bills. Furthermore, females with redder bills achieved higher reproductive output. We conclude that bill redness of male and female zebra finches honestly signals phenotypic quality, and discuss the possible causes of the differences between our results and earlier findings.

  1. Reproductive tactics optimizing the survival of the offspring of Cichlasoma orientale (Perciformes: Cichlidae).

    Science.gov (United States)

    Spíndola Linhares, Jussiara Candeira; Resende Manna, Luisa; Mazzoni, Rosana; Ferreira Rezende, Carla; Feitosa Silva, José Roberto

    2014-09-01

    High mortality rates have been observed in Teleost during early developmental stages, as well as great variations in reproductive tactics, which are related to adaptations towards environmental conditions and ecological niches for which different species have a specific response. The objective of this study was to describe reproductive tactics related to the survival of Cichlasoma orientale offspring, including aspects of body size, parental care, fecundity, oocyte size and spawning patterns. Samples were performed monthly from August 2011 to July 2013, in lentic and lotic environments at Curu river basin, Brazilian Northeastern semiarid region. Individual behavior (n = 13) was observed underwater for over 50 hours by ad libitum sampling and focal-animal sampling. Collected individuals (males n = 185, females n = 95) were evaluated regarding the standard length, batch fecundity, oocyte size and spawning pattern. In females with mature ovaries, oocyte groups at different developmental stages were observed, these cells were counted and measured, and fecundity was estimated by the gravimetric method. Our results showed that the species displayed biparental care behavior and, on average, males were larger than females. Based on 46 ovaries, the average batch fecundity was 2,052-849 (range: 254-3 389). Standard length and batch fecundity were positively correlated, but no correlation was found between oocyte size and standard length. The maximum diameter observed in the most developed oocytes was 1.8 mm. The observed distribution of oocyte size classes indicated synchronous oocyte development in three groups: pre- vitellogenic, vitellogenic and mature, showing that C. orientale is a multiple spawner. Differences in the amount of oocytes among the three groups were observed, with the most developed group showing the smallest number of oocytes. The combination of low fecundity and large egg size is characteristic of demersal spawners due to a greater environmental

  2. Reproductive tactics optimizing the survival of the offspring of Cichlasoma orientale (Perciformes: Cichlidae

    Directory of Open Access Journals (Sweden)

    Jussiara Candeira Spíndola Linhares

    2014-09-01

    Full Text Available High mortality rates have been observed in Teleost during early developmental stages, as well as great variations in reproductive tactics, which are related to adaptations towards environmental conditions and ecological niches for which different species have a specific response. The objective of this study was to describe reproductive tactics related to the survival of Cichlasoma orientale offspring, including aspects of body size, parental care, fecundity, oocyte size and spawning patterns. Samples were performed monthly from August 2011 to July 2013, in lentic and lotic environments at Curu river basin, Brazilian Northeastern semiarid region. Individual behavior (n=113 was observed underwater for over 50 hours by ad libitum sampling and focal-animal sampling. Collected individuals (males n=185, females n=95 were evaluated regarding the standard length, batch fecundity, oocyte size and spawning pattern. In females with mature ovaries, oocyte groups at different developmental stages were observed, these cells were counted and measured, and fecundity was estimated by the gravimetric method. Our results showed that the species displayed biparental care behavior and, on average, males were larger than females. Based on 46 ovaries, the average batch fecundity was 2 052±849 (range: 254-3 389. Standard length and batch fecundity were positively correlated, but no correlation was found between oocyte size and standard length. The maximum diameter observed in the most developed oocytes was 1.8mm. The observed distribution of oocyte size classes indicated synchronous oocyte development in three groups: previtellogenic, vitellogenic and mature, showing that C. orientale is a multiple spawner. Differences in the amount of oocytes among the three groups were observed, with the most developed group showing the smallest number of oocytes. The combination of low fecundity and large egg size is characteristic of demersal spawners due to a greater

  3. Survival benefits select for group living in a social spider despite reproductive costs

    DEFF Research Database (Denmark)

    Bilde, T.; Coates, K.S.; Birkhofer, K.

    2007-01-01

    The evolution of cooperation requires benefits of group living to exceed costs. Hence, some components of fitness are expected to increase with increasing group size, whereas others may decrease because of competition among group members. The social spiders provide an excellent system to investig......The evolution of cooperation requires benefits of group living to exceed costs. Hence, some components of fitness are expected to increase with increasing group size, whereas others may decrease because of competition among group members. The social spiders provide an excellent system...... to investigate the costs and benefits of group living: they occur in groups of various sizes and individuals are relatively short-lived, therefore life history traits and Lifetime Reproductive Success (LRS) can be estimated as a function of group size. Sociality in spiders has originated repeatedly...... and survival in the social spider Stegodyphus dumicola in two populations in Namibia. In both populations, the major benefit of group living was improved survival of colonies and late-instar juveniles with increasing colony size. By contrast, female fecundity, female body size and early juvenile survival...

  4. Effects of individual quality, reproductive success and environmental variability on survival of a long-lived seabird.

    Science.gov (United States)

    Lescroël, Amélie; Dugger, Katie M; Ballard, Grant; Ainley, David G

    2009-07-01

    1. Heterogeneity in individual quality (i.e. individuals having different performance levels that are consistent throughout life) can drive the demography of iteroparous species, but quality in the context of environmental variability has rarely been evaluated. 2. We investigated the demographic responses of a long-lived seabird, the Adélie penguin (Pygoscelis adeliae), to contrasting environmental conditions as a function of reproductive success, breeding quality (BQ) and experience. A continuous index of BQ (BQI) was developed to reflect an individual's ability, relative to others, to produce viable offspring. 3. First, we assessed the relative importance of costs of reproduction vs. heterogeneity in quality by comparing survival and reproductive probabilities among deferred, successful and unsuccessful breeders under 'demanding' conditions using multistate capture-mark-recapture modelling. Then, we quantified the influence of BQI on adult survival among experienced breeders vs. the whole study population under both 'normal' and 'demanding' conditions. 4. Higher survival rates were exhibited by successful (74-76%) compared to unsuccessful breeders (64%); the former also more frequently reproduced successfully at year t + 1. 5. From 1997 to 2006, adult survival ranged from 64-79%, with BQI accounting for 91% of variability in the entire study population, but only 17% in experienced breeders. The weakened relationship between BQI and survival in experienced breeders supports the theory that selection during the first reproductive event accounts for a more homogeneous pool of experienced breeders. 6. No significant effect of environmental covariates on survival was evident, suggesting that what appeared to be demanding conditions were within the range that could be buffered by this species. 7. For the first time in seabirds, a quadratic relationship between adult survival and BQI showed that adult survival is shaped by both heterogeneity in quality and reproductive

  5. Toxicity of four veterinary pharmaceuticals on the survival and reproduction of Folsomia candida in tropical soils.

    Science.gov (United States)

    Zortéa, Talyta; Segat, Julia C; Maccari, Ana Paula; Sousa, José Paulo; Da Silva, Aleksandro S; Baretta, Dilmar

    2017-04-01

    This study aimed to evaluate the effect of veterinary pharmaceuticals (VPs) used to control endo- and ectoparasites in ruminants, on the survival and reproduction of the collembolan species Folsomia candida. Standard ecotoxicological tests were conducted in Tropical Artificial Soil and the treatments consisted of increasing dosages of four commercial products with different active ingredients: ivermectin, fipronil, fluazuron and closantel. Ecotoxicological effects were related to the class and mode of action of the different compounds. Fipronil and ivermectin were the most toxic compounds causing a significant reduction in the number of juveniles at the lowest doses tested (LOEC reprod values of 0.3 and 0.2 mg kg -1 of dry soil, respectively) and similar low EC 50 values (fipronil: 0.19 mg kg -1 dry soil, CL 95% 0.16-0.22; ivermectin: 0.43 mg kg -1 dry soil, CL 95% 0.09-0.77), although the effects observed in the former compound were possibly related to a low adult survival (LC 50 of 0.62 mg kg -1 dry soil; CL 95% : 0.25-1.06). For the latter compound no significant lethal effects were observed. Fluazuron caused an intermediate toxicity (EC 50 of 3.07 mg kg -1 dry soil, CL 95% : 2.26-3.87), and also here a decrease in adult survival could explain the effects observed at reproduction. Closantel, despite showing a significant reduction on the number of juveniles produced, no dose-response relationship nor effects higher than 50% were observed. Overall, all tested compounds, especially ivermectin, when present in soil even at sub-lethal concentrations, can impair the reproduction of collembolans and possibly other arthropods. However, the actual risk to arthropod communities should be further investigated performing tests under a more realistic exposure (e.g., by testing the dung itself as the contaminated matrix) and by deriving ecotoxicologically relevant exposure concentration in soil derived from the presence of cattle dung. Copyright © 2017 Elsevier

  6. Effects of food stress on survival and reproductive performance of seabirds

    Science.gov (United States)

    Piatt, John F.; Kitaysky, Sasha

    2001-01-01

    Traditional field methods of assessing effects of fluctuations in food supply on the survival and reproductive performance of seabirds may give equivocal results. In this project we applied an additional tool: The measure of stress hormones in free-ranging seabirds. Food stress can be quantified by measuring base levels of stress hormones such as corticosterone in the blood of seabirds, or the rise in blood levels of corticosterone in response to a standardized stressor: capture, handling and restraint. We applied these techniques to seabirds breeding in Lower Cook Inlet and also used captive birds for controlled experiments. This study provided a unique opportunity for a concurrent field and captive study of the behavioral and physiological consequences of stress in seabirds. Moreover, this study provides the basis for management of seabird populations in the areas affected by the Exxon Valdez oil spill, which will have broader applications for seabird monitoring programs. This year represents production of a synthesis of the project.

  7. Extreme reproduction and survival of a true cliffhanger: the endangered plant, Borderea chouardii (Dioscoreaceae)

    DEFF Research Database (Denmark)

    García, M. B.; Espadaler, Xavier; Olesen, Jens Mogens

    2012-01-01

    self-sown seeds, and 1/3 was dispersed by ants, which gathered the seeds with their oil-rich elaiosome. Gravity played a minor role to dispersal. Both ant dispersal and self-sowing resulted in the same survival rate of seedlings. A double mutualism is a risky reproductive strategy, but B. chouardii...... aspects is extreme, especially the unusual double mutualistic role of ants as both pollinators and dispersers. We made a 2-year pollination census and four years of seed-dispersal experiments, recording flower visitors and dispersal rates. Fruit and seed set, self-sowing of seeds, seedling recruitment......, and fate of seedlings from seeds sowed by different agents were scored over a period of 17 years. The ants Lasius grandis and L. cinereus were the main pollinators, whereas another ant Pheidole pallidula dispersed seeds. Thus ants functioned as double mutualists. Two thirds of all new seedlings came from...

  8. Effects of a constructed Technosol on mortality, survival and reproduction of earthworms

    Science.gov (United States)

    Pey, Benjamin; Cortet, Jerome; Capowiez, Yvan; Mignot, Lenaic; Nahmani, Johanne; Watteau, Francoise; Schwartz, Christophe

    2010-05-01

    Soils, whose properties and pedogenesis are dominated by artificial materials or transported materials, are classified as Technosols. Some of these Technosols are used in soil engineering, which is the voluntary action to combine technical materials in a given objective to restore an ecosystem. Primary by products that are used to build these Technosols need to be assessed on an ecotoxicological point of view. The following study aims to assess the effects of a constructed Technosol made from different primary by-products on the mortality, survival and reproductions of two earthworm species. The model of Technosol used here is a combination of green-waste compost (GWC) and papermill sludge (PS) mixed with thermally treated industrial soil (TIS). OECD soil is used as a control soil. Three different experiments have been managed: i) the first, to assess the potential toxicity effect on Eisenia foetida biomass (28 days) and reproduction (56 days), ii) the second to assess the short-term effect (7 days) on Lumbricus terrestris biomass, iii) and the third to assess the medium-term effect (30 days) on L. terrestris biomass. Reproduction of E. foetida is enhanced with high proportions of GWC. For biomass, GWC seems to improve body mass contrary to other materials which lead to losses of body mass. Thus, for E. foetida, GWC seems to be a high-quality and long-term source of food. Body mass of L. terrestris decreased with GWC and OECD. At short-term only, TIS/PS leads to a gain of body mass. Only equilibrium of 25% GWC - 75% TIS/PS allows a gain of body mass at medium term. TIS/PS appears to be a low-quality and short-term food resource but an excellent water tank. It can be concluded that the constructed Technosol is not toxic for fauna but some differences appear between different tested material combinations, depending on nature, proportion and trophic properties of materials.

  9. Effect of gossypol on survival and reproduction of the zoophytophagous stinkbug Podisus nigrispinus (Dallas

    Directory of Open Access Journals (Sweden)

    Walter S. Evangelista Junior

    2011-06-01

    Full Text Available Effect of gossypol on survival and reproduction of the zoophytophagous stinkbug Podisus nigrispinus (Dallas. Gossypol is a sesquiterpene aldehyde found in cotton plants conferring resistance against herbivory. Although the effect of this sesquiterpenoid on insect pests of cotton is known, the interaction of this compound with zoophytophagous predators such as Podisus nigrispinus (Dallas (Hemiptera, Pentatomidae has not been studied so far. Thus, the objective of this study was to evaluate the effect of the purified gossypol on nymphs and adults of P. nigrispinus. Nymphs and adults of this predator were fed on Tenebrio molitor pupae and supplemented with solutions of gossypol at concentrations of 0.00, 0.05, 0.10, and 0.20% (w/v during the nymphal and adult stages or, only during the adult stage of P. nigrispinus. The nymphal stage of the predator was, on average, two days longer when suplemmented with gossypol. Emerged adults had lower fecundity and egg hatching, especially at the highest gossypol concentration (0.20% ingested during the nymphal and adult stages. However, this predator was not affected when it ingested the compound only during the adult stage. P. nigrispinus can have delayed nymphal development and lower reproductive performance when ingesting the gossypol during the nymphal and adult stages, but only at higher concentrations of gossypol than that produced by cotton plants.

  10. Environmental conditions shape the temporal pattern of investment in reproduction and survival.

    Science.gov (United States)

    Marasco, Valeria; Boner, Winnie; Griffiths, Kate; Heidinger, Britt; Monaghan, Pat

    2018-01-10

    The relationship between environmental stress exposure and ageing is likely to vary with stressor severity, life-history stage and the time scale over which effects are measured. Such factors could influence whether stress exposure accelerates or slows the ageing process, but their interactions have not previously been experimentally investigated. We found that experimental exposure of zebra finches to mildly challenging environmental circumstances from young to old adulthood, which increased exposure to stress hormones, reduced breeding performance during early adulthood, but had positive effects when individuals were bred in old adulthood. This difference was not due to selective mortality, because the effects were evident within individuals, and no evidence of habituation in the response to the stressor was found. The more stressful environment had no effects on survival during young or old adulthood, but substantially improved survival during middle age. Changes in the effects at different ages could be due to the duration and nature of the challenging exposure, or to variation in coping capacity or strategy with age. These results show that living under challenging environmental circumstances can influence ageing trajectories in terms of both reproductive performance and longevity. Our results provide experimental support for the emerging idea that stress exposure needs to be optimized rather than minimized to obtain the best health outcomes. © 2018 The Author(s).

  11. Abdominally implanted satellite transmitters affect reproduction and survival rather than migration of large shorebirds

    Science.gov (United States)

    Hooijmeijer, Jos C. E. W.; Gill, Robert E.; Mulcahy, Daniel M.; Tibbitts, T. Lee; Kentie, Rosemarie; Gerritsen, Gerrit J.; Bruinzeel, Leo W.; Tijssen, David C.; Harwood, Christopher M.; Piersma, Theunis

    2014-01-01

    Satellite telemetry has become a common technique to investigate avian life-histories, but whether such tagging will affect fitness is a critical unknown. In this study, we evaluate multi-year effects of implanted transmitters on migratory timing and reproductive performance in shorebirds. Shorebirds increasingly are recognized as good models in ecology and evolution. That many of them are of conservation concern adds to the research responsibilities. In May 2009, we captured 56 female Black-tailed Godwits Limosa limosa limosa during late incubation in The Netherlands. Of these, 15 birds were equipped with 26-g satellite transmitters with a percutaneous antenna (7.8 % ± 0.2 SD of body mass), surgically implanted in the coelom. We compared immediate nest survival, timing of migration, subsequent nest site fidelity and reproductive behaviour including egg laying with those of the remaining birds, a comparison group of 41 females. We found no effects on immediate nest survival. Fledging success and subsequent southward and northward migration patterns of the implanted birds conformed to the expectations, and arrival time on the breeding grounds in 2010–2012 did not differ from the comparison group. Compared with the comparison group, in the year after implantation, implanted birds were equally faithful to the nest site and showed equal territorial behaviour, but a paucity of behaviours indicating nests or clutches. In the 3 years after implantation, the yearly apparent survival of implanted birds was 16 % points lower. Despite intense searching, we found only three eggs of two implanted birds; all were deformed. A similarly deformed egg was reported in a similarly implanted Whimbrel Numenius phaeopus returning to breed in central Alaska. The presence in the body cavity of an object slightly smaller than a normal egg may thus lead to egg malformation and, likely, reduced egg viability. That the use of implanted satellite transmitters in these large shorebirds

  12. Environmental effects on growth, reproduction, and life-history traits of loggerhead turtles

    NARCIS (Netherlands)

    Marn, Nina; Jusup, Marko; Legović, Tarzan; Kooijman, S. A.L.M.; Klanjšček, Tin

    2017-01-01

    Understanding the relationship between the environmental conditions and life-history traits (such as growth, reproduction, and size at specific life stages) is important for understanding the population dynamics of a species and for constructing adaptable, relevant, and efficient conservation

  13. [Studies on the growth and reproduction of bacterial communities on structural materials of the international space station].

    Science.gov (United States)

    Rakova, N M; Svistunova, Iu V; Novikova, N D

    2005-01-01

    Probability of microbial growth and reproduction on the ISS interior and equipment materials varying in chemical composition was studied with the strains of Bacillus subtilis, Staphylococcus epidermidis, Staphylococcus saprophyticus, Pseudomonas putida etc. sampled from the ISS environment. Controls were ground reference strains of same bacterial species. Based on our results, some of the microorganisms are able to survive and proliferate on structural materials; the ability was greater in space isolates as compared with their ground analogs. The greatest ability to grow and proliferate on materials was demonstrated by Bacillus subtilis.

  14. Physiology and Endocrinology Symposium: The current status of heat shock in early embryonic survival and reproductive efficiency

    Science.gov (United States)

    The Physiology and Endocrinology Symposium entitled “The Current Status of Heat Shock in Early Embryonic Survival and Reproductive Efficiency” was held at the Joint ADSA-CSAS-AMPA-WSAS-ASAS Meeting in Phoenix, Arizona, July 15 to 19, 2012. In recent years, data has accumulated suggesting a role for...

  15. Effects of waterborne zinc on reproduction, survival and morphometrics of Gyrodactylus turnbulli (Monogenea) on guppies (Poecilia reticulata).

    Science.gov (United States)

    Gheorghiu, Cristina; Cable, Joanne; Marcogliese, David J; Scott, Marilyn E

    2007-03-01

    Recent reviews indicate that pollutants in the surrounding macroenvironment directly influence the population dynamics, distribution and dispersal of fish ectoparasites, often leading to increased parasitism. The aim of the current study was to explore the effects of sublethal concentrations of waterborne zinc (up to 240 microg Zn/L) on survival, reproduction and morphometrics of Gyrodactylus turnbulli, a viviparous monogenean infecting the skin and fins of the guppy, Poecilia reticulata. Parasite survival and reproduction on the fish were recorded daily for individual parasites maintained in isolated containers. Both survival and reproduction were reduced in 30 and 120 microg Zn/L, compared with 0, 15, and 60 microg Zn/L indicating direct toxic effects of Zn on the parasite. However, as generation time was unaffected by Zn, we attribute the reduced reproduction to the shorter lifespan. Parasite survival off the fish was monitored hourly. Average lifespan of the detached parasites decreased linearly from 19.5 h in 0 microg Zn/L to 17.3h in 240 microg Zn/L, further supporting the direct toxic effect of Zn to the parasite. In addition, temporal dynamics of parasite morphometrics were monitored from mini-epidemics sampled after 1, 5, 10, and 15 days exposure to various Zn concentrations. All morphological parameters decreased significantly in response both to concentration and duration of exposure to waterborne Zn. Together these data clearly indicate that concentrations as low as 120 microg Zn/L are directly toxic to G. turnbulli.

  16. Generation time, net reproductive rate, and growth in stage-age-structured populations

    DEFF Research Database (Denmark)

    Steiner, Uli; Tuljapurkar, Shripad; Coulson, Tim

    2014-01-01

    examples to show how reproductive timing Tc and level R0 are shaped by stage dynamics (individual trait changes), selection on the trait, and parent-offspring phenotypic correlation. We also show how population structure can affect dispersion in reproduction among ages and stages. These macroscopic...... to age-structured populations. Here we generalize this result to populations structured by stage and age by providing a new, unique measure of reproductive timing (Tc) that, along with net reproductive rate (R0), has a direct mathematical relationship to and approximates growth rate (r). We use simple...

  17. The dynamics of reproductive rate, offspring survivorship and growth in the lined seahorse, Hippocampus erectus Perry, 1810

    Directory of Open Access Journals (Sweden)

    Qiang Lin

    2012-02-01

    Seahorses are the vertebrate group with the embryonic development occurring within a special pouch in males. To understand the reproductive efficiency of the lined seahorse, Hippocampus erectus Perry, 1810 under controlled breeding experiments, we investigated the dynamics of reproductive rate, offspring survivorship and growth over births by the same male seahorses. The mean brood size of the 1-year old pairs in the 1st birth was 85.4±56.9 per brood, which was significantly smaller than that in the 6th birth (465.9±136.4 per brood (P<0.001. The offspring survivorship and growth rate increased with the births. The fecundity was positively correlated with the length of brood pouches of males and trunk of females. The fecundity of 1-year old male and 2-year old female pairs was significantly higher than that from 1-year old couples (P<0.001. The brood size (552.7±150.4 of the males who mated with females that were isolated for the gamete-preparation, was larger than those (467.8±141.2 from the long-term pairs (P<0.05. Moreover, the offspring from the isolated females had higher survival and growth rates. Our results showed that the potential reproductive rate of seahorses H. erectus increased with the brood pouch development.

  18. Impaired reproduction and individual growth of the water flea Daphnia magna as consequence of exposure to the non-ester pyrethroid etofenprox.

    Science.gov (United States)

    Sancho, Encarna; Banegas, Sandra; Villarroel, María José; Ferrando, Dolores

    2018-03-01

    The effect of the pesticide etofenprox (0.76, 0.95, 1.18, 1.48, and 1.85 μg L -1 ) on survival, reproduction, and growth of Daphnia magna organisms was monitored using 21-day exposure tests. In order to test pesticide effects on D. magna, survival, length, mean total neonates per female, mean brood size, time to first reproduction, mean number broods per female, cumulative molting, and the population parameter intrinsic rate of natural increase (r) were used. Reproduction was seriously affected by etofenprox. Concentrations of etofenprox higher than 1.18 μg L -1 affected all the reproductive parameters analyzed as well as individual length. However, daphnids' survival after 21 days of pesticide exposure did not exhibited differences among experimental and control groups. The no observed effect concentration (NOEC), the lowest observed effect concentration (LOEC), and the maximum acceptable toxicant concentration (MATC) were calculated for the different parameters. A MATC estimation of 1.32 μg L -1 was calculated for mean brood size, mean number of broods per female, mean number of neonates per female, and the intrinsic rate of growth population. Etofenprox effect on the algae Nannochloris oculata was also evaluated. The selected etofenprox concentrations did not affect algal growth rate (μ) after 24 h; however, N. oculata exposed during 48 and 72 h to the highest etofenprox concentration showed a decreased in its population rate.

  19. Conservation biological control in strawberry: effect of different pollen on development, survival, and reproduction of Neoseiulus californicus (Acari: Phytoseiidae).

    Science.gov (United States)

    Gugole Ottaviano, María F; Cédola, Claudia V; Sánchez, Norma E; Greco, Nancy M

    2015-12-01

    Wild vegetation surrounding crops may provide temporary habitat and potential food sources for phytoseiids in different seasons. Monthly vegetation samples of wild plants adjacent to strawberry plants and wild plants in a vegetation strip close to the crop were taken. The frequency of Neoseiulus californicus, Tetranychus urticae and other mites and insects was recorded. In addition, in a laboratory assay, the survival, developmental time and fecundity of females fed on pollen of strawberry and pollen of wild plants where N. californicus was recorded during their flowering, were estimated. Pollen from Urtica urens, Lamium amplexicaule, Convolvulus arvensis, Sonchus oleraceous, Galega officinalis, and Fragaria x ananassa (strawberry) allowed development of N. californicus to adult, but not reproduction. Survival was 70-80 % when fed on pollen from S. oleraceus, G. officinalis and C. arvensis, 80-90 % when fed on pollen from U. urens and F. x ananassa, and more than 90 % when fed on T. urticae and on pollen from L. amplexicaule. In autumn and winter, U. urens, L. amplexicaule and S. oleraceous could promote the persistence of N. californicus when prey density in strawberry is low, offering T. urticae, thrips and pollen. In summer, pollen of C. arvensis and G. officinalis would contribute to the persistence of N. californicus when the strawberry crop is ending and offers scarce food resources. Although the pollen of these plants would not enable the predator population to increase, the presence of these plants in the vicinity of strawberry could contribute to the persistence of N. californicus population and help to limit T. urticae growth when this pest begins to colonize the crop.

  20. Reproduction, growth, and tissue residues of deer fed dieldrin

    Science.gov (United States)

    Murphy, D.A.; Korschgen, L.J.

    1970-01-01

    Feeding tests were conducted from January, 1966, to January, 1969, to ascertain the effects of daily ingestions of sublethal amounts of dieldrin on white-tailed deer (Odocoileus virginianus). Groups of deer on 0 ppm dieldrin (controls), 5 ppm, and 25 ppm dieldrin were maintained at these respective levels, as were their progeny. Treated food was readily accepted. Dieldrin intoxication was not observed, and 9 of 10 animals of each group survived 3 years of treatment. No differences in conception or in utero mortality were found between groups. Fawns from dieldrin-fed does were smaller at birth and greater post-partum mortality occurred. Fertility of male progeny was not affected. Growth was slower and remained reduced in dieldrin-treated females which were immature when the study began. Hematologic values and serum protein concentrations were not significantly (P > 0.05) related to treatment. Liver/body weight ratios were significantly (P brain, liver, and thigh muscle tissues showed no evidence of increasing with length of treatment, but showed definite relationships to levels of dieldrin in daily diets. Nursing fawns had higher residues in brain tissues than did older deer on 5 ppm a d 25 ppm dieldrin. Highest brain residues (12.60 and 12.10 ppm, wet weight) occurred in fawns only a few days of age at death. Equilibrium between ingestion and storage or excretion of dieldrin occurred prior to 200 days and continued until nearly 1,100 days. There was no evidence of a sharp decline in residues after a long period of continued dosage. Daily ingestion of 100 and 200 ppm of dieldrin proved fatal to yearling male deer at 27 and 22 days, respectively.

  1. Fragmentation in the branching coral Acropora palmata (Lamarck): growth, survivorship, and reproduction of colonies and fragments.

    Science.gov (United States)

    Lirman

    2000-08-23

    Acropora palmata, a branching coral abundant on shallow reef environments throughout the Caribbean, is susceptible to physical disturbance caused by storms. Accordingly, the survivorship and propagation of this species are tied to its capability to recover after fragmentation. Fragments of A. palmata comprised 40% of ramets within populations that had experienced recent storms. While the survivorship of A. palmata fragments was not directly related to the size of fragments, removal of fragments from areas where they settled was influenced by size. Survivorship of fragments was also affected by type of substratum; the greatest mortality (58% loss within the first month) was observed on sand, whereas fragments placed on top of live colonies of A. palmata fused to the underlying tissue and did not experience any losses. Fragments created by Hurricane Andrew on a Florida reef in August 1992 began developing new growth (proto-branches) 7 months after the storm. The number of proto-branches on fragments was dependent on size, but growth was not affected by the size of fragments. Growth-rates of proto-branches increased exponentially with time (1.7 cm year(-1) for 1993-1994, 2.7 cm year(-1) for 1994-1995, 4.2 cm year(-1) for 1995-1996, and 6.5 cm year(-1) for 1996-1997), taking over 4 years for proto-branches to achieve rates comparable to those of adult colonies on the same reef (6.9 cm year(-1)). In addition to the initial mortality and reduced growth-rates, fragmentation resulted in a loss of reproductive potential. Neither colonies that experienced severe fragmentation nor fragments contained gametes until 4 years after the initial damage. Although A. palmata may survive periodic fragmentation, the long-term effects of this process will depend ultimately on the balance between the benefits and costs of this process.

  2. A survival-reproduction trade-off in entomopathogenic nematodes mediated by their bacterial symbionts.

    Science.gov (United States)

    Emelianoff, Vanya; Chapuis, Elodie; Le Brun, Nathalie; Chiral, Magali; Moulia, Catherine; Ferdy, Jean-Baptiste

    2008-04-01

    In this work, we investigate the investment of entomopathogenic Steinernema nematodes (Rhabditidae) in their symbiotic association with Xenorhabdus bacteria (Enterobacteriaceae). Their life cycle comprises two phases: (1) a free stage in the soil, where infective juveniles (IJs) of the nematode carry bacteria in a digestive vesicle and search for insect hosts, and (2) a parasitic stage into the insect where bacterial multiplication, nematode reproduction, and production of new IJs occur. Previous studies clearly showed benefits to the association for the nematode during the parasitic stage, but preliminary data suggest the existence of costs to the association for the nematode in free stage. IJs deprived from their bacteria indeed survive longer than symbiotic ones. Here we show that those bacteria-linked costs and benefits lead to a trade-off between fitness traits of the symbiotic nematodes. Indeed IJs mortality positively correlates with their parasitic success in the insect host for symbiotic IJs and not for aposymbiotic ones. Moreover mortality and parasitic success both positively correlate with the number of bacteria carried per IJ, indicating that the trade-off is induced by symbiosis. Finally, the trade-off intensity depends on parental effects and, more generally, is greater under restrictive environmental conditions.

  3. Bot fly parasitism of the red-backed vole: host survival, infection risk, and population growth.

    Science.gov (United States)

    Lemaître, Jérôme; Fortin, Daniel; Montiglio, Pierre-Olivier; Darveau, Marcel

    2009-03-01

    Parasites can play an important role in the dynamics of host populations, but empirical evidence remains sparse. We investigated the role of bot fly (Cuterebra spp.) parasitism in red-backed voles (Myodes gapperi) by first assessing the impacts of the parasite on the probability of vole survival under stressful conditions as well as on the reproductive activity of females. We then identified the main factors driving both the individual risk of infection and the abundance of bot flies inside red-backed voles. Finally, we evaluated the impacts of bot fly prevalence on the growth rate of vole populations between mid-July and mid-August. Thirty-six populations of red-backed voles were sampled in the boreal forest of Québec, Canada. The presence and the abundance of parasites in voles, two host life history traits (sex and body condition), three indices of habitat complexity (tree basal area, sapling basal area, coarse woody debris volume), and vole abundance were considered in models evaluating the effects of bot flies on host populations. We found that the probability of survival of red-backed voles in live traps decreased with bot fly infection. Both the individual risk of infection and the abundance of bot flies in red-backed voles were driven mainly by vole abundance rather than by the two host life history traits or the three variables of habitat complexity. Parasitism had population consequences: bot fly prevalence was linked to a decrease in short-term growth rate of vole populations over the summer. We found that bot flies have the potential to reduce survival of red-backed voles, an effect that may apply to large portions of populations.

  4. Effects of absolute fasting on reproduction and survival of the invasive apple snail Pomacea canaliculata in its native range.

    Science.gov (United States)

    Tamburi, Nicolás E; Martín, Pablo R

    2016-08-01

    A South American freshwater gastropod, the apple snail Pomacea canaliculata, has become a driver of ecosystemic changes in wetlands and an important rice pest after its introduction to various parts of the world, mainly Asia. The objective of this study was to study the effect of an abrupt interruption in food availability in the short term (up to 4 weeks) and long term (up to 8 months) on survival and reproductive activity. The main results indicate that short-term fasting mainly affects the survival of males, but only when they are raised together with females, probably due to a greater mate-searching activity that increases mortality in the individuals with lower reserves. The number of copulating snails or egg-laying females shows an abrupt drop when fasting and a rapid recovery after the food supply is restored. The strategy of discontinuing reproductive activity prioritizes energy conservation for the survival of the females. Interpopulation variation in resistance to starvation was observed in adults, which can be explained to some extent by the food availability that they experienced in their natural environment. No interpopulational differences in survival were seen in hatchlings. The mean maximum values of survival under starvation were 52.6 days in hatchlings and the 3.3% of adults survive over than 200 days, which may be a relevant trait in dispersal and establishment in new habitats.

  5. Does a trade-off between current reproductive success and survival affect the honesty of male signalling in species with male parental care?

    Science.gov (United States)

    Kelly, N B; Alonzo, S H

    2010-11-01

    Recent theory predicted that male advertisement will reliably signal investment in paternal care in species where offspring survival requires paternal care and males allocate resources between advertisement and care. However, the predicted relationship between care and advertisement depended on the marginal gains from investment in current reproductive traits. Life history theory suggests that these fitness gains are also subject to a trade-off between current and future reproduction. Here, we investigate whether male signalling remains a reliable indicator of parental care when males allocate resources between current advertisement, paternal care and survival to future reproduction. We find that advertisement is predicted to remain a reliable signal of male care but that advertisement may cease to reliably indicate male quality because low-quality males are predicted to invest in current reproduction, whereas higher-quality males are able to invest in both current reproduction and survival to future reproduction. © 2010 The Authors. Journal Compilation © 2010 European Society For Evolutionary Biology.

  6. Serum insulin-like growth factor-I (IGF-I) and growth in children born after assisted reproduction

    DEFF Research Database (Denmark)

    Kai, Claudia Mau; Main, Katharina M; Andersen, Anders Nyboe

    2006-01-01

    CONTEXT: Concern has been raised about the safety of assisted reproduction techniques for the offspring. OBJECTIVES: The objective of the study was to investigate postnatal growth and growth factors in children born after intra-cytoplasmatic sperm injection (ICSI) and in vitro fertilization (IVF...... their target height (sd score) at 3 yr of age [mean -0.91 (1.2)], compared with NC children [-0.61 (0.9), P = 0.033]. In the child cohort, target height attainment (sd score) and growth factors did not differ among the three groups. CONCLUSIONS: The overall growth pattern of ICSI and IVF children in both...... cohorts was normal. Our findings of subtle differences in target height attainment and serum IGF-I levels between infants born after assisted reproduction techniques and controls may not be clinically significant. However, these observations indicate that further systematic follow-up of growth and puberty...

  7. Reproductive ability of female dogs (beagles) surviving a single, midlethal, whole-body x-ray exposure

    International Nuclear Information System (INIS)

    Andersen, A.C.; Rosenblatt, L.S.

    1976-01-01

    The ability of 82 irradiated and sham-treated female beagles to whelp and wean pups was tested over a major portion of their reproductive life span. The dogs were exposed to 290 or 300 R of x rays (250 kVp) either as young pups, prior to puberty, or at puberty. Although all of the irradiated dogs were fertile and produced approximately the same number of litters as controls, litters of the pup irradiated and prepubertal irradiated dams surviving throughout the study were smaller than those of controls by 17 and 9 percent, respectively. Pup survival was also reduced relative to controls; the number of pups weaned was 38 percent lower in the pup irradiated group and 18 percent lower in the prepubertal irradiated group, as compared with controls. The overall reproductive ability of dogs irradiated at puberty was similar to that of sham-treated controls

  8. Survival benefits of post-fledging care: experimental approach to a critical part of avian reproductive strategies.

    Science.gov (United States)

    Grüebler, Martin U; Naef-Daenzer, Beat

    2010-03-01

    1. Caring for offspring beyond leaving the nest is an important but under-studied part of avian life histories. Theory predicts that prolonged post-fledging parental care should yield fitness benefits such as increased fledgling survival. Post-fledging care is also costly in terms of time and energy available for subsequent reproduction, moult or migration. So far, direct measurements of the fitness effects of the duration of post-fledging parental care are lacking. 2. In a partial cross-fostering experiment, barn swallow (Hirundo rustica) chicks were exchanged among broods close to fledging. Thereby, we separated the effects of post-fledging care from those of pre-fledging origin on juvenile survival. 3. Prolonging post-fledging care substantially increased juvenile survival up to 3 weeks post-fledging. Juvenile mortality was maximal in the days following the termination of parental care, and prolonging care delayed and reduced this peak mortality. Survival of fledglings experiencing 6 days of care was Phi = 0.227, whereas fledglings experiencing 14 days of care showed a survival of Phi = 0.571. 4. Offspring from pairs providing short care showed lower post-fledging survival than did offspring from pairs providing long care, irrespective of the actual duration of care experienced. This gives evidence for an additional survival effect of pre-fledging factors associated with the parental duration of care. 5. The results suggest that differential survival in relation to post-fledging parental care is a major fitness component. This relationship has profound effects on the reproductive trade-offs underlying the evolution of avian life histories.

  9. Survival rates and lifetime reproduction of breeding male Cooper’s Hawks in Wisconsin, 1980-2005

    Science.gov (United States)

    Rosenfield, Robert N.; Bielefeldt, John; Rosenfield, Laura J.; Booms, Travis L.; Bozek, Michael A.

    2009-01-01

    There are few published data on annual survival and no reports of lifetime reproduction for breeding Cooper's Hawks (Accipiter cooperii). Breeding males (n  =  105) in central and southeastern Wisconsin had an annual mortality rate of 19%, or a survival rate of 81% for birds ≤10 years of age. We did not detect significant differences in mortality rates between urban and rural habitats, nor between the earlier 13 years and later 13 years of this study. Male Cooper's Hawks produced from zero to 32 nestlings during their lifetimes. Body mass or size appeared unrelated to annual survivorship and lifetime reproduction, although lifetime reproduction was correlated strongly with longevity of breeding males. Fifteen of 66 males (23%) produced most (53%) of the nestlings. Our studies occurred in an area where breeding populations may be increasing with some of the highest reported productivity indices and nesting densities for this species. Habitat used for nesting on our Wisconsin study areas may be less important for survivorship and lifetime reproduction than acquisition of a nesting area in which a male will breed throughout his life.

  10. Effect of single and binary combinations of plant-derived molluscicides on reproduction and survival of the snail Achatina fulica.

    Science.gov (United States)

    Rao, I G; Singh, D K

    2000-11-01

    The effects of sublethal treatments (20% and 60% of LC(50)/24 h) with plant-derived molluscicides on the reproduction of the giant African snail Achatina fulica were studied. Azadirachta indica oil, Cedrus deodara oil, Allium sativum bulb powder, and Nerium indicum bark powder singly and binary combinations on reproduction and survival of A. fulica were investigated. Repeated treatment occurred on day 0, day 15, and day 30. These plant-derived molluscicides significantly reduced fecundity, egg viability, and survival of A. fulica within 15 days. Discontinuation of the treatments after day 30 did not lead to a recovery trend in the next 30 days. Day 0 sublethal treatment of all the molluscicides caused a maximum reduction in protein, amino acid, DNA, RNA, and phospholipid levels and simultaneous increase in lipid peroxidation in the ovotestis of treated A. fulica. It is believed that sublethal exposure of these molluscicides on snail reproduction is a complex process, involving more than one factor in reducing the reproductive capacity of A. fulica.

  11. Toxicity of copper nanoparticles and CuCl2 salt to Enchytraeus albidus worms: Survival, reproduction and avoidance responses

    International Nuclear Information System (INIS)

    Amorim, Mónica João Barros; Scott-Fordsmand, Janeck James

    2012-01-01

    Environmental effects of copper nanoparticles are little studied in terrestrial ecosystems. In the present article, the toxicity of copper nanoparticles (Cu-NP) on the enchytraeid Enchytraeus albidus is compared to the toxicity of a copper-salt (CuCl 2 ). The effect parameters studied were survival, reproductive output and avoidance behaviour. The results show that Cu-NP were more toxic to E. albidus than the same concentrations of the CuCl 2 -salt. The physic-chemical analysis of the particles indicated that only a small fraction was released as ions. Hence, the results indicated a nanoparticle-specific effect – lower reproductive output and higher avoidance. This was observed as 2–8 fold (significant) lower ECx values for Cu-NP (EC 50-reprod = 95 mg Cu/kg; EC 50-avoid = 241 mg Cu/kg) exposed organisms compared to CuCl 2 (EC 50-reprod = 251 mg Cu/kg; EC 50-avoid = 475 mg Cu/kg) exposed organisms. These results corroborate with a nanoparticle-specific effect. - Highlights: ► Enchytraeus albidus were exposed to Cu-salt and Cu nanoparticles (80 nm) in soil. ► Survival, reproduction and avoidance behaviour were assessed. ► Particles characterization indicated very small ion release. ► Cu nanoparticles toxicity was higher than Cu-salt for reproduction and avoidance. - Toxicity of Cu chloride salt and Cu nanoparticles to Enchytraeus albidus indicated higher toxicity of Cu-NP.

  12. Effect of commercial grade endosulfan on growth and reproduction of the fighting fish Betta splendens.

    Science.gov (United States)

    Balasubramani, A; Pandian, T J

    2014-09-01

    To study the effects of endosulfan on survival, growth and reproduction of the obligate air-breathing male heterogametic fighting fish Betta splendens, posthatchlings of the fighting fish were discretely immersed for 3 h/day during the labile period on the 2nd, 5th, and 8th day posthatching (dph) at selected concentrations of commercial grade endosulfan ranging from 175 to 1400 ng/L. The immersions at 1,400 ng/L led to 21% mortality, among the 79% of surviving fry, 80% developed into females. The endosulfan reduced the air-breathing frequency of 5- and 8-day old hatchlings, and the reduction in the frequency persisted even after a depuration period of 172 days. In the ovary of the treated females, reduced number of vitellogenic oocytes with increased vacuolar cavities was observed. In the testis of the treated males, the reduced number of spermatogonia with increased vacuolar cavities was observed. The treated male induced the female to spawn a fewer eggs, which were subsequently incubated in his smaller bubble nest. The control females attained puberty on the 138th dph and spawned 120 eggs once in every 15 days, the females, which were previously treated at 1400 ng/L, postponed puberty to the 179th dph and spawned 70 eggs once in every 32 days. During the 240-day experiment, endosulfan is found to reduce significantly the cumulative progeny production from 760 to 144, reducing significantly to 19% of the control. Copyright © 2012 Wiley Periodicals, Inc., a Wiley company.

  13. Triiodothyronine regulates cell growth and survival in renal cell cancer.

    Science.gov (United States)

    Czarnecka, Anna M; Matak, Damian; Szymanski, Lukasz; Czarnecka, Karolina H; Lewicki, Slawomir; Zdanowski, Robert; Brzezianska-Lasota, Ewa; Szczylik, Cezary

    2016-10-01

    Triiodothyronine plays an important role in the regulation of kidney cell growth, differentiation and metabolism. Patients with renal cell cancer who develop hypothyreosis during tyrosine kinase inhibitor (TKI) treatment have statistically longer survival. In this study, we developed cell based model of triiodothyronine (T3) analysis in RCC and we show the different effects of T3 on renal cell cancer (RCC) cell growth response and expression of the thyroid hormone receptor in human renal cell cancer cell lines from primary and metastatic tumors along with human kidney cancer stem cells. Wild-type thyroid hormone receptor is ubiquitously expressed in human renal cancer cell lines, but normalized against healthy renal proximal tube cell expression its level is upregulated in Caki-2, RCC6, SKRC-42, SKRC-45 cell lines. On the contrary the mRNA level in the 769-P, ACHN, HKCSC, and HEK293 cells is significantly decreased. The TRβ protein was abundant in the cytoplasm of the 786-O, Caki-2, RCC6, and SKRC-45 cells and in the nucleus of SKRC-42, ACHN, 769-P and cancer stem cells. T3 has promoting effect on the cell proliferation of HKCSC, Caki-2, ASE, ACHN, SK-RC-42, SMKT-R2, Caki-1, 786-0, and SK-RC-45 cells. Tyrosine kinase inhibitor, sunitinib, directly inhibits proliferation of RCC cells, while thyroid hormone receptor antagonist 1-850 (CAS 251310‑57-3) has less significant inhibitory impact. T3 stimulation does not abrogate inhibitory effect of sunitinib. Renal cancer tumor cells hypostimulated with T3 may be more responsive to tyrosine kinase inhibition. Moreover, some tumors may be considered as T3-independent and present aggressive phenotype with thyroid hormone receptor activated independently from the ligand. On the contrary proliferation induced by deregulated VHL and or c-Met pathways may transgress normal T3 mediated regulation of the cell cycle.

  14. Effects of dietary uranium on reproductive endpoints--fecundity, survival, reproductive success--of the fish Danio rerio.

    Science.gov (United States)

    Simon, Olivier; Mottin, Elmina; Geffroy, Benjamin; Hinton, Thomas

    2011-01-01

    Exposure to metal-contaminated water has been shown to result in a number of reproductive abnormalities in adult and larvae fish, such as failure of oocyte maturation and teratogenic effects. Recently, dietary uptake of metals by fish has been recognized as a critical route of exposure, however, the mechanisms of metal uptake and toxicity are poorly understood and in need of further investigation. The objectives of the present study are to quantify uranium (U dietary transfers from spiked artificial diets) in Danio rerio tissues and embryos, as well as establish its effect on reproduction and embryonic development. Uranium's environmental prominence is currently increasing because of new mining and milling activities. Uranium concentrations range from 0.02 µg/L in natural waters to 2 mg/L. The focus of this study was to examine the trophic transfer and effects of U following exposure modalities (dose, exposure duration 1 to 20 d). Two different isotopes were used to distinguish between chemical and radioactivity toxicity of U. Results showed that U trophic transfer was low (0.52%). Uranium tissue distributions showed that accumulation occurred in digestive organs (liver, digestive tract) following dietary exposure. High levels of U were measured in the gonads (female in particular, >20% of relative burden). High U accumulation levels in eggs indicated maternal transfer of the contaminant. Moreover, U trophic exposure led to a reduction in reproduction success as a function of U accumulated levels. High U exposure conditions strongly reduced the total number of eggs (50%) and their viability at 10 d (reduction of the clutch number, low quality of eggs). © 2010 SETAC.

  15. Effects of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) metabolites on cricket (Acheta domesticus) survival and reproductive success

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Baohong [Institute of Environmental and Human Health (TIEHH), and Department of Environmental Toxicology, Texas Tech University, Box 41163, Lubbock, TX 79409-1163 (United States); Freitag, Christina M. [Institute of Environmental and Human Health (TIEHH), and Department of Environmental Toxicology, Texas Tech University, Box 41163, Lubbock, TX 79409-1163 (United States); Canas, Jaclyn E. [Institute of Environmental and Human Health (TIEHH), and Department of Environmental Toxicology, Texas Tech University, Box 41163, Lubbock, TX 79409-1163 (United States); Cheng Qiuqiong [Institute of Environmental and Human Health (TIEHH), and Department of Environmental Toxicology, Texas Tech University, Box 41163, Lubbock, TX 79409-1163 (United States); Anderson, Todd A. [Institute of Environmental and Human Health (TIEHH), and Department of Environmental Toxicology, Texas Tech University, Box 41163, Lubbock, TX 79409-1163 (United States)]. E-mail: todd.anderson@tiehh.ttu.edu

    2006-11-15

    The effect of two major hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) metabolites, hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) and hexahydro-1,3,5-trinitroso-1,3,5-triazine (TNX), on cricket (Acheta domesticus) survival and reproduction was studied. RDX metabolites did not have adverse effects on cricket survival, growth, and egg production. However, MNX and TNX did affect egg hatching. MNX and TNX were more toxic in spiked-sand than in topical tests. TNX was more toxic to egg than MNX. Developmental stage and exposure time affected hatching. After 30 days exposure to MNX or TNX, the EC{sub 2}, EC{sub 5}, and EC{sub 95} were 47, 128, and 247 {mu}g/g for TNX, and 65, 140, and 253 {mu}g/g for MNX in topical tests. The ECs for 20, 50, and 95 were 21, 52, and 99 {mu}g/g for MNX, and 12, 48, and 97 {mu}g/g for TNX in sand. No gross abnormalities in cricket nypmhs were observed in all experiments indicating that neither TNX or MNX is teratogenic in this assay. - RDX metabolites did not have adverse effects on cricket survival, growth, and egg production, but adversely affected egg hatching.

  16. Effects of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) metabolites on cricket (Acheta domesticus) survival and reproductive success

    International Nuclear Information System (INIS)

    Zhang Baohong; Freitag, Christina M.; Canas, Jaclyn E.; Cheng Qiuqiong; Anderson, Todd A.

    2006-01-01

    The effect of two major hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) metabolites, hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) and hexahydro-1,3,5-trinitroso-1,3,5-triazine (TNX), on cricket (Acheta domesticus) survival and reproduction was studied. RDX metabolites did not have adverse effects on cricket survival, growth, and egg production. However, MNX and TNX did affect egg hatching. MNX and TNX were more toxic in spiked-sand than in topical tests. TNX was more toxic to egg than MNX. Developmental stage and exposure time affected hatching. After 30 days exposure to MNX or TNX, the EC 2 , EC 5 , and EC 95 were 47, 128, and 247 μg/g for TNX, and 65, 140, and 253 μg/g for MNX in topical tests. The ECs for 20, 50, and 95 were 21, 52, and 99 μg/g for MNX, and 12, 48, and 97 μg/g for TNX in sand. No gross abnormalities in cricket nypmhs were observed in all experiments indicating that neither TNX or MNX is teratogenic in this assay. - RDX metabolites did not have adverse effects on cricket survival, growth, and egg production, but adversely affected egg hatching

  17. Polyploidy in haloarchaea: advantages for growth and survival

    Directory of Open Access Journals (Sweden)

    Karolin eZerulla

    2014-06-01

    Full Text Available The investigated haloarchaeal species, Halobacterium salinarum, Haloferax mediterranii, and H. volcanii, have all been shown to be polyploid. They contain several replicons that have independent copy number regulation, and most have a higher copy number during exponential growth phase than stationary phase. The possible evolutionary advantages of polyploidy for haloarchaea, most of which have experimental support for at least one species, are discussed. These advantages include a low mutation rate and high resistance towards X-ray irradiation and desiccation, which depend on homologous recombination. For H. volcanii, it has been shown that gene conversion operates in the absence of selection, which leads to the equalization of genome copies. On the other hand, selective forces might lead to heterozygous cells, which have been verified in the laboratory. Additional advantages of polyploidy are survival over geological times in halite deposits as well as at extreme conditions on earth and at simulated Mars conditions. Recently, it was found that H. volcanii uses genomic DNA as genetic material and as a storage polymer for phosphate. In the absence of phosphate, H. volcanii dramatically decreases its genome copy number, thereby enabling cell multiplication, but diminishing the genetic advantages of polyploidy. Stable storage of phosphate is proposed as an alternative driving force for the emergence of DNA in early evolution. Several additional potential advantages of polyploidy are discussed that have not been addressed experimentally for haloarchaea. An outlook summarizes selected current trends and possible future developments.

  18. Antiprogestin mifepristone inhibits the growth of cancer cells of reproductive and non-reproductive origin regardless of progesterone receptor expression

    International Nuclear Information System (INIS)

    Tieszen, Chelsea R; Goyeneche, Alicia A; Brandhagen, BreeAnn N; Ortbahn, Casey T; Telleria, Carlos M

    2011-01-01

    Mifepristone (MF) has been largely used in reproductive medicine due to its capacity to modulate the progesterone receptor (PR). The study of MF has been expanded to the field of oncology; yet it remains unclear whether the expression of PR is required for MF to act as an anti-cancer agent. Our laboratory has shown that MF is a potent inhibitor of ovarian cancer cell growth. In this study we questioned whether the growth inhibitory properties of MF observed in ovarian cancer cells would translate to other cancers of reproductive and non-reproductive origin and, importantly, whether its efficacy is related to the expression of cognate PR. Dose-response experiments were conducted with cancer cell lines of the nervous system, breast, prostate, ovary, and bone. Cultures were exposed to vehicle or increasing concentrations of MF for 72 h and analysed for cell number and cell cycle traverse, and hypodiploid DNA content characteristic of apoptotic cell death. For all cell lines, expression of steroid hormone receptors upon treatment with vehicle or cytostatic doses of MF for 24 h was studied by Western blot, whereas the activity of the G1/S regulatory protein Cdk2 in both treatment groups was monitored in vitro by the capacity of Cdk2 to phosphorylate histone H1. MF growth inhibited all cancer cell lines regardless of tissue of origin and hormone responsiveness, and reduced the activity of Cdk2. Cancer cells in which MF induced G1 growth arrest were less susceptible to lethality in the presence of high concentrations of MF, when compared to cancer cells that did not accumulate in G1. While all cancer cell lines were growth inhibited by MF, only the breast cancer MCF-7 cells expressed cognate PR. Antiprogestin MF inhibits the growth of different cancer cell lines with a cytostatic effect at lower concentrations in association with a decline in the activity of the cell cycle regulatory protein Cdk2, and apoptotic lethality at higher doses in association with increased

  19. Antiprogestin mifepristone inhibits the growth of cancer cells of reproductive and non-reproductive origin regardless of progesterone receptor expression

    Directory of Open Access Journals (Sweden)

    Ortbahn Casey T

    2011-05-01

    Full Text Available Abstract Background Mifepristone (MF has been largely used in reproductive medicine due to its capacity to modulate the progesterone receptor (PR. The study of MF has been expanded to the field of oncology; yet it remains unclear whether the expression of PR is required for MF to act as an anti-cancer agent. Our laboratory has shown that MF is a potent inhibitor of ovarian cancer cell growth. In this study we questioned whether the growth inhibitory properties of MF observed in ovarian cancer cells would translate to other cancers of reproductive and non-reproductive origin and, importantly, whether its efficacy is related to the expression of cognate PR. Methods Dose-response experiments were conducted with cancer cell lines of the nervous system, breast, prostate, ovary, and bone. Cultures were exposed to vehicle or increasing concentrations of MF for 72 h and analysed for cell number and cell cycle traverse, and hypodiploid DNA content characteristic of apoptotic cell death. For all cell lines, expression of steroid hormone receptors upon treatment with vehicle or cytostatic doses of MF for 24 h was studied by Western blot, whereas the activity of the G1/S regulatory protein Cdk2 in both treatment groups was monitored in vitro by the capacity of Cdk2 to phosphorylate histone H1. Results MF growth inhibited all cancer cell lines regardless of tissue of origin and hormone responsiveness, and reduced the activity of Cdk2. Cancer cells in which MF induced G1 growth arrest were less susceptible to lethality in the presence of high concentrations of MF, when compared to cancer cells that did not accumulate in G1. While all cancer cell lines were growth inhibited by MF, only the breast cancer MCF-7 cells expressed cognate PR. Conclusions Antiprogestin MF inhibits the growth of different cancer cell lines with a cytostatic effect at lower concentrations in association with a decline in the activity of the cell cycle regulatory protein Cdk2, and

  20. Symbiotic regulation of plant growth, development and reproduction

    Science.gov (United States)

    Russell J. Rodriguez; D. Carl Freeman; E. Durant McArthur; Yong Ok Kim; Regina S. Redman

    2009-01-01

    The growth and development of rice (Oryzae sativa) seedlings was shown to be regulated epigenetically by a fungal endophyte. In contrast to un-inoculated (nonsymbiotic) plants, endophyte colonized (symbiotic) plants preferentially allocated resources into root growth until root hairs were well established. During that time symbiotic roots expanded at...

  1. Multigenerational effects of 4-methylbenzylidene camphor (4-MBC) on the survival, development and reproduction of the marine copepod Tigriopus japonicus.

    Science.gov (United States)

    Chen, Leyun; Li, Xiaolin; Hong, Haizheng; Shi, Dalin

    2018-01-01

    One of the most widely used organic UV filters, 4-methylbenzylidene camphor (4-MBC), is present at high concentrations in offshore waters. The marine copepod Tigriopus japonicus was exposed to different concentrations of 4-MBC (i.e., 0, 0.5, 1, 5 and 10μgL -1 ) for 4 consecutive generations (F0-F3) to evaluate the impact of 4-MBC on marine ecosystems. The results showed that in the F0 generation, 4-MBC caused significant lethal toxicity in T. japonicas at concentrations of 5 and 10μgL -1 and the nauplii were more sensitive to 4-MBC toxicity than the adults. However in the F1-F3 generations, 4-MBC exposure did not affect the survival rate. The hatching rate and the developmental duration from the nauplii to the copepodite (N-C) and from the nauplii to adult (N-A) decreased significantly in the F1-F2 generations and in the F2-F3 generations, respectively, even at the lowest exposure concentration (0.5μgL -1 ). In the subsequent two generations (i.e., the F4-F5 generations) of recovery exposure in clean seawater, the growth rates of the original 4-MBC exposure groups were still faster than the control in both the N-C and N-A stages, suggesting possible transgenerational genetic and/or epigenetic changes upon chronic 4-MBC exposure. The expression of the ecdysone receptor gene was up-regulated by 4-MBC, which was consistent with the decrease of the N-C/N-A duration. In addition, 4-MBC may induce oxidative stress and trigger apoptosis in T. japonicas, resulting in developmental, reproductive and even lethal toxicity. A preliminary risk assessment suggested that under environmentally realistic concentrations, 4-MBC had significant potential to pose a threat to marine crustaceans and marine ecosystems. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Growth and male reproduction improvement of non-thermal dielectric barrier discharge plasma treatment on chickens

    Science.gov (United States)

    Jiao Zhang, Jiao; Luong Huynh, Do; Chandimali, Nisansala; Kang, Tae Yoon; Kim, Nameun; Mok, Young Sun; Kwon, Taeho; Jeong, Dong Kee

    2018-05-01

    This study investigated whether plasma treatment of fertilized eggs before hatching could affect the growth and reproduction of chickens. Three point five-day-incubated fertilized eggs exposed to non-thermal dielectric barrier discharge plasma at 2.81 W of power for 2 min resulted in the highest growth in chickens. Plasma growth-promoting effect was regulated by the reactive oxygen species homeostasis and the improvement of energy metabolism via increasing serum hormones and adenosine triphosphate levels which were resulted from the regulation of genes involved in antioxidant defense, hormone biosynthesis and energetic metabolism. Interestingly, plasma-treated male chickens conspicuously grew faster than females. Further, aspects of male reproductive system (testosterone level and sperm quality) were improved by the plasma treatment but female reproduction (estradiol and progesterone levels, egg-laying rate and egg weight) had no significant changes. Unfortunately, offspring whose parents were the optimal plasma-treated chickens did not show any difference on growth characteristics and failed to inherit excellent growth features from their parents. Our results suggest a new method to improve the growth rate and male reproductive capacity in poultry but it is only effective in the plasma direct-treated generation.

  3. Vitellogenin RNAi halts ovarian growth and diverts reproductive proteins and lipids in young grasshoppers.

    Science.gov (United States)

    Tokar, Derek R; Veleta, Katherine A; Canzano, Joseph; Hahn, Daniel A; Hatle, John D

    2014-11-01

    Reduced reproduction extends lifespan of females in many animals. To test the effects of reproduction on storage of macronutrients, we block reproductive output in the lubber grasshopper by injecting RNAi against the precursor to egg-yolk protein, vitellogenin, in early adulthood. Controls were injected with either buffer or RNAi against the major storage protein in the hemolymph, hexamerin-90. Vitellogenin RNAi greatly reduced both levels of mRNA for vitellogenin and ovarian growth, in comparison to both controls. Fat body mass was increased upon vitellogenin RNAi, but concentrations of the three hexameric storage proteins from the hemolymph were not. Surprisingly, hemolymph vitellogenin levels were increased upon vitellogenin RNAi. Total reproductive protein (hemolymph vitellogenin plus ovarian vitellin) was unchanged by vitellogenin RNAi, as reproductive protein was diverted to the hemolymph. Similarly, the increased lipid storage upon vitellogenin RNAi was largely attributable to the reduction in lipid in the ovary, due to decreased ovarian growth. A BLAST search revealed that the 515 bp sequence of vitellogenin used for RNAi had three 11 bp regions identical to the vitellogenin receptor of the cockroach Leucophaea maderae. This suggests that our treatment, in addition to reducing levels of vitellogenin transcript, may have also blocked transport of vitellogenin from the hemolymph to the ovary. This would be consistent with halted ovarian growth simultaneous with high levels of vitellogenin in the hemolymph. Nonetheless, the accumulation of vitellogenin, instead of hexameric storage proteins, is inconsistent with a simple model of the trade-off between reproduction and storage. This was observed in young females; future studies will address whether investment of proteins may shift to the soma as individuals age. Overall, our results suggest that blockage of reproduction in young grasshoppers redirects lipids to storage and reproductive proteins to the hemolymph

  4. DNA alterations and effects on growth and reproduction in Daphnia magna during chronic exposure to gamma radiation over three successive generations

    International Nuclear Information System (INIS)

    Parisot, Florian; Bourdineaud, Jean-Paul; Plaire, Delphine; Adam-Guillermin, Christelle; Alonzo, Frédéric

    2015-01-01

    Highlights: • We exposed three successive generations of Daphnia magna to chronic gamma radiation. • We examined DNA alterations and effects on survival, growth and reproduction. • DNA alterations were accumulated over a generation and transmitted to the progeny. • Effects on survival and reproduction, and delay in growth increased over generations. - Abstract: This study examined chronic effects of external Cs-137 gamma radiation on Daphnia magna exposed over three successive generations (F0, F1 and F2) to environmentally relevant dose rates (ranging from 0.007 to 35.4 mGy h −1 ). Investigated endpoints included survival, growth, reproduction and DNA alterations quantified using random-amplified polymorphic DNA polymerase chain reaction (RAPD-PCR). Results demonstrated that radiation effects on survival, growth and reproduction increased in severity from generation F0 to generation F2. Mortality after 21 days at 35.4 mGy h −1 increased from 20% in F0 to 30% in F2. Growth was affected by a slight reduction in maximum length at 35.4 mGy h −1 in F0 and by reductions of 5 and 13% in growth rate, respectively, at 4.70 and 35.4 mGy h −1 in F2. Reproduction was affected by a reduction of 19% in 21 day-fecundity at 35.4 mGy h −1 in F0 and by a delay of 1.9 days in brood release as low as 0.070 mGy h −1 in F2. In parallel, DNA alterations became significant at decreasing dose rates over the course of F0 (from 4.70 mGy h −1 at hatching to 0.007 mGy h −1 after ∼21 days) and from F0 to F2 (0.070 mGy h −1 at hatching to 0.007 mGy h −1 after ∼21 days), demonstrating their rapid accumulation in F0 daphnids and their transmission to offspring generations. Transiently more efficient DNA repair leading to some recovery at the organism level was suggested in F1, with no effect on survival, a slight reduction of 12% in 21 day-fecundity at 35.4 mGy h −1 and DNA alterations significant at highest dose rates only. The study improved our understanding of

  5. Reproduction and vegetative growth in the dioecious shrub Acer barbinerve in temperate forests of Northeast China.

    Science.gov (United States)

    Wang, Juan; Zhang, Chunyu; Gadow, Klaus V; Cheng, Yanxia; Zhao, Xiuhai

    2015-06-01

    Trade-off in dioecious plant. The trade-off between reproduction, vegetative growth and maintenance is a major issue in the life history of an organism and a record of the process which is producing the largest possible number of living offspring by natural selection. Dioecious species afford an excellent opportunity for detecting such possible trade-offs in resource allocation. In this study, we selected the dioecious shrub Acer barbinerve to examine possible trade-offs between reproduction and vegetative growth in both genders at different modular levels during three successive years. Reproductive and vegetative biomass values were assessed during successive years to evaluate their intra-annual and inter-annual trade-offs. These trade-offs were examined at shoot, branch and shrub modular levels in Acer barbinerve shrubs. An intra-annual trade-off was detected at the shoot level for both genders in 2011 and 2012. Both males and females showed a negative correlation between reproduction and vegetative growth, but this was more prominent in males. For the females of the species, inter-annual trade-offs were only found at branch and shrub levels. Slightly negative correlations in females were detected between the reproduction in 2012 and the reproduction in the two previous years. The gender ratio was significantly male biased during the three successive years of our investigation. Females had higher mortality rates in the larger diameter classes, both in 2011 and 2012. This study revealed a clear trade-off between reproduction and vegetative growth in Acer barbinerve, but results varied between males and females. The degree of autonomy of the different modular levels may affect the ability to detect such trade-offs.

  6. Effect of gossypol on survival and reproduction of the zoophytophagous stinkbug Podisus nigrispinus (Dallas

    Directory of Open Access Journals (Sweden)

    Walter S. Evangelista Junior

    2011-06-01

    Full Text Available Effect of gossypol on survival and reproduction of the zoophytophagous stinkbug Podisus nigrispinus (Dallas. Gossypol is a sesquiterpene aldehyde found in cotton plants conferring resistance against herbivory. Although the effect of this sesquiterpenoid on insect pests of cotton is known, the interaction of this compound with zoophytophagous predators such as Podisus nigrispinus (Dallas (Hemiptera, Pentatomidae has not been studied so far. Thus, the objective of this study was to evaluate the effect of the purified gossypol on nymphs and adults of P. nigrispinus. Nymphs and adults of this predator were fed on Tenebrio molitor pupae and supplemented with solutions of gossypol at concentrations of 0.00, 0.05, 0.10, and 0.20% (w/v during the nymphal and adult stages or, only during the adult stage of P. nigrispinus. The nymphal stage of the predator was, on average, two days longer when suplemmented with gossypol. Emerged adults had lower fecundity and egg hatching, especially at the highest gossypol concentration (0.20% ingested during the nymphal and adult stages. However, this predator was not affected when it ingested the compound only during the adult stage. P. nigrispinus can have delayed nymphal development and lower reproductive performance when ingesting the gossypol during the nymphal and adult stages, but only at higher concentrations of gossypol than that produced by cotton plants.Efeito do gossipol na sobrevivência e reprodução do percevejo zoofitófago Podisus nigrispinus (Dallas. O gossipol é um aldeído sesquiterpeno produzido pelo algodoeiro que confere resistência contra a herbivoria. A interação deste sesquiterpeno com predadores zoofitófagos, como Podisus nigrispinus (Dallas (Hemiptera, Pentatomidae, é inexistente apesar do reconhecido efeito do gossipol sobre insetos pragas do algodoeiro. Assim, este estudo avaliou o efeito do extrato de gossipol sobre ninfas e adultos de P. nigrispinus. O predador foi alimentado com

  7. Characterizing the reproduction number of epidemics with early subexponential growth dynamics.

    Science.gov (United States)

    Chowell, Gerardo; Viboud, Cécile; Simonsen, Lone; Moghadas, Seyed M

    2016-10-01

    Early estimates of the transmission potential of emerging and re-emerging infections are increasingly used to inform public health authorities on the level of risk posed by outbreaks. Existing methods to estimate the reproduction number generally assume exponential growth in case incidence in the first few disease generations, before susceptible depletion sets in. In reality, outbreaks can display subexponential (i.e. polynomial) growth in the first few disease generations, owing to clustering in contact patterns, spatial effects, inhomogeneous mixing, reactive behaviour changes or other mechanisms. Here, we introduce the generalized growth model to characterize the early growth profile of outbreaks and estimate the effective reproduction number, with no need for explicit assumptions about the shape of epidemic growth. We demonstrate this phenomenological approach using analytical results and simulations from mechanistic models, and provide validation against a range of empirical disease datasets. Our results suggest that subexponential growth in the early phase of an epidemic is the rule rather the exception. Mechanistic simulations show that slight modifications to the classical susceptible-infectious-removed model result in subexponential growth, and in turn a rapid decline in the reproduction number within three to five disease generations. For empirical outbreaks, the generalized-growth model consistently outperforms the exponential model for a variety of directly and indirectly transmitted diseases datasets (pandemic influenza, measles, smallpox, bubonic plague, cholera, foot-and-mouth disease, HIV/AIDS and Ebola) with model estimates supporting subexponential growth dynamics. The rapid decline in effective reproduction number predicted by analytical results and observed in real and synthetic datasets within three to five disease generations contrasts with the expectation of invariant reproduction number in epidemics obeying exponential growth. The

  8. Characterizing the reproduction number of epidemics with early subexponential growth dynamics

    Science.gov (United States)

    Viboud, Cécile; Simonsen, Lone; Moghadas, Seyed M.

    2016-01-01

    Early estimates of the transmission potential of emerging and re-emerging infections are increasingly used to inform public health authorities on the level of risk posed by outbreaks. Existing methods to estimate the reproduction number generally assume exponential growth in case incidence in the first few disease generations, before susceptible depletion sets in. In reality, outbreaks can display subexponential (i.e. polynomial) growth in the first few disease generations, owing to clustering in contact patterns, spatial effects, inhomogeneous mixing, reactive behaviour changes or other mechanisms. Here, we introduce the generalized growth model to characterize the early growth profile of outbreaks and estimate the effective reproduction number, with no need for explicit assumptions about the shape of epidemic growth. We demonstrate this phenomenological approach using analytical results and simulations from mechanistic models, and provide validation against a range of empirical disease datasets. Our results suggest that subexponential growth in the early phase of an epidemic is the rule rather the exception. Mechanistic simulations show that slight modifications to the classical susceptible–infectious–removed model result in subexponential growth, and in turn a rapid decline in the reproduction number within three to five disease generations. For empirical outbreaks, the generalized-growth model consistently outperforms the exponential model for a variety of directly and indirectly transmitted diseases datasets (pandemic influenza, measles, smallpox, bubonic plague, cholera, foot-and-mouth disease, HIV/AIDS and Ebola) with model estimates supporting subexponential growth dynamics. The rapid decline in effective reproduction number predicted by analytical results and observed in real and synthetic datasets within three to five disease generations contrasts with the expectation of invariant reproduction number in epidemics obeying exponential growth. The

  9. All or nothing: Survival, reproduction and oxidative balance in Spotted Wing Drosophila (Drosophila suzukii) in response to cold.

    Science.gov (United States)

    Plantamp, Christophe; Salort, Katleen; Gibert, Patricia; Dumet, Adeline; Mialdea, Gladys; Mondy, Nathalie; Voituron, Yann

    2016-06-01

    Winter severity and overwintering capacity are key ecological factors in successful invasions, especially in ectotherms. The integration of physiological approaches into the study of invasion processes is emerging and promising. Physiological information describes the mechanisms underlying observed survival and reproductive capacities, and it can be used to predict an organism's response to environmental perturbations such as cold temperatures. We investigated the effects of various cold treatments on life history and physiological traits of an invasive pest species, Drosophila suzukii, such as survival, fertility and oxidative balance. This species, a native of temperate Asian areas, is known to survive where cold temperatures are particularly harsh and has been recently introduced into Europe and North America. We found that cold treatments had a strong impact on adult survival but no effect on female's fertility. Although only minor changes were observed after cold treatment on studied physiological traits, a strong sex-based difference was observed in both survival and physiological markers (antioxidant defences and oxidative markers). Females exhibited higher survival, reduced oxidative defences, less damage to nucleic acids, and more damage to lipids. These results suggest that D. suzukii relies on a pathway other than oxidative balance to resist cold injury. Altogether, our results provide information concerning the mechanisms of successful invasion by D. suzukii. These findings may assist in the development of population models that predict the current and future geographic ranges of this species. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Developmental exposure to a brominated flame retardant: An assessment of effects on physiology, growth, and reproduction in a songbird, the zebra finch

    International Nuclear Information System (INIS)

    Eng, Margaret L.; Williams, Tony D.; Elliott, John E.

    2013-01-01

    Mixtures of polybrominated diphenyl ethers (PBDEs) have been widely used as additive flame retardants, and BDE-99 is one of the most predominant congeners found in the environment. BDE-99 has been reported in avian samples worldwide, yet knowledge of its toxicity to birds is minimal. We assessed the short- and long-term effects of nestling exposure to environmentally relevant levels of BDE-99 in a model passerine, the zebra finch. Early exposure to BDE-99 did not affect hematocrit, oxidative stress, or thyroid hormones in either the juvenile or adult stages, and there were no effects on chick growth or survival. BDE-99 exposure caused a dose-dependent delay in timing of reproduction, but there were no other effects on reproductive success. In zebra finches, endpoints related to reproductive behavior appear to be the most sensitive to BDE-99. However, passerines overall appear to be less sensitive than birds of prey or mammals to PBDE exposure. -- Highlights: •We exposed zebra finches nestlings to BDE-99 and raised them to sexual maturity. •Found no effects on physiology, chick growth, survival, or reproductive success. •As BDE-99 dose increased, laying interval increased. •Passerine birds possibly less sensitive to BDE-99 than mammals or other bird species. -- Nestling exposure to BDE-99 affects timing of breeding in zebra finches, but overall passerines appear to be less sensitive to PBDEs than mammals or other bird species

  11. Age, growth and aspects of reproduction of the mackerel Scomber ...

    African Journals Online (AJOL)

    The age and growth of the mackerel were determined from 1742 otoliths collected from commercial catches. The time of annulus formation was established from otolith edge examinations. Two zones. one opaque and one hyaline, are laid down during a year. The distance of each annulus from the nucleus of the otolith was ...

  12. Reproductive biology and growth of the yellowbelly rockcod ...

    African Journals Online (AJOL)

    Other studies indicate that E. marginatus aggregate for spawning, and tagging work has shown that they exhibit high site fidelity. The life history of the species indicates that it is vulnerable to overexploitation. Keywords: grouper, growth, hermaphroditism, protogyny, Serranidae African Journal of Marine Science 2006, 28(1): ...

  13. Growth and development of the reproductive organs of female ...

    African Journals Online (AJOL)

    The variation in the weight of the ovary probably reflects differences in the laying pattern of individuals, and this lends itself to simulating the ovulatory cycle and consequently gaining a better understanding of the process, which would in turn aid in determining the requirement for the nutrients responsible for the growth of ...

  14. AGE GROWTH AND ASPECTS OF REPRODUCTION OF THE ...

    African Journals Online (AJOL)

    The age and growth of the mackerel were determined from 1742 otoliths collected from commerciat catches. The time of annulus formation was established from otolith edge examinations. Two lones. one opaque and one hyaline. are laid down during a year. The distance of each annulus from the nucleus of the otolith was ...

  15. Effect of porcine reproductive and respiratory syndrome virus (PRRSV) on alveolar lung macrophage survival and function

    DEFF Research Database (Denmark)

    Oleksiewicz, Martin B.; Nielsen, Jens

    1999-01-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) recently emerged as an important cause of reproductive disorders and pneumonia in domestic pigs throughout the world. Acute cytocidal replication of PRRSV in alveolar lung macrophages causes the acute pneumonia; however, it remains largely...... infection in this system. In short, in our minimal system containing only a single cell type, phagocytosis-suppressive effects of PRRSV infection were detected, that acted at the culture level by reducing the total number of alveolar lung macrophages....

  16. Latitudinal trends in the growth and reproductive seasonality of Delesseria sanguinea, Membranoptera alata, and Phycodrys rubens (Rhodophyta)

    NARCIS (Netherlands)

    Molenaar, FJ; Breeman, AM

    The seasonality of Delesseria sanguinea, Membranoptera alata, and Phycodrys rubens (Rhodophyta) was studied at Helgoland (North Sea, Germany) and Roscoff (Brittany, France). Plants were collected at bimonthly intervals, and growth and reproduction were monitored. Growth of blades was observed mainly

  17. Assisted Reproduction Causes Reduced Fetal Growth Associated with Downregulation of Paternally Expressed Imprinted Genes That Enhance Fetal Growth in Mice.

    Science.gov (United States)

    Li, Bo; Chen, Shuqiang; Tang, Na; Xiao, Xifeng; Huang, Jianlei; Jiang, Feng; Huang, Xiuying; Sun, Fangzhen; Wang, Xiaohong

    2016-02-01

    Alteration of intrauterine growth trajectory is linked to metabolic diseases in adulthood. In mammalian and, specifically, human species, pregnancies through assisted reproductive technology (ART) are associated with changes in intrauterine growth trajectory. However, it is still unclear how ART alters intrauterine growth trajectory, especially reduced fetal growth in early to midgestation. In this study, using a mouse model, it was found that ART procedures reduce fetal and placental growth at Embryonic Day 10.5. Furthermore, ART leads to decreased methylation levels at H19, KvDMR1, and Snrpn imprinting control regions in the placentae, instead of fetuses. Furthermore, in the placenta, ART downregulated a majority of parentally expressed imprinted genes, which enhance fetal growth, whereas it upregulated a majority of maternally expressed genes which repress fetal growth. Additionally, the expression of genes that regulate placental development was also affected by ART. ART also downregulated a majority of placental nutrient transporters. Disruption of genomic imprinting and abnormal expression of developmentally and functionally relevant genes in placenta may influence the placental development and function, which affect fetal growth and reprogramming. © 2016 by the Society for the Study of Reproduction, Inc.

  18. Influence of green grass-based diets on growth and reproductive performance in dairy heifers

    DEFF Research Database (Denmark)

    Habib, M. R.; Rashid, M. H.; Islam, M. A.

    2018-01-01

    The objective of this study was to monitor the changes in growth, dry matter intake, and blood profiles (nutrition and reproductive hormones) of dairy heifers in response to green grass-based diets. Twelve crossbred heifers were equally divided into group 1: rice straw and concentrate; group 2: r...

  19. Patterns of Geographic Synchrony in Growth and Reproduction of Oaks Within California and Beyond

    Science.gov (United States)

    Walter D. Koenig; Johannes M.H. Knops

    1997-01-01

    We measured patterns of spatial synchrony in growth and reproduction by oaks using direct acorn surveys, published data on acorn production, and tree-ring chronologies. The two data sets involving acorn production both indicate that acorn crops are detectably synchronous over areas of at least 500 to 1,000 km not only within individual species but among species that...

  20. Effect of Diet on Growth and Reproduction of the African Giant Snail ...

    African Journals Online (AJOL)

    Aspects of growth and reproduction were studied in a total of 360 specimens of Archachatina marginata suturalis cultured in four dietary regimes, as follows: Group A – paw-paw (Carica papaya) leaves + powdered calcium carbonate; Group B – cocoyam (Xanthosoma sagittifolium) leaves + powdered calcium carbonate; ...

  1. Nutrient allocations and metabolism in two Collembola with contrasting reproduction and growth strategies

    DEFF Research Database (Denmark)

    Larsen, Thomas; Ventura, Marc; Damgaard, Christian

    2009-01-01

    1.  Physiological mechanisms such as allocation and release of nutrients are keys to understanding an animal's adaptation to a particular habitat. This study investigated how two detrivores with contrasting life-history traits allocated carbon (C) and nitrogen (N) to growth, reproduction and meta...

  2. Effect of mid-summer haying on growth and reproduction in prairie forbs

    Science.gov (United States)

    Becky Begay; Helen M. Alexander; Erin Questad

    2011-01-01

    Mid-summer haying is a common management practice for prairies; plant species could differ in the effect of haying on subsequent growth and reproduction. We examined the effect of haying on prairie species by performing a clipping experiment. For each of seven species, sixteen plants were chosen and half were randomly assigned to a clipping treatment and half to a...

  3. Diet quality impact on growth, reproduction, and digestive activity in .i.Brachionus calyciflorus./i

    Czech Academy of Sciences Publication Activity Database

    Štrojsová, Martina; Nedoma, Jiří; Seďa, Jaromír; Vrba, Jaroslav

    2008-01-01

    Roč. 30, č. 10 (2008), s. 1123-1131 ISSN 0142-7873 R&D Projects: GA AV ČR(CZ) IAA600170602 Institutional research plan: CEZ:AV0Z60170517 Keywords : Brachionus * phosphorus limitation * growth * reproduction * phosphatase Subject RIV: EG - Zoology Impact factor: 1.707, year: 2008

  4. Growth, development, reproductive competence and adult behaviour of Spodoptera litura (Lepidoptera: Noctuidae) reared on different diets

    International Nuclear Information System (INIS)

    Seth, R.K.; Sharma, V.P.

    2002-01-01

    Spodoptera litura was reared on natural food (castor leaves, Ricinus communis) and on a several semi-synthetic diets using quasi mass rearing techniques. The effect of the different diets and rearing regimes on S. litura growth, development, reproductive competence and adult behaviour was measured. Spodoptera litura reared from a modified chickpea-based diet provided the greatest growth index and index of adequacy. These studies were conducted as a prerequisite for the evaluation of F 1 sterility technique. (author)

  5. Modeling growth performances, survival, and feed efficiency of four ...

    African Journals Online (AJOL)

    Evolution of growth rate with age was similar in the four groups, but significant differences of growth curve parameters were found among breeds and/or sexes. Estimated hatch weight was lower in C hens and higher in FT hens. Initial specific growth rates and asymptotic body weight were higher in males for all breeds.

  6. The Ewe’s Reproductive Performance, Growth Rate and Carcass Quality of Lambs Kept in a Barn vs Those Kept under an Overhead Shelter

    Directory of Open Access Journals (Sweden)

    Ewa Kuźnicka

    2013-02-01

    Full Text Available A herd of polish lowland local sheep was divided into two equal groups: the first group was kept under an overhead shelter, and the second group was kept in a warm barn. The effect of maintenance on ewe’s reproductive performance, survival as well as the growth rate of lambs, and their carcasses quality was investigated. The lack of differences in fertility and prolificacy of ewes as well as in the survival and growth rate between the groups confirmed a good adaptation of Żelaźnieńska sheep to low temperature. Harsh environmental conditions did not cause a significant decrease of the body weight growth; however, they brought in an (insignificant reduction of subcutaneous fat thickness and meatiness of the loin part of a lamb’s body. The fat content of carcasses obtained from lambs reared under the overhead shelter was significantly lower, with no differences of meat and bones contribution between the groups.

  7. Growth and reproduction respond differently to climate in three Neotropical tree species.

    Science.gov (United States)

    Alfaro-Sánchez, Raquel; Muller-Landau, Helene C; Wright, S Joseph; Camarero, J Julio

    2017-06-01

    The response of tropical forests to anthropogenic climate change is critically important to future global carbon budgets, yet remains highly uncertain. Here, we investigate how precipitation, temperature, solar radiation and dry- and wet-season lengths are related to annual tree growth, flower production, and fruit production in three moist tropical forest tree species using long-term datasets from tree rings and litter traps in central Panama. We also evaluated how growth, flower, and fruit production were interrelated. We found that growth was positively correlated with wet-season precipitation in all three species: Jacaranda copaia (r = 0.63), Tetragastris panamensis (r = 0.39) and Trichilia tuberculata (r = 0.39). Flowering and fruiting in Jacaranda were negatively related to current-year dry-season rainfall and positively related to prior-year dry-season rainfall. Flowering in Tetragastris was negatively related to current-year annual mean temperature while Trichilia showed no significant relationships of reproduction with climate. Growth was significantly related to reproduction only in Tetragastris, where it was positively related to previous year fruiting. Our results suggest that tree growth in moist tropical forest tree species is generally reduced by drought events such as those associated with strong El Niño events. In contrast, interannual variation in reproduction is not generally associated with growth and has distinct and species-specific climate responses, with positive effects of El Niño events in some species. Understanding these contrasting climate effects on tree growth and reproduction is critical to predicting changes in tropical forest dynamics and species composition under climate change.

  8. Adult survival and population growth rate in Colorado big brown bats (Eptesicus fuscus)

    Science.gov (United States)

    O'Shea, T.J.; Ellison, L.E.; Stanley, T.R.

    2011-01-01

    We studied adult survival and population growth at multiple maternity colonies of big brown bats (Eptesicus fuscus) in Fort Collins, Colorado. We investigated hypotheses about survival using information-theoretic methods and mark-recapture analyses based on passive detection of adult females tagged with passive integrated transponders. We constructed a 3-stage life-history matrix model to estimate population growth rate (??) and assessed the relative importance of adult survival and other life-history parameters to population growth through elasticity and sensitivity analysis. Annual adult survival at 5 maternity colonies monitored from 2001 to 2005 was estimated at 0.79 (95% confidence interval [95% CI] = 0.77-0.82). Adult survival varied by year and roost, with low survival during an extreme drought year, a finding with negative implications for bat populations because of the likelihood of increasing drought in western North America due to global climate change. Adult survival during winter was higher than in summer, and mean life expectancies calculated from survival estimates were lower than maximum longevity records. We modeled adult survival with recruitment parameter estimates from the same population. The study population was growing (?? = 1.096; 95% CI = 1.057-1.135). Adult survival was the most important demographic parameter for population growth. Growth clearly had the highest elasticity to adult survival, followed by juvenile survival and adult fecundity (approximately equivalent in rank). Elasticity was lowest for fecundity of yearlings. The relative importances of the various life-history parameters for population growth rate are similar to those of large mammals. ?? 2011 American Society of Mammalogists.

  9. Effects of photoperiod on boll weevil (Coleoptera: Curculionidae) development, survival, and reproduction.

    Science.gov (United States)

    Greenberg, S M; Sappington, T W; Adamczyk, J J; Liu, T-X; Setamou, M

    2008-12-01

    Effects of photoperiod on development, survival, feeding, and oviposition of boll weevils, Anthonomus grandis grandis Boheman, were assessed under five different photophases (24, 14, 12, 10, and 0 h) at a constant 27 degrees C temperature and 65% RH in the laboratory. Analyses of our results detected positive relationships between photoperiod and puncturing (mean numbers of oviposition and feeding punctures per day), and oviposition (oviposition punctures/oviposition+feeding punctures) activities, and the proportion of squares attacked by boll weevil females. When boll weevil females developed in light:darkness cycles, they produced a significantly higher percentage of eggs developing to adulthood than those developed in 24-h light or dark conditions. In long photoperiod (24:0 and 14:10 h), the number of female progeny was significantly higher and their development time was significantly shorter than those developed in short photoperiod (0:24 and 10:14 h). Lifetime oviposition was significantly highest at 12- and 14-h photophase, lowest at 0- and 10-h photophase, and intermediate at 24 h of light. Life table calculations indicated that boll weevil populations developed in a photoperiod of 14:10 and 12:12 (L:D) h will increase an average of two-fold each generation (Ro) compared with boll weevils developed in 24:0- and 10:14-h photoperiods and 15-fold compared with those at 0:24 h. Knowledge of the photoperiod-dependent population growth potential is critical for understanding population dynamics to better develop sampling protocols and timing insecticide applications.

  10. Growth and reproductive performance by different feed types in fresh water angelfish (Pterophyllum scalare Schultze, 1823

    Directory of Open Access Journals (Sweden)

    Milad Kasiri

    2012-09-01

    Full Text Available It is well established that reproduction is sensitive to the state of energy reserves, and that there is a balance between energy homeostasis and fertility. In this view, this study examined the effects of different diets on growth and reproductive performance of fresh water angelfish. Twenty four pairs of angelfish (weighing 3.58 ± 0.24 g were fed with four types of diets including live earth worm (LEW, dried Tubifex (DT, dried Gammarus (DG and prepared granulated feed (PGF, twice a day for 90 days. Reproductive parameters were measured between days 60 and 90. The significant increase in the gonadosomatic index (GSI, fecundity and hatchability brought about by the LEW were demonstrated by the higher number of spawned eggs and hatched larvae. The best growth observed significantly in PGF, and length of larvae was enhanced in this group, consequently. The numbers of dead and deformed fry were lower in the fish fed with PGF and LEW, but there was no significant difference among experimental groups. This study showed that breeders benefit from inclusion of prepared granulated feed and living earth worm during their growth and reproductive stages, and simultaneous using of them for achieving better results is suggested.

  11. Survival of egg-laying controlling neuroendocrine cells during reproductive senescence of a mollusc

    NARCIS (Netherlands)

    Janse, C.

    2004-01-01

    During brain aging neuronal degradation occurs. In some neurons this may result in degeneration and cell death, still other neurons may survive and maintain their basic properties. The present study deals with survival of the egg-laying controlling neuroendocrine caudodorsal cells (CDCs) during

  12. Effects of Pesticides on the Growth and Reproduction of Earthworm: A Review

    International Nuclear Information System (INIS)

    Yasmin, S.; Doris D'Souza, D.

    2010-01-01

    Scientific literature addressing the influence of pesticides on the growth and reproduction of earthworm is reviewed. Earthworms are considered as important bio indicators of chemical toxicity in the soil ecosystem. Studies on this aspect are important because earthworms are the common prey of many terrestrial vertebrate species such as birds and small mammals, and thus they play a key role in the bio magnification process of several soil pollutants. Majority of the studies have used mortality as an endpoint rather than subtler endpoints such as reproductive output. It is now emphasized that, whereas higher concentrations of a pollutant can easily be assessed with the acute (mortality) test, contaminated soils with lower (sublethal) pollutant concentrations require more sensitive test methods such as reproduction test in their risk assessment.

  13. Formulated feed preference for survival and optimal growth of ...

    African Journals Online (AJOL)

    Seventy-seven Bulinus snail species were fed for eight weeks with eleven diets consisting of different feed-formulations and vegetables. Snails reared exclusively on grower's mash, corn fibre meal and fish meal did not survive for up to two weeks. The result from this investigation indicatesthat there isno signiicant difference ...

  14. Human fetal growth is constrained below optimal for perinatal survival

    NARCIS (Netherlands)

    Vasak, B.; Koenen, S. V.; Koster, M. P. H.; Hukkelhoven, C. W. P. M.; Franx, A.; Hanson, M. A.; Visser, GHA

    ObjectiveThe use of fetal growth charts assumes that the optimal size at birth is at the 50(th) birth-weight centile, but interaction between maternal constraints on fetal growth and the risks associated with small and large fetal size at birth may indicate that this assumption is not valid for

  15. Studies on the growth and reproduction of cattle in the tropics

    International Nuclear Information System (INIS)

    Frisch, J.E.

    1990-01-01

    The results of a number of studies that had the long term aim of increasing the productivity of cattle in the tropics are reported. The studies were conducted on the B (Brahman), HS (interbred Hereford x Shorthorn), F 1 BX (first cross B x HS) and F n BX (interbred B x HS) lines. These breeds were used to demonstrate the origins of the heterosis that occurs in both the realized growth and the reproductive rate of Bos indicus x Bos taurus. Genetic and environmental factors that limit the realized reproductive rates were also investigated. The reproductive rate of cows of each breed that differed in lactation status during the breeding season was compared in contrasting environments. It was shown that the main limitation to HS achieving high realized reproductive rates was of environmental origin. For B cows, the main limitation was associated with the stress of lactation. Unsuccessful attempts were made to overcome this limitation by using progesterone releasing intravaginal devices alone or in combination with temporary calf weaning to try to induce a fertile oestrus. Improvement of the realized reproductive rates in the HS line was achieved by increasing their resistance to environmental stresses. The prospects for increasing the realized reproductive rate of maiden heifers by increasing their live weight at the start of their first breeding season were also investigated. About half of the heifers of each breed were implanted with the synthetic growth promotant Synovex 'H' on three occasions before the start of the breeding season. Although the live weight of all breeds increased in response to Synovex 'H', the magnitude of the response was dependent on the presence or absence of parasite control. Previously implanted heifers had a lower pregnancy rate than non-implanted heifers. 4 refs, 6 tabs

  16. Plasticity in reproduction and growth among 52 range-wide populations of a Mediterranean conifer: adaptive responses to environmental stress.

    Science.gov (United States)

    Santos-Del-Blanco, L; Bonser, S P; Valladares, F; Chambel, M R; Climent, J

    2013-09-01

    A plastic response towards enhanced reproduction is expected in stressful environments, but it is assumed to trade off against vegetative growth and efficiency in the use of available resources deployed in reproduction [reproductive efficiency (RE)]. Evidence supporting this expectation is scarce for plants, particularly for long-lived species. Forest trees such as Mediterranean pines provide ideal models to study the adaptive value of allocation to reproduction vs. vegetative growth given their among-population differentiation for adaptive traits and their remarkable capacity to cope with dry and low-fertility environments. We studied 52 range-wide Pinus halepensis populations planted into two environmentally contrasting sites during their initial reproductive stage. We investigated the effect of site, population and their interaction on vegetative growth, threshold size for female reproduction, reproductive-vegetative size relationships and RE. We quantified correlations among traits and environmental variables to identify allocation trade-offs and ecotypic trends. Genetic variation for plasticity was high for vegetative growth, whereas it was nonsignificant for reproduction. Size-corrected reproduction was enhanced in the more stressful site supporting the expectation for adverse conditions to elicit plastic responses in reproductive allometry. However, RE was unrelated with early reproductive investment. Our results followed theoretical predictions and support that phenotypic plasticity for reproduction is adaptive under stressful environments. Considering expectations of increased drought in the Mediterranean, we hypothesize that phenotypic plasticity together with natural selection on reproductive traits will play a relevant role in the future adaptation of forest tree species. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

  17. Viruses' life history: towards a mechanistic basis of a trade-off between survival and reproduction among phages.

    Directory of Open Access Journals (Sweden)

    Marianne De Paepe

    2006-07-01

    Full Text Available Life history theory accounts for variations in many traits involved in the reproduction and survival of living organisms, by determining the constraints leading to trade-offs among these different traits. The main life history traits of phages-viruses that infect bacteria-are the multiplication rate in the host, the survivorship of virions in the external environment, and their mode of transmission. By comparing life history traits of 16 phages infecting the bacteria Escherichia coli, we show that their mortality rate is constant with time and positively [corrected] correlated to their multiplication rate in the bacterial host. Even though these viruses do not age, this result is in line with the trade-off between survival and reproduction previously observed in numerous aging organisms. Furthermore, a multiple regression shows that the combined effects of two physical parameters, namely, the capsid thickness and the density of the packaged genome, account for 82% of the variation in the mortality rate. The correlations between life history traits and physical characteristics of virions may provide a mechanistic explanation of this trade-off. The fact that this trade-off is present in this very simple biological situation suggests that it might be a fundamental property of evolving entities produced under constraints. Moreover, such a positive correlation between mortality and multiplication reveals an underexplored trade-off in host-parasite interactions.

  18. Assessing single and joint effects of chemicals on the survival and reproduction of Folsomia candida (Collembola) in soil

    International Nuclear Information System (INIS)

    Amorim, M.J.B.; Pereira, C.; Menezes-Oliveira, V.B.; Campos, B.; Soares, A.M.V.M.; Loureiro, S.

    2012-01-01

    Chemicals are often found in the environment as complex mixtures. There has been a large effort in the last decade to assess the combined effect of chemicals, using the conceptual models of Concentration Addition and Independent Action, but also including synergistic, antagonistic, dose-level and dose–ratio dependent deviations from these models. In the present study, single and mixture toxicity of atrazine, dimethoate, lindane, zinc and cadmium were studied in Folsomia candida, assessing survival and reproduction. Different response patterns were observed for the different endpoints and synergistic patterns were observed when pesticides were present. Compared with the previously tested Enchytraeus albidus and Porcellionides pruinosus, the mixture toxicity pattern for F. candida was species specific. The present study highlights the importance of studying toxicity of chemicals mixtures due to the observed potentiation of effects and confirms that for an adequate ecologically relevant risk assessment different organisms and endpoints should be included. - Highlights: ► Folsomia candida (Collembola) were exposed to binary mixtures of atrazine, dimethoate, lindane, zinc and cadmium. ► Synergistic response patterns were often observed when pesticides were present in the mixtures. ► Response patterns upon mixture exposure differed within endpoints (survival vs. reproduction) in some cases. ► As to single chemical toxicity, response patterns for mixture exposures seem to be also species specific. - Exposure to chemical mixtures in Folsomia candida showed potentiation of effects. Mixture toxicity patterns differ among species and endpoint measured.

  19. Effects of Elevated Ambient Temperature on Reproductive Outcomes and Offspring Growth Depend on Exposure Time

    Directory of Open Access Journals (Sweden)

    Huda Yahia Hamid

    2012-01-01

    Full Text Available Reproductive performance has been shown to be greatly affected by changes in environmental factors, such as temperature. However, it is also crucial to identify the particular stage of pregnancy that is most adversely affected by elevated ambient temperature. The aims of this study were to determine the effect on reproductive outcomes of exposure to elevated ambient temperature during different stages of pregnancy and to determine the effect of prenatal heat stress on offspring growth. Sixty pregnant rats were used in this study. The rats were divided equally into four groups as group 1 (control, group 2 (exposed to elevated temperature following implantation, group 3 (exposed to elevated temperature during pre- and periimplantation, and group 4 (exposed to elevated temperature during pre- and periimplantation and following implantation. Groups 3 and 4 had prolonged gestation periods, reduced litter sizes, and male-biased sex ratios. Moreover, the growth patterns of group 3 and 4 pups were adversely affected by prenatal exposure to elevated temperature. The differences between group 1 and group 3 and between group 1 and group 4 were highly significant. However, no significant differences were observed between groups 1 and 2 in the gestation length, sex ratios, and growth patterns. Thus, it can be concluded that exposure to elevated ambient temperature during pre- and periimplantation has stronger adverse effects on reproductive outcomes and offspring growth than postimplantation exposure.

  20. Human disturbance influences reproductive success and growth rate in California sea lions (Zalophus californianus.

    Directory of Open Access Journals (Sweden)

    Susannah S French

    Full Text Available The environment is currently undergoing changes at both global (e.g., climate change and local (e.g., tourism, pollution, habitat modification scales that have the capacity to affect the viability of animal and plant populations. Many of these changes, such as human disturbance, have an anthropogenic origin and therefore may be mitigated by management action. To do so requires an understanding of the impact of human activities and changing environmental conditions on population dynamics. We investigated the influence of human activity on important life history parameters (reproductive rate, and body condition, and growth rate of neonate pups for California sea lions (Zalophus californianus in the Gulf of California, Mexico. Increased human presence was associated with lower reproductive rates, which translated into reduced long-term population growth rates and suggested that human activities are a disturbance that could lead to population declines. We also observed higher body growth rates in pups with increased exposure to humans. Increased growth rates in pups may reflect a density dependent response to declining reproductive rates (e.g., decreased competition for resources. Our results highlight the potentially complex changes in life history parameters that may result from human disturbance, and their implication for population dynamics. We recommend careful monitoring of human activities in the Gulf of California and emphasize the importance of management strategies that explicitly consider the potential impact of human activities such as ecotourism on vertebrate populations.

  1. Effects of light quality on reproduction, growth and pigment content of Gracilaria birdiae (Rhodophyta: Gracilariales

    Directory of Open Access Journals (Sweden)

    José Bonomi Barufi

    2015-03-01

    Full Text Available Gracilaria species are the main source of agar worldwide. Since laboratory cultivation is an important means of sustaining such production, this study aimed to assess the influence of two fundamental strategies of physiological algae adjustment, photoacclimation and photomorphogenesis, on G. birdiae physiology. Specifically, the effects of different spectral light qualities on reproduction, growth, and pigment content in two distinct photoperiods (8 and 14 hours were examined. Tetrasporophytes and gametophytes were submitted to different light qualities: white, green, red, and blue over the course of nine weeks. At the end of this period, chlorophyll a, allophycocyanin, phycocyanin, and phycoerythrin contents were analysed. Gametophytes showed reproductive structures only under monochromatic radiation. A stimulatory effect on tetrasporangium differentiation was mainly observed under red light, but this high fertility was negatively correlated with growth rate, i.e. algae cultivated under red light showed the lowest growth rate. However, while growth rates were higher in algae exposed to white light, they were similar to those observed in algae subjected to green light and 14 hours of daylight. PE was the predominant pigment, irrespective of light quality. Phycocyanin and phycoerythrin concentration increased when algae were cultivated under green and blue light. Therefore, considering future management prospects for G. birdiae mariculture, we suggest that red light could be utilized as a reproductive inductor to produce tetraspores. Furthermore, if the aim is to achieve high phycoerythrin content, continuous blue light could be applied during a short photoperiod. Indeed, the combination of different wavelengths could allow better economic resource exploitation.

  2. Radiation cell survival and growth delay studies in multicellular spheroids of small-cell lung carcinoma

    International Nuclear Information System (INIS)

    Duchesne, G.M.; Peacock, J.H.

    1987-01-01

    The radiation sensitivity of two small-cell lung carcinoma cell lines growing as multicellular spheroids in static culture was determined using clonogenic cell survival and growth delay as endpoints. Growth delay determination suggested that clonogenic cell kill was less than was obtained by direct assay of cell survival. Recovery from potentially lethal damage was assayed in one line (HC12) but was not demonstrable, and clonogenic cell survival decreased with time in treated spheroids with diameters greater than 300 μm which contained a hypoxic cell population. Microscopic examination of the treated spheroids showed the emergence of an abnormal giant-cell population, and the progressive clonogenic cell loss that occurred after treatment was thought to be due to oxygen and nutrient deprivation of the remaining viable cells by this doomed cell population. Correction of the growth delay measurements for changes in cell size and clonogenic cell population allowed correlation of the growth delay and cell survival data. (author)

  3. Five year growth and survival of Eucalyptus hybrid clones in coastal ...

    African Journals Online (AJOL)

    -urophylla i.e. GU hybrids) and three local landraces (E. camaldulensis, E. tereticornis and E. urophylla) were established in Gede, Sokoke and Msambweni in the Coast province of Kenya in 2002, to compare growth, survival and adaptability ...

  4. Does bedding promote pine survival and growth on ditched wet sands?

    Science.gov (United States)

    Ralph A. Klawitter

    1970-01-01

    Results from a study of prepared beds for planting slash pine on a wet sandy flat in Florida were inconclusive. Early growth was improved, but survival was not; and differences between a bedded site and an unbedded site were slight.

  5. Survival and Growth of Cottonwood Clones After Angle Planting and Base Angle Treatments

    Science.gov (United States)

    W.K. Randall; Harvey E. Kennedy

    1976-01-01

    Presently, commercial cottonwood plantations in the lower Mississippi Valley are established using vertically planted, unrooted cuttings with a flat (90°) base. Neither survival nor first-year growth of a group of six Stoneville clones was improved by angle planting or cutting base angles diagonally. For one clone, survival was significantly better when base angle was...

  6. High levels of maternally transferred mercury do not affect reproductive output or embryonic survival of northern watersnakes (Nerodia sipedon).

    Science.gov (United States)

    Chin, Stephanie Y; Willson, John D; Cristol, Daniel A; Drewett, David V V; Hopkins, William A

    2013-03-01

    Maternal transfer is an important exposure pathway for contaminants because it can directly influence offspring development. Few studies have examined maternal transfer of contaminants, such as mercury (Hg), in snakes, despite their abundance and high trophic position in many ecosystems where Hg is prevalent. The objectives of the present study were to determine if Hg is maternally transferred in northern watersnakes (Nerodia sipedon) and to evaluate the effects of maternal Hg on reproduction. The authors captured gravid female watersnakes (n = 31) along the South River in Waynesboro, Virginia, USA, where an extensive Hg-contamination gradient exists. The authors measured maternal tissue and litter Hg concentrations and, following birth, assessed (1) reproductive parameters (i.e., litter size and mass, neonate mass); (2) rates of infertility, death during development, stillbirths, malformations, and runts; and (3) the overall viability of offspring. Mercury concentrations in females were strongly and positively correlated with concentrations in litters, suggesting that N. sipedon maternally transfer Hg in proportion to their tissue residues. Maternal transfer resulted in high concentrations (up to 10.10 mg/kg dry wt total Hg) of Hg in offspring. The authors found little evidence of adverse effects of Hg on these measures of reproductive output and embryonic survival, suggesting that N. sipedon may be more tolerant of Hg than other vertebrate species. Given that this is the first study to examine the effects of maternally transferred contaminants in snakes and that the authors did not measure all reproductive endpoints, further research is needed to better understand factors that influence maternal transfer and associated sublethal effects on offspring. Copyright © 2013 SETAC.

  7. Epidermal growth factor receptor: an independent predictor of survival in astrocytic tumors given definitive irradiation

    International Nuclear Information System (INIS)

    An Zhu; Shaeffer, James; Leslie, Susan; Kolm, Paul; El-Mahdi, Anas M.

    1996-01-01

    Purpose: To determine whether the expression of epidermal growth factor receptor (EGFR) protein was predictive of patient survival independently of other prognostic factors in astrocytic tumors. Methods and Materials: Epidermal growth factor receptor protein expression was investigated immunohistochemically in formalin-fixed, paraffin-embedded surgical specimens of 55 glioblastoma multiforme, 14 anaplastic astrocytoma, and 2 astrocytomas given definitive irradiation. We evaluated the relationship of EGFR protein expression and tumor grade, histologic features, age at diagnosis, sex, patient survival, and recurrence-free survival. Results: The percentage of tumor cells which were EGFR positive related to reduced survival by Cox regression analysis in both univariate (p = 0.0424) and multivariate analysis (p = 0.0016). Epidermal growth factor receptor positivity was the only 1 of 11 clinical and histological variables associated with decreased recurrence-free survival by either univariate (p = 0.0353) or multivariate (p = 0.0182) analysis. Epidermal growth factor receptor protein expression was not related to patient age, sex, or histologic features. Conclusion: Epidermal growth factor receptor positivity was a significant and independent prognostic indicator for overall survival and recurrence-free survival for irradiated patients with astrocytic gliomas

  8. Survival and growth of fresh and stored planting stock.

    Science.gov (United States)

    Robert H. Ruth

    1953-01-01

    Does planting stock that has been kept in storage survive and grow as well as freshly dug stock? This question is important because the ground at a forest nursery may still be frozen when spring planting time arrives in the warmer parts of the region. This means that seedlings for spring planting need to be dug in the fall, kept in cold storage over winter, and shipped...

  9. Effects of depleted uranium on the reproductive success and F1 generation survival of zebrafish (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Bourrachot, Stéphanie [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Brion, François [Institut National de l’Environnement Industriel et des Risques (INERIS), Unité d’évaluation des risques écotoxicologiques, BP2, 60550 Verneuil-en-Halatte (France); Pereira, Sandrine; Floriani, Magali; Camilleri, Virginie; Cavalié, Isabelle [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France); Palluel, Olivier [Institut National de l’Environnement Industriel et des Risques (INERIS), Unité d’évaluation des risques écotoxicologiques, BP2, 60550 Verneuil-en-Halatte (France); Adam-Guillermin, Christelle, E-mail: christelle.adam-guillermin@irsn.fr [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, Saint-Paul-lez-Durance 13115 (France)

    2014-09-15

    Highlights: • The effect of depleted uranium on zebrafish reproduction was studied. • An inhibition of egg production and an increase of F1 embryo mortality were observed. • Decreased circulating concentration of vitellogenin was observed in females. • Increased DNA damages were observed in parent gonads and in embryos. • U environmental concentration impairs reproduction and genetic integrity of fish. - Abstract: Despite the well-characterized occurrence of uranium (U) in the aquatic environment, very little is known about the chronic exposure of fish to low levels of U and its potential effect on reproduction. Therefore, this study was undertaken to investigate the effects of environmental concentrations of depleted U on the reproductive output of zebrafish (Danio rerio) and on survival and development of the F1 embryo-larvae following parental exposure to U. For that purpose, sexually mature male and female zebrafish were exposed to 20 and 250 μg/L of U for 14 days and allowed to reproduce in clean water during a further 14-day period. At all sampling times, whole-body vitellogenin concentrations and gonad histology were analyzed to investigate the effects of U exposure on these reproductive endpoints. In addition, accumulation of U in the gonads and its genotoxic effect on male and female gonad cells were quantified. The results showed that U strongly affected the capability of fish to reproduce and to generate viable individuals as evidenced by the inhibition of egg production and the increased rate of mortality of the F1 embryos. Interestingly, U exposure resulted in decreased circulating concentrations of vitellogenin in females. Increased concentrations of U were observed in gonads and eggs, which were most likely responsible for the genotoxic effects seen in fish gonads and in embryos exposed maternally to U. Altogether, these findings highlight the negative effect of environmentally relevant concentrations of U which alter the reproductive

  10. Effects of depleted uranium on the reproductive success and F1 generation survival of zebrafish (Danio rerio)

    International Nuclear Information System (INIS)

    Bourrachot, Stéphanie; Brion, François; Pereira, Sandrine; Floriani, Magali; Camilleri, Virginie; Cavalié, Isabelle; Palluel, Olivier; Adam-Guillermin, Christelle

    2014-01-01

    Highlights: • The effect of depleted uranium on zebrafish reproduction was studied. • An inhibition of egg production and an increase of F1 embryo mortality were observed. • Decreased circulating concentration of vitellogenin was observed in females. • Increased DNA damages were observed in parent gonads and in embryos. • U environmental concentration impairs reproduction and genetic integrity of fish. - Abstract: Despite the well-characterized occurrence of uranium (U) in the aquatic environment, very little is known about the chronic exposure of fish to low levels of U and its potential effect on reproduction. Therefore, this study was undertaken to investigate the effects of environmental concentrations of depleted U on the reproductive output of zebrafish (Danio rerio) and on survival and development of the F1 embryo-larvae following parental exposure to U. For that purpose, sexually mature male and female zebrafish were exposed to 20 and 250 μg/L of U for 14 days and allowed to reproduce in clean water during a further 14-day period. At all sampling times, whole-body vitellogenin concentrations and gonad histology were analyzed to investigate the effects of U exposure on these reproductive endpoints. In addition, accumulation of U in the gonads and its genotoxic effect on male and female gonad cells were quantified. The results showed that U strongly affected the capability of fish to reproduce and to generate viable individuals as evidenced by the inhibition of egg production and the increased rate of mortality of the F1 embryos. Interestingly, U exposure resulted in decreased circulating concentrations of vitellogenin in females. Increased concentrations of U were observed in gonads and eggs, which were most likely responsible for the genotoxic effects seen in fish gonads and in embryos exposed maternally to U. Altogether, these findings highlight the negative effect of environmentally relevant concentrations of U which alter the reproductive

  11. Combined effects of extremely high frequency electromagnetic field and antibiotics on Enterococcus Hirae growth and survival

    International Nuclear Information System (INIS)

    Ohanyan, V.A.

    2012-01-01

    Combined effects of extremely high frequency electromagnetic field and antibiotics on Enterococcus hirae ATCC 9790 bacterial growth and survival were investigated using 51.8 GHz and 53 GHz frequencies in combination with two commonly used antibiotics: ampicillin and dalacin. Results revealed that, despite bacterial type and membrane structure and properties, the combined effect, especially with 53 GHz and dalacin, suppresses bacterial growth and decreases their survival

  12. Effect of gamma rays on growth and survival of three mustard varieties in M1 generation

    International Nuclear Information System (INIS)

    Kamala, T.; Rao, R.N.B.

    1982-01-01

    Effects of gamma radiation on germination, survival percentage, seedling height, leaf length and breadth, and growth rate in three mustard varieties were studied in M 1 generation. Seeds were exposed to 15, 30, 45, 60 and 80 Kr doses for the study. Germinations and survival percentages and seedling height showed dose-dependent decrease, while growth rate, leaf length and breadth increased at 60, 45 and 30 Kr and decreased at 80 Kr, though varietal differences were observed. (M.G.B.)

  13. Effects of high dose rate gamma radiation on survival and reproduction of Biomphalaria glabrata

    International Nuclear Information System (INIS)

    Cantinha, Rebeca S.; Nakano, Eliana; Silva, Luanna R.S.

    2009-01-01

    Ionizing radiations are known as mutagenic agents, causing lethality and infertility. This characteristic has motivated its application on animal biological control. In this context, the freshwater snail Biomphalaria glabrata can be considered an excellent experimental model to study effects of ionizing radiations on lethality and reproduction. This work was designed to evaluate effects of 60 Co gamma radiation at high dose rate (10.04 kGy/h) on B. glabrata. For this purpose, adult snails were selected and exposed to doses ranging from 20 to 100 Gy, with 10 Gy intervals; one group was kept as control. There was not effect of dose rate in the lethality of gamma radiation; the value of 64,3 Gy of LD 50 obtained in our study was similar to that obtained by other authors with low dose rates. Nevertheless, our data suggest that there was a dose rate effect in the reproduction. On all dose levels, radiation improved the production of embryos for all exposed individuals. However, viability indexes were below 6% and, even 65 days after irradiation, fertility was not recovered. These results are not in agreement with other studies using low dose rates. Lethality was obtained in all groups irradiated, and the highest doses presented percentiles of dead animals above 50%. The results demonstrated that doses of 20 and 30 Gy were ideal for population control of B. glabrata. Further studies are needed; nevertheless, this research evidenced great potential of high dose rate gamma radiation on B. glabrata reproductive control. (author)

  14. Effects of high dose rate gamma radiation on survival and reproduction of Biomphalaria glabrata

    Energy Technology Data Exchange (ETDEWEB)

    Cantinha, Rebeca S.; Nakano, Eliana [Instituto Butantan, Sao Paulo, SP (Brazil). Lab. de Parasitologia], e-mail: rebecanuclear@gmail.com, e-mail: eliananakano@butantan.gov.br; Borrely, Sueli I. [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Sao Paulo, SP (Brazil). Centro de Tecnologia das Radiacoes], e-mail: sborrely@ipen.br; Amaral, Ademir; Melo, Ana M.M.A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia (GERAR)], e-mail: amaral@ufpe.br; Silva, Luanna R.S. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Biofisica e Radiobiologia. Lab. de Radiobiologia], e-mail: amdemelo@hotmail.com, e-mail: luannaribeiro_lua@hotmail.com

    2009-07-01

    Ionizing radiations are known as mutagenic agents, causing lethality and infertility. This characteristic has motivated its application on animal biological control. In this context, the freshwater snail Biomphalaria glabrata can be considered an excellent experimental model to study effects of ionizing radiations on lethality and reproduction. This work was designed to evaluate effects of {sup 60}Co gamma radiation at high dose rate (10.04 kGy/h) on B. glabrata. For this purpose, adult snails were selected and exposed to doses ranging from 20 to 100 Gy, with 10 Gy intervals; one group was kept as control. There was not effect of dose rate in the lethality of gamma radiation; the value of 64,3 Gy of LD{sub 50} obtained in our study was similar to that obtained by other authors with low dose rates. Nevertheless, our data suggest that there was a dose rate effect in the reproduction. On all dose levels, radiation improved the production of embryos for all exposed individuals. However, viability indexes were below 6% and, even 65 days after irradiation, fertility was not recovered. These results are not in agreement with other studies using low dose rates. Lethality was obtained in all groups irradiated, and the highest doses presented percentiles of dead animals above 50%. The results demonstrated that doses of 20 and 30 Gy were ideal for population control of B. glabrata. Further studies are needed; nevertheless, this research evidenced great potential of high dose rate gamma radiation on B. glabrata reproductive control. (author)

  15. The Influence of Thermic Plastic Films on Vegetative and Reproductive Growth of Iceberg Lettuce 'Dublin'

    OpenAIRE

    Wael M. Semida; P. Hadley; W. Sobeih; N. A. El-Sawah; M. A. S. Barakat

    2013-01-01

    Photoselective plastic films with thermic properties are now available so that greenhouses clad with such plastics exhibit a higher degree of “Greenhouse Effect” with a consequent increase in night time temperature. In this study, we investigate the potential benefits of a range of thermic plastic films used as greenhouse cover materials on the vegetative and reproductive growth and development of Iceberg lettuce (Lactuca sativa L). Transplants were grown under thermic fi...

  16. Assessment of reproductive and growth performances of pig breeds in the peri-urban area of Douala (Equatorial Zone

    Directory of Open Access Journals (Sweden)

    J. Kouamo

    2015-06-01

    Full Text Available The aim of this study was to evaluate the reproductive and growth performances of pig breeds in Douala, Cameroon. The reproductive performance of gilts and multiparous sows (38 per group from 8 selected farms were monitored and controlled. Thereafter, piglets were controlled from birth to weaning age. The age at first service (AFS, fertility index (FI, fecundity, age at first farrowing (AFF, weight at first farrowing (WtFF and litter size (LS of gilts were 179.97 ± 25.40 days; 1.76 ± 0.77; 100 ± 0.00; 350.47 ± 40.58 days; 107.26 ± 31.85 kg and 7.18 ± 1.93 piglets, respectively. In sows, the FI, fecundity, LS and farrowing interval (FarI were 1.13 ± 0.34; 100 ± 0.00; 9.03 ± 2.14 piglets and 179.63 ± 25.14 days, respectively. FI and LS were better in sows compared to gilts (P = 0.000. The sex ratio was 0.63. Local breed animals reared in semi-modern farms and fed mixed feed showed the lowest WtFF. In piglets, the average birth weight (kg, the average weaning weight (kg, age at weaning (days and survival rate (% until weaning were 1.32 ± 0.20, 10.60 ± 1.41, 56.86 ± 8.24 and 48.43, respectively. These results indicated that reproductive performance is strongly influenced by breed, feed and farm type.

  17. Sex-specific impact of prenatal stress on growth and reproductive parameters of guinea pigs.

    Science.gov (United States)

    Schöpper, Hanna; Klaus, Teresa; Palme, Rupert; Ruf, Thomas; Huber, Susanne

    2012-12-01

    Body condition and reproductive maturation are parameters of reproductive success that are influenced by sexual hormones rising in the circulation during the time of puberty. Various endocrine systems can be programmed by conditions experienced during early life. Stress for instance is supposed to be capable of influencing fetal development, leading to adjustments of offspring's later physiology. We examined whether prenatal stress (induced by exposure to strobe light) during early- to mid-gestation was capable of affecting later reproductive parameters in guinea pigs (Cavia aperea f. porcellus). Therefore, we measured the levels of testosterone and progesterone from the age of day 12-124 in prenatally stressed (PS, n = 20) and unaffected control animals (n = 24). Furthermore, we determined the timing of puberty and growth. Body weight development revealed significantly faster growth in PS females compared to control animals. The onset of first estrus was slightly earlier in PS females, however not significantly so. Cycle lengths and levels of progesterone differed between groups over the course of time with higher progesterone levels and more constant cycles among PS females compared to control females who displayed marked differences between first and subsequent cycles. Levels of testosterone did not differ between groups. We conclude that prenatal stress accelerates growth and maturity in females, but not in males.

  18. Plant circadian clocks increase photosynthesis, growth, survival, and competitive advantage.

    Science.gov (United States)

    Dodd, Antony N; Salathia, Neeraj; Hall, Anthony; Kévei, Eva; Tóth, Réka; Nagy, Ferenc; Hibberd, Julian M; Millar, Andrew J; Webb, Alex A R

    2005-07-22

    Circadian clocks are believed to confer an advantage to plants, but the nature of that advantage has been unknown. We show that a substantial photosynthetic advantage is conferred by correct matching of the circadian clock period with that of the external light-dark cycle. In wild type and in long- and short-circadian period mutants of Arabidopsis thaliana, plants with a clock period matched to the environment contain more chlorophyll, fix more carbon, grow faster, and survive better than plants with circadian periods differing from their environment. This explains why plants gain advantage from circadian control.

  19. Periodic matrix population models: growth rate, basic reproduction number, and entropy.

    Science.gov (United States)

    Bacaër, Nicolas

    2009-10-01

    This article considers three different aspects of periodic matrix population models. First, a formula for the sensitivity analysis of the growth rate lambda is obtained that is simpler than the one obtained by Caswell and Trevisan. Secondly, the formula for the basic reproduction number R0 in a constant environment is generalized to the case of a periodic environment. Some inequalities between lambda and R0 proved by Cushing and Zhou are also generalized to the periodic case. Finally, we add some remarks on Demetrius' notion of evolutionary entropy H and its relationship to the growth rate lambda in the periodic case.

  20. Low light availability affects leaf gas exchange, growth and survival ...

    African Journals Online (AJOL)

    The values of dark respiration rate (Rd) and photosynthetic compensation irradiance (Ic) were sufficiently low for a positive carbon balance. Notwithstanding, the interpretation of results of microclimate variables together with leaf gas exchange and growth variables indicated that seedlings at all sites were in a suboptimal ...

  1. Growth and Survival of Catfish ( Clarias anguillaris ) Juveniles Fed ...

    African Journals Online (AJOL)

    Juveniles of catfish, Clarias anguillaris (mean weight, 119.8g) were fed unconventional diets for ten weeks in outdoor hapas (net cages, 1m3 dimension) and the growth responses and feed utilization by the juveniles were compared. The experimental diets were (i) live maggots, (ii) live tilapia fry, (iii) commercial catfish feed ...

  2. Survival of Salmonella on chamomile, peppermint, and green tea during storage and subsequent survival or growth following tea brewing.

    Science.gov (United States)

    Keller, Susanne E; Stam, Christina N; Gradl, Dana R; Chen, Zhengzai; Larkin, Emily L; Pickens, Shannon R; Chirtel, Stuart J

    2015-04-01

    The survival of Salmonella on dried chamomile flowers, peppermint leaves, and green tea leaves stored under different conditions was examined. Survival and growth of Salmonella was also assessed after subsequent brewing using dried inoculated teas. A Salmonella enterica serovar cocktail was inoculated onto different dried tea leaves or flowers to give starting populations of approximately 10 log CFU/g. The inoculum was allowed to dry (at ambient temperature for 24 h) onto the dried leaves or flowers prior to storage under 25 and 35 °C at low (90% RH) humidity levels. Under the four storage conditions tested, survival followed the order 25 °C with low RH > 35 °C with low RH > 25 °C with high RH > 35 °C with high RH. Salmonella losses at 25 °C with low RH occurred primarily during drying, after which populations showed little decline over 6 months. In contrast, Salmonella decreased below detection after 45 days at 35 °C and high RH in all teas tested. The thermal resistance of Salmonella was assessed at 55 °C immediately after inoculation of tea leaves or flowers, after drying (24 h) onto tea leaves or flowers, and after 28 days of storage at 25 °C with low RH. All conditions resulted in similar D-values (2.78 ± 0.12, 3.04 ± 0.07, and 2.78 ± 0.56, at 0 h, 24 h, and 28 days, respectively), indicating thermal resistance of Salmonella in brewed tea did not change after desiccation and 28 days of storage. In addition, all brewed teas tested supported the growth of Salmonella. If Salmonella survives after storage, it may also survive and grow after a home brewing process.

  3. Effects of engineered nanoparticles on survival, reproduction, and behaviour of freshwater snail, Physa acuta (Draparnaud, 1805)

    CSIR Research Space (South Africa)

    Musee, N

    2010-01-01

    Full Text Available -alumina, modified TiO2 (M-TiO2), and commercial TiO2 (C-TiO2) ENPs on the survival, behaviour, and early life stages of the freshwater snail Physa acuta (Draparnaud). The toxicity evaluation was carried out after spiking commercial sand with ENPs concentrations of 0...

  4. Changes in oxidative stress parameters in relation to age, growth and reproduction in the short-lived catarina scallop Argopecten ventricosus reared in its natural environment.

    Science.gov (United States)

    Guerra, C; Zenteno-Savín, T; Maeda-Martínez, A N; Philipp, E E R; Abele, D

    2012-08-01

    Increase in oxidative damage and decrease in cellular maintenance is often associated with aging, but, in marine ectotherms, both processes are also strongly influenced by somatic growth, maturation and reproduction. In this study, we used a single cohort of the short-lived catarina scallop Argopecten ventricosus, to investigate the effects of somatic growth, reproduction and aging on oxidative damage parameters (protein carbonyls, TBARS and lipofuscin) and cellular maintenance mechanisms (antioxidant activity and apoptosis) in scallops, caged in their natural environment. The concentrations of protein carbonyls and TBARS increased steeply during the early period of fast growth and during reproduction in one-year-old scallops. However, oxidative damage was transient, and apoptotic cell death played a pivotal role in eliminating damage in gill, mantle and muscle tissues of young scallops. Animals were able to reproduce again in the second year, but the reduced intensity of apoptosis impaired subsequent removal of damaged cells. In late survivors low antioxidant capacity and apoptotic activity together with a fast accumulation of the age pigment lipofuscin was observed. Rates of oxygen consumption and oxidative stress markers were strongly dependent on somatic growth and reproductive state but not on temperature. Compared to longer-lived bivalves, A. ventricosus seems more susceptible to oxidative stress with higher tissue-specific protein carbonyl levels and fast accumulation of lipofuscin in animals surviving the second spawning. Superoxide dismutase activity and apoptotic cell death intensity were however higher in this short-lived scallop than in longer-lived bivalves. The life strategy of this short-lived and intensely predated scallop supports rapid somatic growth and fitness as well as early maturation at young age at the cost of fast cellular degradation in second year scallops. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Growth, fledging success and post-fledging survival of juvenile Oystercatchers Haematopus ostralegus

    NARCIS (Netherlands)

    Kersten, Marcel; Brenninkmeijer, Alex

    We studied the consequences of differences in growth rate on the subsequent survival of Oystercatcher Haematopus ostralegus chicks. Fledging success increased sharply with growth rate, from zero in chicks growing at less than 6 g per day to about 85% in chicks growing at more than 10 g per day. The

  6. Population size, survival, growth, and movements of Rana sierrae

    Science.gov (United States)

    Fellers, Gary M.; Kleeman, Patrick M.; Miller, David A. W.; Halstead, Brian J.; Link, William

    2013-01-01

    Based on 2431 captures of 757 individual frogs over a 9-yr period, we found that the population of R. sierrae in one meadow–stream complex in Yosemite National Park ranged from an estimated 45 to 115 adult frogs. Rana sierrae at our relatively low elevation site (2200 m) grew at a fast rate (K = 0.73–0.78), had high overwintering survival rates (44.6–95%), lived a long time (up to 16 yr), and tended to be fairly sedentary during the summer (100% minimum convex polygon annual home ranges of 139 m2) but had low year-to-year site fidelity. Even though the amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd) has been present in the population for at least 13 yr, there was no clear downward trend as might be expected from reports of R. sierrae population declines associated with Bd or from reports of widespread population decline of R. sierrae throughout its range.

  7. Influence of season of birth on growth and reproductive development of Brahman bulls.

    Science.gov (United States)

    Tatman, Shawn R; Neuendorff, Don A; Wilson, Timothy W; Randel, Ronald D

    2004-07-01

    Seasonal effects on reproduction are more dramatic in Bos indicus than Bos taurus cattle. This experiment evaluated reproductive development of fall- (n=7) versus spring- (n = 10) born Brahman bulls to determine if season of birth affects reproductive development. Measurements of growth and reproductive development began after weaning and continued at bi-weekly intervals until each bull reached sexual maturity. Different stages of sexual development were classified according to characteristics of the ejaculate and included first sperm in the ejaculate, puberty (> 50 x 10(6) sperm/ejaculate), and sexual maturity (two ejaculates with > 500 = 10(6) sperm/ejaculate). Average daily increases in all measured traits were similar in fall- and spring-born bulls and there were no differences in age, body weight, scrotal circumference, or paired testis volume between groups at first sperm or puberty. However, fall-born bulls were older (P days versus 481 days, respectively) as the interval between puberty and sexual maturity was longer (P days versus 54 days, respectively). The prolonged interval between puberty and sexual maturity in fall-born calves coincided with a short photoperiod (winter) whereas the short interval between puberty and sexual maturity in spring-born calves coincided with a long photoperiod (summer). In conclusion, season of birth affected sexual development; photoperiod might be involved in regulating testicular function immediately after puberty in Brahman bulls.

  8. On the relationship between tumour growth rate and survival in non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Hitesh B. Mistry

    2017-11-01

    Full Text Available A recurrent question within oncology drug development is predicting phase III outcome for a new treatment using early clinical data. One approach to tackle this problem has been to derive metrics from mathematical models that describe tumour size dynamics termed re-growth rate and time to tumour re-growth. They have shown to be strong predictors of overall survival in numerous studies but there is debate about how these metrics are derived and if they are more predictive than empirical end-points. This work explores the issues raised in using model-derived metric as predictors for survival analyses. Re-growth rate and time to tumour re-growth were calculated for three large clinical studies by forward and reverse alignment. The latter involves re-aligning patients to their time of progression. Hence, it accounts for the time taken to estimate re-growth rate and time to tumour re-growth but also assesses if these predictors correlate to survival from the time of progression. I found that neither re-growth rate nor time to tumour re-growth correlated to survival using reverse alignment. This suggests that the dynamics of tumours up until disease progression has no relationship to survival post progression. For prediction of a phase III trial I found the metrics performed no better than empirical end-points. These results highlight that care must be taken when relating dynamics of tumour imaging to survival and that bench-marking new approaches to existing ones is essential.

  9. Reproduction and survival of a solitary bee along native and exotic floral resource gradients.

    Science.gov (United States)

    Palladini, Jennifer D; Maron, John L

    2014-11-01

    Native bee abundance has long been assumed to be limited by floral resources. This paradigm has been established in large measure because more bees are often found in areas supporting greater floral abundance. This could result from attraction to resource-rich sites as well as greater local demographic performance in sites supporting high floral abundance; however, demographic performance is usually unknown. Factors other than floral resources such as availability of nest sites, pressure from natural enemies, or whether floral resources are from a mixed native or mostly monodominant exotic assemblage might influence survival or fecundity and hence abundance. We examined how the survival and fecundity of the native solitary bee Osmia lignaria varied along a gradient in floral resource abundance. We released bees alongside a nest block at 27 grassland sites in Montana (USA) that varied in floral abundance and the extent of invasion by exotic forbs. We monitored nest construction and the fate of offspring within each nest. The number of nests established was positively related to native forb abundance and was negatively related to exotic forb species richness. Fecundity was positively related to native forb species richness; however, offspring mortality caused by the brood parasite Tricrania stansburyi was significantly greater in native-dominated sites. These results suggest that native floral resources can positively influence bee populations, but that the relationship between native floral resources and bee population performance is not straightforward. Rather, bees may face a trade-off between high offspring production and low offspring survival in native-dominated sites.

  10. Growth and Survival of Genetically Manipulated Lactobacillus plantarum in Silage

    OpenAIRE

    Sharp, R.; O'Donnell, A. G.; Gilbert, H. G.; Hazlewood, G. P.

    1992-01-01

    The growth and persistence of two genetically manipulated forms of Lactobacillus plantarum NCDO (National Collection of Dairy Organisms) 1193 have been monitored in grass silage. Both recombinants contained pSA3, a shuttle vector for gram-positive organisms that encodes erythromycin resistance. In one of the recombinants, pSA3 was integrated onto the chromosome, whereas in the other, a pSA3 derivative designated pM25, which contains a Clostridium thermocellum cellulase gene cloned into pSA3, ...

  11. Correlated growth and survival of juvenile spectacled eiders: Evidence of habitat limitation?

    Science.gov (United States)

    Flint, Paul L.; Morse, Julie A.; Grand, James B.; Moran, Christine L.

    2006-01-01

    We studied the growth and survival of Spectacled Eider (Somateria fischeri) ducklings to 30 days of age along the lower Kashunuk River on the Yukon-Kuskokwim Delta from 1995 to 2000. We replicated this study at a second site, Kigigak Island, in 1999 and 2000. Age-adjusted estimates of duckling mass and survival at 30 days posthatching were highly variable. Duckling survival was consistently higher on Kigigak Island in 1999 and 2000, averaging 67%, while survival on the Kashunuk River averaged 45% during the same time period. Duckling survival was negatively related to hatching date. At the Kashunuk River site our data supported models that indicated age-adjusted mass varied with habitat type and declined with hatching date. Ducklings from Kashunuk River were heavier in 1999, while ducklings from Kigigak Island were heavier in 2000. However, we found a positive correlation between 30-day duckling survival and age-adjusted mass, suggesting a localized environmental effect on both parameters. We conclude that predation may be the proximate mechanism of mortality, but habitat conditions are likely the ultimate factors influencing duckling survival. Geographic variation in rates of duckling survival and apparent growth suggest that spatial heterogeneity in population vital rates is occurring at multiple levels.

  12. Impact of habitat variability and altitude on growth dynamics and reproductive allocation in Ferula jaeschkeana Vatke

    Directory of Open Access Journals (Sweden)

    Ubaid Yaqoob

    2017-01-01

    Full Text Available Ferula jaeschkeana Vatke is an important threatened medicinal plant of the Himalayan region. The present study was carried out to determine the impact of the habitat variability and altitudinal gradient on the morphological and reproductive features of the species under study. The species exhibited great variability in its morphological traits under different environmental conditions. The plants were more vigorous and taller at a low altitude site, Kashmir University Botanical Garden (KUBG while the plants of a high altitude site, Gulmarg were shorter. With increased altitude, a significant reduction in the number of umbels per flowering stem, umbellules per umbel and flowers per umbellule occurred. An increase in the number of stigma and anthers was also observed in some plants at higher altitudes. Principal component analysis (PCA revealed that the habitat of KUBG and Dachigam proved relatively better for the growth of F. jaeschkeana. Maximum resources were allocated to the growth and development of the stem followed by root tubers, leaves and inflorescence. Reproductive success of the plant species varied along the altitudinal gradient and ranged from 64% to 72%. Increasing altitude resulted in a decrease in the allocation of biomass to reproductive structures in the form of decreasing dry weight. The total resource budget per plant was maximum in low altitude Drang (572.6 ± 158.36 g and Dachigam (568.4 ± 133.42 g populations and was least in the Gulmarg population (333.4 ± 82.89 g. The reproductive effort was higher (50.83% for the high altitude Gulmarg population. The regression analysis revealed a positive correlation and predicts that plant height has a direct impact on the umbel diameter and leaf length. Our results present a detailed account on the variation of growth characteristics, reproductive success and changes in allocation patterns in relation to the environmental conditions of this valuable medicinal plant species

  13. The regulation of reproductive neuroendocrine function by insulin and insulin-like growth factor-1 (IGF-1).

    Science.gov (United States)

    Wolfe, Andrew; Divall, Sara; Wu, Sheng

    2014-10-01

    The mammalian reproductive hormone axis regulates gonadal steroid hormone levels and gonadal function essential for reproduction. The neuroendocrine control of the axis integrates signals from a wide array of inputs. The regulatory pathways important for mediating these inputs have been the subject of numerous studies. One class of proteins that have been shown to mediate metabolic and growth signals to the CNS includes Insulin and IGF-1. These proteins are structurally related and can exert endocrine and growth factor like action via related receptor tyrosine kinases. The role that insulin and IGF-1 play in controlling the hypothalamus and pituitary and their role in regulating puberty and nutritional control of reproduction has been studied extensively. This review summarizes the in vitro and in vivo models that have been used to study these neuroendocrine structures and the influence of these growth factors on neuroendocrine control of reproduction. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Fibroblast growth factor receptor 4 (FGFR4) and fibroblast growth factor 19 (FGF19) autocrine enhance breast cancer cells survival.

    Science.gov (United States)

    Tiong, Kai Hung; Tan, Boon Shing; Choo, Heng Lungh; Chung, Felicia Fei-Lei; Hii, Ling-Wei; Tan, Si Hoey; Khor, Nelson Tze Woei; Wong, Shew Fung; See, Sze-Jia; Tan, Yuen-Fen; Rosli, Rozita; Cheong, Soon-Keng; Leong, Chee-Onn

    2016-09-06

    Basal-like breast cancer is an aggressive tumor subtype with poor prognosis. The discovery of underlying mechanisms mediating tumor cell survival, and the development of novel agents to target these pathways, is a priority for patients with basal-like breast cancer. From a functional screen to identify key drivers of basal-like breast cancer cell growth, we identified fibroblast growth factor receptor 4 (FGFR4) as a potential mediator of cell survival. We found that FGFR4 mediates cancer cell survival predominantly via activation of PI3K/AKT. Importantly, a subset of basal-like breast cancer cells also secrete fibroblast growth factor 19 (FGF19), a canonical ligand specific for FGFR4. siRNA-mediated silencing of FGF19 or neutralization of extracellular FGF19 by anti-FGF19 antibody (1A6) decreases AKT phosphorylation, suppresses cancer cell growth and enhances doxorubicin sensitivity only in the FGFR4+/FGF19+ breast cancer cells. Consistently, FGFR4/FGF19 co-expression was also observed in 82 out of 287 (28.6%) primary breast tumors, and their expression is strongly associated with AKT phosphorylation, Ki-67 staining, higher tumor stage and basal-like phenotype. In summary, our results demonstrated the presence of an FGFR4/FGF19 autocrine signaling that mediates the survival of a subset of basal-like breast cancer cells and suggest that inactivation of this autocrine loop may potentially serve as a novel therapeutic intervention for future treatment of breast cancers.

  15. Epidermal Growth Factor Receptor Is Related to Poor Survival in Glioblastomas: Single-Institution Experience

    Science.gov (United States)

    Choi, Youngmin; Lee, Hyung-Sik; Hur, Won-Joo; Sung, Ki-Han; Kim, Ki-Uk; Choi, Sun-Seob; Kim, Su-Jin; Kim, Dae-Cheol

    2013-01-01

    Purpose There are conflicting results surrounding the prognostic significance of epidermal growth factor receptor (EGFR) status in glioblastoma (GBM) patients. Accordingly, we attempted to assess the influence of EGFR expression on the survival of GBM patients receiving postoperative radiotherapy. Materials and Methods Thirty three GBM patients who had received surgery and postoperative radiotherapy at our institute, between March 1997 and February 2006, were included. The evaluation of EGFR expression with immunohistochemistry was available for 30 patients. Kaplan-Meier survival analysis and Cox regression were used for statistical analysis. Results EGFR was expressed in 23 patients (76.7%), and not expressed in seven (23.3%). Survival in EGFR expressing GBM patients was significantly less than that in non-expressing patients (median survival: 12.5 versus 17.5 months, p=0.013). Patients who received more than 60 Gy showed improved survival over those who received up to 60 Gy (median survival: 17.0 versus 9.0 months, p=0.000). Negative EGFR expression and a higher radiation dose were significantly correlated with improved survival on multivariate analysis. Survival rates showed no differences according to age, sex, and surgical extent. Conclusion The expression of EGFR demonstrated a significantly deleterious effect on the survival of GBM patients. Therefore, approaches targeting EGFR should be considered in potential treatment methods for GBM patients, in addition to current management strategies. PMID:23225805

  16. No evidence for a critical salinity threshold for growth and reproduction in the freshwater snail Physa acuta

    International Nuclear Information System (INIS)

    Kefford, Ben J.; Nugegoda, Dayanthi

    2005-01-01

    The growth and reproduction of the freshwater snail Physa acuta (Gastropoda: Physidae) were measured at various salinity levels (growth: distilled water, 50, 100, 500, 1000 and 5000 μS/cm; reproduction: deionized water, 100, 500, 1000 and 3000 μS/cm) established using the artificial sea salt, Ocean Nature. This was done to examine the assumption that there is no direct effect of salinity on freshwater animals until a threshold, beyond which sub-lethal effects, such as reduction in growth and reproduction, will occur. Growth of P. acuta was maximal in terms of live and dry mass at salinity levels 500-1000 μS/cm. The number of eggs produced per snail per day was maximal between 100 and 1000 μS/cm. Results show that rather than a threshold response to salinity, small rises in salinity (from low levels) can produce increased growth and reproduction until a maximum is reached. Beyond this salinity, further increases result in a decrease in growth and reproduction. Studies on the growth of freshwater invertebrates and fish have generally shown a similar lack of a threshold response. The implications for assessing the effects of salinisation on freshwater organisms need to be further considered. - Responses of snails to increasing salinity were non-linear

  17. No evidence for a critical salinity threshold for growth and reproduction in the freshwater snail Physa acuta.

    Science.gov (United States)

    Kefford, Ben J; Nugegoda, Dayanthi

    2005-04-01

    The growth and reproduction of the freshwater snail Physa acuta (Gastropoda: Physidae) were measured at various salinity levels (growth: distilled water, 50, 100, 500, 1000 and 5000 microS/cm; reproduction: deionized water, 100, 500, 1000 and 3000 microS/cm) established using the artificial sea salt, Ocean Nature. This was done to examine the assumption that there is no direct effect of salinity on freshwater animals until a threshold, beyond which sub-lethal effects, such as reduction in growth and reproduction, will occur. Growth of P. acuta was maximal in terms of live and dry mass at salinity levels 500-1000 microS/cm. The number of eggs produced per snail per day was maximal between 100 and 1000 microS/cm. Results show that rather than a threshold response to salinity, small rises in salinity (from low levels) can produce increased growth and reproduction until a maximum is reached. Beyond this salinity, further increases result in a decrease in growth and reproduction. Studies on the growth of freshwater invertebrates and fish have generally shown a similar lack of a threshold response. The implications for assessing the effects of salinisation on freshwater organisms need to be further considered.

  18. Survival and growth of eucalypts clones seedlings in response to organic fertilizer application

    Directory of Open Access Journals (Sweden)

    Sula Janaína de Oliveira Fernandes

    2011-12-01

    Full Text Available This work aimed to evaluate the effect of Fert-Bokashi® on survival and seedlings growth of two Eucalyptus urophylla clones propagated by minicutting technique. The experiment was conducted over a period of 28 days using a randomized block design and three replicates in an 6 x 2 factorial arrangement, with six Fert-Bokashi® concentrations (0.0%, 0.1%, 0.3%, 0.5%, 0.7% and 0.9% and two clones. Seedlings survival, height growth and shoot, root and total dry matter were evaluated. Experimental results demonstrated no significant effect of Fert- Bokashi® on survival and seedlings growth of two Eucalyptus urophylla clones.

  19. Growth and Survival of Some Probiotic Strains in Simulated Ice Cream Conditions

    Science.gov (United States)

    Homayouni, A.; Ehsani, M. R.; Azizi, A.; Razavi, S. H.; Yarmand, M. S.

    A Completely Randomized Design (CRD) experiment was applied in triplicates to evaluate the survival of four probiotic strains in simulated ice cream conditions. The growth and survival rate of these probiotic strains (Lactobacillus acidophilus, Lactobacillus casei, Bifidobacterium bifidum and Bifidobacterium longum) in varying amount of sucrose (10, 15, 20 and 25%), oxygen scavenging components (0.05% L-cysteine and 0.05% L-ascorbate) and temperatures (4 and -20°C) during different periods of time (1, 2 and 3 months) were evaluated in MRS-broth medium. Optical density at 580 nm was used to measure growth. Lactobacilli strains proved to be highly resistant in comparison with Biffidobacteria strains. The viable cell number of Lactobacillus casei in different sucrose concentrations, different oxidoreduction potentials and refrigeration temperature was 1x1010, 2x108 and 5x107 cfu mL-1, respectively. Growth and survival rate of Lactobacillus casei showed to be the highest.

  20. Effect of Lignite Fly Ash on the Growth and Reproduction of Earthworm Eisenia fetida

    Directory of Open Access Journals (Sweden)

    S. Sarojini

    2009-01-01

    Full Text Available Fly ash is an amorphous ferroalumino silicate, an important solid waste around thermal power plants. It creates problems leading to environmental degradation due to improper utilization or disposal. However, fly ash is a useful ameliorant that may improve the physical, chemical and biological properties of soils and is a source of readily available plant macro and micronutrients when it is used with biosolids. Supply of nutrients from fly ash with biosolids may enhance their agricultural use. The growth and reproduction of Eisenia fetida was studied during vermicomposting of fly ash with cowdung and pressmud in four different proportions (T1,T2,T3 & T4 and one control i.e., cow dung and pressmud alone. The growth, cocoon and hatchlings production were observed at the interval of 15 days over a period of 60 days. The maximum worm growth and reproduction was observed in bedding material alone. Next to that the T1 was observed as the best mixture for vermiculture.

  1. Morphometry, growth and reproduction of an Atlantic population of the razor clam Ensis macha (Molina, 1782

    Directory of Open Access Journals (Sweden)

    Pedro J. Barón

    2004-06-01

    Full Text Available Ensis macha is a razor clam distributed throughout the coasts of southern Argentina and Chile. Even though it represents a valuable fishery resource, the exploitation of its Atlantic populations has begun only in recent years. This study provides the first estimates of growth rate, an interpretation of the reproductive cycle on the coast of the northern Argentine Patagonia and an analysis of the species morphometry. Growth was estimated by direct observation of growth rings on the valves by two observers. The reproductive cycle was interpreted by the analysis of temporal change of oocyte size frequency distributions. Parameter estimations for the von Bertalanffy equations respectively obtained by observers 1 and 2 were 154 and 153.7 mm for L?, 0.25 and 0.20 yr-1 for k, and -0.08 and -0.72 yr for t0. Two spawning peaks were detected: September-November 1999 and May-June 2000. However, mature females were found all year round. An abrupt change in the relationship between shell length and height was detected at 11.2 mm length.

  2. SURVIVAL ANALYSIS AND GROWTH OF Cordia trichotoma, BORAGINACEAE, LAMIALES, IN MATO GROSSO DO SUL STATE, BRAZIL

    Directory of Open Access Journals (Sweden)

    Sergio Luiz Salvadori

    2013-12-01

    Full Text Available http://dx.doi.org/10.5902/1980509812357The evaluation of a plant survival percentage and growth may reflect its competitive ability in plantcommunity. Cordia trichotoma is a common native tree in Mato Grosso do Sul State and one of the mostpromising for planting. This study monitored the survival percentage and growth of Cordia trichotomaunder different conditions such as weeding and receiving or not fertilization. The experiment started inSeptember 2008 and it was concluded in March 2010. The seeds collection and sowing were held in urbanarea of Mundo Novo Municipality and the area for permanent planting to measure seedlings survival andgrowth was set at Japorã Municipality, Fazenda Santa Clara. Seedlings were planted in two categories: theuse or not of fertilizer and crowing resulting in four distinct groups: block fertilizer bare earth (ATN, bareland block without fertilizer (BTN, fertilizer and crown block (AC and without fertilizer and crownedblock (BC. The results indicated high survival of Cordia trichotoma in the seedling transplant system from bed to bags. The BC block showed the highest percentage of survival, but the smaller increments in height.The AC, ATN and BTN blocks presented the same survival pattern and similar average growth. However,there may be differences in nutritional and chemical composition of the soil suggesting sector analysis forfuture studies.

  3. Genetic correlations among and between wool, growth and reproduction traits in Merino sheep.

    Science.gov (United States)

    Safari, E; Fogarty, N M; Gilmour, A R; Atkins, K D; Mortimer, S I; Swan, A A; Brien, F D; Greeff, J C; van der Werf, J H J

    2007-04-01

    Data from seven research resource flocks across Australia were combined to provide accurate estimates of genetic correlations among production traits in Merino sheep. The flocks represented contemporary Australian Merino fine, medium and broad wool strains over the past 30 years. Over 110,000 records were available for analysis for each of the major wool traits, and 50,000 records for reproduction and growth traits with over 2700 sires and 25,000 dams. Individual models developed from the single trait analyses were extended to the various combinations of two-trait models to obtain genetic correlations among six wool traits [clean fleece weight (CFW), greasy fleece weight, fibre diameter (FD), yield, coefficient of variation of fibre diameter and standard deviation of fibre diameter], four growth traits [birth weight, weaning weight, yearling weight (YWT), and hogget weight] and four reproduction traits [fertility, litter size, lambs born per ewe joined, lambs weaned per ewe joined (LW/EJ)]. This study has provided for the first time a comprehensive matrix of genetic correlations among these 14 wool, growth and reproduction traits. The large size of the data set has also provided estimates with very low standard errors. A moderate positive genetic correlation was observed between CFW and FD (0.29 +/- 0.02). YWT was positively correlated with CFW (0.23 +/- 0.04), FD (0.17 +/- 0.04) and LWEJ (0.58 +/- 0.06), while LW/EJ was negatively correlated with CFW (-0.26 +/- 0.05) and positively correlated with FD (0.06 +/- 0.04) and LS (0.68 +/- 0.04). These genetic correlations, together with the estimates of heritability and other parameters provide the basis for more accurate prediction of outcomes in complex sheep-breeding programmes designed to improve several traits.

  4. Growth and Survival of Genetically Manipulated Lactobacillus plantarum in Silage.

    Science.gov (United States)

    Sharp, R; O'donnell, A G; Gilbert, H G; Hazlewood, G P

    1992-08-01

    The growth and persistence of two genetically manipulated forms of Lactobacillus plantarum NCDO (National Collection of Dairy Organisms) 1193 have been monitored in grass silage. Both recombinants contained pSA3, a shuttle vector for gram-positive organisms that encodes erythromycin resistance. In one of the recombinants, pSA3 was integrated onto the chromosome, whereas in the other, a pSA3 derivative designated pM25, which contains a Clostridium thermocellum cellulase gene cloned into pSA3, was maintained as an extrachromosomal element. This extrachromosomal element is a plasmid. Rifampin-resistant mutants were selected for the recombinants and the parent strain. When applied to minisilos at a rate of 10 CFU/g of grass, both the recombinants and the parent strain proliferated to dominate the epiphytic microflora and induced an increase in the decline in pH compared with that of the noninoculated silos. The presence of extra genetic material did not appear to disadvantage the bacterium in comparison with the parent strain. The selective recovery of both strains by using rifampin and erythromycin was confirmed by Southern hybridization. Interestingly, the free plasmid (pM25) appeared more stable in silage than was expected from studies in MRS broth. The plasmid was retained by 85% of the rifampin-resistant L. plantarum colonies isolated from a day 30 silo. These data answer an important question by showing that genetically manipulated recombinants of L. plantarum can proliferate and compete with epiphytic lactic acid bacteria in silage.

  5. Growth and Your 13-to 18-Year-Old

    Science.gov (United States)

    ... A Parent's Guide to Surviving the Teen Years Male Reproductive System Your Child's Checkup: 14 Years Your Child's Checkup: ... Height? When Will I Start Developing? Growth Problems Male Reproductive System Everything You Wanted to Know About Puberty Help! ...

  6. Interact to survive: Phyllobacterium brassicacearum improves Arabidopsis tolerance to severe water deficit and growth recovery.

    Directory of Open Access Journals (Sweden)

    Justine Bresson

    Full Text Available Mutualistic bacteria can alter plant phenotypes and confer new abilities to plants. Some plant growth-promoting rhizobacteria (PGPR are known to improve both plant growth and tolerance to multiple stresses, including drought, but reports on their effects on plant survival under severe water deficits are scarce. We investigated the effect of Phyllobacterium brassicacearum STM196 strain, a PGPR isolated from the rhizosphere of oilseed rape, on survival, growth and physiological responses of Arabidopsis thaliana to severe water deficits combining destructive and non-destructive high-throughput phenotyping. Soil inoculation with STM196 greatly increased the survival rate of A. thaliana under several scenarios of severe water deficit. Photosystem II efficiency, assessed at the whole-plant level by high-throughput fluorescence imaging (Fv/Fm, was related to the probability of survival and revealed that STM196 delayed plant mortality. Inoculated surviving plants tolerated more damages to the photosynthetic tissues through a delayed dehydration and a better tolerance to low water status. Importantly, STM196 allowed a better recovery of plant growth after rewatering and stressed plants reached a similar biomass at flowering than non-stressed plants. Our results highlight the importance of plant-bacteria interactions in plant responses to severe drought and provide a new avenue of investigations to improve drought tolerance in agriculture.

  7. Dispersal strategy of cyst nematodes (Heterodera arenaria) in the plant root zone of mobile dunes and consequences for emergence, survival and reproductive success

    NARCIS (Netherlands)

    Stoel, C.D.; Putten, van der W.H.

    2006-01-01

    Root-feeding nematodes may play an important role in generating spatial and temporal variation in natural plant communities, but little is known about the performance of the nematodes in the plant root zone. We studied the emergence, survival and reproductive success of the cyst nematode Heterodera

  8. Dispersal strategy of cyst nematodes (Heterodera Arenaria) in the plant root zone of mobile dunes and consequences for emergence, survival and reproductive success

    NARCIS (Netherlands)

    Van der Stoel, C.D.; Van der Putten, W.H.

    2006-01-01

    Root-feeding nematodes may play an important role in generating spatial and temporal variation in natural plant communities, but little is known about the performance of the nematodes in the plant root zone. We studied the emergence, survival and reproductive success of the cyst nematode Heterodera

  9. Mycorrhizal symbiosis increases growth, reproduction and recruitment of Abutilon theophrasti Medic. in the field.

    Science.gov (United States)

    Stanley, Margot R; Koide, Roger T; Shumway, Durland L

    1993-05-01

    We examined in the field the effect of the vesicular-arbuscular (VA) mycorhizal symbiosis on the reproductive success of Abutilon theophrasti Medic., an early successional annual member of the Malvaceae. Mycorrhizal infection greatly enhanced vegetative growth, and flower, fruit and seed production, resulting in significantly greater recruitment the following year. In addition, the seeds produced by mycorrhizal plants were significantly larger and contained significantly more phosphorus than seeds from non-mycorrhizal plants, an effect which may improve offspring vigor. Infection by mycorrhizal fungi may thus contribute to the overall fitness of a host plant and strongly influence long-term plant population dynamics.

  10. DNA alterations and effects on growth and reproduction in Daphnia magna during chronic exposure to gamma radiation over three successive generations

    Energy Technology Data Exchange (ETDEWEB)

    Parisot, Florian [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, St Paul-lez-Durance 13115 (France); Bourdineaud, Jean-Paul [UMR 5805 EPOC – OASU, Station marine d’Arcachon, Université Bordeaux 1, Arcachon 33120 (France); Plaire, Delphine; Adam-Guillermin, Christelle [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, St Paul-lez-Durance 13115 (France); Alonzo, Frédéric, E-mail: frederic.alonzo@irsn.fr [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-ENV/SERIS/LECO, Cadarache, St Paul-lez-Durance 13115 (France)

    2015-06-15

    Highlights: • We exposed three successive generations of Daphnia magna to chronic gamma radiation. • We examined DNA alterations and effects on survival, growth and reproduction. • DNA alterations were accumulated over a generation and transmitted to the progeny. • Effects on survival and reproduction, and delay in growth increased over generations. - Abstract: This study examined chronic effects of external Cs-137 gamma radiation on Daphnia magna exposed over three successive generations (F0, F1 and F2) to environmentally relevant dose rates (ranging from 0.007 to 35.4 mGy h{sup −1}). Investigated endpoints included survival, growth, reproduction and DNA alterations quantified using random-amplified polymorphic DNA polymerase chain reaction (RAPD-PCR). Results demonstrated that radiation effects on survival, growth and reproduction increased in severity from generation F0 to generation F2. Mortality after 21 days at 35.4 mGy h{sup −1} increased from 20% in F0 to 30% in F2. Growth was affected by a slight reduction in maximum length at 35.4 mGy h{sup −1} in F0 and by reductions of 5 and 13% in growth rate, respectively, at 4.70 and 35.4 mGy h{sup −1} in F2. Reproduction was affected by a reduction of 19% in 21 day-fecundity at 35.4 mGy h{sup −1} in F0 and by a delay of 1.9 days in brood release as low as 0.070 mGy h{sup −1} in F2. In parallel, DNA alterations became significant at decreasing dose rates over the course of F0 (from 4.70 mGy h{sup −1} at hatching to 0.007 mGy h{sup −1} after ∼21 days) and from F0 to F2 (0.070 mGy h{sup −1} at hatching to 0.007 mGy h{sup −1} after ∼21 days), demonstrating their rapid accumulation in F0 daphnids and their transmission to offspring generations. Transiently more efficient DNA repair leading to some recovery at the organism level was suggested in F1, with no effect on survival, a slight reduction of 12% in 21 day-fecundity at 35.4 mGy h{sup −1} and DNA alterations significant at highest

  11. Ten-Year Effect of Six Site-Preparation Treatments on Piedmont Loblolly Pine Survival and Growth

    Science.gov (United States)

    M. Boyd Edwards

    1994-01-01

    Limited information is available on growth responses to different levels of intensity for site preparation in the Piedmont. In the present study, six intensities of site preparation were compared for their effect on survival, height and diameter growth, total volume produced, and basal area per acre for the first 10 years after treatment. Rates of survival and growth...

  12. Re-translocation of boron in broccoli and lupin during early reproductive growth

    Energy Technology Data Exchange (ETDEWEB)

    Marentes, E; Shelp, B J [Univ. of Guelph, Dept. of Horticultural Science, Guelph, ON (Canada); Vanderpool, R A [USDA, Human Nutrition Research Center, Agricultural Research Service, ND (United States); [Spiers, G.A. Univ. of Guelph, Dept. of Land Resource Science, Guelph, ON (Canada)

    1997-06-01

    The objective of the present study was to determine if boron (B) re-translocation depends on plant-B status and external-B supply. The stable {sup 10}B isotope was supplied to the root system of broccoli (Brassica oleracea var. italica Plenck cv. Commander) and lupin (Lupinus albus L. cv. Ultra) plants to provide a quantitative picture of B distribution during early reproductive development. Regardless of the B regime (i.e. continuous supply with luxury, sufficient or deficient B; transfer at influorescence emergence from either a luxury- or sufficient-B supply to a deficient one) and whether {sup 10}B was acquired before or during influorescence development, a significant proportion of the B recovered in broccoli florest and lupin fruit was {sup 10}B enriched. B acquired during inflorescence development was an important source of B for reproductive structures, but the relative importance of B acquired before and after inflorescence emergence appeared to be species dependent. The occurrence of B re-translocation was not dependent upon the induction of B deficiency. The concentrations of B in phloem exsudates (0.38 to 0.03 mM) were 4- to 23-fold those in xylem sap, and more similar to the concentrations in the reproductive structures (0.86 to 0.07 mM) than those in source leaves (2.4 to 0.19 mM). The decreasing acropetal gradient of tissue-B concentrations with luxury-B supply declined dramatically or was reversed in plants grown with sufficient or deficient B. The data are consistent with B being a phloem-mobile element, and suggest that newly acquired B is particularly important during the early reproductive growth of plants. (au) 36 refs.

  13. Re-translocation of boron in broccoli and lupin during early reproductive growth

    International Nuclear Information System (INIS)

    Marentes, E.; Shelp, B.J.; Vanderpool, R.A.

    1997-01-01

    The objective of the present study was to determine if boron (B) re-translocation depends on plant-B status and external-B supply. The stable 10 B isotope was supplied to the root system of broccoli (Brassica oleracea var. italica Plenck cv. Commander) and lupin (Lupinus albus L. cv. Ultra) plants to provide a quantitative picture of B distribution during early reproductive development. Regardless of the B regime (i.e. continuous supply with luxury, sufficient or deficient B; transfer at influorescence emergence from either a luxury- or sufficient-B supply to a deficient one) and whether 10 B was acquired before or during influorescence development, a significant proportion of the B recovered in broccoli florest and lupin fruit was 10 B enriched. B acquired during inflorescence development was an important source of B for reproductive structures, but the relative importance of B acquired before and after inflorescence emergence appeared to be species dependent. The occurrence of B re-translocation was not dependent upon the induction of B deficiency. The concentrations of B in phloem exsudates (0.38 to 0.03 mM) were 4- to 23-fold those in xylem sap, and more similar to the concentrations in the reproductive structures (0.86 to 0.07 mM) than those in source leaves (2.4 to 0.19 mM). The decreasing acropetal gradient of tissue-B concentrations with luxury-B supply declined dramatically or was reversed in plants grown with sufficient or deficient B. The data are consistent with B being a phloem-mobile element, and suggest that newly acquired B is particularly important during the early reproductive growth of plants. (au) 36 refs

  14. Survival, growth and sexual maturation in Atlantic salmon exposed to infectious pancreatic necrosis

    DEFF Research Database (Denmark)

    Lillehammer, Marie; Ødegård, Jørgen; Madsen, Per

    2013-01-01

    tested on data consisting of 10 972 fish that died and 3959 survivors with recorded growth data. The most complex models (4 and 5) were multivariate normal-binary mixture models including growth, sexual maturity and field survival traits. Growth rate and liability of sexual maturation were treated as two...... identification of runts. Mixture models are commonly used to identify the underlying structures in such data, and the aim of this study was to develop Bayesian mixture models for the genetic analysis of health status (runt/healthy) of surviving fish from an IPN outbreak. Methods Five statistical models were......-component normal mixtures, assuming phenotypes originated from two potentially overlapping distributions, (runt/normal). Runt status was an unobserved binary trait. These models were compared to mixture models with fewer traits (Models 2 and 3) and a classical linear animal model for growth (Model 1). Results...

  15. Discrete survival model analysis of a couple’s smoking pattern and outcomes of assisted reproduction

    Directory of Open Access Journals (Sweden)

    Jose C. Vanegas

    2017-02-01

    Full Text Available Abstract Background Cigarette smoking has been associated with worse infertility treatment outcomes, yet some studies have found null or inconsistent results. Methods We followed 225 couples who underwent 354 fresh non-donor assisted reproductive technology (ART cycles between 2006 and 2014. Smoking history was self-reported at study entry. We evaluated the associations between smoking patterns and ART success using multivariable discrete time Cox proportional hazards models with six time periods: cycle initiation to egg retrieval, retrieval to fertilization, fertilization to embryo transfer (ET, ET to implantation, implantation to clinical pregnancy, and clinical pregnancy to live birth to estimate hazard ratios (HR and 95% CIs. Time-dependent interactions between smoking intensity and ART time period were used to identify vulnerable periods. Results Overall, 26% of women and 32% of men reported ever smoking. The HR of failing in the ART cycle without attaining live birth for male and female ever smokers was elevated, but non-significant, compared to never smokers regardless of intensity (HR = 1.02 and 1.30, respectively. Female ever smokers were more likely to fail prior to oocyte retrieval (HR: 3.37; 95% CI: 1.00, 12.73. Every one cigarette/day increase in smoking intensity for females was associated with a HR of 1.02 of failing ART (95% CI: 0.97, 1.08, regardless of duration or current smoking status. Women with higher smoking intensities were most likely to fail a cycle prior to oocyte retrieval (HR: 1.07; 95% CI: 1.00, 1.16. Among past smokers, every additional year since a man had quit smoking reduced the risk of failing ART by 4% (HR: 0.96; 95% CI: 0.91, 1.00 particularly between clinical pregnancy and live birth (HR: 0.86; 95% CI: 0.76, 0.96. Conclusions Female smoking intensity, regardless of current smoking status, is positively associated with the risk of failing ART cycles between initiation and oocyte retrieval. In men who ever

  16. Resource investments in reproductive growth proportionately limit investments in whole-tree vegetative growth in young olive trees with varying crop loads.

    Science.gov (United States)

    Rosati, Adolfo; Paoletti, Andrea; Al Hariri, Raeed; Morelli, Alessio; Famiani, Franco

    2018-02-21

    It has long been debated whether tree growth is source limited, or whether photosynthesis is adjusted to the actual sink demand, directly regulated by internal and environmental factors. Many studies support both possibilities, but no studies have provided quantitative data at the whole-tree level, across different cultivars and fruit load treatments. This study investigated the effect of different levels of reproductive growth on whole-tree biomass growth across two olive cultivars with different growth rates (i.e., Arbequina, slow-growing and Frantoio, fast-growing), over 2 years. Young trees of both cultivars were completely deflowered either in 2014, 2015, both years or never, providing a range of levels of cumulated reproductive growth over the 2 years. Total vegetative dry matter growth over the 2 years was assessed by destructive sampling (whole tree). Vegetative growth increased significantly less in fruiting trees, however, the total of vegetative and reproductive growth did not differ significantly for any treatment or cultivar. Vegetative growth over the 2 years was closely (R2 = 0.89) and inversely related to reproductive growth across all treatments and cultivars. When using data from 2015 only, the regression improved further (i.e., R2 = 0.99). When biomass was converted into grams of glucose equivalents, based on the chemical composition of the different parts, the results indicated that for every gram of glucose equivalent invested in reproductive growth, vegetative growth was reduced by 0.73-0.78 g of glucose equivalent. This indicates that competition for resources played a major role in determining tree growth, but also that photosynthesis was probably also enhanced at increasing fruit load (or downregulated at decreasing fruit load). The leaf area per unit of trunk cross sectional area increased with deflowering (i.e., decreased with reproductive growth), suggesting that water relations might have limited photosynthesis in deflowered plants

  17. The morphological growth patterns of colorectal liver metastases are prognostic for overall survival

    DEFF Research Database (Denmark)

    Nielsen, Kåre; Rolff, Hans C; Eefsen, Rikke L

    2014-01-01

    Colorectal metastases in the liver grow according to three histological patterns: a pushing pattern, a replacement pattern, and a desmoplastic pattern. The objective of the current study was to explore the prognostic significance of these three growth patterns for survival. The study included 217....... Eventually, the growth patterns may contribute to a histology-based prognostic biomarker for patients with colorectal liver metastases.Modern Pathology advance online publication, 23 May 2014; doi:10.1038/modpathol.2014.4....

  18. Impacts of maternal dietary protein intake on fetal survival, growth, and development.

    Science.gov (United States)

    Herring, Cassandra M; Bazer, Fuller W; Johnson, Gregory A; Wu, Guoyao

    2018-03-01

    Maternal nutrition during gestation, especially dietary protein intake, is a key determinant in embryonic survival, growth, and development. Low maternal dietary protein intake can cause embryonic losses, intra-uterine growth restriction, and reduced postnatal growth due to a deficiency in specific amino acids that are important for cell metabolism and function. Of note, high maternal dietary protein intake can also result in intra-uterine growth restriction and embryonic death, due to amino acid excesses, as well as the toxicity of ammonia, homocysteine, and H 2 S that are generated from amino acid catabolism. Maternal protein nutrition has a pronounced impact on fetal programming and alters the expression of genes in the fetal genome. As a precursor to the synthesis of molecules (e.g. nitric oxide, polyamines, and creatine) with cell signaling and metabolic functions, L-arginine (Arg) is essential during pregnancy for growth and development of the conceptus. With inadequate maternal dietary protein intake, Arg and other important amino acids are deficient in mother and fetus. Dietary supplementation of Arg during gestation has been effective in improving embryonic survival and development of the conceptus in many species, including humans, pigs, sheep, mice, and rats. Both the balance among amino acids and their quantity are critical for healthy pregnancies and offspring. Impact statement This review aims at: highlighting adverse effects of elevated levels of ammonia in mother or fetus on embryonic/fetal survival, growth, and development; helping nutritionists and practitioners to understand the mechanisms whereby elevated levels of ammonia in mother or fetus results in embryonic/fetal death, growth restriction, and developmental abnormalities; and bringing, into the attention of nutritionists and practitioners, the problems of excess or inadequate dietary intake of protein or amino acids on pregnancy outcomes in animals and humans. The article provides new

  19. Influence of plant maturity, shoot reproduction and sex on vegetative growth in the dioecious plant Urtica dioica.

    Science.gov (United States)

    Oñate, Marta; Munné-Bosch, Sergi

    2009-10-01

    Stinging nettle (Urtica dioica) is a herbaceous, dioecious perennial that is widely distributed around the world, reproduces both sexually and asexually, and is characterized by rapid growth. This work was aimed at evaluating the effects of plant maturity, shoot reproduction and sex on the growth of leaves and shoots. Growth rates of apical shoots, together with foliar levels of phytohormones (cytokinins, auxins, absicisic acid, jasmonic acid and salicylic acid) and other indicators of leaf physiology (water contents, photosynthetic pigments, alpha-tocopherol and F(v)/F(m) ratios) were measured in juvenile and mature plants, with a distinction made between reproductive and non-reproductive shoots in both males and females. Vegetative growth rates were not only evaluated in field-grown plants, but also in cuttings obtained from these plants. All measurements were performed during an active vegetative growth phase in autumn, a few months after mature plants reproduced during spring and summer. Vegetative growth rates in mature plants were drastically reduced compared with juvenile ones (48 % and 78 % for number of leaves and leaf biomass produced per day, respectively), which was associated with a loss of photosynthetic pigments (up to 24 % and 48 % for chlorophylls and carotenoids, respectively) and increases of alpha-tocopherol (up to 2.7-fold), while endogenous levels of phytohormones did not differ between mature and juvenile plants. Reductions in vegetative growth were particularly evident in reproductive shoots of mature plants, and occurred similarly in both males and females. It is concluded that (a) plant maturity reduces vegetative growth in U. dioica, (b) effects of plant maturity are evident both in reproductive and non-reproductive shoots, but particularly in the former, and (c) these changes occur similarly in both male and female plants.

  20. Bisphenol A in artificial soil: Effects on growth, reproduction and immunity in earthworms.

    Science.gov (United States)

    Verdú, I; Trigo, D; Martínez-Guitarte, J L; Novo, M

    2018-01-01

    The application of biosolids in agricultural fields is increasing annually. They contain not only nutrients but also xenobiotics, such as Bisphenol A (BPA). These compounds are not regulated in the use of biosolids in agriculture, which highlights the need to assess their effects on soil life, of which earthworms are most abundant of the animal representatives. In this study the effect of BPA on life-history parameters, such as mortality, growth and reproduction, and on immunity, is evaluated for Dendrobaena veneta and Eisenia fetida. Sublethal concentrations were evaluated by a modified OECD artificial soil test. Decline in growth with increasing concentration of BPA was detected during the first two weeks and the opposite effect for the next two, although these differences were only significant at the highest concentration. Reproduction traits were only significantly different for E. fetida, for which the number of juveniles decreased at higher concentrations, thus showing different sensitivity in both species. By using a contact test, the potentially harmful effect of direct contact with BPA was shown to be much higher than in soil (resembling natural) conditions. Finally, results indicate that BPA may not affect the immune system of these animals, at least in terms of coelomocyte viability. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Flooding tolerance in cotton (gossypium hirsutum l.) at early vegetative and reproductive growth stages

    International Nuclear Information System (INIS)

    Hussain, A.

    2014-01-01

    Periodic flooding at any growth stage greatly affects growth and yield of crops. In order to develop flooding tolerant cotton cultivar and to identify the most sensitive growth stage to periodic flooding, a field experiment was conducted in which 60-cultivars/accessions/lines were subjected to two week flooding at seedling/early vegetative, flower and boll formation growth stages. Pre- and post-flooding soil analysis was also carried out. Nitrate-N was greatly reduced due to flooding applied at all growth stages, whereas NH4-N increased significantly. Similarly, Fe and Mn were also increased to many folds in flooded soils. Under hypoxic conditions, depletion of nitrates and toxic effects of accumulated NH4, Fe and Mn caused severe damages to cotton plants and even death of plants. Of the three growth stages, early vegetative growth stage is most sensitive to two week flooding. Flooding imposed at the flowering and boll formation growth stages caused a substantial amount of yield penalty. On the basis of survival percentage, the 60-cultivars/accessions/lines were categorized into tolerant (61%), moderately tolerant (31=60%) and sensitive (31%) to short term flooding. At the seedling or early vegetative growth stage, genotypes DPL-SR-2 followed by 124-F and MNH-427 were most tolerant to flooding, while AET-5, N-KRISHMA, LRA-5166, CEDIX and H-142 were ranked as sensitive to flooding stress. At the flowering stage, the genotype NIAB-92 followed by S-14 and MNH-427 were highly tolerant to flooding. At the boll formation stage, genotypes DPL-70010-N followed by GH-11-9-75 and B-2918-2 were highly tolerant waterlogging. More than 50% of the genotypes maintained the degree of flooding tolerance at three growth stages. However, on the basis of survival percentage at three growth stages, genotypes MNH-564, FH-114, MNH-786 and CIM-573 were included in the tolerant group and the genotypes N-KRISHMA, LRA-5166, CEDIX and H-142 were included in the sensitive group. These

  2. Effects of feeding frequency variation on the growth and survival of ...

    African Journals Online (AJOL)

    Highest survival rate of 73.3% was recorded in fingerlings fed once in two days. The study showed that body composition of C. gariepinus fingerlings was influenced by the different feeding frequencies. Based on the growth performance recorded in this research, once in a day feeding frequency was the best to obtain the ...

  3. Effects of Water Replacement rate on Growth and Survival of the ...

    African Journals Online (AJOL)

    The influence of frequency of water replacement on growth performance and survival of the Nile tilapia,Oreochromis niloticus fry of mean 1.14g + 0.00 of the same brood stock reared in a static culture was investigated in the laboratory over a period of forty-two days. There were five treatments namely, treatment A = daily ...

  4. Early growth and survival of Acacia galpinii after planting in a semi ...

    African Journals Online (AJOL)

    Foliage transparency was in excess of 80% for all age groups while crown dieback and stem damage was below 5%. A. galpinii was found to be suitable for dry-zone afforestation. Key Words: Indigenous tree planting; Acacia galpinii; Growth rate; Survival rate; Tree health. Southern African Forestry Journal Issue 202 2004: ...

  5. The effects of varying sampling intervals on the growth and survival ...

    African Journals Online (AJOL)

    Four different sampling intervals were investigated during a six-week outdoor nursery management of Heterobranchus longifilis (Valenciennes, 1840) fry in outdoor concrete tanks in order to determine the most suitable sampling regime for maximum productivity in terms of optimum growth and survival of hatchlings and ...

  6. Growth and Survival of Hardwoods and Pine Interplanted with European Alder

    Science.gov (United States)

    William T. Plass

    1977-01-01

    European black alder is recommended for planting on many surface mine spoils in the eastern United States. It grows rapidly on a range of spoil types and contributes to soil enrichment by fixing nitrogen and providing a leaf fall rich in nutrients. This study evaluated the effect of alder on the survival and growth of five hardwood and five pine species. After 10...

  7. Sex-specific effects of yolk testosterone on survival, begging and growth of zebra finches

    NARCIS (Netherlands)

    von Engelhardt, N; Carere, C; Dijkstra, C; Groothuis, TGG

    2006-01-01

    Yolk androgens affect offspring hatching, begging, growth and survival in many bird species. If these effects are sex-specific, yolk androgen deposition may constitute a mechanism for differential investment in male and female offspring. We tested this hypothesis in zebra finches. In this species,

  8. How to measure the economic impacts of changes in growth, feed efficiency and survival in aquaculture

    NARCIS (Netherlands)

    Kankainen, M.; Setala, J.; Berrill, I.K.; Ruohonen, K.; Noble, C.; Schneider, O.

    2012-01-01

    In this article we introduce a variety of bio-economic models that can be used to calculate the economic benefits associated with improved productivity in aquaculture. In the aquaculture industry, three important biological productivity factors are growth, survival and feed efficiency. The

  9. Quantifying flooding effects on hardwood seedling survival and growth for bottomland restoration

    Science.gov (United States)

    John M. Kabrick; Daniel C. Dey; J.W. Van Sambeek; Mark V. Coggeshall; Douglass F. Jacobs

    2012-01-01

    Growing interest worldwide in bottomland hardwood restoration necessitates improved ecological understanding of flooding effects on forest tree seedlings using methodology that accurately reflects field conditions. We examined hardwood seedling survival and growth in an outdoor laboratory where the timing, depth, duration, and flow rate of flood water can be carefully...

  10. Effect of Salinity on the Survival and Growth of Rufiji Tilapia ...

    African Journals Online (AJOL)

    Abstract. Survival and growth of Rufiji tilapia (Oreochromis urolepis urolepis) fry were determined under controlled salinity conditions of 5, 15, 25 and 35 ppt for 56 days. Experiments were carried out in 12 concrete tanks of 1 m3 volume each with three replicates for each treatment. Data was recorded at fourteen days ...

  11. Grass or fern competition reduce growth and survival of planted tree seedlings

    Science.gov (United States)

    Larry H. McCormick; Todd W. Bowersox

    1997-01-01

    Bareroot seedlings of northern red oak, white ash, yellow-poplar and white pine were planted into herbaceous communities at three forested sites in central Pennsylvania that were clearcut 0 to 1 year earlier. Seedlings were grown 4 years in the presence and absence of either an established grass or hay-scented fern community. Survival and height growth were measured...

  12. Effect of Bacillus subtilis on the growth and survival rate of shrimp ...

    African Journals Online (AJOL)

    The effect ofBacillus subtilis, isolated from digestive tract of Macrobrachium rosenbergii was investigated on growth and survival rate of Litopenaeus vannamei during 60 days of culture. Sixteen aquaria with four replicates were used for treatments and controls. Treatment groups were consisted of Bacillus subtilis, isolated ...

  13. Effect of different commercial feeds on growth and survival of African ...

    African Journals Online (AJOL)

    Clarias gariepinus fingerlings with mean weight 10.63±0.25 g were fed five different commercial diets for eight weeks to determine the most suitable and efficient feed for growth and survival under controlled environmental conditions. The diets used were Multi feed, Ajanla feed, Vital feed, Coppens feed and ARAC feed.

  14. Agroforestry systems of timber species and cacao: survival and growth during the early stages

    Directory of Open Access Journals (Sweden)

    Wilmer Espinoza

    2013-08-01

    Full Text Available In recent times, increased emphasis has been placed on diversifying the types of trees to shade cacao (Theobromacacao L. and to achieve additional services. Agroforestry systems that include profitable and native timber trees are a viable alternative but it is necessary to understand the growth characteristics of these species under different environmental conditions. Thus, timber tree species selection should be based on plant responses to biotic and abiotic factors. The aims of this study were (1 to evaluate growth rates and leaf area indices of the four commercial timber species: Cordia thaisiana, Cedrela odorata, Swietenia macrophylla and Tabebuia rosea in conjunction with incidence of insect attacks and (2 to compare growth rates of four Venezuelan Criollo cacao cultivars planted under the shade of these four timber species during the first 36 months after establishment. Parameters monitored in timber trees were: survival rates, growth rates expressed as height and diameter at breast height and leaf area index. In the four Cacao cultivars: height and basal diameter. C. thaisiana and C. odorata had the fastest growth and the highest survival rates. Growth rates of timber trees will depend on their susceptibility to insect attacks as well as to total leaf area. All cacao cultivars showed higher growth rates under the shade of C. odorata. Growth rates of timber trees and cacao cultivars suggest that combinations of cacao and timber trees are a feasible agroforestry strategy in Venezuela.

  15. Development, survival and reproduction of Podisus nigrispinus (Dallas, 1851 (Heteroptera: Pentatomidae with salt and amino acids solutions supplementary diet

    Directory of Open Access Journals (Sweden)

    Simone Patrícia Carneiro Freitas

    2006-05-01

    Full Text Available This study presents the effect of a supplementary diet with amino acids and sodium chloride solutions in addition to prey on the development, survival and reproduction of the predator Podisus nigrispinus (Heteroptera, Pentatomidae. Both solutions showed deleterious effects on nymph survival, adult weight, female longevity, number of egg masses, eggs per female, eggs per egg mass and nymphs per female besides egg viability of P. nigrispinus when compared with diet with water and prey. When compared with plant supplements in the diet the use of amino acids and salt solutions for mass rearing of P. nigrispinus was inferior.O presente estudo mostra o efeito da suplementação alimentar com soluções de aminoácidos e salina (NaCl no desenvolvimento, sobrevivência e reprodução de Podisus nigrispinus (Dallas (Heteroptera: Pentatomidae. Ambas soluções causaram efeito deletério na sobrevivência ninfal, peso dos adultos, longevidade das fêmeas e nos números de posturas, de ovos/fêmea, de ovos/postura e de ninfas, bem como na viabilidade dos ovos de P. nigrispinus quando comparado com estes insetos que além de presa receberam água. Estes resultados são discutidos em comparação com o efeito positivo que a suplementação alimentar com plantas tem sido relatada para esses predadores e sugerem que o uso de plantas é melhor que a substituição por solução de aminoácidos em sistemas de criação em laboratório desses predadores.

  16. Effects of environmental conditions on growth and survival of Salmonella in pasteurized whole egg

    DEFF Research Database (Denmark)

    Jakociune, Dziuginta; Bisgaard, Magne; Hervé, Gaëlle

    2014-01-01

    This study investigated the influence of three parameters (time, temperature and NaCl concentration) on survival and four parameters (temperature, NaCl and lysozyme concentrations and pH) on growth of Salmonella enterica serovar Enteritidis (S. Enteritidis) in pasteurized whole egg (PWE). Doehlert......Cl at a fixed heating time of 120s, while maximum growth rate was estimated at 25°C and 0% of NaCl. pH and lysozyme concentration were shown not to influence growth performance significantly in the range of values studied. Results inform industry of the optimal pasteurization and storage parameters for liquid...

  17. Effects of gamma radiation on survival and reproduction of Callosobruchus chinensis (L.) (Coleoptera: Bruchidae)

    International Nuclear Information System (INIS)

    Hussain, T.; Imura, Osamu

    1989-01-01

    Studies on the effects of gamma radiation on different life stages of Callosobruchus chinensis were carried out in a growth chamber at 30±1degC and 70±2 % R.H. with 12:12 hr light and dark cycle. Eggs (1-, 2-, 3-, 4-, and 5-day-old), larvae (7- and 10-day-old), mature pupae (one day before adult eclosion) along with adzuki beans and 1-day-old adults were exposed to gamma radiation from a 60 Co source. Complete mortality of the 1-day-old eggs was obtained by exposure to 12 Gy, and a dose of 40 Gy caused 100 % mortality of the 7-day-old larvae after 24 hr of exposure. A dose of 640 Gy caused instant kill of the mature pupae and 1-day-old adults. The fecundity and fertility of adults irradiated either as mature pupae or 1-day-old adults decreased with the increase of the dose. Eggs, laid by females which had been exposed and/or had mates which had been exposed as mature pupae to 20 Gy or more, had negligible hatching rates. Complete sterility was obtained at 80 Gy in the 1-day-old adults. The sterilized males irradiated as 1-day-old at 80 Gy were capable of competing sexually with untreated ones. The percentage of egg hatch decreased as the ratio of sterile males to normal males increased, becoming less than 10 % at the ratios of 9 : 1 and 15 : 1. (author)

  18. Effects of gamma radiation on survival and reproduction of Callosobruchus chinensis (L.) (Coleoptera: Bruchidae)

    International Nuclear Information System (INIS)

    Hussain, T.; Imura, O.

    1989-01-01

    Studies on the effects of gamma radiation on different life stages of Callosobruchus chinensis were carried out in a growth chamber at 30 .+-. 1.degree.C and 70 .+-. 2% R.H. with a 12: 12 hr light and dark cycle. Eggs (1-, 2-, 3-, 4-, and 5-day-old), larvae (7- and 10-day-old), mature pupae (one day adult eclosion) along with adzuki beans and 1-day-old adults were exposed to gamma radiation from a 60Co source. Complete mortality of the 1-day-old eggs was obtained by exposure to 12 Gy, and a dose of 40 Gy caused 100% mortality of the 7-day-old larvae after 24 hr of exposure. A dose of 640 Gy caused instant kill of the mature pupae and 1-day-old adults. The fecundity and fertility of adults irradiated either as mature pupae or 1-day-old adults decreased with the increase of the dose. Eggs, laid by females which had been exposed and/or had mates which had been exposed as mature pupae to 20 Gy or more, had negligible hatching rates. Complete sterility was obtained at 80 Gy in the 1-day-old adults. The sterilized males irradiated as 1-day-old at 80 gy were capable of competing sexually with untreated ones. The percentage of egg hatch decreased as the ratio of sterile males to normal males increased, becoming less than 10% at the ratios of 9:1 and 15:1

  19. [Effects of Cuscuta australis parasitism on the growth, reproduction and defense of Solidago canadensis].

    Science.gov (United States)

    Yang, Bei-fen; Du, Le-shan; Li, Jun-min

    2015-11-01

    In order to find out how parasitic Cuscuta australis influences the growth and reproduction of Solidago canadensis, the effects of the parasitism of C. australis on the morphological, growth and reproductive traits of S. canadensis were examined and the relationships between the biomass and the contents of the secondary metabolites were analyzed. The results showed that the parasitism significantly reduced the plant height, basal diameter, root length, root diameter, root biomass, stem biomass, leaf biomass, total biomass, number of inflorescences branches, axis length of inflorescence, and number of inflorescence. In particular, plant height, number of inflorescence and the stem biomass of parasitized S. canadensis were only 1/2, 1/5 and 1/8 of non-parasitized plants, respectively. There was no significant difference of plant height, root length, stem biomass and total biomass between plants parasitized with high and low intensities. But the basal diameter, root volume, leaf biomass, root biomass, the number of inflorescences branches, axis length of inflorescence and number of inflorescence of S. canadensis parasitized with high intensity were significantly lower than those of plants parasitized with low intensity. The parasitism of C. australis significantly increased the tannins content in the root and the flavonoids content in the stem of S. canadensis. The biomass of S. canadensis was significantly negatively correlated with the tannin content in the root and the flavonoids content in the stem. These results indicated that the parasitism of C. australis could inhibit the growth of S. canadensis by changing the resources allocation patterns as well as reducing the resources obtained by S. canadensis.

  20. Long-term effects of antibiotics, norfloxacin, and sulfamethoxazole, in a partial life-cycle study with zebrafish (Danio rerio): effects on growth, development, and reproduction.

    Science.gov (United States)

    Yan, Zhenhua; Lu, Guanghua; Ye, Qiuxia; Liu, Jianchao

    2016-09-01

    A partial life-cycle study with zebrafish (Danio rerio) was conducted to evaluate the long-term effects of antibiotics, norfloxacin (NOR) and sulfamethoxazole (SMX). A series of bio-endpoints correlated to the growth, development, and reproduction was assessed. The results showed that the body weight and the condition factor were depressed by SMX at 200 μg/L during the growth period. Meanwhile, the activities of metabolic enzyme (ethoxyresorufin O-deethylase, EROD) and antioxidant enzymes (superoxide dismutase, SOD and catalase, CAT) were stimulated in all cases. The consequences of parental exposure to antibiotics for the next generation were also examined. The egg production of parents were depressed by the 200 μg/L NOR and SMX alone or in combination. Similarly, decreased hatching, survival, and enhanced development abnormality of the next generation also occurred after parental exposure to SMX at the highest concentration. The heartbeat however was not altered in all cases. Furthermore, there was no significant difference in the bio-endpoints between the combined and individual treatment in most cases, with the exception of lower EROD activity and egg production in the co-treatment. The results suggest that long-term exposure to NOR and SMX at environmentally relevant concentrations, individually and in a mixture, may not significantly pose a threat to the growth, development, and reproduction of zebrafish, and an adverse effect may be expected at high concentration.

  1. The bifunctional autophagic flux by 2-deoxyglucose to control survival or growth of prostate cancer cells

    International Nuclear Information System (INIS)

    Jeon, Jeong Yong; Kim, Seung Won; Park, Ki Cheong; Yun, Mijin

    2015-01-01

    Recent reports using metabolism regulating drugs showed that nutrient deprivation was an efficient tool to suppress cancer progression. In addition, autophagy control is emerging to prevent cancer cell survival. Autophagy breaks down the unnecessary cytoplasmic components into anabolic units and energy sources, which are the most important sources for making the ATP that maintains homeostasis in cancer cell growth and survival. Therefore, the glucose analog 2-deoxyglucose (2DG) has been used as an anticancer reagent due to its inhibition of glycolysis. Prostate cancer cells (PC3) were treated with 2DG for 6 h or 48 h to analyze the changing of cell cycle and autophagic flux. Rapamycin and LC3B overexpressing vectors were administered to PC3 cells for autophagy induction and chloroquine and shBeclin1 plasmid were used to inhibit autophagy in PC3 cells to analyze PC3 cells growth and survival. The samples for western blotting were prepared in each culture condition to confirm the expression level of autophagy related and regulating proteins. We demonstrated that 2DG inhibits PC3 cells growth and had discriminating effects on autophagy regulation based on the different time period of 2DG treatment to control cell survival. Short-term treatment of 2DG induced autophagic flux, which increased microtubule associated protein 1 light chain 3B (LC3B) conversion rates and reduced p62 levels. However, 2DG induced autophagic flux is remarkably reduced over an extended time period of 2DG treatment for 48 h despite autophagy inducing internal signaling being maintained. The relationship between cell growth and autophagy was proved. Increased autophagic flux by rapamycin or LC3B overexpression powerfully reduced cell growth, while autophagy inhibition with shBeclin1 plasmid or chloroquine had no significant effect on regulating cell growth. Given these results, maintaining increased autophagic flux was more effective at inhibiting cancer cell progression than inhibition of

  2. Microaerobic growth and anaerobic survival of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium scrofulaceum

    Directory of Open Access Journals (Sweden)

    Amy Herndon Lewis

    2015-01-01

    Full Text Available Representative strains of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium scrofulaceum (MAIS grew at equal rates in laboratory medium at 21% (air and 12% oxygen. Growth in 6% oxygen proceeded at a 1.4–1.8-fold lower rate. Colony formation was the same at 21% (air and 6% oxygen. The MAIS strains survived rapid shifts from aerobic to anaerobic conditions as measured by two experimental approaches (Falkinham (1996 [1]. MAIS cells grown aerobically to log phase in broth were diluted, spread on agar medium, and incubated anaerobically for up to 20 days at 37 °C. Although no colonies formed anaerobically, upon transfer to aerobic conditions, greater than 25% of the colony forming units (CFU survived after 20 days of anaerobic incubation (Prince et al. (1989 [2]. MAIS cells grown in broth aerobically to log phase were sealed and vigorous agitation led to oxygen depletion (Wayne model. After 12 days anaerobic incubation, M. avium and M. scrofulaceum survival were high (>50%, while M. intracellulare survival was lower (22%. M. avium cells shifted to anaerobiosis in broth had increased levels of glycine dehydrogenase and isocitrate lyase. Growth of MAIS strains at low oxygen levels and their survival following a rapid shift to anaerobiosis is consistent with their presence in environments with fluctuating oxygen levels.

  3. Microaerobic growth and anaerobic survival of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium scrofulaceum.

    Science.gov (United States)

    Lewis, Amy Herndon; Falkinham, Joseph O

    2015-03-01

    Representative strains of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium scrofulaceum (MAIS) grew at equal rates in laboratory medium at 21% (air) and 12% oxygen. Growth in 6% oxygen proceeded at a 1.4-1.8-fold lower rate. Colony formation was the same at 21% (air) and 6% oxygen. The MAIS strains survived rapid shifts from aerobic to anaerobic conditions as measured by two experimental approaches (Falkinham (1996) [1]). MAIS cells grown aerobically to log phase in broth were diluted, spread on agar medium, and incubated anaerobically for up to 20 days at 37°C. Although no colonies formed anaerobically, upon transfer to aerobic conditions, greater than 25% of the colony forming units (CFU) survived after 20 days of anaerobic incubation (Prince et al. (1989) [2]). MAIS cells grown in broth aerobically to log phase were sealed and vigorous agitation led to oxygen depletion (Wayne model). After 12 days anaerobic incubation, M. avium and M. scrofulaceum survival were high (>50%), while M. intracellulare survival was lower (22%). M. avium cells shifted to anaerobiosis in broth had increased levels of glycine dehydrogenase and isocitrate lyase. Growth of MAIS strains at low oxygen levels and their survival following a rapid shift to anaerobiosis is consistent with their presence in environments with fluctuating oxygen levels. Copyright © 2015 Asian African Society for Mycobacteriology. Published by Elsevier Ltd. All rights reserved.

  4. EGFR overexpressing cells and tumors are dependent on autophagy for growth and survival

    International Nuclear Information System (INIS)

    Jutten, Barry; Keulers, Tom G.; Schaaf, Marco B.E.; Savelkouls, Kim; Theys, Jan; Span, Paul N.; Vooijs, Marc A.; Bussink, Johan; Rouschop, Kasper M.A.

    2013-01-01

    Background and purpose: The epidermal growth factor receptor (EGFR) is overexpressed, amplified or mutated in various human epithelial tumors, and is associated with tumor aggressiveness and therapy resistance. Autophagy activation provides a survival advantage for cells in the tumor microenvironment. In the current study, we assessed the potential of autophagy inhibition (using chloroquine (CQ)) in treatment of EGFR expressing tumors. Material and methods: Quantitative PCR, immunohistochemistry, clonogenic survival, proliferation assays and in vivo tumor growth were used to assess this potential. Results: We show that EGFR overexpressing xenografts are sensitive to CQ treatment and are sensitized to irradiation by autophagy inhibition. In HNSSC xenografts, a correlation between EGFR and expression of the autophagy marker LC3b is observed, suggesting a role for autophagy in EGFR expressing tumors. This observation was substantiated in cell lines, showing high EGFR expressing cells to be more sensitive to CQ addition as reflected by decreased proliferation and survival. Surprisingly high EGFR expressing cells display a lower autophagic flux. Conclusions: The EGFR high expressing cells and tumors investigated in this study are highly dependent on autophagy for growth and survival. Inhibition of autophagy may therefore provide a novel treatment opportunity for EGFR overexpressing tumors

  5. Efficiency of probiotics (Ecoforce in the growth and survival of Peneaus monodon

    Directory of Open Access Journals (Sweden)

    V. Elumalai

    2013-12-01

    Full Text Available Probiotic supplementation of live microorganisms in aquaculture aids in preventing disease, thereby increasing production and decreasing economic loss. Application of probiotics bacteria in aquaculture systems plays significant role that determines the fate and success rate of culture. The present study was carried out to evaluate the performance of commercially available probiotics (The major active ingredients include Streptococcus faecalis, Streptococcus faecium, Bacillus mesentericus, Bacillus subtilis, Bacillus natto, Clostridium butyricum, Saccharomyces cerevivisiae, Alkaline Protease and Lipase in the growth and survival of Peneaus monodon in grow-out conditions. At the end of the culture, the survival rate of Pond I (treatment pond was 76%, whereas for Pond II (control pond it was only 59%. Pond I (29.2g where as shrimps in the Pond II showed the least average body weight of 22.6g. It is evident that application of probiotics has improved the growth and survival of P. monodon and which in turn paved way to reap better profit for the farmers. This investigation showed that administration of mixed Bacillus probiotics significantly improved growth and survival of shrimp, increased beneficial bacteria in shrimp culture and enhanced water quality for parameter., it seems likely that the use of probiotics will gradually increase in the days to come that will open new vistas in the arena of aquaculture.

  6. Mechanosensation Dynamically Coordinates Polar Growth and Cell Wall Assembly to Promote Cell Survival.

    Science.gov (United States)

    Davì, Valeria; Tanimoto, Hirokazu; Ershov, Dmitry; Haupt, Armin; De Belly, Henry; Le Borgne, Rémi; Couturier, Etienne; Boudaoud, Arezki; Minc, Nicolas

    2018-04-23

    How growing cells cope with size expansion while ensuring mechanical integrity is not known. In walled cells, such as those of microbes and plants, growth and viability are both supported by a thin and rigid encasing cell wall (CW). We deciphered the dynamic mechanisms controlling wall surface assembly during cell growth, using a sub-resolution microscopy approach to monitor CW thickness in live rod-shaped fission yeast cells. We found that polar cell growth yielded wall thinning and that thickness negatively influenced growth. Thickness at growing tips exhibited a fluctuating behavior with thickening phases followed by thinning phases, indicative of a delayed feedback promoting thickness homeostasis. This feedback was mediated by mechanosensing through the CW integrity pathway, which probes strain in the wall to adjust synthase localization and activity to surface growth. Mutants defective in thickness homeostasis lysed by rupturing the wall, demonstrating its pivotal role for walled cell survival. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. Feeding, growth, and survival of post-larval abalone Haliotis asinina on different benthic diatoms

    Directory of Open Access Journals (Sweden)

    Emmanuel C. Capinpin, Jr.

    2007-12-01

    Full Text Available The feeding behavior, digestive efficiency, growth, and survival of post-larval abalone Haliotis asininafed with 5 species of locally isolated benthic diatom strains (Navicula mollis, N. ramosissima, Stauroneissp., Pleurosigma sp., and Cocconeis sp. were examined in the laboratory. Two 15-day feeding trialsusing 1 mm post-larvae were conducted. No significant differences were observed in sizes of post-larvalabalone after 15 days in all diatom treatments (P>0.05. However, in both trials, Cocconeis sp. resulted inhigh survival rates (88.9±5.6% and 80.0±20.0% for Trials 1 and 2, respectively. Cocconeis sp. wasefficiently digested by post-larval abalone, with most of the cells being ruptured during ingestion and/orpassage through the gut. One diatom strain, Pleurosigma sp., resulted to a high survival but producedthe slowest growth rate (<10 ìm.d-1 SL. It was probably not ingested easily during the experiment due toits large size or mobility. For the other diatom strains, N. mollis and N. ramosissima, most cells passedthrough the gut with the cells left intact. Stauroneis sp. is highly digestible, but did not result to highsurvival, although the remaining live post-larval abalone fed on this diatom as well as on N. mollis grewfaster during the second week of both feeding trials. N. ramosissima resulted to poorest survival rate(<10% due to its poor digestibility. Only Cocconeis sp. showed a fairly high growth rate, digestionefficiency, and survival rate. N. mollis which gave a fairly high survival rate and Stauroneis may be addedtowards the later stages of post-larval rearing as well as other large diatoms. The digestion efficiency ofdiatom strains is considered an important factor determining its dietary value, but other factors may alsobe important such as volume contents, biochemical composition, and other physical characteristics.

  8. The sublethal effects of the organochlorines dieldrin and lindane on growth and reproduction of Eudrilus eugeniae and Eisenia fetida (Oligochaeta

    Directory of Open Access Journals (Sweden)

    Editorial Office

    1994-07-01

    Full Text Available Experimental exposure of the earthworm species Eudrilus eugeniae to organochlorines showed that dieldrin causes damage to sperm ultrastructure when viewed electronmicroscopically. Worms containing concentrations of 7,27 mg/kg dieldrin and higher showed more than 10% sperm damage. Exposure of Eisenia fetida to sublethal concentrations of lindane did not result in sperm damage but demonstrated an increase in growth and reproductive activity. It is argued that quantification of sperm damage and correlation with pesticide concentration could provide a useful tool for evaluating environmental quality. Furthermore, the effects of sublethal concentrations of pesticides that manifest themselves in increased growth and reproductive activity could affect ecological balances.

  9. Reproduction and Growth in a Murine Model of Early Life-Onset Inflammatory Bowel Disease.

    Directory of Open Access Journals (Sweden)

    Eniko Nagy

    Full Text Available Studies in transgenic murine models have provided insight into the complexity underlying inflammatory bowel disease (IBD, a disease hypothesized to result from an injurious immune response against intestinal microbiota. We recently developed a mouse model of IBD that phenotypically and histologically resembles human childhood-onset ulcerative colitis (UC, using mice that are genetically modified to be deficient in the cytokines TNF and IL-10 ("T/I" mice. Here we report the effects of early life onset of colon inflammation on growth and reproductive performance of T/I mice. T/I dams with colitis often failed to get pregnant or had small litters with pups that failed to thrive. Production was optimized by breeding double homozygous mutant T/I males to females homozygous mutant for TNF deficiency and heterozygous for deficiency of IL-10 ("T/I-het" dams that were not susceptible to spontaneous colon inflammation. When born to healthy (T/I-het dams, T/I pups initially gained weight similarly to wild type (WT pups and to their non-colitis-susceptible T/I-het littermates. However, their growth curves diverged between 8 and 13 weeks, when most T/I mice had developed moderate to severe colitis. The observed growth failure in T/I mice occurred despite a significant increase in their food consumption and in the absence of protein loss in the stool. This was not due to TNF-induced anorexia or altered food consumption due to elevated leptin levels. Metabolic studies demonstrated increased consumption of oxygen and water and increased production of heat and CO2 in T/I mice compared to their T/I-het littermates, without differences in motor activity. Based on the clinical similarities of this early life onset model of IBD in T/I mice to human IBD, these results suggest that mechanisms previously hypothesized to explain growth failure in children with IBD require re-evaluation. The T/I mouse model may be useful for further investigation of such mechanisms and

  10. Expression of nerve growth factor and heme oxygenase-1 predict poor survival of breast carcinoma patients

    International Nuclear Information System (INIS)

    Noh, Sang Jae; Chung, Myoung Ja; Moon, Woo Sung; Kang, Myoung Jae; Jang, Kyu Yun; Bae, Jun Sang; Jamiyandorj, Urangoo; Park, Ho Sung; Kwon, Keun Sang; Jung, Sung Hoo; Youn, Hyun Jo; Lee, Ho; Park, Byung-Hyun

    2013-01-01

    Nerve growth factor (NGF) is a neurotrophin and has been suggested to induce heme oxygenase-1 (HO1) expression. Although the role of HO1 in tumorigenesis remains controversial, recent evidence suggests NGF and HO1 as tumor-progressing factors. However, the correlative role of NGF and HO1 and their prognostic impact in breast carcinoma is unknown. We investigated the expression and prognostic significance of the expression of NGF and HO1 in 145 cases of breast carcinoma. Immunohistochemical expression of NGF and HO1 was observed in 31% and 49% of breast carcinoma, respectively. The expression of NGF and HO1 significantly associated with each other, and both have a significant association with histologic grade, HER2 expression, and latent distant metastasis. The expression of NGF and HO1 predicted shorter overall survival of breast carcinoma by univariate and multivariate analysis. NGF expression was an independent prognostic indicator for relapse-free survival by multivariate analysis. The combined expression pattern of NGF and HO1 was also an independent prognostic indicator of overall survival and relapse-free survival. The patients with tumors expressing NGF had the shortest survival and the patients with tumor, which did not express NGF or HO1 showed the longest survival time. This study has demonstrated that individual expression of NGF or HO1, and the combined NGF/HO1 expression pattern could be prognostic indicators for breast carcinoma patients

  11. Long-term monitoring of Sacramento Shade program trees: tree survival, growth and energy-saving performance

    Science.gov (United States)

    Yekang Ko; Jun-Hak Lee; E. Gregory McPherson; Lara A. Roman

    2015-01-01

    Long-term survival and growth of urban forests are critical to achieve the targeted benefits of urban tree planting programs, such as building energy savings from tree shade. However, little is known about how trees perform in the long-term, especially in residential areas. Given this gap in the literature, we monitored 22-years of post-planting survival, growth, and...

  12. The Risk of Growing Fast: Does fast growth have a negative impact on the survival rates of firms?

    NARCIS (Netherlands)

    Zhou, Haibo; van der Zwan, Peter; de Kok, Jan; Hartog, Chantal

    2012-01-01

    Fast-growing firms are considered as the central drivers of job creation in the economy. There is an abundance of literature on the separate subjects of firm growth and firm survival. However, the relationship between survival and growth is neglected. Using the Dutch Longitudinal Enterprise Database

  13. Effects of gamma radiation on the survival and growth of brine shrimp, Artemia salina

    International Nuclear Information System (INIS)

    Engel, D.W.; Davis, E.M.

    1976-01-01

    To determine the effects of gamma radiation on the survival and growth of brine shrimp, nauplii and adults were exposed to different doses of radiation and maintained at different salinities and temperatures. The LD 50 determination demonstrated that nauplii were thirty to forty times more sensitive than the adults and had a 25-day LD 50 of 450 rads. Radiation and salinity reduced survival of adult female brine shrimp more than the males. The interaction of salinity, 5 and 50 ppt, temperature, 10, 20 and 30 0 C, and radiation, 25 to 100 kilorads, decreased the survival of both male and female brine shrimp, with the males having the greater sensitivity. Brine shrimp nauplii irradiated with doses of 500 and 2,500 rads had accelerated growth and matured earlier than the controls. A test of the effect of crowding on growth showed that volume per individual was important, and a dose of 500 rads accelerated brine shrimp growth in all concentrations, with the greatest increase at 8 ml/nauplius

  14. Caenorhabditis elegans as a Model for Toxic Effects of Nanoparticles: Lethality, Growth, and Reproduction.

    Science.gov (United States)

    Maurer, Laura L; Ryde, Ian T; Yang, Xinyu; Meyer, Joel N

    2015-11-02

    The nematode Caenorhabditis elegans is extensively utilized in toxicity studies. C. elegans offers a high degree of homology with higher organisms, and its ease of use and relatively inexpensive maintenance have made it an attractive complement to mammalian and ecotoxicological models. C. elegans provides multiple benefits, including the opportunity to perform relatively high-throughput assays on whole organisms, a wide range of genetic tools permitting investigation of mechanisms and genetic sensitivity, and transparent bodies that facilitate toxicokinetic studies. This unit describes protocols for three nanotoxicity assays in C. elegans: lethality, growth, and reproduction. This unit focuses on how to use these well-established assays with nanoparticles, which are being produced in ever-increasing volume and exhibit physicochemical properties that require alteration of standard toxicity assays. These assays permit a broad phenotypic assessment of nanotoxicity in C. elegans, and, when used in combination with genetic tools and other assays, also permit mechanistic insight. Copyright © 2015 John Wiley & Sons, Inc.

  15. Insulin-like growth factor-I as a possible hormonal mediator of nutritional regulation of reproduction in cattle.

    Science.gov (United States)

    Zulu, Victor Chisha; Nakao, Toshihiko; Sawamukai, Yutaka

    2002-08-01

    The current review aims to establish insulin-like growth factor-1 (IGF-I) as the factor that signals nutritional status to the reproductive axis, and show that assessment of IGF-I in blood early postpartum during the negative energy balance (NEB) period could be used to predict both nutritional and reproductive status in dairy cattle. The review also explores the effect of nutritional status on circulating IGF-I concentrations and the endocrine role of IGF-I on the reproductive axis. IGF-I plays an important role in gonadotropin-induced folliculogenesis, ovarian steroidogenesis and corpus luteum (CL) function. It also modulates pituitary and hypothalamus function. IGF-I clearly has an endocrine role on the reproductive axis. Severe under nutrition significantly reduces plasma IGF-I concentrations. During the critical period of NEB in high yielding dairy cattle early postpartum, IGF-I concentrations are low in blood and its levels are positively correlated to energy status and reproductive function during this period. Changes in circulating IGF-I immediately postpartum may help predict both nutritional and reproductive status in dairy cattle. IGF-I is therefore one of the long sought factors that signal nutritional status to the reproductive axis.

  16. Predation risk affects growth and reproduction of an invasive snail and its lethal effect depends on prey size

    Science.gov (United States)

    Guo, Jing; Martín, Pablo R.; Zhang, Chunxia

    2017-01-01

    The behavior of invasive species under predation risk has been studied extensively, but their growth and reproductive responses have rarely been investigated. We conducted experiments with juveniles and adults of the invasive freshwater snail Pomacea canaliculata, and we observed changes in growth and reproduction in response to predation risk from a caged predator (Trachemys scripta elegans). P. canaliculata produced eggs earlier in the presence of predators and injured conspecifics compared with the control group (no risk), although the total number of egg masses laid by per female was exceeded by that of the controls after 15 days. Egg hatching success noticeably decreased under predation risk, and the incubation period was significantly prolonged; however, the oviposition height of the snails was not affected. A lethal effect of predation risk was detected in juvenile snails but not in adults. The growth of juvenile P. canaliculata was inhibited under predation risk, probably due to a reduction in food intake. Adult females exhibited a greater reduction in growth under predation risk than males, which likely resulted in part from the high reproductive investment of females in egg laying. These results indicate that P. canaliculata snails under predation risk face a trade-off between predator avoidance and growth and reproduction, where the lethal effect of predation risk is linked to the size of the prey. PMID:29136660

  17. Predation risk affects growth and reproduction of an invasive snail and its lethal effect depends on prey size.

    Directory of Open Access Journals (Sweden)

    Jing Guo

    Full Text Available The behavior of invasive species under predation risk has been studied extensively, but their growth and reproductive responses have rarely been investigated. We conducted experiments with juveniles and adults of the invasive freshwater snail Pomacea canaliculata, and we observed changes in growth and reproduction in response to predation risk from a caged predator (Trachemys scripta elegans. P. canaliculata produced eggs earlier in the presence of predators and injured conspecifics compared with the control group (no risk, although the total number of egg masses laid by per female was exceeded by that of the controls after 15 days. Egg hatching success noticeably decreased under predation risk, and the incubation period was significantly prolonged; however, the oviposition height of the snails was not affected. A lethal effect of predation risk was detected in juvenile snails but not in adults. The growth of juvenile P. canaliculata was inhibited under predation risk, probably due to a reduction in food intake. Adult females exhibited a greater reduction in growth under predation risk than males, which likely resulted in part from the high reproductive investment of females in egg laying. These results indicate that P. canaliculata snails under predation risk face a trade-off between predator avoidance and growth and reproduction, where the lethal effect of predation risk is linked to the size of the prey.

  18. Exponential growth for self-reproduction in a catalytic reaction network: relevance of a minority molecular species and crowdedness

    Science.gov (United States)

    Kamimura, Atsushi; Kaneko, Kunihiko

    2018-03-01

    Explanation of exponential growth in self-reproduction is an important step toward elucidation of the origins of life because optimization of the growth potential across rounds of selection is necessary for Darwinian evolution. To produce another copy with approximately the same composition, the exponential growth rates for all components have to be equal. How such balanced growth is achieved, however, is not a trivial question, because this kind of growth requires orchestrated replication of the components in stochastic and nonlinear catalytic reactions. By considering a mutually catalyzing reaction in two- and three-dimensional lattices, as represented by a cellular automaton model, we show that self-reproduction with exponential growth is possible only when the replication and degradation of one molecular species is much slower than those of the others, i.e., when there is a minority molecule. Here, the synergetic effect of molecular discreteness and crowding is necessary to produce the exponential growth. Otherwise, the growth curves show superexponential growth because of nonlinearity of the catalytic reactions or subexponential growth due to replication inhibition by overcrowding of molecules. Our study emphasizes that the minority molecular species in a catalytic reaction network is necessary for exponential growth at the primitive stage of life.

  19. The impact of early life nutrition and housing on growth and reproduction in dairy cattle.

    Directory of Open Access Journals (Sweden)

    G Curtis

    Full Text Available Contentious issues in calf rearing include milk feeding practices and single versus group housing. The current study was performed on a high producing 170 Holstein cow dairy farm, to investigate the impact of nutrition and housing on growth and reproduction. Heifer calves (n = 100 were allocated in birth order to one of two commonly used management strategies. All calves received 3-4 litres of dam specific colostrum within 6 hours of birth. Group A calves were group housed from birth and fed milk replacer (MR ad libitum via a computerised machine utilising a single teat, with weaning commencing at 63 days of age. Group R calves were initially housed in individual pens and received 2.5 litres of MR twice daily via a bucket until 21 days of age when they were group housed and fed 3 litres of MR twice daily via a group trough with weaning commencing at 56 days. From 12 weeks of age onwards, calves in both dietary groups were subject to common nutritional and husbandry protocols. All breeding of heifers was via artificial insemination with no hormonal intervention. Calves were weighed, body condition scored and morphometric measures recorded weekly up till 12 weeks of age then monthly until conception. Pre-weaning growth rates (kg/day were significantly higher in Group A calves compared to Group R (0.89, 95% CI 0.86-0.93 vs 0.57, 95% CI 0.54-0.6 kg/day P 0.050 in any of the mean values of measured reproductive parameters, multivariable Cox regression suggested that there was a weak trend (P = 0.072 for Group A animals to achieve first service earlier than their Group R counterparts (62.6 weeks versus 65.3 weeks. Irrespective of dietary group, the hazard for achievement of all measured reproductive parameters, apart from time to puberty, was 20-40% less for heifers borne from multiparous dams compared to heifers from primiparous dams.

  20. The impact of early life nutrition and housing on growth and reproduction in dairy cattle.

    Science.gov (United States)

    Curtis, G; McGregor Argo, C; Jones, D; Grove-White, D

    2018-01-01

    Contentious issues in calf rearing include milk feeding practices and single versus group housing. The current study was performed on a high producing 170 Holstein cow dairy farm, to investigate the impact of nutrition and housing on growth and reproduction. Heifer calves (n = 100) were allocated in birth order to one of two commonly used management strategies. All calves received 3-4 litres of dam specific colostrum within 6 hours of birth. Group A calves were group housed from birth and fed milk replacer (MR) ad libitum via a computerised machine utilising a single teat, with weaning commencing at 63 days of age. Group R calves were initially housed in individual pens and received 2.5 litres of MR twice daily via a bucket until 21 days of age when they were group housed and fed 3 litres of MR twice daily via a group trough with weaning commencing at 56 days. From 12 weeks of age onwards, calves in both dietary groups were subject to common nutritional and husbandry protocols. All breeding of heifers was via artificial insemination with no hormonal intervention. Calves were weighed, body condition scored and morphometric measures recorded weekly up till 12 weeks of age then monthly until conception. Pre-weaning growth rates (kg/day) were significantly higher in Group A calves compared to Group R (0.89, 95% CI 0.86-0.93 vs 0.57, 95% CI 0.54-0.6 kg/day P 0.050) in any of the mean values of measured reproductive parameters, multivariable Cox regression suggested that there was a weak trend (P = 0.072) for Group A animals to achieve first service earlier than their Group R counterparts (62.6 weeks versus 65.3 weeks). Irrespective of dietary group, the hazard for achievement of all measured reproductive parameters, apart from time to puberty, was 20-40% less for heifers borne from multiparous dams compared to heifers from primiparous dams.

  1. Growth, survival and generative reproduction in a population of a widespread annual hemiparasite Melampyrum pratense

    Czech Academy of Sciences Publication Activity Database

    Průšová, M.; Lepš, Jan; Štěch, M.; Těšitel, J.

    2013-01-01

    Roč. 68, č. 1 (2013), s. 65-73 ISSN 0006-3088 Grant - others:AV ČR(CZ) IAA601410805; GA ČR(CZ) GAP505/12/1390; Grant Agency of the University of South Bohemia(CZ) 138/2010/P Institutional support: RVO:60077344 Keywords : demography * hemiparasitism * Melampyrum Subject RIV: ED - Physiology Impact factor: 0.696, year: 2013 http://link.springer.com/content/pdf/10.2478%2Fs11756-012-0130-x

  2. Growth, survival and bone alterations in Piaractus mesopotamicus larvae under different rearing protocols

    Directory of Open Access Journals (Sweden)

    David Roque Hernández

    2015-09-01

    Full Text Available The pacu (Piaractus mesopotamicus is a neotropical freshwater fish. It is one of the most important species farmed in areas of the Parana and Paraguay Rivers basins. The effects of different rearing protocols on growth, survival and incidence of skeletal malformations in pacu larvae were analyzed. A total of six experimental treatments were considered, consisting of: a semi-intensive larviculture (LS in ponds; intensive larviculture (LIn in laboratory (both LS and LIn until 60 days of life; and mixed larviculture, with 20 days of semi-intensive larviculture into cages in ponds after 14 (L1, 21 (L2, 33 (L3 or 40 (L4 days of laboratory larviculture. At the end of the experimental period, LSlarvae showed higher growth rate, with average weight values (2.28g and total length (TL-48.20mm statistically higher than the rest (P1 to L4 treatments showed intermediate growth values, without differences between them (P>0.05, while LIn presented the lowest growth (PS, that presented a significantly lower value (17.5%, PIn and L1 presented the lowest incidence. In no case, visible morphological alterations were found. This study shows that prolonging pacu rearing under laboratory conditions at high densities improves temporal availability and survival of juvenile without affecting growth or subsequent osteological development of fish.

  3. Growth and Survival of Bagged Lucilia sericata Maggots in Wounds of Patients Undergoing Maggot Debridement Therapy

    OpenAIRE

    Čičková, Helena; Čambal, Marek; Kozánek, Milan; Takáč, Peter

    2013-01-01

    Maggot debridement therapy (MDT) is an established method of debridement of nonhealing wounds. Despite intense clinical research about its efficacy and effects of substances produced by the larvae, growth and development of maggots in the wounds remain largely unexplored. In the present study, the bags with larvae (n = 52), which had been used to debride traumatic, ischemic, diabetic and venous ulcers, were collected and examined. Survival, length, width and larval instar of the maggots withi...

  4. Micro wholesaling businesses involved in the sector of confectionary products - strategies of survival and growth

    OpenAIRE

    Raptopoulos, PS

    2011-01-01

    It can be argued that the problematic situation where micro Greek wholesaling businesses find themselves has been a result of the strong presence of supermarkets and superstores in the last years. The researcher attempts to picture the current market reality that constitutes the background of the Thesis by posing the main research question: "How can micro Greek wholesaling businesses involved in the confectionary products' sector identify and implement suitable survival and growth strategies ...

  5. Comparisons of Growth and Survival Performance Among Selected Families and Wild Populations of Fenneropenaeus chinensis

    Science.gov (United States)

    Luo, Kun; Kong, Jie; Meng, Xianhong; Luan, Sheng; Cao, Baoxiang; Chen, Baolong

    2018-04-01

    In this study, families of selected population for growth (SP_BWT), selected population for white spot syndrome virus (WSSV) resistance (SP_RW), Bohai wild population (WP_BH) and Huanghai wild population (WP_HH) of F. chinensis were constructed through artificial insemination and with the standardized procedure of larvae rearing. Growth and survival performance were studied among four populations after a 70 days common test. The results showed that the maximum least square mean of body weight was 17.50 g in SP_BWT while the minimum was 13.03 g in WP_HH. Compared with WP_BH, body weight of SP_BWT increased by 23.41% ( P 0.05). Body weights of SP_BWT and SP_RW were significantly higher than that of WP_HH, which increased by 34.31% ( P populations was 0.19, 0.18, 0.17 and 0.16 g d-1, respectively. Coefficient of variation of body weight among four populations was high, which ranged from 32.67% to 35.25%. Such a range showed that there was the potentiality for further improvement in selected populations. Coefficient of variation of survival rate among four populations was low, varying between 3.20% and 5.90%. The difference of survival was highly significant ( P populations ( P growth performances were also observed among different families in each population. The body weight of 798F family was the highest. The absolute growth rate (AGR) was 0.25 g d-1, 150% higher than that of the lowest one, 0.1 g d-1 in 807F family. Survival rate of families among four populations was different. The highest was 94.74%, and the lowest was 71.88%.

  6. Early survival and growth of planted Douglas-fir with red alder in four mixed regimes.

    Science.gov (United States)

    Marshall D. Murray; Richard E. Miller

    1986-01-01

    To quantify between-species interactions, we measured and compared survival and growth of planted Douglas-fir and associated planted and volunteer red alder at a location on the west side of the Cascade Range in Washington. The planted alder were wildlings dug either from a nearby area or from a distant, coastal site and interplanted into a 3-year-old Douglas-fir...

  7. The effects of grading on the growth and survival of juvenile Dover sole (Solea solea L)

    DEFF Research Database (Denmark)

    Overton, Julia Lynne; Steenfeldt, Svend Jørgen; Pedersen, Per Bovbjerg

    2010-01-01

    A 3-month study was carried out to investigate the effects of grading on the overall production, growth performance and survival of juvenile Dover sole (Solea solea L.). Juvenile fish (4.0–40.4 g) were sorted into three size groups: small (4.0–15.5 g), medium (16.0–21.5 g) and large (22.0–40.5 g)...

  8. Adaptation, growth and survival of tilapia (Oreochromis niloticus) in Bafgh brackish water

    OpenAIRE

    Sarsangi, A.H.; Mohammadi, M.; Mashaii, N.; Rajabipou, F.; Bitaraf, A.; Askari, H.M.; Moazedi, J.; Nezamabadi, H.; Hosseinzadeh Sahafi, H.

    2012-01-01

    An experiment was conducted to evaluate the possibility of adaptation, growth and survival of Nile tilapia (Oreochromis niloticus) with 0.3g initial weight and red tilapia (Oreochromis sp.) with 0.7g initial weight in underground brackish water. Fry of Nile tilapia and red tilapia imported from Indonesia and after passing larviculture (25g) were examined separately in fiber glass tank by two replicate. Fish were fed at a restricted feeding program according to standard table during the light ...

  9. A trade-off between reproduction and feather growth in the barn swallow (Hirundo rustica.

    Directory of Open Access Journals (Sweden)

    Nicola Saino

    Full Text Available Physiological trade-offs mediated by limiting energy, resources or time constrain the simultaneous expression of major functions and can lead to the evolution of temporal separation between demanding activities. In birds, plumage renewal is a demanding activity, which accomplishes fundamental functions, such as allowing thermal insulation, aerodynamics and socio-sexual signaling. Feather renewal is a very expensive and disabling process, and molt is often partitioned from breeding and migration. However, trade-offs between feather renewal and breeding have been only sparsely studied. In barn swallows (Hirundo rustica breeding in Italy and undergoing molt during wintering in sub-Saharan Africa, we studied this trade-off by removing a tail feather from a large sample of individuals and analyzing growth bar width, reflecting feather growth rate, and length of the growing replacement feather in relation to the stage in the breeding cycle at removal and clutch size. Growth bar width of females and length of the growing replacement feather of both sexes were smaller when the original feather had been removed after clutch initiation. Importantly, in females both growth bar width and replacement feather length were negatively predicted by clutch size, and more strongly so for large clutches and when feather removal occurred immediately after clutch completion. Hence, we found strong, coherent evidence for a trade-off between reproduction, and laying effort in particular, and the ability to generate new feathers. These results support the hypothesis that the derived condition of molting during wintering in long-distance migrants is maintained by the costs of overlapping breeding and molt.

  10. Review of factors affecting the growth and survival of follicular grafts

    Directory of Open Access Journals (Sweden)

    William M Parsley

    2010-01-01

    Full Text Available Great strides have been made in hair restoration over the past 20 years. A better understanding of natural balding and non-balding patterns along with more respect for ageing has helped guide proper hairline design. Additionally, the use of smaller grafts has created a significantly improved natural appearance to the transplanted grafts. Inconsistent growth and survival of follicular grafts, however, has continued to be a problem that has perplexed hair restoration surgeons. This review attempts to explore the stresses affecting grafts during transplantation and some of the complexities involved in graft growth and survival. These authors reviewed the literature to determine the primary scope of aspects influencing growth and survival of follicular grafts. This scope includes patient selection, operating techniques, graft care, storage solutions and additives. The primary focus of the hair restoration surgeons should first be attention to the fundamentals of hair care, hydration, temperature, time out of body and gentle handling. Factors such as advanced storage solutions and additives can be helpful once the fundamentals have been addressed.

  11. Effects of symbiotic bacteria and tree chemistry on the growth and reproduction of bark beetle fungal symbionts

    Science.gov (United States)

    A.S. Adams; C.R. Currie; Y. Cardoza; K.D. Klepzig; K.F. Raffa

    2009-01-01

    Bark beetles are associated with diverse assemblages of microorganisms, many of which affect their interactions with host plants and natural enemies. We tested how bacterial associates of three bark beetles with various types of host relationships affect growth and reproduction of their symbiotic fungi. Fungi were exposed to volatiles...

  12. Dietary effects on growth, reproduction, body composition and stress resistance in the terrestrial isopods Oniscus asellus and Porcellio scaber.

    NARCIS (Netherlands)

    Lavy, D.; van Rijn, M.J.; Zoomer, H.R.; Verhoef, H.A.

    2001-01-01

    The effect of differences in food composition on growth, body composition and cold tolerance of the isopods Porcellio scaber (Latreille) and Oniscus asellus (L.) has been studied. The effect on reproduction of P. scaber was included. Total lipid and protein content remained the same in O. asellus,

  13. Fisheries-induced evolution in growth, maturation and reproductive investment of the sexually dimorphic North Sea plaice (Pleuronectes platessa L.)

    NARCIS (Netherlands)

    van Walraven, L.; Mollet, F. M.; van Damme, C. J. G.; Rijnsdorp, A. D.

    2010-01-01

    Changes in the onset of sexual maturation, reproductive investment and growth of North Sea plaice are studied between three periods: 1900s, 1980s and 2000s. Probabilistic maturation reaction norms of both males and females, describing the probability of becoming mature conditional on age and size,

  14. The effect of isolation on reproduction and growth of Pseudosuccinea columella (Pulmonata: Lymnaeidae: a snail-conditioned water experiment

    Directory of Open Access Journals (Sweden)

    Gutiérrez Alfredo

    2002-01-01

    Full Text Available A snail-conditioned water experiment was conducted in Pseudosuccinea columella to test the possible role of a chemical interaction between snails on the diminished growth and fecundity rates found for snails raised in pairs compared to those raised in complete isolation. The results permit to discard the hypothesis of an inhibition of growth and reproduction between snails due to factors released into the water.

  15. Effects of continuous ivermectin treatment from birth to puberty on growth and reproduction in dairy heifers.

    Science.gov (United States)

    Mejía, M; Gonzalez-Iglesias, A; Díaz-Torga, G S; Villafañe, P; Formía, N; Libertun, C; Becú-Villalobos, D; Lacau-Mengido, I M

    1999-06-01

    The effect of continuous ivermectin treatment from birth to puberty on growth and reproductive performance was studied in Holstein heifer calves grown on pastures in comparison to naturally nematode-infected, untreated animals. Ivermectin effectively abated the presence of nematode eggs in feces. Eggs per gram (EPG) in parasitized animals increased rapidly from wk 12 to 18 of age and then decreased. Animals treated with ivermectin grew faster than untreated ones, and differences in body weight became significant at 6 wk of life, even before eggs appeared in the feces of either treatment group. Ivermectin-treated heifers reached puberty 3 wk earlier than infected ones as assessed with serum progesterone concentrations (ivermectin, 30.4 +/- .8 vs untreated, 33.7 +/- 1.3 wk of age). This delay was not directly related to body weight. In addition, pelvic area at 39 wk and at 15 mo of age was increased in treated heifers (8 and 11%, respectively) compared with parasitized animals. No differences in the wither heights were observed. We conclude that ivermectin treatment in dairy heifers may increase growth rate during development, advance the onset of ovarian function, and positively affect yearling pelvic area.

  16. Growth and reproductive performance of sambar deer in Sabal Forest Reserve of Sarawak, Malaysia.

    Science.gov (United States)

    Dahlan, Ismail; Dawend, Jiwan

    2013-10-01

    We examined the growth, reproduction, rutting behavior, and health status of sambar deer (Cervus unicolor brookei) in secondary Acacia mangium plantation. The data were collected over 11 years from a breeding herd of 21 stags and 33 hinds in Sabal Forest Reserve, Sarawak, Malaysia. Brody's growth model of the pooled data is Y t  = 148.56 (1 - 0.98e(-0.023t)), which estimates that maximum weights of adults are 184 and 115 kg for males and females respectively. Sambar deer are nonseasonal breeders with the breeding peak in February. Although the earliest age at which a female reached sexual maturity was 11 months, the mean age was 23 ± 7 months. Mean age of first fawning was 32 ± 8 months. Mean gestation period was 259 ± 12 days (n = 82). Stags shed antlers mostly between March and July. Velvet hardens at 103 ± 27 days (n = 23), and velvet harvesting is best at 7-9 weeks when antler length is 25-30 cm. Sambar deer are suitable as a farm species in forest plantations and have a vast potential to uplift rural living standards.

  17. Infection of growing swine with porcine reproductive and respiratory syndrome virus and Mycoplasma hyopneumoniae — Effects on growth, serum metabolites, and insulin-like growth factor-I.

    OpenAIRE

    Roberts, N. Elizabeth; Almond, Glen W.

    2003-01-01

    This study evaluated the influence of concomitant infections with porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae on growth performance, serum metabolite concentrations, and serum insulin-like growth factor-I (IGF-I) in growing pigs. Twenty-two barrows (10 weeks of age) were treated with either an intranasal administration of PRRSV and an intratracheal infusion of M. hyopneumoniae (treatment; n = 8) or a sham inoculation with medium (sham; n = 8), or w...

  18. Growth promotion and inhibition of the Amazonian wild rice species Oryza grandiglumis to survive flooding.

    Science.gov (United States)

    Okishio, Takuma; Sasayama, Daisuke; Hirano, Tatsuya; Akimoto, Masahiro; Itoh, Kazuyuki; Azuma, Tetsushi

    2014-09-01

    In Asian cultivated rice (Oryza sativa), distinct mechanisms to survive flooding are activated in two groups of varieties. Submergence-tolerant rice varieties possessing the SUBMERGENCE1A (SUB1A) gene display reduced growth during flash floods at the seedling stage and resume growth after the flood recedes, whereas deepwater rice varieties possessing the SNORKEL1 (SK1) and SNORKEL2 (SK2) genes display enhanced growth based on internodal elongation during prolonged submergence at the mature stage. In this study, we investigated the occurrence of these growth responses to submergence in the wild rice species Oryza grandiglumis, which is native to the Amazon floodplains. When subjected to gradual submergence, adult plants of O. grandiglumis accessions showed enhanced internodal elongation with rising water level and their growth response closely resembled that of deepwater varieties of O. sativa with high floating capacity. On the other hand, when subjected to complete submergence, seedlings of O. grandiglumis accessions displayed reduced shoot growth and resumed normal growth after desubmergence, similar to the response of submergence-tolerant varieties of O. sativa. Neither SUB1A nor the SK genes were detected in the O. grandiglumis accessions. These results indicate that the O. grandiglumis accessions are capable of adapting successfully to flooding by activating two contrasting mechanisms as the situation demands and that each mechanism of adaptation to flooding is not mediated by SUB1A or the SK genes.

  19. Effect of diet supplementation on growth and reproduction in camels under arid range conditions

    Directory of Open Access Journals (Sweden)

    Abdouli H.

    2001-01-01

    Full Text Available Eighteen pregnant dromedary females (Camelus dromedarius were used to determine the effect of concentrate supplement on growth and reproductive performances in peri-partum period. The females were divided into supplemented (n = 9; S and unsupplemented (n = 9; C experimental groups. All animals grazed, with one mature male, 7 to 8 hours per day on salty pasture rangelands. During night, they were kept in pen, where each female of group S received 4 kg per day of concentrate supplement during the last 3 months of gestation and 5 kg per day during the first 3 months post-partum. During the last 90 days of gestation daily body weight gain (DBG was at least tenfold more important in group S than in group C (775 g vs. 72 g respectively. Supplementation affected birth weight of offspring (30.3 kg vs. 23.4 kg and its DBG (806 g vs. 430 g in group S and group C respectively. During the post-partum period, females in group S gained in weight (116 g per day whereas females in group C lost more than 200 g per day. The mean post-partum interval to the first heat and the percentage of females in heat were 29.5 day and 44.4/ vs. 41.2 day and 71.4/ for the C and S groups, respectively. We conclude that under range conditions, dietary supplementation of dromedary during late pregnancy stage and post-partum period improves productive and reproductive parameters.

  20. Impacts of Bokashi on survival and growth rates of Pinus pseudostrobus in community reforestation projects.

    Science.gov (United States)

    Jaramillo-López, P F; Ramírez, M I; Pérez-Salicrup, D R

    2015-03-01

    Community-based small-scale reforestation practices have been proposed as an alternative to low-efficiency massive reforestations conducted by external agents. These latter conventional reforestations are often carried out in soils that have been seriously degraded and this has indirectly contributed to the introduction of non-native species and/or acceptance of very low seedling survival rates. Bokashi is a fermented soil organic amendment that can be made from almost any available agricultural byproduct, and its beneficial effects in agriculture have been reported in various contexts. Here, we report the results of a community-based small-scale experimental reforestation where the provenance of pine seedlings (local and commercial) and the use of Bokashi as a soil amendment were evaluated. Bokashi was prepared locally by members of a small rural community in central Mexico. Almost two years after the establishment of the trial, survival rates for the unamended and amended local trees were 97-100% while survival of the commercial trees from unamended and amended treatments were 87-93%. Consistently through time, local and commercial seedlings planted in Bokashi-amended soils were significantly taller (x̅ = 152 cm) than those planted in unamended soils (̅x = 86 cm). An unplanned infection by Cronartium quercuum in the first year of the experiment was considered as a covariable. Infected seedlings showed malformations but this did not affect survival and growth rates. Bokashi amendment seems as an inexpensive, locally viable technology to increase seedling survival and growth and to help recover deforested areas where soils have been degraded. This allows local stakeholders to see more rapid results while helping them to maintain their interest in conservation activities. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. The Effect of Various Species of Macroalgae on the Growth, Survival, and Toxicity of Karenia brevis

    Science.gov (United States)

    Gardner, K. G.; Lovko, V. J.; Henry, M. S.

    2016-02-01

    Harmful algal blooms (HABs) caused by the dinoflagellate Karenia brevis produce toxins that result in negative impacts to both humans and the environment. Little is known about the termination stages of these blooms, and few viable control mechanisms have been suggested. Natural, algae derived compounds have been proposed as a way to limit bloom growth and reduce brevetoxins in the water column. The work presented here examines the ability of macroalgae to inhibit the growth or survival of K. brevis, similar to what has been demonstrated with other red tide species. Additionally, we attempted to determine if macroalgae decreases water column brevetoxins which, to our knowledge, has not been tested with macroalgae but has been demonstrated in other studies with microalgal species. The macroalgae species Dictyota sp. and Gracilaria sp. caused 100% mortality of K. brevis in under 24 hours. Compared to the control, 7 other species significantly decreased the growth rate of K. brevis. The Dictyota treatments showed significant toxin reduction and increase of the antitoxin brevanol. These results indicate that some combination of compounds produced by macroalgae inhibit growth and survival of K. brevis and possibly limit their toxin production. Future studies will attempt to isolate and identify these compounds and test their effects on other marine organisms such as diatoms. Determining the interactions between HAB species K. brevis and macroalgal species will provide insights on the mechanism of bloom termination and a potential control method.

  2. Females increase reproductive investment in response to helper-mediated improvements in allo-feeding, nest survival, nestling provisioning and post-fledging survival in the Karoo scrub-robin Cercotrichas coryphaeus

    Science.gov (United States)

    Lloyd, P.; Andrew, Taylor W.; du Plessis, Morné A.; Martin, T.E.

    2009-01-01

    In many cooperatively-breeding species, the presence of one or more helpers improves the reproductive performance of the breeding pair receiving help. Helper contributions can take many different forms, including allo-feeding, offspring provisioning, and offspring guarding or defence. Yet, most studies have focussed on single forms of helper contribution, particularly offspring provisioning, and few have evaluated the relative importance of a broader range of helper contributions to group reproductive performance. We examined helper contributions to multiple components of breeding performance in the Karoo scrub-robin Cercotrichas coryphaeus, a facultative cooperative breeder. We also tested a prediction of increased female investment in reproduction when helpers improve conditions for rearing young. Helpers assisted the breeding male in allo-feeding the incubating female, increasing allo-feeding rates. Greater allo-feeding correlated with greater female nest attentiveness during incubation. Nest predation was substantially lower among pairs breeding with a helper, resulting in a 74% increase in the probability of nest survival. Helper contributions to offspring provisioning increased nestling feeding rates, resulting in a reduced incidence of nestling starvation and increased nestling mass. Nestling mass had a strong, positive effect on post-fledging survival. Controlling for female age and habitat effects, annual production of fledged young was 130% greater among pairs breeding with a helper, and was influenced most strongly by helper correlates with nest survival, despite important helper effects on offspring provisioning. Females breeding with a helper increased clutch size, supporting the prediction of increased female investment in reproduction in response to helper benefits. ?? 2009 J. Avian Biol.

  3. THE EFFECT OF FEEDING Lactobacillus ON GROWTH, SURVIVAL RATE AND PROTEASE ACTIVITY OF Litopenaeus vannamei

    Directory of Open Access Journals (Sweden)

    Nunak Nafiqoh

    2011-12-01

    Full Text Available This study examined the effect of two Lactobacillus bacteria on protease activity and growth rate of Litopenaeus vannamei. An experiment was conducted to examine protease activity and growth rate. The experiment consisted of two treatment tanks, the first tank was provided with artemia immersed in 2.6 x 1016 cfu/mL of bacteria solution, the second tank served as the control tank. After 20 days, the L. vannamei in the tank that received Lactobacillus have significantly different in growth, survival rate and protease activity (P<0.05 compared to the control, but no significant difference between Lactobacillus casei and Lactobacillus plantarum treatments. Within the digestive organ, protease activity of hepatopancreas and stomach demonstrated significant higher activity (P<0.05 compared to the intestine.

  4. Zcchc11 Uridylates Mature miRNAs to Enhance Neonatal IGF-1 Expression, Growth, and Survival

    Science.gov (United States)

    Kozlowski, Elyse; Matsuura, Kori Y.; Ferrari, Joseph D.; Morris, Samantha A.; Powers, John T.; Daley, George Q.; Quinton, Lee J.; Mizgerd, Joseph P.

    2012-01-01

    The Zcchc11 enzyme is implicated in microRNA (miRNA) regulation. It can uridylate let-7 precursors to decrease quantities of the mature miRNA in embryonic stem cell lines, suggested to mediate stem cell maintenance. It can uridylate mature miR-26 to relieve silencing activity without impacting miRNA content in cancer cell lines, suggested to mediate cytokine and growth factor expression. Broader roles of Zcchc11 in shaping or remodeling the miRNome or in directing biological or physiological processes remain entirely speculative. We generated Zcchc11-deficient mice to address these knowledge gaps. Zcchc11 deficiency had no impact on embryogenesis or fetal development, but it significantly decreased survival and growth immediately following birth, indicating a role for this enzyme in early postnatal fitness. Deep sequencing of small RNAs from neonatal livers revealed roles of this enzyme in miRNA sequence diversity. Zcchc11 deficiency diminished the lengths and terminal uridine frequencies for diverse mature miRNAs, but it had no influence on the quantities of any miRNAs. The expression of IGF-1, a liver-derived protein essential to early growth and survival, was enhanced by Zcchc11 expression in vitro, and miRNA silencing of IGF-1 was alleviated by uridylation events observed to be Zcchc11-dependent in the neonatal liver. In neonatal mice, Zcchc11 deficiency significantly decreased IGF-1 mRNA in the liver and IGF-1 protein in the blood. We conclude that the Zcchc11-mediated terminal uridylation of mature miRNAs is pervasive and physiologically significant, especially important in the neonatal period for fostering IGF-1 expression and enhancing postnatal growth and survival. We propose that the miRNA 3′ terminus is a regulatory node upon which multiple enzymes converge to direct silencing activity and tune gene expression. PMID:23209448

  5. Zcchc11 uridylates mature miRNAs to enhance neonatal IGF-1 expression, growth, and survival.

    Directory of Open Access Journals (Sweden)

    Matthew R Jones

    Full Text Available The Zcchc11 enzyme is implicated in microRNA (miRNA regulation. It can uridylate let-7 precursors to decrease quantities of the mature miRNA in embryonic stem cell lines, suggested to mediate stem cell maintenance. It can uridylate mature miR-26 to relieve silencing activity without impacting miRNA content in cancer cell lines, suggested to mediate cytokine and growth factor expression. Broader roles of Zcchc11 in shaping or remodeling the miRNome or in directing biological or physiological processes remain entirely speculative. We generated Zcchc11-deficient mice to address these knowledge gaps. Zcchc11 deficiency had no impact on embryogenesis or fetal development, but it significantly decreased survival and growth immediately following birth, indicating a role for this enzyme in early postnatal fitness. Deep sequencing of small RNAs from neonatal livers revealed roles of this enzyme in miRNA sequence diversity. Zcchc11 deficiency diminished the lengths and terminal uridine frequencies for diverse mature miRNAs, but it had no influence on the quantities of any miRNAs. The expression of IGF-1, a liver-derived protein essential to early growth and survival, was enhanced by Zcchc11 expression in vitro, and miRNA silencing of IGF-1 was alleviated by uridylation events observed to be Zcchc11-dependent in the neonatal liver. In neonatal mice, Zcchc11 deficiency significantly decreased IGF-1 mRNA in the liver and IGF-1 protein in the blood. We conclude that the Zcchc11-mediated terminal uridylation of mature miRNAs is pervasive and physiologically significant, especially important in the neonatal period for fostering IGF-1 expression and enhancing postnatal growth and survival. We propose that the miRNA 3' terminus is a regulatory node upon which multiple enzymes converge to direct silencing activity and tune gene expression.

  6. The dynamics of reproductive rate, offspring survivorship and growth in the lined seahorse, Hippocampus erectus Perry, 1810

    Science.gov (United States)

    Lin, Qiang; Li, Gang; Qin, Geng; Lin, Junda; Huang, Liangmin; Sun, Hushan; Feng, Peiyong

    2012-01-01

    Summary Seahorses are the vertebrate group with the embryonic development occurring within a special pouch in males. To understand the reproductive efficiency of the lined seahorse, Hippocampus erectus Perry, 1810 under controlled breeding experiments, we investigated the dynamics of reproductive rate, offspring survivorship and growth over births by the same male seahorses. The mean brood size of the 1-year old pairs in the 1st birth was 85.4±56.9 per brood, which was significantly smaller than that in the 6th birth (465.9±136.4 per brood) (Pseahorses H. erectus increased with the brood pouch development. PMID:23213429

  7. Water availability and population origin affect the expression of the tradeoff between reproduction and growth in Plantago coronopus

    DEFF Research Database (Denmark)

    Hansen, C. F.; Garcia, M. B.; Ehlers, B. K.

    2013-01-01

    temperature and precipitation. We found that water availability affected the expression of the tradeoff (both phenotypic and genetic) between reproduction and growth, being most accentuated under dry condition. However, populations responded very differently to water treatments. Plants from annual populations...... showed a similar response to drought condition with little variation among maternal families, suggesting a history of selection favouring genotypes with high allocation to reproduction when water availability is low. Plants from annual populations also expressed the highest level of plasticity...... water availability even among geographically close populations....

  8. Temperature affects brain and pituitary gene expression related to reproduction and growth in the male blue gouramis, Trichogaster trichopterus.

    Science.gov (United States)

    David, Dalia; Degani, Gad

    2011-04-01

    This study examined the effect of temperature on reproduction and growth-related factors in blue gourami males under nonreproductive and reproductive conditions. Males that were maintained under nonreproductive conditions did not build nest and the gonado-somatic index (% GSI) was significantly higher in fish maintained at 27°C compared with fish maintained at 23°C. The relative mRNA levels of brain gonadotropin-releasing hormone 3 (GnRH3), pituitary adenylate cyclase-activating polypeptide (PACAP), insulin-like growth factor-1(IGF-1), pituitary β-luteinizing hormone (βLH), and prolactin were significantly higher when the fish were maintained at 27°C than at 23°C or 31°C. β-Follicle-stimulating hormone (βFSH) mRNA levels were significantly lower when maintained at 31°C than at the other temperatures. Nests were observed only in males under reproductive conditions. In these fish, higher mRNA levels of GnRH3, PACAP, βFSH, βLH and prolactin were detected at 27°C, and higher mRNA levels of IGF-1 were detected at 23°C, when compared with other temperature of maintenance or with fish that did not build nest. In conclusion, we propose that temperature has more effect on the transcription of genes, associated with reproduction, than on those pertaining to growth. Copyright © 2011 Wiley-Liss, Inc., A Wiley Company.

  9. Density dependence and phenological mismatch: consequences for growth and survival of sub-arctic nesting Canada Geese

    Directory of Open Access Journals (Sweden)

    Rodney W. Brook

    2015-06-01

    Full Text Available The extent to which species are plastic in the timing of their reproductive events relative to phenology suggests how climate change might affect their demography. An ecological mismatch between the timing of hatch for avian species and the peak availability in quality and quantity of forage for rapidly growing offspring might ultimately affect recruitment to the breeding population unless individuals can adjust the timing of breeding to adapt to changing phenology. We evaluated effects of goose density, hatch timing relative to forage plant phenology, and weather indices on annual growth of pre-fledging Canada geese (Branta canadensis from 1993-2010 at Akimiski Island, Nunavut. We found effects of both density and hatch timing relative to forage plant phenology; the earlier that eggs hatched relative to forage plant phenology, the larger the mean gosling size near fledging. Goslings were smallest in years when hatch was latest relative to forage plant phenology, and when local abundance of breeding adults was highest. We found no evidence for a trend in relative hatch timing, but it was apparent that in early springs, Canada geese tended to hatch later relative to vegetation phenology, suggesting that geese were not always able to adjust the timing of nesting as rapidly as vegetation phenology was advanced. Analyses using forage biomass information revealed a positive relationship between gosling size and per capita biomass availability, suggesting a causal mechanism for the density effect. The effects of weather parameters explained additional variation in mean annual gosling size, although total June and July rainfall had a small additive effect on gosling size. Modelling of annual first-year survival probability using mean annual gosling size as an annual covariate revealed a positive relationship, suggesting that reduced gosling growth negatively impacts recruitment.

  10. Density dependence and phenological mismatch: consequences for growth and survival of sub-arctic nesting Canada Geese

    Science.gov (United States)

    Brook, Rodney W.; Leafloor, James O.; Douglas, David C.; Abraham, Kenneth F.

    2015-01-01

    The extent to which species are plastic in the timing of their reproductive events relative to phenology suggests how change might affect their demography. An ecological mismatch between the timing of hatch for avian species and the peak availability in quality and quantity of forage for rapidly growing offspring might ultimately affect recruitment to the breeding population unless individuals can adjust the timing of breeding to adapt to changing phenology. We evaluated effects of goose density, hatch timing relative to forage plant phenology, and weather indices on annual growth of pre-fledging Canada geese (Branta canadensis) from 1993-2010 at Akimiski Island, Nunavut. We found effects of both density and hatch timing relative to forage plant phenology; the earlier that eggs hatched relative to forage plant phenology, the larger the mean gosling size near fledging. Goslings were smallest in years when hatch was latest relative to forage plant phenology, and when local abundance of breeding adults was highest. We found no evidence for a trend in relative hatch timing, but it was apparent that in early springs, Canada geese tended to hatch later relative to vegetation phenology, suggesting that geese were not always able to adjust the timing of nesting as rapidly as vegetation phenology was advanced. Analyses using forage biomass information revealed a positive relationship between gosling size and per capita biomass availability, suggesting a causal mechanism for the density effect. The effects of weather parameters explained additional variation in mean annual gosling size, although total June and July rainfall had a small additive effect on gosling size. Modelling of annual first year survival probability using mean annual gosling size as an annual covariate revealed a positive relationship, suggesting that reduced gosling growth negatively impacts recruitment.

  11. Growth and Survival of Bagged Lucilia sericata Maggots in Wounds of Patients Undergoing Maggot Debridement Therapy

    Directory of Open Access Journals (Sweden)

    Helena Čičková

    2013-01-01

    Full Text Available Maggot debridement therapy (MDT is an established method of debridement of nonhealing wounds. Despite intense clinical research about its efficacy and effects of substances produced by the larvae, growth and development of maggots in the wounds remain largely unexplored. In the present study, the bags with larvae (n=52, which had been used to debride traumatic, ischemic, diabetic and venous ulcers, were collected and examined. Survival, length, width and larval instar of the maggots within each bag were recorded and analyzed with respect to the wound type and duration of the treatment. Survival of maggots after a 48-h cycle of MDT ranged between 63.6 and 82.7%. Maggots in venous ulcers had on average 9–19% higher mortality than maggots within traumatic, ischemic, and diabetic ulcers. Length of larvae after 48 h cycle of MDT reached on average 7.09–9.68 mm, and average width varied between 1.77 and 2.26 mm. Larvae in venous ulcers were significantly smaller after 48 h, but not after 72 h treatment compared to the other wound types. Further studies should be aimed to identify other patient-associated factors which might influence growth and survival of the larvae during maggot debridement therapy.

  12. Growth and Survival of Bagged Lucilia sericata Maggots in Wounds of Patients Undergoing Maggot Debridement Therapy.

    Science.gov (United States)

    Cičková, Helena; Cambal, Marek; Kozánek, Milan; Takáč, Peter

    2013-01-01

    Maggot debridement therapy (MDT) is an established method of debridement of nonhealing wounds. Despite intense clinical research about its efficacy and effects of substances produced by the larvae, growth and development of maggots in the wounds remain largely unexplored. In the present study, the bags with larvae (n = 52), which had been used to debride traumatic, ischemic, diabetic and venous ulcers, were collected and examined. Survival, length, width and larval instar of the maggots within each bag were recorded and analyzed with respect to the wound type and duration of the treatment. Survival of maggots after a 48-h cycle of MDT ranged between 63.6 and 82.7%. Maggots in venous ulcers had on average 9-19% higher mortality than maggots within traumatic, ischemic, and diabetic ulcers. Length of larvae after 48 h cycle of MDT reached on average 7.09-9.68 mm, and average width varied between 1.77 and 2.26 mm. Larvae in venous ulcers were significantly smaller after 48 h, but not after 72 h treatment compared to the other wound types. Further studies should be aimed to identify other patient-associated factors which might influence growth and survival of the larvae during maggot debridement therapy.

  13. Effects of Rearing Density on Survival, Growth, and Development of the Ladybird Coleomegilla maculata in Culture

    Directory of Open Access Journals (Sweden)

    Eric W. Riddick

    2015-10-01

    Full Text Available Our research focuses on developing techniques to rear ladybird beetles (Coleoptera: Coccinellidae. We evaluated the effects of rearing density on survival, growth, and development of Coleomegilla maculata. The hypothesis that a low to moderate rearing density has limited or no effects on survival and development was tested. C. maculata first instars were reared to pupae at a density of 1, 5, 10, 15, or 20 individuals per arena (2.5 cm high, 9.0 cm diameter, and 159 cm3 volume and fed powdered brine shrimp (Artemia franciscana eggs. More larvae survived at the 1 and 5 densities, but no differences were detected between the 10, 15, or 20 densities. Median survival rate was at least 90% for larvae and 100% for pupae at the 10, 15, and 20 densities. Development time, body weight, and sex ratio were unaffected by rearing density. Overall, this study suggests that C. maculata larvae can be reared successfully at a density of 20 larvae/159 cm3 (≈ 0.126 larvae/cm3 in containers provisioned with powdered A. franciscana eggs. Scaling-up the size of containers, and C. maculata density in these containers, should be possible.

  14. Effects of passive integrated transponder tags on survival and growth of juvenile Atlantic salmon Salmo salar

    DEFF Research Database (Denmark)

    Larsen, Martin Hage; Thorn, Aske N.; Skov, Christian

    2013-01-01

    Background: A laboratory experiment was conducted to assess the potential impacts of surgically implanted 23 and 32 mm passive integrated transponder (PIT) tags on survival, growth, and body condition of juvenile Atlantic salmon Salmo salar. Rate of tag retention and healing of the tagging incision...... were also evaluated. Atlantic salmon of three different size classes (I: 80 to 99 mm fork length (FL), II: 100 to 119 mm FL, III: 120 to 135 mm FL) were allocated to each of five experimental treatment groups: control, sham-operated (surgery without PIT-tag implantation), 23 mm PIT-tag implantation...... with and without suture closure of the incision, and 32 mm PIT-tag implantation without suture closure. Results: Over the 35-day experiment, mortality occurred only among fish tagged with 32 mm PIT tags (14%) and all fish larger than 103 mm FL survived. Non-sutured Atlantic salmon between 80 and 99 mm FL implanted...

  15. The regulation of function, growth and survival of GLP-1-producing L-cells

    DEFF Research Database (Denmark)

    Kuhre, Rune Ehrenreich; Holst, Jens Juul; Kappe, Camilla

    2016-01-01

    that regulate the growth, survival and function of these cells are largely unknown. We recently showed that prolonged exposure to high concentrations of the fatty acid palmitate induced lipotoxic effects, similar to those operative in insulin-producing cells, in an in vitro model of GLP-1-producing cells...... absorption and disposal, as well as cell proliferation and survival. In Type 2 Diabetes (T2D) reduced plasma levels of GLP-1 have been observed, and plasma levels of GLP-1, as well as reduced numbers of GLP-1 producing cells, have been correlated to obesity and insulin resistance. Increasing endogenous...... secretion of GLP-1 by selective targeting of the molecular mechanisms regulating secretion from the L-cell has been the focus of much recent research. An additional and promising strategy for enhancing endogenous secretion may be to increase the L-cell mass in the intestinal epithelium, but the mechanisms...

  16. The growth of Propionibacterium cyclohexanicum in fruit juices and its survival following elevated temperature treatments.

    Science.gov (United States)

    Walker, Michelle; Phillips, Carol A

    2007-06-01

    This study investigated the growth of Propionibacterium cyclohexanicum in orange juice over a temperature range from 4 to 40 degrees C and its ability to multiply in tomato, grapefruit, apple, pineapple and cranberry juices at 30 and 35 degrees C. Survival after 10 min exposure to 50, 60, 70, 80, 85, 90 and 95 degrees C in culture medium and in orange juice was also assessed. In orange juice the organism was able to multiply by 2 logs at temperatures from 4 to 35 degrees C and survived for up to 52 days. However, at 40 degrees C viable counts were reduced after 6 days and no viable cells isolated after 17 days. The optimum growth temperature in orange juice over 6 days was 25 degrees C but over 4 days it was 35 degrees C. The growth of P. cyclohexanicum was monitored in tomato, grapefruit, cranberry, pineapple and apple juices at 30 and 35 degrees C over 29 days. Cranberry, grapefruit and apple juice did not support the growth of P. cyclohexanicum. At 30 degrees C no viable cells were detected after 8 days in cranberry juice or after 22 days in grapefruit juice while at 35 degrees C no viable cells were detected after 5 and 15 days, respectively. However, in apple juice, although a 5 log reduction occurred, viable cells could be detected after 29 days. P. cyclohexanicum was able to multiply in both tomato and pineapple juices. In tomato juice, there was a 2 log increase in viable counts after 8 days at 30 degrees C but no increase at 35 degrees C, while in pineapple juice there was a 1 log increase in numbers over 29 days with no significant difference between numbers of viable cells present at 30 and 35 degrees C. The organism survived at 50 degrees C for 10 min in culture medium without a significant loss of viability while similar treatment at 60, 70 and 80 degrees C resulted in approximately a 3-4 log reduction, with no viable cells detected after treatment at 85 or 90 or 95 degrees C but, when pre-treated at intermediate temperatures before exposure to higher

  17. Reproductive death and population kinetics in survival fractions of in vitro hamster cells during 48 hours after X-irradiation with doses up to 800 Rds. Pt. 2

    International Nuclear Information System (INIS)

    Hagemann, G.

    1976-01-01

    By means of a quantitative analysis, the time dependency of the number of dead cells and the resulting statement of cell numbers are compared with colony survival curves and with the distribution of colony sizes. The obtained periodical variation of reproductively killed cells is analyzed through population kinetics and is reduced to the number of those among the irradiated cells which show radiation-induced lethal reproductive damage. Therefrom, together with both sorts of interphase-dead cells, the dose dependency of the three lethal fractions results, taking into consideration the quantitative cellular statement. The formation of maxima of reproductively killed cells at the intervals of generation time until F 3 -generation is explained by an autosynchronization of partly lethally injured cell populations. From colony size distributions a linear dose dependency of the mean colony size group can be derived; this is discussed in connection with DNA double strand breaks regarded as a possible cause of reproductive lethal damages. The data obtained concerning the development of a cell population with radiation damages are evaluated by the construction of phylogenetic schedules for every 300 rd and 500 rd. By this means, the underlying population kinetics is being revised quantitatively. (orig.) [de

  18. Effect of temperature on growth, survival and respiratory rate of larval allis shad Alosa alosa

    Directory of Open Access Journals (Sweden)

    Hundt M.

    2015-01-01

    Full Text Available Prior species distribution models identified temperature as one of the most important environmental variables defining the present and future distribution of anadromous allis shad (Alosa alosa. The current study analysed effects of temperature on the recruitment-potential of allis shad by investigating growth and survival at 16, 20, 24 and 28 °C during a ten day rearing trial and by measuring mass-specific respiration. Highest growth in length was at 28 °C; growth at 16 °C was minimal. At the end of the rearing-period, no significant differences in survival between tested rearing-temperatures were found. Exposure to temperatures of 13 to 30 °C and subsequent measurement of mass-specific respiration revealed tolerance of temperatures up to 30 °C and a lower temperature limitation close to 16 °C. After acclimatization of larvae to temperatures ranging from 16−28 °C for 10 days, Q10-values of mass-specific respiration indicated a high adaptive capacity to increasing temperatures, but also the ability to adapt to temperatures as low as 16 °C. Our results indicate that the predicted temperature sensitivity of A. alosa cannot be explained by a direct physiological relationship. The obtained results can help to improve predictive modelling and the conservation of allis shad throughout its current distribution range.

  19. Effects of UV-B irradiation on growth, survival, pigmentation and nitrogen metabolism enzymes in Cyanobacteria

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, R.P.; Hader, D.P. [Institut fuer Botanik und Pharmazeutische Biologie, Friedrich-Alexander Universitaet, Erlangen (Germany); Kumar, H.D.; Kumar, A. [Banaras Hindu University, Varanasi (India)

    1995-12-31

    The effects of artificial UV-B irradiation on growth, survival, pigmentation, nitrate reductase (NR), glutamine synthetase (GS) and total protein profile have been studied in a number of N{sub 2}-fixing cyanobacterial strains isolated from rice (paddy) fields in India. Different organisms show different effects in terms of growth and survival. Complete killing of Anabaena sp. and Nostoc carmium occurs after 120 min of UV-B exposure, whereas the same occurs only after 150 min of exposure in the case of Nostoc commune and Scytonema sp. Growth patterns of the cells treated with UV-B revealed that Nostoc commune and Scytonema sp. are comparatively more tolerant than Anabaena sp. and Nostoc carmium. Pigment content, particularly phycocyanin, was severely decreased following UV-B irradiation in all strains tested so far. In vivo NR activity was found to increase, while in vivo GS activity was decreased following exposure to UV-B for different durations in all test organisms; although complete inhibition of GS activity did not occur even after 120 min of UV-B exposure. (author). 37 refs, 6 figs.

  20. Effects of UV-B irradiation on growth, survival, pigmentation and nitrogen metabolism enzymes in Cyanobacteria

    International Nuclear Information System (INIS)

    Sinha, R.P.; Hader, D.P.; Kumar, H.D.; Kumar, A.

    1995-01-01

    The effects of artificial UV-B irradiation on growth, survival, pigmentation, nitrate reductase (NR), glutamine synthetase (GS) and total protein profile have been studied in a number of N 2 -fixing cyanobacterial strains isolated from rice (paddy) fields in India. Different organisms show different effects in terms of growth and survival. Complete killing of Anabaena sp. and Nostoc carmium occurs after 120 min of UV-B exposure, whereas the same occurs only after 150 min of exposure in the case of Nostoc commune and Scytonema sp. Growth patterns of the cells treated with UV-B revealed that Nostoc commune and Scytonema sp. are comparatively more tolerant than Anabaena sp. and Nostoc carmium. Pigment content, particularly phycocyanin, was severely decreased following UV-B irradiation in all strains tested so far. In vivo NR activity was found to increase, while in vivo GS activity was decreased following exposure to UV-B for different durations in all test organisms; although complete inhibition of GS activity did not occur even after 120 min of UV-B exposure. (author)

  1. glpx Gene in Mycobacterium tuberculosis Is Required for In Vitro Gluconeogenic Growth and In Vivo Survival.

    Directory of Open Access Journals (Sweden)

    Hiten J Gutka

    Full Text Available Several enzymes involved in central carbon metabolism and gluconeogenesis play a critical role in survival and pathogenesis of Mycobacterium tuberculosis (Mtb. The only known functional fructose 1,6-bisphosphatase (FBPase in Mtb is encoded by the glpX gene and belongs to the Class II sub-family of FBPase. We describe herein the generation of a ΔglpX strain using homologous recombination. Although the growth profile of ΔglpX is comparable to that of wild type Mtb when grown on the standard enrichment media, its growth is dysgonic with individual gluconeogenic substrates such as oleic acid, glycerol and acetate. In mice lung CFU titers of ΔglpX were 2-3 log10 lower than the wild-type Mtb strain. The results indicate that glpX gene encodes a functional FBPase and is essential for both in vitro and in vivo growth and survival of Mtb. Loss of glpX results in significant reduction of FBPase activity but not complete abolition. These findings verify that the glpX encoded FBPase II in Mtb can be a potential target for drug discovery.

  2. The growth and survival of plants in urban green roofs in a dry climate.

    Science.gov (United States)

    Razzaghmanesh, M; Beecham, S; Kazemi, F

    2014-04-01

    Green roofs as one of the components of water-sensitive urban design have become widely used in recent years. This paper describes performance monitoring of four prototype-scale experimental green roofs in a northern suburb of Adelaide, South Australia, undertaken over a 1-year period. Four species of indigenous Australian ground cover and grass species comprising Carpobrotus rossii, Lomandra longifolia 'Tanika,' Dianella caerula 'Breeze' and Myoporum parvifolium were planted in extensive and intensive green roof configurations using two different growing media. The first medium consisted of crushed brick, scoria, coir fibre and composted organics while the second comprised scoria, composted pine bark and hydro-cell flakes. Plant growth indices including vertical and horizontal growth rate, leaf succulence, shoot and root biomasses, water use efficiency and irrigation regimes were studied during a 12-month period. The results showed that the succulent species, C. rossii, can best tolerate the hot, dry summer conditions of South Australia, and this species showed a 100% survival rate and had the maximum horizontal growth rate, leaf succulence, shoot biomass and water use efficiency. All of the plants in the intensive green roofs with the crushed brick mix media survived during the term of this study. It was shown that stormwater can be used as a source of irrigation water for green roofs during 8 months of the year in Adelaide. However, supplementary irrigation is required for some of the plants over a full annual cycle. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. [Phenotypic plasticity and its regulation of tillers prolonged reproductive growth of Puccinellia tenuiflora population on alkalized meadow in Songnen Plains of China].

    Science.gov (United States)

    Sun, Ju; Yang, Yun-Fei

    2007-04-01

    Puccinellia tenuiflora is a salt-tolerant plant of grass family. By the method of random sampling, big samples of reproductive tillers of P. tenuiflora population on the alkalized meadow in the Songnen Plains of China were collected at early heading, heading, flowering, and milky stages, respectively, and the plasticity of their quantitative characters was analyzed. The results showed that except some fluctuations at flowering stage, the tiller height, tiller biomass, spike length and spike biomass of the reproductive tillers at other three growth stages increased significantly every five days with the increasing time of reproductive growth. At each growth stage, tiller height had a significant positive correlation with spike biomass, but a negative correlation with reproductive allocation. With the time of reproductive growth prolonged, the increasing rate of spike biomass at early heading, flowering and milky stages increased in power function with the increase of tiller height. The reproductive allocation decreased linearly by 43.2% and 44.31% at early heading and heading stages, respectively when the reproductive growth time increased ten days, and by 130% at milky stage when the time increased five days. The regulation of the tiller phenotypic plasticity of P. tenuiflora population at its reproductive growth stage followed definite patterns.

  4. The ageing phenome: caloric restriction and hormones promote neural cell survival, growth, and de-differentiation.

    Science.gov (United States)

    Timiras, Paola S; Yaghmaie, Farzin; Saeed, Omar; Thung, Elaine; Chinn, Garrett

    2005-01-01

    The phenome represents the observable properties of an organism that have developed under the continued influences of both genome and environmental factors. Phenotypic properties are expressed through the functions of cells, organs and body systems that operate optimally, close to equilibrium. In complex organisms, maintenance of the equilibrium is achieved by the interplay of several regulatory mechanisms. In the elderly, dynamic instability may lead to progressive loss of normal function, failure of adaptation and increased pathology. Extensive research (reported elsewhere in this journal) has demonstrated that genetic manipulations of endocrine signaling in flies, worms and mice increase longevity. Another effective strategy for prolonging the lifespan is caloric restriction: in data presented here, the persistence of estrogen-sensitive cells in the hypothalamus of caloric restricted 22-month-old female mice, may explain the persistence of reproductive function at an age, when reproductive function has long ceased in ad libitum fed controls. Still another strategy utilizes the effects of epidermal growth factor (EGF) to promote in vitro proliferation of neuroglia, astrocytes and oligodendrocytes. Their subsequent de-differentiation generates immature precursor cells potentially capable of differentiating into neuroblasts and neurons. These and other examples suggest that, in terms of functional outcomes, "the genome proposes but the phenome disposes".

  5. STI571 (Gleevec) improves tumor growth delay and survival in irradiated mouse models of glioblastoma

    International Nuclear Information System (INIS)

    Geng Ling; Shinohara, Eric T.; Kim, Dong; Tan Jiahuai; Osusky, Kate; Shyr, Yu; Hallahan, Dennis E.

    2006-01-01

    Purpose: Glioblastoma multiforme (GBM) is a devastating brain neoplasm that is essentially incurable. Although radiation therapy prolongs survival, GBMs progress within areas of irradiation. Recent studies in invertebrates have shown that STI571 (Gleevec; Novartis, East Hanover, NJ) enhances the cytotoxicity of ionizing radiation. In the present study, the effectiveness of STI571 in combination with radiation was studied in mouse models of GBM. Methods and Materials: Murine GL261 and human D54 GBM cell lines formed tumors in brains and hind limbs of C57BL6 and nude mice, respectively. GL261 and D54 cells were treated with 5 μmol/L of STI571 for 1 h and/or irradiated with 3 Gy. Protein was analyzed by Western immunoblots probed with antibodies to caspase 3, cleaved caspase 3, phospho-Akt, Akt, and platelet-derived growth factor receptor (PDGFR) α and β. Tumor volumes were assessed in mice bearing GL261 or D54 tumors treated with 21 Gy administered in seven fractionated doses. Histologic sections from STI571-treated mice were stained with phospho-Akt and phospho-PDGFR β antibodies. Kaplan-Meier survival curves were used to study the response of mice bearing intracranial implants of GL261. Results: STI571 penetrated the blood-brain barrier, which resulted in a reduction in phospho-PDGFR in GBM. STI571-induced apoptosis in GBM was significantly enhanced by irradiation. STI571 combined with irradiation induced caspase 3 cleavage in GBM cells. Glioblastoma multiforme response to therapy correlated with an increase in tumor growth delay and survival when STI571 was administered in conjunction with daily irradiation. Conclusion: These findings suggest that STI571 has the potential to augment radiotherapy and thereby improve median survival

  6. Glycosylation of inositol phosphorylceramide sphingolipids is required for normal growth and reproduction in Arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Tartaglio, Virginia [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Systems and Engineering Division; Rennie, Emilie A. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Systems and Engineering Division; Univ. of Nebraska, Lincoln, NE (United States). Center for Plant Science Innovation and Dept. of Biochemistry; Cahoon, Rebecca [Univ. of Nebraska, Lincoln, NE (United States). Center for Plant Science Innovation and Dept. of Biochemistry; Wang, George [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Systems and Engineering Division; Baidoo, Edward [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Systems and Engineering Division; Mortimer, Jennifer C. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Systems and Engineering Division; Cahoon, Edgar B. [Univ. of Nebraska, Lincoln, NE (United States). Center for Plant Science Innovation and Dept. of Biochemistry; Scheller, Henrik V. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Biological Systems and Engineering Division; Univ. of California, Berkeley, CA (United States). Dept. of Plant and Microbial Biology

    2016-09-19

    Sphingolipids are a major component of plant plasma membranes and endomembranes, and mediate a diverse range of biological processes. Study of the highly glycosylated glycosyl inositol phosphorylceramide (GIPC) sphingolipids has been slow as a result of challenges associated with the extractability of GIPCs, and their functions in the plant remain poorly characterized. We recently discovered an Arabidopsis GIPC glucuronosyltransferase, INOSITOL PHOSPHORYLCERAMIDE GLUCURONOSYLTRANSFERASE 1 (IPUT1), which is the first enzyme in the GIPC glycosylation pathway. Plants homozygous for the iput1 loss-of-function mutation were unobtainable, and so the developmental effects of reduced GIPC glucuronosylation could not be analyzed in planta. Using a pollen-specific rescue construct, we have here isolated homozygous iput1 mutants. The iput1 mutants show severe dwarfism, compromised pollen tube guidance, and constitutive activation of salicyclic acid-mediated defense pathways. The mutants also possess reduced GIPCs, increased ceramides, and an increased incorporation of short-chain fatty acids and dihydroxylated bases into inositol phosphorylceramides and GIPCs. The assignment of a direct role for GIPC glycan head groups in the impaired processes in iput1 mutants is complicated by the vast compensatory changes in the sphingolipidome; however, our results reveal that the glycosylation steps of GIPC biosynthesis are important regulated components of sphingolipid metabolism. In conclusion, this study corroborates previously suggested roles for GIPC glycans in plant growth and defense, suggests important role s for them in reproduction and demonstrates that the entire sphingolipidome is sensitive to their status.

  7. Reproductive performance of gilts according to growth rate and backfat thickness at mating.

    Science.gov (United States)

    Amaral Filha, W S; Bernardi, M L; Wentz, I; Bortolozzo, F P

    2010-08-01

    The study evaluated the influence of growth rate (GR) and backfat thickness (BF), at first mating of gilts, on the reproductive performance until the first farrowing and on the variation in birth weight of piglets. Gilts were categorized into three groups according to GR from birth until the first mating: GRI (600-700 g/d; n = 345), GRII (701-770 g/d; n = 710) and GRIII (771-870 g/d; n = 366). Analyses were also performed considering three groups formed according to BF (mm) at mating: BFI (10-15 mm; n = 405); BFII (16-17 mm; n = 649)and BFIII (18-23 mm; n = 367). There were no differences in farrowing rate and return to estrus rate among BF or GR groups (P > 0.05). GRII and GRIII females had larger litter size compared to GRI gilts (P GRI and GRII females. Moreover GRIII females had more piglets (P GRI females. More total born and born alive piglets were observed in BFII compared with BFI females (P 0.05). These results show that there is no advantage, in terms of farrowing rate and number of born alive, in performing the first mating of gilts with GR> 770 g/d and BF > 17 mm.

  8. Temperature modulates dengue virus epidemic growth rates through its effects on reproduction numbers and generation intervals.

    Science.gov (United States)

    Siraj, A. S.; Oidtman, R. J.; Huber, J. H.; Kraemer, M. U.; Brady, O. J.; Johansson, M. A.; Perkins, T. A.

    2017-12-01

    Epidemic growth rate, r, provides a more complete description of the potential for epidemics than the more commonly studied basic reproduction number, R0, yet the former has never been described as a function of temperature for dengue virus or other pathogens with temperature-sensitive transmission. The need to understand the drivers of epidemics of these pathogens is acute, with arthropod-borne virus epidemics becoming increasingly problematic. We addressed this need by developing temperature-dependent descriptions of the two components of r—R0 and the generation interval—to obtain a temperature-dependent description of r. Our results show that the generation interval is highly sensitive to temperature, decreasing twofold between 25 and 35 °C and suggesting that dengue virus epidemics may accelerate as temperatures increase, not only because of more infections per generation but also because of faster generations. Under the empirical temperature relationships that we considered, we found that r peaked at a temperature threshold that was robust to uncertainty in model parameters that do not depend on temperature. Although the precise value of this temperature threshold could be refined following future studies of empirical temperature relationships, the framework we present for identifying such temperature thresholds offers a new way to classify regions in which dengue virus epidemic intensity could either increase or decrease under future climate change.

  9. Effects of simulated Mars conditions on the survival and growth of Escherichia coli and Serratia liquefaciens.

    Science.gov (United States)

    Berry, Bonnie J; Jenkins, David G; Schuerger, Andrew C

    2010-04-01

    Escherichia coli and Serratia liquefaciens, two bacterial spacecraft contaminants known to replicate under low atmospheric pressures of 2.5 kPa, were tested for growth and survival under simulated Mars conditions. Environmental stresses of high salinity, low temperature, and low pressure were screened alone and in combination for effects on bacterial survival and replication, and then cells were tested in Mars analog soils under simulated Mars conditions. Survival and replication of E. coli and S. liquefaciens cells in liquid medium were evaluated for 7 days under low temperatures (5, 10, 20, or 30 degrees C) with increasing concentrations (0, 5, 10, or 20%) of three salts (MgCl(2), MgSO(4), NaCl) reported to be present on the surface of Mars. Moderate to high growth rates were observed for E. coli and S. liquefaciens at 30 or 20 degrees C and in solutions with 0 or 5% salts. In contrast, cell densities of both species generally did not increase above initial inoculum levels under the highest salt concentrations (10 and 20%) and the four temperatures tested, with the exception that moderately higher cell densities were observed for both species at 10% MgSO(4) maintained at 20 or 30 degrees C. Growth rates of E. coli and S. liquefaciens in low salt concentrations were robust under all pressures (2.5, 10, or 101.3 kPa), exhibiting a general increase of up to 2.5 orders of magnitude above the initial inoculum levels of the assays. Vegetative E. coli cells were maintained in a Mars analog soil for 7 days under simulated Mars conditions that included temperatures between 20 and -50 degrees C for a day/night diurnal period, UVC irradiation (200 to 280 nm) at 3.6 W m(-2) for daytime operations (8 h), pressures held at a constant 0.71 kPa, and a gas composition that included the top five gases found in the martian atmosphere. Cell densities of E. coli failed to increase under simulated Mars conditions, and survival was reduced 1 to 2 orders of magnitude by the interactive

  10. Opioid growth factor improves clinical benefit and survival in patients with advanced pancreatic cancer

    Directory of Open Access Journals (Sweden)

    Jill P Smith

    2010-03-01

    Full Text Available Jill P Smith1, Sandra I Bingaman1, David T Mauger2, Harold H Harvey1, Laurence M Demers3, Ian S Zagon41Departments of Medicine, 2Public Health Sciences, 3Pathology, and 4Neurosciences and Anatomy, Pennsylvania State University, College of Medicine, Hershey Medical Center, Hershey, PA, USABackground: Advanced pancreatic cancer carries the poorest prognosis of all gastrointestinal malignancies. Once the tumor has spread beyond the margins of the pancreas, chemotherapy is the major treatment modality offered to patients; however, chemotherapy does not significantly improve survival.Objective: Opioid growth factor (OGF; [Met5]-enkephalin is a natural peptide that has been shown to inhibit growth of pancreatic cancer in cell culture and in nude mice. The purpose of this study was to evaluate the effects of OGF biotherapy on subjects with advanced pancreatic cancer who failed chemotherapy.Methods: In a prospective phase II open-labeled clinical trial, 24 subjects who failed standard chemotherapy for advanced pancreatic cancer were treated weekly with OGF 250 μg/kg intravenously. Outcomes measured included clinical benefit, tumor response by radiographic imaging, quality of life, and survival.Results: Clinical benefit response was experienced by 53% of OGF-treated patients compared to historical controls of 23.8% and 4.8% for gemcitabine and 5-fluorouracil (5-FU, respectively. Of the subjects surviving more than eight weeks, 62% showed either a decrease or stabilization in tumor size by computed tomography. The median survival time for OGF-treated patients was three times that of untreated patients (65.5 versus 21 days, p < 0.001. No adverse effects on hematologic or chemistry parameters were noted, and quality of life surveys suggested improvement with OGF. Limitations: Measurements other than survival were not allowed in control patients, and clinical benefit comparisons were made to historical controls.Conclusion: OGF biotherapy improves the

  11. Growth and survival of Apache Trout under static and fluctuating temperature regimes

    Science.gov (United States)

    Recsetar, Matthew S.; Bonar, Scott A.; Feuerbacher, Olin

    2014-01-01

    Increasing stream temperatures have important implications for arid-region fishes. Little is known about effects of high water temperatures that fluctuate over extended periods on Apache Trout Oncorhynchus gilae apache, a federally threatened species of southwestern USA streams. We compared survival and growth of juvenile Apache Trout held for 30 d in static temperatures (16, 19, 22, 25, and 28°C) and fluctuating diel temperatures (±3°C from 16, 19, 22 and 25°C midpoints and ±6°C from 19°C and 22°C midpoints). Lethal temperature for 50% (LT50) of the Apache Trout under static temperatures (mean [SD] = 22.8 [0.6]°C) was similar to that of ±3°C diel temperature fluctuations (23.1 [0.1]°C). Mean LT50 for the midpoint of the ±6°C fluctuations could not be calculated because survival in the two treatments (19 ± 6°C and 22 ± 6°C) was not below 50%; however, it probably was also between 22°C and 25°C because the upper limb of a ±6°C fluctuation on a 25°C midpoint is above critical thermal maximum for Apache Trout (28.5–30.4°C). Growth decreased as temperatures approached the LT50. Apache Trout can survive short-term exposure to water temperatures with daily maxima that remain below 25°C and midpoint diel temperatures below 22°C. However, median summer stream temperatures must remain below 19°C for best growth and even lower if daily fluctuations are high (≥12°C).

  12. Survival and Growth of Probiotic Lactic Acid Bacteria in Refrigerated Pickle Products.

    Science.gov (United States)

    Fan, Sicun; Breidt, Fred; Price, Robert; Pérez-Díaz, Ilenys

    2017-01-01

    We examined 10 lactic acid bacteria that have been previously characterized for commercial use as probiotic cultures, mostly for dairy products, including 1 Pediococcus and 9 Lactobacilli. Our objectives were to develop a rapid procedure for determining the long-term survivability of these cultures in acidified vegetable products and to identify suitable cultures for probiotic brined vegetable products. We therefore developed assays to measure acid resistance of these cultures to lactic and acetic acids, which are present in pickled vegetable products. We used relatively high acid concentrations (compared to commercial products) of 360 mM lactic acid and 420 mM acetic acid to determine acid resistance with a 1 h treatment. Growth rates were measured in a cucumber juice medium at pH 5.3, 4.2, and 3.8, at 30 °C and 0% to 2% NaCl. Significant differences in acid resistance and growth rates were found among the 10 cultures. In general, the acid resistant strains had slower growth rates than the acid sensitive strains. Based on the acid resistance data, selected cultures were tested for long-term survival in a simulated acidified refrigerated cucumber product. We found that one of the most acid resistant strains (Lactobacillus casei) could survive for up to 63 d at 4 °C without significant loss of viability at 10 8 CFU/mL. These data may aid in the development of commercial probiotic refrigerated pickle products. © 2016 Institute of Food Technologists®.

  13. Growth and survival of sea lampreys from metamorphosis to spawning in Lake Huron

    Science.gov (United States)

    Swink, William D.; Johnson, Nicholas S.

    2014-01-01

    Larval Sea Lampreys Petromyzon marinus live burrowed in stream bottoms and then metamorphose into their parasitic stage. Among larvae that metamorphose in a given year (i.e., parasitic cohort), autumn out-migrants (October–December) to the Laurentian Great Lakes can feed on fish for up to 6 months longer than spring outmigrants (March–May), which overwinter in streams without feeding. We evaluated whether the season of outmigration affected growth or survival of newlymetamorphosed Sea Lampreys in LakeHuron. Newlymetamorphosed individuals (n=2,718) from three parasitic cohorts were netted during their out-migration from BlackMallard Creek, Michigan, to LakeHuron during autumn 1997 through spring 2000; each out-migrant was injected with a sequentially numbered coded wire tag and was released back into the creek. After up to 18 months of feeding in the Great Lakes, 224 (8.2%) Sea Lampreys were recaptured (in 1999–2001) as upstream-migrating adults in tributaries to Lakes Huron and Michigan. Recovery rates of autumn and spring out-migrants as adults were 9.4% and 7.8%, respectively, and these rates did not significantly differ. Overwinter feeding (i.e., as parasites) by autumn out-migrants did not produce adult mean sizes greater than those of spring out-migrants. Because we detected no growth or survival differences between autumn and spring out-migrants, the capture of newly metamorphosed Sea Lampreys at any point during their out-migration should provide equal reductions in damage to Great Lakes fisheries. The absence of a difference in growth or survival between autumn and spring out-migrants is an aspect of Sea Lamprey life history that yields resiliency to this invasive parasite and complicates efforts for its control in the Great Lakes.

  14. Exogenous applications of plant growth regulators influence the reproductive growth of citrus sinensis osbeck cv. blood red

    International Nuclear Information System (INIS)

    Khan, A.S.; Malik, A.U.; Ahmad, S.; Ahmad, I.

    2014-01-01

    To study the influence of exogenous applications of plant growth regulators on the reproductive behaviour of low bearing sweet orange (Citrus sinensis Osbeck) trees, three separate experiments were conducted on twelve years old 'Blood Red' Sweet orange trees budded on Rough Lemon (Citrus jambheri L.) root stock. In the first experiment, trees were sprayed with 20 mg L-1 2, 4-D and GA3 alone or in combination at mid bloom (MB) stage, whilst in the second and third experiments 20 mg L-1 2, 4-D and GA3 alone or in combination were sprayed at MB + 6 weeks after MB, and at MB + 22 and 28 weeks after MB stages, respectively. A single tree was selected as an experimental unit and each treatment was replicated four times. Data regarding the flowering intensity, flower drop, fruit set, fruit drop and fruit harvest percentages (%) were collected and analyzed statistically. In all experiments exogenous application of 20 mg L-1 2, 4-D and GA3 alone or in combination to Blood Red sweet orange trees reduced the flower drop % and increased the fruit set % as compared to untreated trees. Application 2, 4-D and GA3 alone or in combination at MB did not affect the fruit drop % and fruit harvest % in contrast to untreated trees. The trees sprayed with 20 mg L-1 GA3 alone or in combination with 2, 4-D at MB + 22 and 28 weeks after MB exhibited highest reduction in the fruit drop % compared to control trees. In conclusions application GA3 (20 mg L-1) alone or in combination of 2, 4-D (20 mg L-1) at MB + 22 and 28 weeks after MB can be used effectively to increase the fruit set and reduce the fruit drop in Blood Red sweet oranges. (author)

  15. Artificially regenerating longleaf pine on wet sites: preliminary analysis of effects of site preparation treatments on early survival and growth

    Science.gov (United States)

    Benjamin O. Knapp; G. Geoff Wang; Joan L. Walker

    2010-01-01

    Our study, conducted over two years on poorly drained, sandy sites in Onslow County, NC, compared the effects of eight common site preparation treatments on early survival and growth of planted longleaf pine seedlings. Through two growing seasons, we found survival to be similar across all treatments (p = 0.8806), but root collar diameter was greatest with combinations...

  16. Extracapsular growth of lymph node metastases in squamous cell carcinoma of the vulva. The impact on recurrence and survival

    NARCIS (Netherlands)

    van der Velden, J.; van Lindert, A. C.; Lammes, F. B.; ten Kate, F. J.; Sie-Go, D. M.; Oosting, H.; Heintz, A. P.

    1995-01-01

    Patients with squamous cell carcinoma of the vulva who present with multiple positive groin lymph nodes have poor survival. Growth of cancer through the capsule of the groin lymph nodes recently has been identified as an important prognostic factor for survival in that patient group. The objective

  17. Effect of single-dose radiation on cell survival and growth hormone secretion by rat anterior pituitary cells

    International Nuclear Information System (INIS)

    Hochberg, Z.; Kuten, A.; Hertz, P.; Tatcher, M.; Kedar, A.; Benderly, A.

    1983-01-01

    Cranial irradiation has been shown to impair growth hormone secretion in children. In this study a cell culture of dispersed rat anterior pituitary cells was exposed to single doses of radiation in the range of 100 to 1500 rad. Survival curves were obtained for the different anterior pituitary cell lines, and growth hormone secretion was measured in the tissue culture medium. Both survival and growth hormone secretion curves showed an initial shoulder in the range of 0 to 300 rad, followed by a decline between 300 to 750 rad. It is concluded that growth hormone secreting acidophilic pituicytes are sensitive to radiation at single doses greater than 300 rad

  18. Effects of basal area on survival and growth of longleaf pine when practicing selection silviculture

    International Nuclear Information System (INIS)

    Kara, F.; Loewenstein, E.F.; Brockway, D.G.

    2017-01-01

    Aim of study: Uneven-aged (UEA) management systems can achieve multiple-use objectives, however, use of UEA techniques to manage longleaf pine (Pinus palustris Mill.) forests are still open to question, because of the species’ intolerance of competition. It was our aim to examine the influence of different levels (9.2, 13.8 and 18.4 m2 ha-1) of residual basal area (RBA) on longleaf pine seedling survival and growth following three growing seasons. Area of study: This study was conducted at the Escambia Experimental Forest, located on the Southern Coastal Plain of Alabama, in the southeastern United States. Material and Methods: Selection silviculture was implemented with the Proportional-Basal Area (Pro-B) method. Prescribed burning was conducted before seed dispersal and in the second year after germination. Photosynthetically active radiation (PAR) was measured under the canopy in the study plots. Survival and growth of longleaf pine seedlings were observed for three growing seasons. Main results: An inverse relationship was found between the number of germinants and RBA, but the mortality of germinants and planted seedlings was not affected by RBA. At age three, an inverse relationship was observed between root-collar diameter (RCD) growth of the germinants and RBA, but RCD growth of planted seedlings was not affected by RBA. Most of the study plots contained more than the projected number of seedlings needed to sustain the target diameter structure. Research highlights: Long-term continuous monitoring of seedling development and recruitment into canopy is required to determine the efficacy of UEA management. However, current data suggest that UEA methods may be a viable alternative to the use of even-aged (EA) methods in longleaf ecosystems.

  19. Effects of basal area on survival and growth of longleaf pine when practicing selection silviculture

    Energy Technology Data Exchange (ETDEWEB)

    Kara, F.; Loewenstein, E.F.; Brockway, D.G.

    2017-11-01

    Aim of study: Uneven-aged (UEA) management systems can achieve multiple-use objectives, however, use of UEA techniques to manage longleaf pine (Pinus palustris Mill.) forests are still open to question, because of the species’ intolerance of competition. It was our aim to examine the influence of different levels (9.2, 13.8 and 18.4 m2 ha-1) of residual basal area (RBA) on longleaf pine seedling survival and growth following three growing seasons. Area of study: This study was conducted at the Escambia Experimental Forest, located on the Southern Coastal Plain of Alabama, in the southeastern United States. Material and Methods: Selection silviculture was implemented with the Proportional-Basal Area (Pro-B) method. Prescribed burning was conducted before seed dispersal and in the second year after germination. Photosynthetically active radiation (PAR) was measured under the canopy in the study plots. Survival and growth of longleaf pine seedlings were observed for three growing seasons. Main results: An inverse relationship was found between the number of germinants and RBA, but the mortality of germinants and planted seedlings was not affected by RBA. At age three, an inverse relationship was observed between root-collar diameter (RCD) growth of the germinants and RBA, but RCD growth of planted seedlings was not affected by RBA. Most of the study plots contained more than the projected number of seedlings needed to sustain the target diameter structure. Research highlights: Long-term continuous monitoring of seedling development and recruitment into canopy is required to determine the efficacy of UEA management. However, current data suggest that UEA methods may be a viable alternative to the use of even-aged (EA) methods in longleaf ecosystems.

  20. Aster leafhopper survival and reproduction, and Aster yellows transmission under static and fluctuating temperatures, using ddPCR for phytoplasma quantification

    OpenAIRE

    Bahar, Md H.; Wist, Tyler J.; Bekkaoui, Diana R.; Hegedus, Dwayne D.; Olivier, Chrystel Y.

    2018-01-01

    Aster yellows (AY) is an important disease of Brassica crops and is caused by Candidatus Phytoplasma asteris and transmitted by the insect vector, Aster leafhopper (Macrosteles quadrilineatus). Phytoplasma-infected Aster leafhoppers were incubated at various constant and fluctuating temperatures ranging from 0 to 35 °C with the reproductive host plant barley (Hordium vulgare). At 0 °C, leafhopper adults survived for 18 days, but failed to reproduce, whereas at 35 °C insects died within 18 day...

  1. Effects of vitamin C on percent neurulation, hatch, growth, and survival of hybrid catfish challenged with virulent Edwardsiella ictaluri

    Science.gov (United States)

    Vitamin C (ascorbic acid) is an essential micronutrient involved in several physiological processes such as growth, reproduction, and immune response. Requirements of vitamin C during gamete formation and early life stages of catfish are not known. Ascorbic acid (1 mg/mL/kg BW) was administered in...

  2. Growth and reproduction of the sea snake, Emydocephalus ijimae, in the central Ryukyus, Japan: a mark and recapture study.

    Science.gov (United States)

    Masunaga, Gen; Ota, Hidetoshi

    2003-04-01

    A mark and recapture study was carried out for three years on a population of the Ijima's sea snake, Emydocephalus ijimae, in the coastal shallow water of Zamamijima Island, central Ryukyus, Japan. The relatively high recapture (47% of 167 marked snakes) suggests that E. ijimae is a particularly philopatric, sedentary species among the sea snakes. The sex ratio (male: female), approximately 1.6:1, significantly skewed from 1:1. The growth rate in SVL declined with growth, with females thoroughly growing better than males. Males and females were estimated to begin reproductive activity in the second or third summer and the third spring after birth, respectively. Frequency of female reproduction is guessed to vary from annual to biennial, or even less frequent.

  3. Initial effects of quinclorac on the survival and growth of high biomass tree species

    Directory of Open Access Journals (Sweden)

    Joshua P. Adams

    2017-07-01

    Full Text Available Increasingly, short rotation woody crops are being planted for biofuel/biomass production on unused lands or marginal agricultural lands. Many of these plantations occur near agriculture land which is intensively managed including yearly herbicide applications. Herbicide drift from these applications may cause tree stress and decreasing yields impacting potential biomass production. Quinclorac, a rice herbicide, is often cited as a potential source of tree damage and is the focal herbicide of this study. Five planting stocks, including three eastern cottonwood clones, a hybrid poplar clone, and American sycamore, were assessed for herbicide affects and deployed at three sites across south Arkansas. Stocks were exposed to a full rate labeled for rice (3.175 L ha-1, two rates simulating drift (1/100th and 1/10th the full rate, and a no-spray control. Survival of all Populus clones decreased drastically as quinclorac rate increased, while there was little observed effect on American sycamore. Some variability in treatment response among poplars occurred below the full herbicide rate; however, direct spraying a full herbicide rate on poplars resulted in survival rates below 65 percent and negative growth rates due to dieback. Conversely, photosynthetic rates of remaining leaves increased as quinclorac rate increased. Survival and damage scores of American sycamore, regardless of herbicide rate, remained nearly constant.

  4. Effects of feed species and HUFA composition on survival and growth of the longsnout seahorse (Hippocampus reidi

    Directory of Open Access Journals (Sweden)

    Patrick eSchubert

    2016-04-01

    Full Text Available Globally, wild seahorse populations are threatened due to, habitat destruction and unsustainable human exploitation among others. Furthermore, aquaculture-based mass-scale rearing is still uncommon due to the low survival rates of seahorse juveniles and exceptionally high feed costs. Previous studies have demonstrated the importance of both highly unsaturated fatty acid (HUFA supplies and a copepod-based rearing for seahorse survival and growth. As the latter is expensive, the question arises as to how high survival rates of seahorse juveniles can be assured under low- to moderate-cost feed regimes. In particular, it remains unknown whether the diet species or their dietary HUFA profiles determine the successful development of seahorse fry.Therefore, the aims of this study were to assess the dependence of growth and survival rates of Hippocampus reidi brood on the animal feed and to infer the impact of feed species vs. dietary HUFA profiles on juvenile growth. A nutrition experiment was conducted where juveniles were treated either with enriched Artemia nauplii (low-cost diet Art or with a mixed diet of Artemia and copepods (moderate-cost diet Art/Cop. Larval survival and growth were analyzed using Cox proportional-hazard and mixed linear model analyses. We found that i both diets enabled good survival, ii diet Art/Cop resulted in superior weight and height growth, and iii the differential effects of diets Art/Cop and Art cannot be explained by their different HUFA compositions alone.From an economical point of view, our findings of high survival rates and relatively high growth rates with the medium-cost treatment Art/Cop may open new possibilities for the large-scale rearing of seahorses. Even the application of a low-cost Art diet might be appropriate for seahorse aquacultures as both survival and growth rates are only marginally lower compared to the former diet.

  5. Effect of restricted feeding under rearing on reproduction, body condition and blood metabolites of rabbit does selected for growth rate

    Directory of Open Access Journals (Sweden)

    C. Naturil-Alfonso

    2017-12-01

    Full Text Available Young rabbit females selected for growth rate can have nutritional needs which may not be met by the common practice of feed restriction during rearing in commercial rabbit production. The aim of this study was to analyse the effect of two different feeding programmes: restricted and ad libitum feeding, applied in young rabbit females for one month at the end of rearing, on reproductive performance, body condition and circulating metabolic hormones and metabolites in a rabbit line selected by growth rate in 3 consecutive reproductive cycles. Thus, twenty-four 16-week-old does were randomly assigned to a group in which the daily recommended nutrient intakes were satisfied (fed restricted: 130 g/day, n=13 or a group fed to satiety (ad libitum: 235.5 g/day, n=11 during one month. Then, all does were inseminated in 3 consecutive cycles using a 42-day reproductive cycle. Measurements of does’ body weight, perirenal fat thickness and plasma leptin, non-esterified-fatty-acids (NEFA, beta-hydroxybutyrate (BOHB and fructosamine were performed at artificial insemination (AI, parturition and weaning time in 3 consecutive cycles. Reproductive performance of does was evaluated based on fertility, litter size at parturition, prolificacy and productivity. Differences in body weight were found only in the 1st cycle, ad libitum fed females being heavier than restricted ones. Nevertheless, body weight variances disappeared in later cycles. No differences were found in perirenal fat thickness. Finally, in ad libitum fed females slight differences were found in plasma levels of NEFAs (452 vs. 258 μekv/L and 527 vs. 306 μekv/L for 1st and 2nd cycles and BOHB (0.26 vs. 0.03 mM for 2nd cycle, but disappeared in the 3rd reproductive cycle. Fertility, prolificacy and productivity was not significantly affected by the feeding programme. Nevertheless, total litter size showed to be higher in ad libitum fed females at second parturition (8.7 vs. 5.9 kits. Therefore

  6. Resource availability and competition shape the evolution of survival and growth ability in a bacterial community.

    Directory of Open Access Journals (Sweden)

    Minna Pekkonen

    Full Text Available Resource availability is one of the main factors determining the ecological dynamics of populations or species. Fluctuations in resource availability can increase or decrease the intensity of resource competition. Resource availability and competition can also cause evolutionary changes in life-history traits. We studied how community structure and resource fluctuations affect the evolution of fitness related traits using a two-species bacterial model system. Replicated populations of Serratia marcescens (copiotroph and Novosphingobium capsulatum (oligotroph were reared alone or together in environments with intergenerational, pulsed resource renewal. The comparison of ancestral and evolved bacterial clones with 1 or 13 weeks history in pulsed resource environment revealed species-specific changes in life-history traits. Co-evolution with S. marcescens caused N. capsulatum clones to grow faster. The evolved S. marcescens clones had higher survival and slower growth rate then their ancestor. The survival increased in all treatments after one week, and thereafter continued to increase only in the S. marcescens monocultures that experienced large resource pulses. Though adaptive radiation is often reported in evolution studies with bacteria, clonal variation increased only in N. capsulatum growth rate. Our results suggest that S. marcescens adapted to the resource renewal cycle whereas N. capsulatum was more affected by the interspecific competition. Our results exemplify species-specific evolutionary response to both competition and environmental variation.

  7. Predicting the Performance and Survival of Islamic Banks in Malaysia to Achieve Growth Sustainability

    Directory of Open Access Journals (Sweden)

    Mazuin Sapuan Noraina

    2017-01-01

    Full Text Available In Malaysia, the growth of the Islamic financial industry has increased tremendously in line with the Government’s ambition to make Malaysia as an international hub for Islamic finance since 2010. With the increasing number of foreign players in this industry plus with the increasing demand from domestic and foreign customers would further enhance the possibility for Malaysia to achieve this ambition. Currently, according to the Economic Transformation Programme, 2012 Malaysia is the world’s third largest market for Shariah assets that cover Islamic banks, Takaful, and sukuk. Malaysia as one of the main contributors to the global Islamic financial assets with Islamic assets in Malaysia grew by 23.8% in 2011 from RM350.8bil to RM434.6bil. The issues of predicting the performance and the survival of Islamic Banks in Malaysia become amongst crucial issues in academic research. By employing multi – layer perceptron neural network and pooled regression, we found that total assets/ size of the Islamic banks (GROWTH have high weightage and significantly influence in predicting the performance and the survival of Islamic banks in Malaysia. With the increasing number of Islamic banking institutions in Malaysia, this study can give insight on the sustainability of the Islamic banking system in Malaysia for the benefit of the investors, shareholder and depositors.

  8. Effects of sublethal exposure to boric acid sugar bait on adult survival, host-seeking, bloodfeeding behavior, and reproduction of Stegomyia albopicta.

    Science.gov (United States)

    Ali, Arshad; Xue, Rui-De; Barnard, Donald R

    2006-09-01

    Effects of sublethal exposure to 0.1% boric acid sugar bait on adult survival, host-seeking, bloodfeeding behavior, and reproduction of Stegomyia albopicta were studied in the laboratory. Survival of males as well as females was significantly reduced when exposed to the bait, compared to control adults. The host-seeking and bloodfeeding activities in the baited females decreased, but the mean duration of blood engorgement (probing to voluntary withdrawal of proboscis) was not significantly different between the baited and control females. The landing and biting rates (human forearm) were significantly reduced in the baited females compared to nonbaited controls. Fecundity and fertility (based on number of laid eggs per female and percentage egg hatch, respectively) in the baited females were significantly reduced, and ovarian development was retarded. Sublethal exposure to sugar-based boric acid bait has the potential to reduce adult populations of St. albopicta.

  9. Survival, growth and stress response of juvenile tidewater goby, Eucyclogobius newberryi, to interspecific competition for food

    Science.gov (United States)

    Chase, Daniel A; Flynn, Erin E; Todgham, Anne E

    2016-01-01

    Abstract Reintroduction of endangered fishes to historic habitat has been used as a recovery tool; however, these fish may face competition from other fishes that established in their native habitat since extirpation. This study investigated the physiological response of tidewater goby, Eucyclogobius newberryi, an endangered California fish, when competing for food with threespine stickleback, Gasterosteus aculeatus, a native species, and rainwater killifish, Lucania parva, a non-native species. Survival, growth and physiological indicators of stress (i.e. cortisol, glucose and lactate concentrations) were assessed for juvenile fish held for 28 days in two food-limited conditions. When fed a 75% ration, survival of E. newberryi was significantly lower when held with G. aculeatus. In all fish assemblages, weight and relative condition decreased then stabilized over the 28 day experiment, while length remained unchanged. Whole-body cortisol in E. newberryi was not affected by fish assemblage; however, glucose and lactate concentrations were significantly higher with conspecifics than with other fish assemblages. When fed a 50% ration, survival of E. newberryi decreased during the second half of the experiment, while weight and relative condition decreased and length remained unchanged in all three fish assemblages. Cortisol concentrations were significantly higher for all fish assemblages compared with concentrations at the start of the experiment, whereas glucose and lactate concentrations were depressed relative to concentrations at the start of the experiment, with the magnitude of decrease dependent on the species assemblage. Our findings indicate that E. newberryi exhibited reduced growth and an elevated generalized stress response during low food availability. In response to reduced food availability, competition with G. aculeatus had the greatest physiological effect on E. newberryi, with minimal effects from the non-native L. parva. This study presents

  10. The relationship between early growth and survival of hatchling saltwater crocodiles (Crocodylus porosus in captivity.

    Directory of Open Access Journals (Sweden)

    Matthew L Brien

    Full Text Available Hatchling fitness in crocodilians is affected by "runtism" or failure to thrive syndrome (FTT in captivity. In this study, 300 hatchling C. porosus, artificially incubated at 32°C for most of their embryonic development, were raised in semi-controlled conditions, with growth criteria derived for the early detection of FTT (within 24 days. Body mass, four days after hatching (BM4d, was correlated with egg size and was highly clutch specific, while snout-vent length (SVL4d was much more variable within and between clutches. For the majority of hatchlings growth trajectories within the first 24 days continued to 90 days and could be used to predict FTT affliction up to 300 days, highlighting the importance of early growth. Growth and survival of hatchling C. porosus in captivity was not influenced by initial size (BM4d, with a slight tendency for smaller hatchlings to grow faster in the immediate post-hatching period. Strong clutch effects (12 clutches on affliction with FTT were apparent, but could not be explained by measured clutch variables or other factors. Among individuals not afflicted by FTT (N = 245, mean growth was highly clutch specific, and the variation could be explained by an interaction between clutch and season. FTT affliction was 2.5 times higher among clutches (N = 7 that hatched later in the year when mean minimum air temperatures were lower, compared with those clutches (N = 5 that hatched early in the year. The results of this study highlight the importance of early growth in hatchling C. porosus, which has implications for the captive management of this species.

  11. Growth, mortality and reproduction of the blue tilapia Oreochromis aureus (Perciformes: Cichlidae) in the Aguamilpa Reservoir, Mexico.

    Science.gov (United States)

    Peña Messina, Emilio; Tapia Varela, Raul; Velázquez Abunader, José Iván; Orbe Mendoza, Alma Araceli; Velazco Arce, Javier Marcial de Jesús Ruiz

    2010-12-01

    Tilapia production has increased in Aguamilpa Reservoir, in Nayarit, Mexico, in the last few years and represents a good economic activity for rural communities and the country. We determined growth parameters, mortality and reproductive aspects for 2413 specimens of blue tilapia Oreochromis aureus in this reservoir. Samples were taken monthly from July 2000 through June 2001, of which 1 371 were males and 1 042 were females. Standard length (SL) and total weight (TW) were measured in each organism. The SL/TW relationships through power models for sexes were determined. The growth parameters L infinity k, and t0 of the von Bertalanffy equation were estimated using frequency distribution of length through ELEFAN-I computer program. Finally the reproductive cycle and size of first maturity were established using morph chromatic maturity scale. The results suggested that the males and females had negative allometric growth (b overfishing. Blue tilapia reproduces year-round; the highest activity occurs from January through May and size of first maturity was 23 cm SL. We conclude that it is necessary to establish a minimum catch size in this reservoir based on the reproductive behavior of this species.

  12. Effect of temperature on growth, mortality, reproduction, and production of adult Lymnaea obrussa Say (Mollusca:Gastropoda)

    International Nuclear Information System (INIS)

    Mattice, J.S.

    1975-01-01

    Shell lengths and egg production were measured weekly under constant (K; 10, 15, 20, 25 0 C) and varying temperature regimes during the reproductive period. Varying regimes included natural field temperature in a pond (F; diurnal and seasonal), mean daily field temperature (anti F; seasonal) and 5 and 10 0 C above anti F. Growth rate of large snails (>10 mm) was unaffected by temperature, but small snails (6 to 10 mm) grew fastest at 15 0 C(K). Growth and reproductive periods were longest, production was highest, and mortality rate was lowest at 15 0 C(K). Rate (per snail) of egg production increased with temperature. At equal mean temperature, regime affected growth rate only at anti F. Regime affected the following values as shown: mortality rate,F > anti F = K; rate of reproduction, F > K > anti F; and total production, K > anti F = F. The validity of extrapolation of energetic data from laboratory to field is discussed. Data relating production and temperature are valuable in thermal impact analysis. (U.S.)

  13. Enhancement of trophoblast differentiation and survival by low molecular weight heparin requires heparin-binding EGF-like growth factor.

    Science.gov (United States)

    Bolnick, Alan D; Bolnick, Jay M; Kohan-Ghadr, Hamid-Reza; Kilburn, Brian A; Pasalodos, Omar J; Singhal, Pankaj K; Dai, Jing; Diamond, Michael P; Armant, D Randall; Drewlo, Sascha

    2017-06-01

    Does low molecular weight heparin (LMWH) require heparin-binding epidermal growth factor (EGF)-like growth factor (HBEGF) signaling to induce extravillous trophoblast differentiation and decrease apoptosis during oxidative stress? LMWH increased HBEGF expression and secretion, and HBEGF signaling was required to stimulate trophoblast extravillous differentiation, increase invasion in vitro and reduce trophoblast apoptosis during oxidative stress. Abnormal trophoblast differentiation and survival contribute to placental insufficiency syndromes, including preeclampsia and intrauterine growth restriction. Preeclampsia often manifests as a pro-thrombotic state, with unsuccessful transformation of the spiral arteries that reduces oxygen supply and can produce placental infarction. LMWH improves placental function by increasing blood flow. Recent data suggest that the actions of LMWH transcend its anti-coagulative properties, but the molecular mechanism is unknown. There is evidence that LMWH alters the expression of human HBEGF in trophoblast cells, which regulates human trophoblast pathophysiology. HBEGF, itself, is capable of increasing trophoblast survival and invasiveness. First-trimester placental explants and the HTR-8/SVneo cell line, established using extravillous trophoblast outgrowths from first-trimester villous explants, were treated in vitro with LMWH to examine the effects on HBEGF signaling and trophoblast function under normal physiological and pathological conditions. A highly specific antagonist of HBEGF and other inhibitors of HBEGF downstream signaling were used to determine the relationship between LMWH treatment and HBEGF. Placental tissues (n = 5) were obtained with IRB approval and patient consent from first-trimester terminations. Placental explants and HTR-8/SVneo cells were cultured on plastic or Matrigel™ and treated with a therapeutic dose of LMWH (Enoxaparin; 10 IU/ml), with or without CRM197, pan Erb-B2 Receptor Tyrosine Kinase (ERBB

  14. The effects of 137Cs irradiation and MAP on the survival and growth of salmonella Spp in pork

    International Nuclear Information System (INIS)

    Gao Meixu

    2000-01-01

    The effects of 137 Cs irradiation (0 to 2 kGy) and MAP combination treatment on the survival and growth of Salmonella Spp are studied in sterile pork in the absence of competing microflora. A central composite response-surface design is used to test the response of the pathogen to the treatments in a single experiment. Predictive equations are developed from the analyses of variances of the resulting data. The results show that the survival of Salmonella is significant decrease with the increasing of irradiation dose, but there are no evident effects on the survival of salmonella due to the MAP. Five kinds of MAP do not show the difference on the growth of Salmonella. 50% CO 2 treatment shows the irradiation protection of Salmonella compared with air. The results indicate that the treatment combined irradiation with MAP is not more effective for controlling the survival and growth of Salmonella Spp

  15. Fungal Morphogenesis, from the Polarized Growth of Hyphae to Complex Reproduction and Infection Structures.

    Science.gov (United States)

    Riquelme, Meritxell; Aguirre, Jesús; Bartnicki-García, Salomon; Braus, Gerhard H; Feldbrügge, Michael; Fleig, Ursula; Hansberg, Wilhelm; Herrera-Estrella, Alfredo; Kämper, Jörg; Kück, Ulrich; Mouriño-Pérez, Rosa R; Takeshita, Norio; Fischer, Reinhard

    2018-06-01

    Filamentous fungi constitute a large group of eukaryotic microorganisms that grow by forming simple tube-like hyphae that are capable of differentiating into more-complex morphological structures and distinct cell types. Hyphae form filamentous networks by extending at their tips while branching in subapical regions. Rapid tip elongation requires massive membrane insertion and extension of the rigid chitin-containing cell wall. This process is sustained by a continuous flow of secretory vesicles that depends on the coordinated action of the microtubule and actin cytoskeletons and the corresponding motors and associated proteins. Vesicles transport cell wall-synthesizing enzymes and accumulate in a special structure, the Spitzenkörper, before traveling further and fusing with the tip membrane. The place of vesicle fusion and growth direction are enabled and defined by the position of the Spitzenkörper, the so-called cell end markers, and other proteins involved in the exocytic process. Also important for tip extension is membrane recycling by endocytosis via early endosomes, which function as multipurpose transport vehicles for mRNA, septins, ribosomes, and peroxisomes. Cell integrity, hyphal branching, and morphogenesis are all processes that are largely dependent on vesicle and cytoskeleton dynamics. When hyphae differentiate structures for asexual or sexual reproduction or to mediate interspecies interactions, the hyphal basic cellular machinery may be reprogrammed through the synthesis of new proteins and/or the modification of protein activity. Although some transcriptional networks involved in such reprogramming of hyphae are well studied in several model filamentous fungi, clear connections between these networks and known determinants of hyphal morphogenesis are yet to be established. Copyright © 2018 American Society for Microbiology.

  16. Xylem-to-phloem transfer of boron in broccoli and lupin during early reproductive growth

    Energy Technology Data Exchange (ETDEWEB)

    Shelp, B J; Kitheka, A M; Cauwenberghe, O.R. Van [Univ. of Guelph, Dept. of Horticultural Science, Guelph, ON (Canada); Vanderpool, R A [Grand Forks Human Nutrition Research Center, Agricultural Research service, Grand Forks, ND (United States); Spiers, G A [Univ. of Guelph, Dept. of Land Resource Science, Guelph, ON (Canada)

    1998-12-01

    The aim of this study was to test the hypothesis that newly-acquired boron (B) undergoes rapid xylem-to-phloem transfer in plants with restricted mobility. Analysis of the element accumulation and water usage by shoots of intact broccoli (Brassica oleracea var. italica Plenck cv. Commander) and lupin (Lupinus albus L. cv. Ultra) plants provided with a non-deficient supply of B, revealed that the concentration of various mineral elements (K, P, Mg, Ca, B, Fe, Zn, Mo, Cu, Mn) in xylem sap of intact plants ranged from 0.3 {mu}M to 3.5 mM, with B being present at 2.9-3.5 {mu}M. For each element assayed, the concentration was higher in phloem exudate (1.6 {mu}M to 91 mM) than in xylem sap; B was present at about 0.4 mM. Intact broccoli and lupin plants or detached transpiring broccoli shoots were supplied simultaneously with enriched {sup 10}B, strontium (a xylem marker) and rubidium (a xylem/phloem marker) during early reproductive growth. The contents of these three compounds were determined in foliage and florets or fruits as a function of time (i.e. up to 12 h and 4 days for broccoli and lupin plants, respectively), and the content in florets or fruits was expressed as a percent of the total recovered. In general, the percent recovery of both {sup 10}B and rubidium in florets or fruits was similar and markedly greater than that for strontium, even at the earliest harvest times (within 2 h for broccoli and 1 day for lupin). The data indicate that in plants with restricted B mobility, B is supplied to sink tissues in the phloem, and the extent of B xylem-to-phloem transfer is closely determined by current uptake. (au) 35 refs.

  17. Xylem-to-phloem transfer of boron in broccoli and lupin during early reproductive growth

    International Nuclear Information System (INIS)

    Shelp, B.J.; Kitheka, A.M.; Cauwenberghe, O.R. Van; Vanderpool, R.A.; Spiers, G.A.

    1998-01-01

    The aim of this study was to test the hypothesis that newly-acquired boron (B) undergoes rapid xylem-to-phloem transfer in plants with restricted mobility. Analysis of the element accumulation and water usage by shoots of intact broccoli (Brassica oleracea var. italica Plenck cv. Commander) and lupin (Lupinus albus L. cv. Ultra) plants provided with a non-deficient supply of B, revealed that the concentration of various mineral elements (K, P, Mg, Ca, B, Fe, Zn, Mo, Cu, Mn) in xylem sap of intact plants ranged from 0.3 μM to 3.5 mM, with B being present at 2.9-3.5 μM. For each element assayed, the concentration was higher in phloem exudate (1.6 μM to 91 mM) than in xylem sap; B was present at about 0.4 mM. Intact broccoli and lupin plants or detached transpiring broccoli shoots were supplied simultaneously with enriched 10 B, strontium (a xylem marker) and rubidium (a xylem/phloem marker) during early reproductive growth. The contents of these three compounds were determined in foliage and florets or fruits as a function of time (i.e. up to 12 h and 4 days for broccoli and lupin plants, respectively), and the content in florets or fruits was expressed as a percent of the total recovered. In general, the percent recovery of both 10 B and rubidium in florets or fruits was similar and markedly greater than that for strontium, even at the earliest harvest times (within 2 h for broccoli and 1 day for lupin). The data indicate that in plants with restricted B mobility, B is supplied to sink tissues in the phloem, and the extent of B xylem-to-phloem transfer is closely determined by current uptake. (au)

  18. p70S6 kinase signals cell survival as well as growth, inactivating the pro-apoptotic molecule BAD

    DEFF Research Database (Denmark)

    Harada, H; Andersen, Jens S.; Mann, M

    2001-01-01

    Cytokines often deliver simultaneous, yet distinct, cell growth and cell survival signals. The 70-kDa ribosomal protein S6 kinase (p70S6K) is known to regulate cell growth by inducing protein synthesis components. We purified membrane-based p70S6K as a kinase responsible for site-specific phospho...

  19. Individual growth and reproductive behavior in a newly established population of northern snakehead (Channa argus), Potomac River, USA

    Science.gov (United States)

    Landis, Andrew M. Gascho; Lapointe, Nicolas W. R.; Angermeier, Paul L.

    2010-01-01

    Northern snakehead (Channa argus) were first found in the Potomac River in 2004. In 2007, we documented feeding and reproductive behavior to better understand how this species is performing in this novel environment. From April to October, we used electrofishing surveys to collect data on growth, condition, and gonad weight of adult fish. Growth rates of young were measured on a daily basis for several weeks. Mean length-at-age for Potomac River northern snakehead was lower than for fish from China, Russia, and Uzbekistan. Fish condition was above average during spring and fall, but below average in summer. Below-average condition corresponded to periods of high spawning activity. Gonadosomatic index indicated that females began spawning at the end of April and continued through August. Peak spawning occurred at the beginning of June when average temperatures reached 26°C. Larval fish growth rate, after the transition to exogenous feeding, was 2.3 (SD ± 0.7) mm (total length, TL) per day. Although Potomac River northern snakehead exhibited lower overall growth rates when compared to other populations, these fish demonstrated plasticity in timing of reproduction and rapid larval growth rates. Such life history characteristics likely contribute to the success of northern snakehead in its new environment and limit managers’ options for significant control of its invasion.

  20. EG-VEGF controls placental growth and survival in normal and pathological pregnancies: case of fetal growth restriction (FGR).

    Science.gov (United States)

    Brouillet, S; Murthi, P; Hoffmann, P; Salomon, A; Sergent, F; De Mazancourt, P; Dakouane-Giudicelli, M; Dieudonné, M N; Rozenberg, P; Vaiman, D; Barbaux, S; Benharouga, M; Feige, J-J; Alfaidy, N

    2013-02-01

    Identifiable causes of fetal growth restriction (FGR) account for 30 % of cases, but the remainders are idiopathic and are frequently associated with placental dysfunction. We have shown that the angiogenic factor endocrine gland-derived VEGF (EG-VEGF) and its receptors, prokineticin receptor 1 (PROKR1) and 2, (1) are abundantly expressed in human placenta, (2) are up-regulated by hypoxia, (3) control trophoblast invasion, and that EG-VEGF circulating levels are the highest during the first trimester of pregnancy, the period of important placental growth. These findings suggest that EG-VEGF/PROKR1 and 2 might be involved in normal and FGR placental development. To test this hypothesis, we used placental explants, primary trophoblast cultures, and placental and serum samples collected from FGR and age-matched control women. Our results show that (1) EG-VEGF increases trophoblast proliferation ([(3)H]-thymidine incorporation and Ki67-staining) via the homeobox-gene, HLX (2) the proliferative effect involves PROKR1 but not PROKR2, (3) EG-VEGF does not affect syncytium formation (measurement of syncytin 1 and 2 and β hCG production) (4) EG-VEGF increases the vascularization of the placental villi and insures their survival, (5) EG-VEGF, PROKR1, and PROKR2 mRNA and protein levels are significantly elevated in FGR placentas, and (6) EG-VEGF circulating levels are significantly higher in FGR patients. Altogether, our results identify EG-VEGF as a new placental growth factor acting during the first trimester of pregnancy, established its mechanism of action, and provide evidence for its deregulation in FGR. We propose that EG-VEGF/PROKR1 and 2 increases occur in FGR as a compensatory mechanism to insure proper pregnancy progress.

  1. Growth and Survival of Larval Alewife (Alosa pseudoharengus) in Southern New England Lakes

    Science.gov (United States)

    Suca, J.; Jones, A.; Llopiz, J.

    2016-02-01

    Alewives (Alosa pseudoharengus) are ecologically and commercially important anadromous fish in eastern North America, and populations have declined to close to 1% of their historic levels. Despite moratoriums in recent years in most US states, there has been little recovery of alewives. In light of this poor recovery, we examined the factors that influence the survival of alewife larvae that were spawned in multiple freshwater systems in Massachusetts. Four lakes were sampled each week throughout the spring and summer for fish larvae, zooplankton and physicochemical parameters. Abundances of larvae from the lakes were analyzed, along with environmental factors. In the lab, otoliths of larvae from two different lakes were used for age and growth rate determination, as well as examining selective mortality during the larval period. Additionally, differences in growth and selective mortality of early and late spawned larvae were analyzed to investigate the tradeoffs between spawning early versus late in the spawning season. Abundances varied greatly between lakes and sampling times. Through otolith analysis, differences in growth rates between lakes were observed. This is likely due to differences in either temperature or food availability, and ongoing work quantifying zooplankton abundances will address these potential factors. Interestingly, there was no evidence for selective mortality in the two lakes examined, a result that is consistent with the hypothesis that anadromy in this species evolved as a strategy to minimize predation during the vulnerable larval period.

  2. The impact of polyphenols on chondrocyte growth and survival: a preliminary report

    Directory of Open Access Journals (Sweden)

    Salvador Fernández-Arroyo

    2015-10-01

    Full Text Available Background: Imbalances in the functional binding of fibroblast growth factors (FGFs to their receptors (FGFRs have consequences for cell proliferation and differentiation that in chondrocytes may lead to degraded cartilage. The toxic, proinflammatory, and oxidative response of cytokines and FGFs can be mitigated by dietary polyphenols. Objective: We explored the possible effects of polyphenols in the management of osteoarticular diseases using a model based on the transduction of a mutated human FGFR3 (G380R in murine chondrocytes. This mutation is present in most cases of skeletal dysplasia and is responsible for the overexpression of FGFR3 that, in the presence of its ligand, FGF9, results in toxic effects leading to altered cellular growth. Design: Different combinations of dietary polyphenols derived from plant extracts were assayed in FGFR3 (G380R mutated murine chondrocytes, exploring cell survival, chloride efflux, extracellular matrix (ECM generation, and grade of activation of mitogen-activated protein kinases. Results: Bioactive compounds from Hibiscus sabdariffa reversed the toxic effects of FGF9 and restored normal growth, suggesting a probable translation to clinical requests in humans. Indeed, these compounds activated the intracellular chloride efflux, increased ECM generation, and stimulated cell proliferation. The inhibition of mitogen-activated protein kinase phosphorylation was interpreted as the main mechanism governing these beneficial effects. Conclusions: These findings support the rationale behind the encouragement of the development of drugs that repress the overexpression of FGFRs and suggest the dietary incorporation of supplementary nutrients in the management of degraded cartilage.

  3. Growth and survival of Escherichia coli and enterococci populations in the macro-alga Cladophora (Chlorophyta).

    Science.gov (United States)

    Byappanahalli, Muruleedhara N; Shively, Dawn A; Nevers, Meredith B; Sadowsky, Michael J; Whitman, Richard L

    2003-11-01

    The macro-alga Cladophora glomerata is found in streams and lakes worldwide. High concentrations of Escherichia coli and enterococci have been reported in Cladophora along the Lake Michigan shore. The objective of this study was to determine if Cladophora supported growth of these indicator bacteria. Algal leachate readily supported in vitro multiplication of E. coli and enterococci, suggesting that leachates contain necessary growth-promoting substances. Growth was directly related to the concentration of algal leachate. E. coli survived for over 6 months in dried Cladophora stored at 4 degrees C; residual E. coli grew after mat rehydration, reaching a carrying capacity of 8 log CFU g(-1) in 48 h. Results of this study also show that the E. coli strains associated with Cladophora are highly related; in most instances they are genetically different from each other, suggesting that the relationship between E. coli and Cladophora may be casual. These findings indicate that Cladophora provides a suitable environment for indicator bacteria to persist for extended periods and to grow under natural conditions.

  4. Analysis of growth behavior of survived microorganisms from decontaminated spices within meat products

    International Nuclear Information System (INIS)

    Furuta, Masakazu; Ishikawa, Etsuko; Hoshina, Miyuki; Tomii, Enami; Koike, Kazuko; Ukai, Mitsuko

    2010-01-01

    The purpose of the study is to investigate the condition of microbial growth recovery from the damage of killing stresses such as heating and 60 Co-gamma irradiation especially within the processed meat products. Black pepper powder treated by each process in which less than 1000 microbial loads was enumerated by aerobic counts was mixed with minced sausage and incubated at 30degC for several days. Outgrowth of microorganism was monitored according to the procedure described by Japanese Food Hygiene Law. Sausage samples containing the treated black pepper powder showed the similar microbial growth from less than 1000 CFU/g of the sample to approximately the order of 10 9 CPU/g of the sample during the incubation at 30degC, irrespective of gamma-irradiation or superheated-steam treatment. There were no significant differences between gamma-irradiation and superheated-steam treatment in outgrowth of the surviving microorganisms when the treated black pepper or sage was mixed and pulverized with sausage. In case paprika, growth delay of the super-steamed survivors was observed within 1 day after incubation. (author)

  5. Survival of the Best Fit: Competition from Low Wage Countries and the (Uneven) Growth of US Manufacturing Plants

    OpenAIRE

    Andrew B. Bernard; J. Bradford Jensen; Peter K. Schott

    2002-01-01

    We examine the relationship between import competition from low wage countries and the reallocation of US manufacturing from 1977 to 1997. Both employment and output growth are slower for plants that face higher levels of low wage import competition in their industry. As a result, US manufacturing is reallocated over time towards industries that are more capital and skill intensive. Differential growth is driven by a combination of increased plant failure rates and slower growth of surviving ...

  6. Dairy herd mastitis and reproduction: using simulation to aid interpretation of results from discrete time survival analysis.

    Science.gov (United States)

    Hudson, Christopher D; Bradley, Andrew J; Breen, James E; Green, Martin J

    2015-04-01

    Probabilistic sensitivity analysis (PSA) is a simulation-based technique for evaluating the relative importance of different inputs to a complex process model. It is commonly employed in decision analysis and for evaluation of the potential impact of uncertainty in research findings on clinical practice, but has a wide variety of other possible applications. In this example, it was used to evaluate the association between herd-level udder health and reproductive performance in dairy herds. Although several recent studies have found relatively large associations between mastitis and fertility at the level of individual inseminations or lactations, the current study demonstrated that herd-level intramammary infection status is highly unlikely to have a clinically significant impact on the overall reproductive performance of a dairy herd under typical conditions. For example, a large increase in incidence rate of clinical mastitis (from 92 to 131 cases per 100 cows per year) would be expected to increase a herd's modified FERTEX score (a cost-based measure of overall reproductive performance) by just £4.50(1) per cow per year. The herd's background level of submission rate (proportion of eligible cows served every 21 days) and pregnancy risk (proportion of inseminations leading to a pregnancy) correlated strongly with overall reproductive performance and explained a large proportion of the between-herd variation in performance. PSA proved to be a highly useful technique to aid understanding of results from a complex statistical model, and has great potential for a wide variety of applications within the field of veterinary science. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Does the silver moss Bryum argenteum exhibit sex-specific patterns in vegetative growth rate, asexual fitness or prezygotic reproductive investment?

    Science.gov (United States)

    Horsley, Kimberly; Stark, Lloyd R; McLetchie, D Nicholas

    2011-05-01

    Expected life history trade-offs associated with sex differences in reproductive investment are often undetected in seed plants, with the difficulty arising from logistical issues of conducting controlled experiments. By controlling genotype, age and resource status of individuals, a bryophyte was assessed for sex-specific and location-specific patterns of vegetative, asexual and sexual growth/reproduction across a regional scale. Twelve genotypes (six male, six female) of the dioecious bryophyte Bryum argenteum were subcultured to remove environmental effects, regenerated asexually to replicate each genotype 16 times, and grown over a period of 92 d. Plants were assessed for growth rates, asexual and sexual reproductive traits, and allocation to above- and below-ground regenerative biomass. The degree of sexual versus asexual reproductive investment appears to be under genetic control, with three distinct ecotypes found in this study. Protonemal growth rate was positively correlated with asexual reproduction and sexual reproduction, whereas asexual reproduction was negatively correlated (appeared to trade-off) with vegetative growth (shoot production). No sex-specific trade-offs were detected. Female sex-expressing shoots were longer than males, but the sexes did not differ in growth traits, asexual traits, sexual induction times, or above- and below-ground biomass. Males, however, had much higher rates of inflorescence production than females, which translated into a significantly higher (24x) prezygotic investment for males relative to females. Evidence for three distinct ecotypes is presented for a bryophyte based on regeneration traits. Prior to zygote production, the sexes of this bryophyte did not differ in vegetative growth traits but significantly differed in reproductive investment, with the latter differences potentially implicated in the strongly biased female sex ratio. The disparity between males and females for prezygotic reproductive investment is

  8. Proteomic analysis reveals the mechanisms of Mycena dendrobii promoting transplantation survival and growth of tissue culture seedlings of Dendrobium officinale.

    Science.gov (United States)

    Xu, X B; Ma, X Y; Lei, H H; Song, H M; Ying, Q C; Xu, M J; Liu, S B; Wang, H Z

    2015-06-01

    Dendrobium officinale is an important traditional Chinese medicinal herb. Its seedlings generally show low survival and growth when transferred from in vitro tissue culture to a greenhouse or field environment. In this study, the effect of Mycena dendrobii on the survival and growth of D. officinale tissue culture seedlings and the mechanisms involved was explored. Mycena dendrobii were applied underneath the roots of D. officinale tissue culture seedlings. The seedling survival and growth were analysed. The root proteins induced by M. dendrobii were identified using two-dimensional (2-D) electrophoresis and matrix-assisted laser desorption/ionization time-of-flight MS (MALDI-TOF-MS). Mycena dendrobii treatment significantly enhanced survival and growth of D. officinale seedlings. Forty-one proteins induced by M. dendrobii were identified. Among them, 10 were involved in defence and stress response, two were involved in the formation of root or mycorrhizae, and three were related to the biosynthesis of bioactive constituents. These results suggest that enhancing stress tolerance and promoting new root formation induced by M. dendrobii may improve the survival and growth of D. officinale tissue culture seedlings. This study provides a foundation for future use of M. dendrobii in the large-scale cultivation of Dendrobiums. © 2015 The Society for Applied Microbiology.

  9. Nutritional intra-amniotic therapy increases survival in a rabbit model of fetal growth restriction

    Science.gov (United States)

    Illa, Miriam; Pla, Laura; Zamora, Monica; Crispi, Fatima; Gratacos, Eduard

    2018-01-01

    Objective To evaluate the perinatal effects of a prenatal therapy based on intra-amniotic nutritional supplementation in a rabbit model of intrauterine growth restriction (IUGR). Methods IUGR was surgically induced in pregnant rabbits at gestational day 25 by ligating 40–50% of uteroplacental vessels of each gestational sac. At the same time, modified-parenteral nutrition solution (containing glucose, amino acids and electrolytes) was injected into the amniotic sac of nearly half of the IUGR fetuses (IUGR-T group n = 106), whereas sham injections were performed in the rest of fetuses (IUGR group n = 118). A control group without IUGR induction but sham injection was also included (n = 115). Five days after the ligation procedure, a cesarean section was performed to evaluate fetal cardiac function, survival and birth weight. Results Survival was significantly improved in the IUGR fetuses that were treated with intra-amniotic nutritional supplementation as compared to non-treated IUGR animals (survival rate: controls 71% vs. IUGR 44% p = 0.003 and IUGR-T 63% vs. IUGR 44% p = 0.02), whereas, birth weight (controls mean 43g ± SD 9 vs. IUGR 36g ± SD 9 vs. IUGR-T 35g ± SD 8, p = 0.001) and fetal cardiac function were similar among the IUGR groups. Conclusion Intra-amniotic injection of a modified-parenteral nutrient solution appears to be a promising therapy for reducing mortality among IUGR. These results provide an opportunity to develop new intra-amniotic nutritional strategies to reach the fetus by bypassing the placental insufficiency. PMID:29466434

  10. Survival and growth of catfish Pangasionodon sp. larvae fed on vitamin C-enriched Artemia

    Directory of Open Access Journals (Sweden)

    Mia Setiawati

    2015-05-01

    Full Text Available ABSTRACT The research was conducted to evaluate effect of the administration of Artemia enriched with vitamin C on the survival, total body length, and average body weight of Pangasionodon sp. larvae. Artemia were enriched with either 0, 50, 100, or 150 mg/L vitamin C immersed in the culture medium for 13 hours. Two days old larvae were fed on enriched Artemia 12 times/day for seven days. At the end of feeding experiment, it was found that fish fed on Artemia enriched with 100 mg/L culture medium had the highest survival, total length and body weight, respectively 76.17±12.78%, 1.63±0.34 cm, and 20.6±3.8 mg. Keywords: survival, growth, Artemia, vitamin C, catfish, Pangasionodon sp.  ABSTRAK Penelitian ini dilakukan untuk mengetahui pengaruh Artemia yang diperkaya dengan vitamin C dosis berbeda terhadap kelangsungan hidup, panjang total, dan bobot tubuh larva ikan patin Pangasionodon sp. Pada penelitian ini, Artemia diperkaya dengan vitamin C dosis 0, 50, 100, atau 150 mg/L media pengayaan. Larva yang berumur dua hari diberi pakan Artemia hasil pengayaan sebanyak 12 kali sehari selama tujuh hari masa pemeliharaan. Pada akhir percobaan, didapatkan bahwa larva ikan yang diberi Artemia diperkaya vitamin C dosis 100 mg/L media pengayaan memberikan kelangsungan hidup 76,17±12,78%, panjang total 1,63±0,34 cm, dan bobot tubuh paling tinggi 20,6±3,8 mg. Kata kunci: kelangsungan hidup, pertumbuhan, Artemia, vitamin C, ikan patin, Pangasionodon sp. 

  11. Growth and survival of silver catfish larvae, Rhamdia quelen (Heptapteridae, at different calcium and magnesium concentrations

    Directory of Open Access Journals (Sweden)

    Lenise Vargas Flores da Silva

    Full Text Available Since the relative ratios of Ca2+ and Mg2+ can vary greatly from one water body to another, and lime used for the increase of water hardness or pH can have different ratios of Ca2+ and Mg2+ in its composition, the objective of this study was to analyze the growth and survival of silver catfish, Rhamdia quelen, larvae at different calcium and magnesium concentrations. After fertilization, eggs were randomly divided into 4 treatments (three replicates per treatment with different concentrations of Ca2+ and Mg2+ at hardness values of 70 mg.L-1 CaCO3 (mg.L-1 : 5.2 Ca2+ and 14.12 Mg2+; 13.11 Ca2+ and 7.11 Mg2+; 20.26 Ca2+ and 2.86 Mg2+; 24.95 Ca2+ and 0.95 Mg2+ and 150 mg.L-1 CaCO3 (mg.L-1 : 5.2 Ca2+ and 32.70 Mg2+; 28.63 Ca2+ and 16.44 Mg2+; 44.68 Ca2+and 6.44 Mg2+; 62.78 Ca2+ and 0.95 Mg2+. There was also another group exposed to water hardness of 20 mg.L-1 CaCO3 (Ca2+ 5.2 mg.L-1 and Mg2+ 0.95 mg.L-1 at both experiments. The post-hatch larvae were transferred to continuously aerated 40 L polyethylene aquaria (400 larvae/tank containing the same water as used for incubation. Samples of larvae were collected on days 0, 7, 14, and 21, and the length, weight, and specific growth rate were determined for each collection. Survival and biomass were calculated on day 21. At water hardness of 70 mg.L-1 CaCO3, the best survival and growth of silver catfish larvae was observed at water with 20.26 mg.L-1 Ca2+ and 2.89 mg.L-1 Mg2+, with similar results to the group exposed to water hardness of 20 mg.L-1 CaCO3. However, compared to the group exposed to water hardness of 20 mg.L-1 CaCO3, survival and growth were lower at 150 mg.L-1 CaCO3. Therefore, a hardness range of 20 to 70 mg.L-1 CaCO3 is recommended for silver catfish larviculture, but with 20.26 mg.L-1 Ca2+ and 2.89 mg.L-1 Mg2+ at 70 mg.L-1 CaCO3. Water hardness of 150 mg.L-1 CaCO3 is not recommended for this species.

  12. Survival Rate and Growth of Fighting Fish Larvae (Betta splendens Regan Fed on Various Live Foods

    Directory of Open Access Journals (Sweden)

    T. Budiardi

    2007-01-01

    Full Text Available Larval of fighting fish (Betta splendens Regan requires precise live foods for its growth and survival. In this experiment, fish larvae were fed on either Paramecium + Artemia, Paramecium + Artemia + Tubifex, Paramecium + Moina, or Paramecium + Moina + Tubifex. The fish were fed Paramecium from day-2 till day-7 after hatching. There after, the live food was changed according to the treatments till day-28.  Results showed that fish fed on Paramecium + Artemia significantly had the highest total length (12.63 mm than other treatments (11.86 mm. On the other hand, survival rate of fish had no significant affected by the treatments. Keywords: fighting fish, Betta splendens, Paramecium, Moina, Artemia, Tubifex, larvae   ABSTRAK Larva ikan betta (Betta splendens Regan membutuhkan jenis pakan alami yang tepat bagi kelangsungan hidup dan pertumbuhannya. Pada penelitian ini, larva ikan diberi pakan berupa Paramecium + Artemia, Paramecium + Artemia + Tubifex, Paramecium + Moina, atau Paramecium + Moina + Tubifex.  Ikan diberi pakan pakan berupa Paramecium dari hari ke-2 hingga hari ke-7. Setelah itu, pemberian pakan alami diubah berdasarkan masing-masing perlakuan hingga hari ke-28.  Hasil penelitian menunjukkan bahwa ikan yang diberi pakan Paramecium + Artemia memiliki tubuh secara signifikan lebih panjang (12,63 mm dibandingkan perlakuan lainnya (11,86 mm.  Sementara itu, kelangsungan hidup tidak dipengatuhi oleh perlakuan. Kata kunci: ikan betta, Betta splendens, Paramecium, Moina, Artemia, Tubifex, larva

  13. Halophilic archaea on Earth and in space: growth and survival under extreme conditions.

    Science.gov (United States)

    Oren, Aharon

    2014-12-13

    Salts are abundant on Mars, and any liquid water that is present or may have been present on the planet is expected to be hypersaline. Halophilic archaea (family Halobacteriaceae) are the microorganisms best adapted to life at extremes of salinity on Earth. This paper reviews the properties of the Halobacteriaceae that may make the group good candidates for life also on Mars. Many species resist high UV and gamma radiation levels; one species has survived exposure to vacuum and radiation during a space flight; and there is at least one psychrotolerant species. Halophilic archaea may survive for millions of years within brine inclusions in salt crystals. Many species have different modes of anaerobic metabolism, and some can use light as an energy source using the light-driven proton pump bacteriorhodopsin. They are also highly tolerant to perchlorate, recently shown to be present in Martian soils, and some species can even use perchlorate as an electron acceptor to support anaerobic growth. The presence of characteristic carotenoid pigments (α-bacterioruberin and derivatives) makes the Halobacteriaceae easy to identify by Raman spectroscopy. Thus, if present on Mars, such organisms may be detected by Raman instrumentation planned to explore Mars during the upcoming ExoMars mission. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  14. Effect of Salinity Adaptation Technique on Survival and Growth Rate of Patin Catfish, Pangasius sp.

    Directory of Open Access Journals (Sweden)

    K. Nirmala

    2007-01-01

    Full Text Available This study was carried out to determine the effect of salinity adaptation techniques on growth and survival of patin catfish Pangasius sp. fry.  Fry of 1.5-2.0 inch in length were reared in the water with different of the initial salinity of 1, 2, 3, 4 and 5 ppt.  Salinity was then daily increased by duplicated the initial water salinity until fish died.  The results of study showed that fry could survive by initial salinity adaptation of 1 ppt and then increasing the salinity by 1 ppt/day to reach 27 ppt.  In the other treatments, all fry died after the salinity reach 18-25 ppt. Keywords: patin catfish, Pangasius, adaptation, salinity   ABSTRAK Penelitian ini bertujuan untuk mengetahui pengaruh teknik adaptasi salinitas terhadap pertumbuhan dan kelangsungan hidup benih ikan patin Pangasius sp.  Benih patin ukuran 1,5-2 inci dipelihara pada salinitas awal berbeda, yaitu 1, 2, 3, 4 dan 5 ppt. Salinitas air pemeliharaan ditingkatkan kelipatan dari salinitas awal setiap hari hingga ikan mati.  Hasil penelitian menunjukkan bahwa adaptasi salinitas awal 1 ppt dan peningkatan sebesar 1ppt/hari menyebabkan ikan dapat bertahan hidup sampai pada salinitas 27 ppt. Pada perlakuan lainnya, benih ikan mengalami kematian masal ketika salinitas mencapai 18-25 ppt. Kata kunci: ikan patin, Pangasius, adaptasi, salinitas

  15. Surviving starvation: essential role of the ghrelin-growth hormone axis.

    Science.gov (United States)

    Goldstein, J L; Zhao, T-j; Li, R L; Sherbet, D P; Liang, G; Brown, M S

    2011-01-01

    After brief starvation, vertebrates maintain blood glucose by releasing fatty acids from adipose tissue. The fatty acids provide energy for gluconeogenesis in liver and are taken up by muscle, sparing glucose. After prolonged starvation, fat stores are depleted, yet blood glucose can be maintained at levels sufficient to preserve life. Using a new mouse model, we demonstrate that survival after prolonged starvation requires ghrelin, an octanoylated peptide hormone that stimulates growth hormone (GH) secretion. We studied wild-type mice and mice lacking ghrelin as a result of knockout of GOAT, the enzyme that attaches octanoate to ghrelin. Mice were fed 40% of their normal intake for 7 d. Fat stores in both lines of mice became depleted after 4 d. On day 7, mice were fasted for 23 h. In wild-type mice, ghrelin and GH rose massively, and blood sugar was maintained at ~60 mg/dL. In Goat(-/-) mice, ghrelin was undetectable and GH failed to rise appropriately. Blood sugar declined to ~20 mg/dL, and the animals were moribund. Infusion of ghrelin or GH prevented hypoglycemia. Our results support the following sequence: (1) Starvation lowers blood glucose; (2) glucose-sensing neurons respond by activating sympathetic neurons; (3) norepinephrine, released in the stomach, stimulates ghrelin secretion; (4) ghrelin releases GH, which maintains blood glucose. Thus, ghrelin lies at the center of a hormonal response that permits mice to survive an acute fast superimposed on chronic starvation.

  16. Survival and growth of wildlife shrubs and trees on acid mine spoil

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, D.K.; Adkisson, L.F.

    1980-01-01

    The purpose of this study was to assess the survival and growth of selected wildlife plants over a wide range of acid mine spoil conditions and to identify species suitable for surface mine reclamation. A major criterion in selection of study sites was inclusion of a wide range of spoil acidity conditions. The Ollis Creek (Study Area A) and Farrell (Study Area B) coal surface mines located in Campbell and Scott Counties, Tennessee, were selected for study. Seven plant species, all of which had been used in past reclamation demonstrations, were introduced on the 22 plots during March 1972. Autumn olive (Elaeagnus umbellata) was included as a control plant. Ten additional plant species were introduced during March 1973. With the exception of highbush blueberry (Vaccinium corymbosum var.). European filbert (Corylus avellana), and red maple (Acer rubrum), these species had not been used in TVA reclamation demonstrations. To assess the effects of spoil pH on the plants, the plots were grouped into seven pH categories, and mean percent survival and growth for each species were calculated. Results indicate that autumn olive, elaeagnus cherry, arnot locust, sawtooth oak, red maple, and Toringo crabapple are suitable for quick improvement of surface mine habitat over a wide range of spoil acidity in the Appalachian coalfield. Bessey cherry and European filbert need further study before a decision can be made regarding their reclamation utility. Species that are not recommended for quick habitat improvement over a wide range of surface mine spoil pH conditions include bush honeysuckle, barberry, Siberian crabapple, Manchu cherry, American beautyberry, bear oak, blueberry, rem-red honeysuckle, and redcedar.

  17. Fibulin-1 Binds to Fibroblast Growth Factor 8 with High Affinity: EFFECTS ON EMBRYO SURVIVAL.

    Science.gov (United States)

    Fresco, Victor M; Kern, Christine B; Mohammadi, Moosa; Twal, Waleed O

    2016-09-02

    Fibulin-1 (FBLN1) is a member of a growing family of extracellular matrix glycoproteins that includes eight members and is involved in cellular functions such as adhesion, migration, and differentiation. FBLN1 has also been implicated in embryonic heart and valve development and in the formation of neural crest-derived structures, including aortic arch, thymus, and cranial nerves. Fibroblast growth factor 8 (FGF8) is a member of a large family of growth factors, and its functions include neural crest cell (NCC) maintenance, specifically NCC migration as well as patterning of structures formed from NCC such as outflow tract and cranial nerves. In this report, we sought to investigate whether FBLN1 and FGF8 have cooperative roles in vivo given their influence on the development of the same NCC-derived structures. Surface plasmon resonance binding data showed that FBLN1 binds tightly to FGF8 and prevents its enzymatic degradation by ADAM17. Moreover, overexpression of FBLN1 up-regulates FGF8 gene expression, and down-regulation of FBLN1 by siRNA inhibits FGF8 expression. The generation of a double mutant Fbln1 and Fgf8 mice (Fbln1(-/-) and Fgf8(-/-)) showed that haplo-insufficiency (Fbln1(+/-) and Fgf8(+/-)) resulted in increased embryonic mortality compared with single heterozygote crosses. The mortality of the FGF8/Fbln1 double heterozygote embryos occurred between 14.5 and 16.5 days post-coitus. In conclusion, FBLN1/FGF8 interaction plays a role in survival of vertebrate embryos, and reduced levels of both proteins resulted in added mortality in utero The FBLN1/FGF8 interaction may also be involved in the survival of neural crest cell population during development. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  18. Growth, mortality and reproduction of the blue tilapia Oreochromis aureus (Perciformes: Cichlidae in the Aguamilpa Reservoir, Mexico

    Directory of Open Access Journals (Sweden)

    Emilio Peña Messina

    2010-12-01

    Full Text Available Tilapia production has increased in Aguamilpa Reservoir, in Nayarit, Mexico, in the last few years and represents a good economic activity for rural communities and the country. We determined growth parameters, mortality and reproductive aspects for 2 413 specimens of blue tilapia Oreochromis aureus in this reservoir. Samples were taken monthly from July 2000 through June 2001, of which 1 371 were males and 1 042 were females. Standard length (SL and total weight (TW were measured in each organism. The SL/TW relationships through power models for sexes were determined. The growth parameters L ∞, k, and t0 of the von Bertalanffy equation were estimated using frequency distribution of length through ELEFAN-I computer program. Finally the reproductive cycle and size of first maturity were established using morph chromatic maturity scale. The results suggested that the males and females had negative allometric growth (b<3. Significant differences were found between SL/TW model for the sexes, suggesting separate models for males and females. Results indicate that there are no differences in growth rates between sexes; the proposed parameters were L∞=43.33cm standard length, k=0.36/year and t0=-0.43years. Natural and fishing mortality coefficients were 0.83/year and 1.10/year, respectively. The estimated exploitation rate (0.57/year suggested that during the study period the fishery showed signs of overfishing. Blue tilapia reproduces year-round; the highest activity occurs from January through May and size of first maturity was 23cm SL. We conclude that it is necessary to establish a minimum catch size in this reservoir based on the reproductive behavior of this species. Rev. Biol. Trop. 58 (4: 1577-1586. Epub 2010 December 01.

  19. Reproduction traits, growth traits and age at first calving in Holstein heifers

    Directory of Open Access Journals (Sweden)

    Bruna Silva Marestone

    2014-02-01

    Full Text Available The objective of this study was to verify the reproductive efficiency expressed by traits, interval from first to second calving (IDP, number of services per conception to the first calving (NSC1, number of services per conception for the second calving (NSC2, service period from the first to the second calving (PS and gestation lenght (PG of Holstein heifers. Data from 377 heifers from two herds, one in Santa Cruz do Rio Pardo, São Paulo and another in Rolândia, Paraná were analysed. The statistical model to analyze IDP, NSC1, NSC2, PS and PG included the fixed effect of Contemporary Group (CG. To analyze PG, it was also considered the effect of calf sex. To evaluate the growth performance and age at first calving (AFC, data from 360 Holstein heifers belonging to property in Rolândia were analysed. The model included the fixed effects of contemporary groups (CG and average daily gain from birth to 15 months (ADG. A similar model was used to analyze weigth at 458 dias (W458 and ADG, therefore considering only CG. The overall means of IDP, NSC1, NSC2, PS and PG, were 14.96 ± 3.94 months; 1.35 ± 0.71 services, 2.86 ± 2.37 services, 178.83 ± 118.73 days; 276.67± 5.65 days, respectively. Correlations were observed between the traits IDP and NSC2 of 72% (P<0.0001, between IDP and PS of 98% (P<0.0001 and between NCS2 and PS of 72% (P<0.0001. The gestation length of males and females showed estimated average of 277.53 ± 0.46 days and 276.33 ± 0.40 days, respectively, and the calf sex was source of variation on PG (P<0.05. Average daily gain was a significant source of variation on AFC and CG affected all traits studied. The estimated average for AFC was 24.18 ± 1.59 months, for W458 was 362.33 ± 36.24 kg and ADG was 0.704 ± 0.08 kg.

  20. Baseline growth and reproductive parameters in Lymnaea stagnalis for OECD test guideline development: optimization of diets and culturing conditions

    DEFF Research Database (Denmark)

    Holbech, Henrik; Hutchinson, Tom

    laboratories in Denmark, Germany and the UK for the OECD pre-validation work to date. Laboratory cultures of L. stagnalis are traditionally fed fresh (preferably organic) lettuce; however, interrupted supplies of fresh lettuce in some countries in 2011 highlighted a potential problem for the draft OECD test...... of a mollusc reproduction test guideline. An ad hoc mollusc expert group has been formed in Europe to validate methods that can meet this need. Currently, a key species for use in this context is the freshwater gastropod Lymnaea stagnalis. An important aspect of this work is to first develop a specific...... pathogen free defined strain of L. stagnalis and second to establish a historical database of growth and reproductive rates under defined culturing conditions. A mass culture of the RENILYS® strain of L. stagnalis have been established at INRA (France) since 2002 and has been distributed to research...

  1. The role of insulin-like growth factor-1 (IGF-1) in growth and reproduction in female brown house snakes (Lamprophis fuliginosus).

    Science.gov (United States)

    Sparkman, A M; Byars, D; Ford, N B; Bronikowski, A M

    2010-09-15

    Insulin-like growth factor-1 (IGF-1) is a peptide hormone critically involved in the regulation of key life-history traits such as growth and reproduction. Its structure and function are well-characterized among diverse mammal, fish, and bird species; however, little is known regarding the activities of IGF-1 in non-avian reptiles, particularly snakes and lizards. Nevertheless, several unique characteristics of reptiles, such as high metabolic flexibility and remarkable diversity in life-history strategy, suggest that they are of great interest in the study of endocrinological mechanisms underlying the regulation and evolution of life-history traits. Here we test for a relationship between IGF-1 and individual feeding rate, growth rate and reproductive stage in lab-reared female offspring of wild-caught oviparous house snakes, Lamprophis fuliginosus. We confirm a positive correlation between IGF-1 and both feeding and growth rates in sexually immature snakes, similar to that reported in other taxa. We also show a family effect on IGF-1, suggesting that IGF-1 levels may be heritable in these snakes, and serve as an important target of selection to produce divergent life-history strategies. Furthermore, we provide evidence that suggests that IGF-1 may peak rapidly after first mating, and subsequently decline prior to egg-laying, a phenomenon not previously reported in other taxa. These findings suggest that further comparative study of IGF-1 in snakes may reveal both the extent to which IGF-1 function is conserved across major taxonomic groups, as well as novel and intriguing roles for IGF-1 in the regulation of reproductive activities. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  2. Variations in growth, survival and carbon isotope composition (delta(13)C) among Pinus pinaster populations of different geographic origins.

    Science.gov (United States)

    Correia, Isabel; Almeida, Maria Helena; Aguiar, Alexandre; Alía, Ricardo; David, Teresa Soares; Pereira, João Santos

    2008-10-01

    To evaluate differences in growth and adaptability of maritime pine (Pinus pinaster Ait.), we studied growth, polycyclism, needle tissue carbon isotope composition (delta(13)C) as an estimate of water-use efficiency (WUE) and survival of seven populations at 10 years of age growing in a performance trial at a provenance test site in Escaroupim, Portugal. Six populations were from relatively high rainfall sites in Portugal and southwestern France (Atlantic group), and one population was from a more arid Mediterranean site in Spain. There were significant differences between some populations in total height, diameter at breast height, delta(13)C of bulk needle tissue, polycyclism and survival. A population from central Portugal (Leiria, on the Atlantic coast) was the tallest and had the lowest delta(13)C. Overall, the variation in delta(13)C was better explained by the mean minimum temperatures of the coldest month than by annual precipitation at the place of origin. Analyses of the relationships between delta(13)C and growth or survival revealed a distinct pattern for the Mediterranean population, with low delta(13)C (and WUE) associated with the lowest growth potential and reduced survival. There were significant negative correlations between delta(13)C and height or survival in the Atlantic group. Variation in polycyclism was correlated with annual precipitation at the place of origin. Some Atlantic populations maintained a high growth potential while experiencing moderate water stress. A detailed knowledge of the relationships between growth, survival and delta(13)C in contrasting environments will enhance our ability to select populations for forestry or conservation.

  3. Sphingosine kinase-1 is central to androgen-regulated prostate cancer growth and survival.

    Directory of Open Access Journals (Sweden)

    Audrey Dayon

    Full Text Available BACKGROUND: Sphingosine kinase-1 (SphK1 is an oncogenic lipid kinase notably involved in response to anticancer therapies in prostate cancer. Androgens regulate prostate cancer cell proliferation, and androgen deprivation therapy is the standard of care in the management of patients with advanced disease. Here, we explored the role of SphK1 in the regulation of androgen-dependent prostate cancer cell growth and survival. METHODOLOGY/PRINCIPAL FINDINGS: Short-term androgen removal induced a rapid and transient SphK1 inhibition associated with a reduced cell growth in vitro and in vivo, an event that was not observed in the hormono-insensitive PC-3 cells. Supporting the critical role of SphK1 inhibition in the rapid effect of androgen depletion, its overexpression could impair the cell growth decrease. Similarly, the addition of dihydrotestosterone (DHT to androgen-deprived LNCaP cells re-established cell proliferation, through an androgen receptor/PI3K/Akt dependent stimulation of SphK1, and inhibition of SphK1 could markedly impede the effects of DHT. Conversely, long-term removal of androgen support in LNCaP and C4-2B cells resulted in a progressive increase in SphK1 expression and activity throughout the progression to androgen-independence state, which was characterized by the acquisition of a neuroendocrine (NE-like cell phenotype. Importantly, inhibition of the PI3K/Akt pathway--by negatively impacting SphK1 activity--could prevent NE differentiation in both cell models, an event that could be mimicked by SphK1 inhibitors. Fascinatingly, the reversability of the NE phenotype by exposure to normal medium was linked with a pronounced inhibition of SphK1 activity. CONCLUSIONS/SIGNIFICANCE: We report the first evidence that androgen deprivation induces a differential effect on SphK1 activity in hormone-sensitive prostate cancer cell models. These results also suggest that SphK1 activation upon chronic androgen deprivation may serve as a

  4. Radiosensitivity of different human tumor cells lines grown as multicellular spheroids determined from growth curves and survival data

    International Nuclear Information System (INIS)

    Schwachoefer, J.H.C.; Crooijmans, R.P.; van Gasteren, J.J.; Hoogenhout, J.; Jerusalem, C.R.; Kal, H.B.; Theeuwes, A.G.

    1989-01-01

    Five human tumor cell lines were grown as multicellular tumor spheroids (MTS) to determine whether multicellular tumor spheroids derived from different types of tumors would show tumor-type dependent differences in response to single-dose irradiation, and whether these differences paralleled clinical behavior. Multicellular tumor spheroids of two neuroblastoma, one lung adenocarcinoma, one melanoma, and a squamous cell carcinoma of the oral tongue, were studied in terms of growth delay, calculated cell survival, and spheroid control dose50 (SCD50). Growth delay and cell survival analysis for the tumor cell lines showed sensitivities that correlated well with clinical behavior of the tumor types of origin. Similar to other studies on melanoma multicellular tumor spheroids our spheroid control dose50 results for the melanoma cell line deviated from the general pattern of sensitivity. This might be due to the location of surviving cells, which prohibits proliferation of surviving cells and hence growth of melanoma multicellular tumor spheroids. This study demonstrates that radiosensitivity of human tumor cell lines can be evaluated in terms of growth delay, calculated cell survival, and spheroid control dose50 when grown as multicellular tumor spheroids. The sensitivity established from these evaluations parallels clinical behavior, thus offering a unique tool for the in vitro analysis of human tumor radiosensitivity

  5. Growth and survival of Salmonella in ground black pepper (Piper nigrum).

    Science.gov (United States)

    Keller, Susanne E; VanDoren, Jane M; Grasso, Elizabeth M; Halik, Lindsay A

    2013-05-01

    A four serovar cocktail of Salmonella was inoculated into ground black pepper (Piper nigrum) at different water activity (aw) levels at a starting level of 4-5 log cfu/g and incubated at 25 and at 35 °C. At 35 °C and aw of 0.9886 ± 0.0006, the generation time in ground black pepper was 31 ± 3 min with a lag time of 4 ± 1 h. Growth at 25 °C had a longer lag, but generation time was not statistically different from growth at 35 °C. The aw threshold for growth was determined to be 0.9793 ± 0.0027 at 35 °C. To determine survival during storage conditions, ground black pepper was inoculated at approximately 8 log cfu/g and stored at 25 and 35 °C at high (97% RH) and ambient (≤40% RH) humidity. At high relative humidity, aw increased to approximately 0.8-0.9 after approximately 20 days at both temperatures and no Salmonella was detected after 100 and 45 days at 25 and 35 °C, respectively. Under ambient humidity, populations showed an initial decrease of 3-4 log cfu/g, then remained stable for over 8 months at 25 and 35 °C. Results of this study indicate Salmonella can readily grow at permissive aw in ground black pepper and may persist for an extended period of time under typical storage conditions. Published by Elsevier Ltd.

  6. Associated fauna and effects of epibiotic barnacles on the relative growth and reproductive indices of Stramonita haemastoma (Gastropoda: Muricidae

    Directory of Open Access Journals (Sweden)

    Tahani El Ayari

    2015-06-01

    Full Text Available To better understand the impacts of biofouling on the biological processes of the basibiont, the effects of epibiotic barnacles on the relative growth and reproductive indices of Stramonita haemastoma (Linnaeus, 1767 were assessed. A total of 1035 specimens were collected monthly for one year from Bizerta Channel (northern Tunisia. Endobiotic species comprised the lithophagous bivalves Lithophaga aristata and Rocellaria dubia of different sizes, communicating with the outside through tiny perforations. Intra-shell tunnels and galleries also sheltered annelids and sipunculids. Epibiotic species comprised algae and highly diversified invertebrates represented by crustaceans, polychaetes, molluscs, echinoderms, ascidians, sponges, bryozoans and sipunculids, with barnacles being the most common group. Comparison of growth features between non-fouled and fouled S. haemastoma revealed higher growth in non-fouled specimens. Differences in reproductive condition indices were detected in few months, being mostly higher in non-fouled snails, but showed no asynchrony in the spawning period for either fouled or non-fouled gastropods hosts.

  7. Fishery status, growth, reproduction biology and feeding habit of two scombrid fish from the Gulf of Aqaba, Red Sea

    International Nuclear Information System (INIS)

    Al-Zibdah, M.; Odat, N.

    2007-01-01

    The fishery and some biological aspects of two Scombrid fish species, Katsuwonus pelamis and Euthynnus affinis from the Gulf of Aqaba were studied during one year period (1999-2000). Monthly samples of the two species were collected to investigate growth, reproduction and feeding habit. Results showed that the Scombridae family form more than 60% of the total catch of Jordanian fishery. The length-weight relationships (LWr) in the two fish species demonstrated thatthe growth is of an allometric type (around 3). The condition factor (k) showed relatively consistent values in both species but revealed slight variability in growth periods. This could be attributed to the limited food availability in fish natural habitat. Different age classes were observed in the catch of the two species irrespective of season. The mean GSI exhibited similar change pattern with season in both sexes of the two fish. Spawning behavior and planktonic larvae of both fish were not observed in the field. This could be inferred that these fish are not migrating to the region for reproduction. The food composition of K. pelamis and E. affinis suggests that the fish compete for the same food items. These are the fish At herinomorous lacunosus, crustacean and molluscans. Prey occurrence in fish stomachs is attributed mainly to the seasonal availability of food in the Gulf of Aqaba. High abundance of food items in winter may indicate that the two species migrate at the climax of primary productivity in the Gulf. (author)

  8. Asymmetric changes of growth and reproductive investment herald altitudinal and latitudinal range shifts of two woody species.

    Science.gov (United States)

    Matías, Luis; Jump, Alistair S

    2015-02-01

    Ongoing changes in global climate are altering ecological conditions for many species. The consequences of such changes are typically most evident at the edge of the geographical distribution of a species, where range expansions or contractions may occur. Current demographical status at geographical range limits can help us to predict population trends and their implications for the future distribution of the species. Thus, understanding the comparability of demographical patterns occurring along both altitudinal and latitudinal gradients would be highly informative. In this study, we analyse the differences in the demography of two woody species through altitudinal gradients at their southernmost distribution limit and the consistency of demographical patterns at the treeline across a latitudinal gradient covering the complete distribution range. We focus on Pinus sylvestris and Juniperus communis, assessing their demographical structure (density, age and mortality rate), growth, reproduction investment and damage from herbivory on 53 populations covering the upper, central and lower altitudes as well as the treeline at central latitude and northernmost and southernmost latitudinal distribution limits. For both species, populations at the lowermost altitude presented older age structure, higher mortality, decreased growth and lower reproduction when compared to the upper limit, indicating higher fitness at the treeline. This trend at the treeline was generally maintained through the latitudinal gradient, but with a decreased growth at the northern edge for both species and lower reproduction for P. sylvestris. However, altitudinal and latitudinal transects are not directly comparable as factors other than climate, including herbivore pressure or human management, must be taken into account if we are to understand how to infer latitudinal processes from altitudinal data. © 2014 John Wiley & Sons Ltd.

  9. Testing the effect of dietary carotenoids on larval survival, growth and development in the critically endangered southern corroboree frog.

    Science.gov (United States)

    Byrne, Phillip G; Silla, Aimee J

    2017-03-01

    The success of captive breeding programs (CBPs) for threatened species is often limited due to a lack of knowledge of the nutritional conditions required for optimal growth and survival. Carotenoids are powerful antioxidants known to accelerate vertebrate growth and reduce mortality. However, the effect of carotenoids on amphibian life-history traits remains poorly understood. The aim of our study was to use a manipulative laboratory experiment to test the effect of dietary-carotenoid supplementation during the larval life stage on the survival, growth and development of the critically endangered southern corroboree frog (Pseudophryne corroboree). Larvae were fed either a carotenoid supplemented diet or an unsupplemented diet and the survival, growth and development of individuals was monitored and compared. There was no significant effect of dietary treatment on larval survival, growth rate, time taken to reach metamorphosis, or body size at metamorphosis. Our findings provide no evidence that carotenoid supplementation during the larval life stage improves the growth and development of southern corroboree frogs. However, because the carotenoid dose used in our study did not have any detrimental effects on P. corroboree larvae, but has previously been shown to improve adult coloration, immunity, and exercise performance, carotenoid supplementation should be considered when evaluating the nutritional requirements of P. corroboree in captivity. Carotenoid supplementation studies are now required for a diversity of anuran species to determine the effects of carotenoids on amphibian survival, growth and development. Understanding the effects of dietary carotenoids on different life-history traits may assist with amphibian captive breeding and conservation. © 2017 Wiley Periodicals, Inc.

  10. Are oysters being bored to death? Influence of Cliona celata on Crassostrea virginica condition, growth and survival.

    Science.gov (United States)

    Carroll, John M; O'Shaughnessy, Kathryn A; Diedrich, Grant A; Finelli, Christopher M

    2015-11-17

    The boring sponge Cliona celata is a nuisance species that can have deleterious effects on eastern oyster Crassostrea virginica growth, condition, and survival. Surprisingly, however, these effects have not been well documented and when examined, results have been equi-vocal. In this study, we provide a direct comparison of growth, condition, and survival of sponge-colonized and uncolonized oysters in southeast North Carolina in 2 separate experiments. In the first experiment, sponge-colonized oysters exhibited significantly slower growth rates, reduced condition, and lower survival relative to uncolonized oysters, although results may have been confounded by oyster source. In the second experiment, using smaller oysters from the same source population, growth rate was again significantly reduced in colonized oysters relative to uncolonized oysters, however neither condition nor survival differed. In field surveys of the same population, colonized individuals across a range of sizes demonstrated significantly reduced condition. Further, condition index was negatively correlated with sponge biomass, which was positively correlated with oyster size, suggesting that the impact of the sponge changes with ontogeny. By investigating clearance rates, tissue isotopic and nutrient content, as well as caloric value, this study provides further evidence that sponge presence causes the oysters to divert energy into costly shell maintenance and repair at the expense of shell and somatic growth. Thus, although variable, our results demonstrate negative impacts of sponge infestation on oyster demographics, particularly as oysters grow larger.

  11. Effect of Ppd-1 on the expression of flowering-time genes in vegetative and reproductive growth stages of wheat.

    Science.gov (United States)

    Kitagawa, Satoshi; Shimada, Sanae; Murai, Koji

    2012-01-01

    The photoperiod sensitivity gene Ppd-1 influences the timing of flowering in temperate cereals such as wheat and barley. The effect of Ppd-1 on the expression of flowering-time genes was assessed by examining the expression levels of the vernalization genes VRN1 and VRN3/WFT and of two CONSTANS-like genes, WCO1 and TaHd1, during vegetative and reproductive growth stages. Two near-isogenic lines (NILs) were used: the first carried a photoperiod-insensitive allele of Ppd-1 (Ppd-1a-NIL), the other, a photoperiod-sensitive allele (Ppd-1b-NIL). We found that the expression pattern of VRN1 was similar in Ppd-1a-NIL and Ppd-1b-NIL plants, suggesting that VRN1 is not regulated by Ppd-1. Under long day conditions, VRN3/WFT showed similar expression patterns in Ppd-1a-NIL and Ppd-1b-NIL plants. However, expression differed greatly under short day conditions: VRN3/WFT expression was detected in Ppd-1a-NIL plants at the 5-leaf stage when they transited from vegetative to reproductive growth; very low expression was present in Ppd-1b-NIL throughout all growth stages. Thus, the Ppd-1b allele acts to down-regulate VRN3/WFT under short day conditions. WCO1 showed high levels of expression at the vegetative stage, which decreased during the phase transition and reproductive growth stages in both Ppd-1a-NIL and Ppd-1b-NIL plants under short day conditions. By contrast to WCO1, TaHd1 was up-regulated during the reproductive stage. The level of TaHd1 expression was much higher in Ppd-1a-NIL than the Ppd-1b-NIL plants, suggesting that the Ppd-1b allele down-regulates TaHd1 under short day conditions. The present study indicates that down-regulation of VRN3/WFT together with TaHd1 is the cause of late flowering in the Ppd-1b-NIL plants under short day conditions.

  12. Against all odds: Tales of survival and growth of the Foundational Approaches in Science Teaching (FAST) project

    Science.gov (United States)

    Yamamoto, Karen Kina

    This study examines the dynamics of survival and growth of curricular and instructional innovations. It focuses on the Foundational Approaches in Science Teaching (FAST) project, a long-term survivor of reform in science education. Key questions guiding this study include: (1) How did the FAST project survive over the past 30 years? (2) What elements are essential for long-term survival and growth of an innovative science program? (3) Why did the project continue to survive amidst several waves of educational reform? The core of my conceptual framework is that the odds of survival and growth of curricular and instructional innovations are increased by the extent to which resources, theory-based curriculum development processes, and professional development strategies are not only incorporated into but also interdependent within a project. With this framework as a guide, the main methods of data collection were document analysis, interviews, and observations. FAST, developed by the University of Hawaii's Curriculum Research and Development Group (CRDG), consists of a sequential and interdisciplinary middle and high school science program for students in grades 6-10. According to the results of this study, the project was able to survive by receiving constant organizational support from CRDG and a steady source of State funding through the university since 1966; it also retained a relatively small but stable staff of highly qualified project personnel. Formulated on a discipline-based theory that values development of students' intellectual capacities as the platform for curriculum research, design, and development, the FAST project translated this vision of science education into key elements of an innovative program that survived and thrived: (1) an interdisciplinary program consisting of physical, biological, and earth sciences; inquiry as content and process; history and philosophy of science; and links between and among sciences, technology, and society; and (2

  13. Effects of submergence on growth and survival of saplings of three wetland trees differing in adaptive mechanisms for flood tolerance

    Directory of Open Access Journals (Sweden)

    Fumiko Iwanaga

    2015-04-01

    Full Text Available Aim of study: Withstanding total submergence and reaeration following submergence is essential for the survival and establishment of wetland species. We focused on “LOES–low oxygen escape syndrome” and “LOQS–low oxygen quiescence syndrome” and compared tolerances to total submergence among wetland woody species differing in morphological adaptation to soil flooding. Area of study, materials and methods: This study examined the survival of 2-year-old saplings of Taxodium distichum and Metasequioia glyptostroboides (LOQS species, and Alnus japonica (LOES species, during and after total submergence. Saplings were completely submerged, then de-submerged to determine trends in survival and growth Main results: The M. glyptostroboides and A. japonica saplings could not survive prolonged submergence for more than 8 weeks, whereas saplings of T. distichum survived for over 2 years. Submerged saplings of all species showed no significant growth or modifications in morphology and anatomy under water, such as shoot elongation, adventitious root formation, and/or aerenchyma development. All T. distichum saplings that were de-submerged in the second year had the same pattern of shoot growth regardless of differences in timing and seasonality of de-submergence. Wood formation in T. distichum saplings ceased during submergence and resumed after de-submergence in spring and summer, but not in autumn. Research highlights: T. distichum saplings, which survived longer submergence periods than A. japonica and M. glyptostroboides, had physiological characteristics, such as suspension of growth and metabolism, which allowed survival of protracted total submergence (at least 2 years when saplings were immersed during the dormant stage before leaf flushing.

  14. Growth and survival of Hippocampus erectus (Perry, 1810 juveniles fed on Artemia with different HUFA levels

    Directory of Open Access Journals (Sweden)

    Nicolás Vite-Garcia

    2014-03-01

    Full Text Available Survival during first months after birth is one of the bottlenecks for consolidating the seahorse farming industry. In this work, Artemia metanauplii enriched with two highly unsaturated fatty acids (HUFA rich commercial emulsions with different docosahexaenoic acid (DHA levels (63% and 14% of total lipids, a vegetable oil with no DHA, and non-enriched Artemia as control, were used to feed 5-day-old juvenile Hippocampus erectus for 60 days. Enriched Artemia had similar levels of DHA (13% and 9%, despite great differences of DHA in the emulsions, with traces of DHA in non-enriched and vegetable oil enriched Artemia. More than 20% of DHA was found in 24 h starved juveniles fed both DHA-enriched treatments, similar to values in newly born juveniles, but those fed vegetable oil enriched Artemia or non-enriched Artemia had 5% of DHA. Total lipid and protein levels were similar in juveniles from the four treatments. The n-3/n-6 ratio was almost four-fold higher in seahorses fed DHA-enriched treatments compared to juveniles fed the non-enriched treatments. Survival of seahorses only partially reflected the DHA levels: it was lower in the vegetable oil treatment, similar in the seahorses fed Artemia with higher DHA and in the control treatment, and higher in seahorses fed the HUFA-enriched Artemia with lower DHA levels, although growth was similar in the two DHA-enriched Artemia treatments. Juvenile H. erectus seahorses perform better when they have at least 20% of DHA in their tissues, and these levels can be attained with no more than 14% of DHA in emulsions, eliminating the need for more expensive emulsions with higher DHA levels.

  15. Influence of an extreme high water event on survival, reproduction, and distribution of snail kites in Florida, USA

    Science.gov (United States)

    Bennetts, R.E.; Kitchens, W.M.; Dreitz, V.J.

    2002-01-01

    Hydrology frequently has been reported as the environmental variable having the greatest influence on Florida snail kite (Rostrhamus sociabilis) populations. Although drought has received the most attention, high-water conditions also have been reported to affect kites. Years of high water generally have been reported to be favorable for nesting, although prolonged high water may be detrimental to sustaining suitable habitat. During 1994 and 1995, southern Florida experienced an extreme high water event. This event enabled us to compare survival, nesting success, number of young per successful nest, and spatial distribution of nesting before, during, and after the event. We found no evidence of an effect (either negative or positive) on survival of adult kites. In contrast, juvenile kites experienced the highest survival during the event, although our data suggest greater annual variability than can be explained by the event alone. We found no evidence of an effect of the high water event on nest success or number of young per successful nest. Nest success was highest during the event in the southern portion of the range but was quite similar to other years, both before and after the event. Our data do indicate a substantial shift in the spatial distribution of nesting birds. During the event, nesting activity shifted to higher elevations (i.e., shallower water) in the major nesting areas of the Everglades region. Nesting also occurred in Big Cypress National Preserve during the event, which is typically too dry to support nesting kites. Thus, our data indicate a potential short-term benefit of increased juvenile survival and an expansion of nesting habitat. However, the deterioration of habitat quality from prolonged high water precludes any recommendation for such conditions to be maintained for extended periods. ?? 2002, The Society of Wetland Scientists.

  16. Effect of Different Medium on Survival Rate and Growth of Chironomus sp. Larvae

    Directory of Open Access Journals (Sweden)

    . Widanarni

    2007-07-01

    Full Text Available In the ornamental fish and fish for food culture, feeding by natural feed is very suitable since they are easy to digest and their size is suitable with  to larval mouth.  One of natural foods is blood worm Chironomus sp. larvae that has high protein content (till  65.2% of  protein. Until now, blood worm is obtained from nature and their stock depends on the weather.  That problem  may be overcome by culturing blood worm in appropriate culture medium.  Naturally, Chironomus sp. grows well in the water containing sago waste.  This study was carried out to examine the growth of Chironomus sp. reared in the medium containing mud, solid sago waste, solid tapioca wastes and water with no waste in depth of 0.5 cm. After 35-day rearing, survival rate of Chironomus sp was different among the treatments, while growth in length was similar. The best survival rate, 58.93% was obtained in the media containing solid sago waste.   Keywords: Chironomus, blood worm, sago waste, tapioca waste   ABSTRAK Dalam usaha budidaya ikan hias maupun ikan konsumsi, pemberian pakan alami sangat cocok karena mudah dicerna dan sesuai dengan bukaan mulut larva. Salah satu contoh pakan alami adalah Chironomus sp. (blood worm yang mempunyai kandungan protein mencapai 65,2%. Selama ini cacing darah diperoleh dari alam dan suplainya tergantung pada kondisi musim. Hal ini mungkin dapat diatasi dengan membudidayakan cacing darah dengan  media yang sesuai sebagai tempat hidupnya. Secara alami, Chironomus sp. dapat tumbuh dan berkembang dengan baik pada limbah sagu. Penelitian ini dilakukan untuk mengetahui pertumbuhan Chironomus sp. yang dipelihara pada media berupa lumpur, limbah sagu padat, limbah tapioka padat dan air tanpa limbah dengan ketebalan media 0,5 cm. Setelah 35 hari masa pemeliharaan, diketahui bahwa penggunaan media limbah padat sagu, limbah padat tapioka, lumpur dan air tanpa limbah pada pemeliharaan Chironomus sp. masing-masing menghasilkan tingkat

  17. Zostera marina (eelgrass) growth and survival along a gradient ofnutrients and turbidity in the lower Chesapeake Bay

    Science.gov (United States)

    Moore, K.A.; Neckles, H.A.; Orth, R.J.

    1996-01-01

    Survival of transplanted Zostera marina L. (eelgrass), Z. marina growth,and environmental conditions were studied concurrently at a number of sitesin a southwestern tributary of the Chesapeake Bay to elucidate the factorslimiting macrophyte distribution in this region. Consistent differences insurvival of the transplants were observed, with no long-term survival at anyof the sites that were formerly vegetated with this species but thatcurrently remain unvegetated. Therefore, the current distribution of Z.marina likely represents the extent of suitable environmental conditions inthe region, and the lack of recovery into historically vegetated sites is notsolely due to lack of propagules. Poor long-term survival was related toseasonally high levels of water column light attenuation. Fall transplantsdied by the end of summer following exposure to levels of high springturbidity (K(d) > 3.0). Accumulation of an epiphyte matrix during the latespring (0.36 to 1.14 g g-1 dry wt) may also have contributed to thisstress. Differences in water column nutrient levels among sites during thefall and winter (10 to 15 ??M dissolved inorganic nitrogen and 1 ??Mdissolved inorganic phosphates) had no observable effect on epiphyteaccumulation or macrophyte growth. Salinity effects were minor and there wereno symptoms of disease. Although summertime conditions resulted indepressions in growth, they did not alone limit long-term survival. It issuggested that water quality conditions enhancing adequate seagrass growthduring the spring may be key to long-term Z. marina survival and successfulrecolonization in this region.

  18. A Comparison of Growth and Survival of Aquacultured Juvenile Florida Pompano fed Fishmeal and Plant-Based Diets

    Science.gov (United States)

    Budden, D.

    2016-02-01

    We investigated the growth and survival of aquacultured juvenile Florida Pompano (Trachinotus carolinus) fed two different diets. Pompano (initial weight 7.7 g /fish) were randomly assigned to one of two dietary treatments: Zeigler pellets (fishmeal; 35% protein, 5% lipid) and a plant-based Repashy Soilent Green algae gel (plant-based; 35% protein, 6% lipid). Fish were fed rations of 5% body weight twice daily for eight weeks. Despite nearly equivalent proximate compositions for the two feeds, survival rates were significantly affected by diet. All fish fed the Zeigler diet survived; however, mortality was observed in 92% of the fish fed the Repashy diet. At the end of the trial, mean weight gain of surviving pompano was highest in fish fed Zeigler pellets. Mean specific growth rate (SGR) for fish fed the Zeigler diet (0.24% per day) was higher than for fish fed Repashy (-2.44%).While plant-based feeds have been successfully used with the species, these results suggest that the plant-based Repashy diet is not suitable for survival or growth of aquacultured Florida pompano.

  19. Plastic growth of the herbivorous reef fish Sparisoma viride: field evidence for a trade-off between growth and reproduction

    NARCIS (Netherlands)

    van Rooij, J.M.; Bruggemann, J.H.; Videler, J.J.; Breeman, A.M.

    The growth of different Life phases and social categories of the protogynous parrotfish Sparisoma viride was studied on a fringing reef on Bonaire (Netherlands Antilles) using mark-recapture procedures and by taking repeated stereographic measurements of free-swimming fish. Weight-growth was best

  20. Early development, survival and growth rates of the giant clam Tridacna crocea (Bivalvia: Tridacnidae

    Directory of Open Access Journals (Sweden)

    Miguel Mies

    2012-06-01

    Full Text Available Tridacnid clams are conspicuous inhabitants of Indo-Pacific coral reefs and are traded and cultivated for the aquarium and food industries. In the present study, daily growth rates of larvae of the giant clam Tridacna crocea were determined in the laboratory during the first week of life. Adults were induced to spawn via intra-gonadal serotonin injection through the byssal orifice. After spawning oocytes were collected, fertilized and kept in 3 L glass beakers and raceways treated with antibiotics to avoid culture contamination. Larvae were fed twice with the microalga Isochrysis galbana and zooxanthellae were also offered twice during the veliger stage (days 4 and 6. Larval length was measured using a digitizing tablet coupled to a microcomputer. Larval mortality was exponential during the first 48 hours of life declining significantly afterwards. Mean growth rate was 11.3 μm day-1, increasing after addition of symbionts to 18.0 μm day-1. Survival increased to ca. 75% after the addition of zooxanthellae. The results describe the growth curve for T. crocea larvae and suggest that the acquisition of symbionts by larvae may be useful for larval growth and survival even before larvae have attained metamorphosis.Bivalves tridacnídeos são habitantes conspícuos dos recifes da região do Indo-Pacífico e são cultivados e comercializados para os mercados alimentício e aquarista. No estudo apresentado foram determinadas as taxas de crescimento diário durante a primeira semana de vida da larva do bivalve ornamental Tridacna crocea. As matrizes foram induzidas à desova por meio de uma injeção intragonadal de serotonina realizada através do orifício bissal. Após desova, ovócitos foram coletados, fertilizados e mantidos em béqueres de vidro e tanques de fluxo contínuo tratados com antibióticos para evitar contaminação. Larvas foram alimentadas em duas ocasiões com a microalga Isochrysis galbana e zooxantelas foram oferecidas também por

  1. Edema control by cediranib, a vascular endothelial growth factor receptor-targeted kinase inhibitor, prolongs survival despite persistent brain tumor growth in mice

    DEFF Research Database (Denmark)

    Kamoun, Walid S; Ley, Carsten D; Farrar, Christian T

    2009-01-01

    anti-VEGF agents may decrease tumor contrast-enhancement, vascularity, and edema, the mechanisms leading to improved survival in patients remain incompletely understood. Our goal was to determine whether alleviation of edema by anti-VEGF agents alone could increase survival in mice. METHODS: We treated...... mice bearing three different orthotopic models of glioblastoma with a VEGF-targeted kinase inhibitor, cediranib. Using intravital microscopy, molecular techniques, and magnetic resonance imaging (MRI), we measured survival, tumor growth, edema, vascular morphology and function, cancer cell apoptosis...... by an increase in plasma collagen IV. These rapid changes in tumor vascular morphology and function led to edema alleviation -- as measured by MRI and by dry/wet weight measurement of water content -- but did not affect tumor growth. By immunohistochemistry, we found a transient decrease in macrophage...

  2. Vulnerability to cavitation, hydraulic efficiency, growth and survival in an insular pine (Pinus canariensis).

    Science.gov (United States)

    López, Rosana; López de Heredia, Unai; Collada, Carmen; Cano, Francisco Javier; Emerson, Brent C; Cochard, Hervé; Gil, Luis

    2013-06-01

    It is widely accepted that hydraulic failure due to xylem embolism is a key factor contributing to drought-induced mortality in trees. In the present study, an attempt is made to disentangle phenotypic plasticity from genetic variation in hydraulic traits across the entire distribution area of a tree species to detect adaptation to local environments. A series of traits related to hydraulics (vulnerability to cavitation and hydraulic conductivity in branches), growth performance and leaf mass per area were assessed in eight Pinus canariensis populations growing in two common gardens under contrasting environments. In addition, the neutral genetic variability (FST) and the genetic differentiation of phenotypic variation (QST) were compared in order to identify the evolutionary forces acting on these traits. The variability for hydraulic traits was largely due to phenotypic plasticity. Nevertheless, the vulnerability to cavitation displayed a significant genetic variability (approx. 5 % of the explained variation), and a significant genetic × environment interaction (between 5 and 19 % of the explained variation). The strong correlation between vulnerability to cavitation and survival in the xeric common garden (r = -0·81; P < 0·05) suggests a role for the former in the adaptation to xeric environments. Populations from drier sites and higher temperature seasonality were less vulnerable to cavitation than those growing at mesic sites. No trade-off between xylem safety and efficiency was detected. QST of parameters of the vulnerability curve (0·365 for P50 and the slope of the vulnerability curve and 0·452 for P88) differed substantially from FST (0·091), indicating divergent selection. In contrast, genetic drift alone was found to be sufficient to explain patterns of differentiation for xylem efficiency and growth. The ability of P. canariensis to inhabit a wide range of ecosystems seemed to be associated with high phenotypic plasticity and some degree of local

  3. The effects of epoxiconazole and α-cypermethrin on Daphnia magna growth, reproduction, and offspring size

    DEFF Research Database (Denmark)

    Gottardi, Michele; Birch, Michala Rosa; Dalhoff, Kristoffer

    2017-01-01

    of sublethal concentrations of epoxiconazole and α-cypermethrin and their mixture on growth, reproduction, and in vivo cytochrome P450 activity of the aquatic crustacean Daphnia magna over 42 d. Continuous exposure to nonlethal concentrations of α-cypermethrin at 20 ng/L negatively affected adult growth...... and number and size of neonates within the first 14 d of exposure. Exposure to epoxiconazole at 25 μg/L increased protein content of adults within 1 to 3 d after initiating exposure and increased cumulative number of offspring at exposure times >31 d. Epoxiconazole enhanced the negative effect of α...... with other stressors such as food scarcity, predation, and pathogens, posing an additional hazard for the organisms at the beginning of their life cycle. Environ Toxicol Chem 2017;9999:1-12. © 2017 SETAC....

  4. Survival and growth of restored Piedmont riparian forests as affected by site preparation, planting stock, and planting aids

    Science.gov (United States)

    Chelsea M. Curtis; W. Michael Aust; John R. Seiler; Brian D. Strahm

    2015-01-01

    Forest mitigation sites may have poor survival and growth of planted trees due to poor drainage, compacted soils, and lack of microtopography. The effects of five replications of five forestry mechanical site preparation techniques (Flat, Rip, Bed, Pit, and Mound), four regeneration sources (Direct seed, Bare root, Tubelings, and Gallon), and three planting aids (None...

  5. Effect of directed-spray glyphosate applications on survival and growth of planted oaks after three growing seasons

    Science.gov (United States)

    Andrew B. Self; Andrew W. Ezell; Josh L. Moree; Rory O. Thornton

    2013-01-01

    Thousands of acres of oak (Quercus spp.) plantations are established across the South annually. Survival and growth of these plantings have been less than desirable. Several techniques have been utilized in attempts to achieve improved success in these areas. One such technique that has been recommended is the application of directed-spray herbicide...

  6. Single-tree harvesting reduces survival and growth of oak stump sprouts in the Missouri Ozark Highlands

    Science.gov (United States)

    Daniel C. Dey; Randy G. Jensen; Michael J. Wallendorf

    2008-01-01

    Regeneration and recruitment into the overstory is critical to the success of using uneven-aged systems to sustain oak forests. We evaluated survival and growth of white oak (Quercus alba L.), black oak (Q. velutina Lam.), and scarlet oak (Q. coccinea Muenchh.) stump sprouts 10 years after harvesting Ozark...

  7. Chemical and physical effects of crowding on growth and survival of Penaeus monodon Fabricius post-larvae

    NARCIS (Netherlands)

    Nga, B.T.; Lürling, M.F.L.L.W.; Peeters, E.T.H.M.; Roijackers, R.M.M.; Scheffer, M.; Nghia, T.T.

    2005-01-01

    The hypothesis that crowding effects through physical and/or chemical interference may be an important factor in lowering the chance of survival and reducing growth of Penaeus monodon post-larvae under high stocking densities was tested. To separate physical interference from chemically-exerted

  8. Habitat-specific biomass, survival and growth of rainbow trout (Oncorhynchus mykiss) during summer in a small coastal stream

    Science.gov (United States)

    Bret C. Harvey; Jason L. White; Rodney J. Nakamoto

    2005-01-01

    We observed significant habitat-scale variation in the density, survival, and growth of 811 passive integrated transponder tagged rainbow trout (Oncorhynchus mykiss) enclosed for 63—68 days at natural density in 59 individual habitats (pools and riffles) in a small coastal California stream in summer 2001. The initial habitat-scale...

  9. The effect of deposited fine sediment on summer survival and growth of rainbow trout in riffles of a small stream

    Science.gov (United States)

    Bret C. Harvey; Jason L. White; Rodney J. Nakamoto

    2009-01-01

    Elevated fine-sediment inputs to streams can alter a variety of conditions and processes, including the amount of fine sediment stored in riffles. We sought to measure the influence of deposited fine sediment on the survival and growth of juvenile rainbow trout Oncorhynchus mykiss (106–130 mm fork length) using a field experiment that included 18 enclosures in riffles...

  10. Big-leaf mahogany (Swietenia macrophylla) seedling survival and growth across a topographic gradient in southeast Pará, Brazil

    Science.gov (United States)

    James Grogana; Mark S. Ashtona; Galv& atilde; Jurandir oc

    2003-01-01

    Adult populations of big-leaf mahogany (Swietenia macrophylla) occur in aggregations along seasonal streams in transitional evergreen forests of southeast Pará, Brazil. To test whether variable seedling survival and growth across topography may underlie this observed distribution pattern, we planted nursery-grown seedlings in the...

  11. Effects of disking, bedding, and subsoiling on survival and growth of three oak species in central Mississippi

    Science.gov (United States)

    J. Paul Jeffreys; Emily B. Schultz; Thomas G. Matney; W. Cade Booth; Jason M. Morris

    2010-01-01

    A replicated split-plot design experiment to evaluate the effects of three site preparation methods (disking, bedding, and subsoiling plus bedding) on survival and growth of three oak species (cherrybark, Quercus pagoda Raf.; Shumard, Quercus shumardii Buckl.; and Nuttall, Quercus texana Buckl.) was established...

  12. Divergence for residual feed intake of Holstein-Friesian cattle during growth did not affect production and reproduction during lactation.

    Science.gov (United States)

    Macdonald, K A; Thomson, B P; Waghorn, G C

    2016-11-01

    Residual feed intake (RFI) is the difference between actual and predicted dry matter intake (DMI) of individual animals. Recent studies with Holstein-Friesian calves have identified an ~20% difference in RFI during growth (calf RFI) and these groups remained divergent in RFI during lactation. The objective of the experiment described here was to determine if cows selected for divergent RFI as calves differed in milk production, reproduction or in the profiles of BW and body condition score (BCS) change during lactation, when grazing pasture. The cows used in the experiment (n=126) had an RFI of -0.88 and +0.75 kg DM intake/day for growth as calves (efficient and inefficient calf RFI groups, respectively) and were intensively grazed at four stocking rates (SR) of 2.2, 2.6, 3.1 and 3.6 cows/ha on self-contained farmlets, over 3 years. Each SR treatment had equal number of cows identified as low and high calf RFI, with 24, 28, 34 and 40/11 ha farmlet. The cows divergent for calf RFI were randomly allocated to each SR. Although SR affected production, calf RFI group (low or high) did not affect milk production, reproduction, BW, BCS or changes in these parameters throughout lactation. The most efficient animals (low calf RFI) lost similar BW and BCS as the least efficient (high calf RFI) immediately post-calving, and regained similar BW and BCS before their next calving. These results indicate that selection for RFI as calves to increase efficiency of feed utilisation did not negatively affect farm productivity variables (milk production, BCS, BW and reproduction) as adults when managed under an intensive pastoral grazing system.

  13. The importance of microclimate variation in determining size, growth and survival of avian offspring: experimental evidence from a cavity nesting passerine.

    Science.gov (United States)

    Dawson, Russell D; Lawrie, Cheyenne C; O'Brien, Erin L

    2005-07-01

    Organisms are expected to balance energy allocation in such a way that fitness is maximized. While much research has focussed on allocation strategies of reproducing parents, in particular birds, relatively little attention has been paid to how nestlings allocate energy while in the nest. Nestling birds are faced with a trade-off between devoting energy to growth or to thermoregulation, and in altricial species it is likely that the thermal environment of the nest site influences the nature of this trade-off. Here, we experimentally investigate how altering the microclimate of nests affects the growth, size and survival, as well as cell-mediated immune (CMI) response, of nestling tree swallows (Tachycineta bicolor) in a temperate environment. We place air-activated heating pads in nests of swallows when young were between 4 days and 16 days of age, and compared performance of offspring to control nests. Our manipulation raised temperatures of heated nests by approximately 5 degrees C compared to control nests. Offspring in heated nests had enhanced survival while in the nest, and we also found that they were heavier and had longer ninth primary feathers at 16 days of age. In addition, heating nest boxes resulted in significantly faster growth of primaries, and there was a trend for growth rates of mass to also be higher in heated nests. There were no significant differences between heated and control nests in growth rate or size of tarsus at age 16 days, and we speculate that this lack of response to elevated nest temperatures may be due to growth of skeletal structures being limited by other factors such as calcium availability. We also found no difference between heated and control nests in CMI response. Nonetheless, our results show overall that increasing temperatures of nests has significant benefits that enhance the fitness of offspring. As provisioning rates to offspring did not differ between heated and control nests, we suspect that the beneficial effects

  14. Effects of hydrogen fluoride fumigation of bean plants on the growth, development, and reproduction of the Mexican bean beetle

    Energy Technology Data Exchange (ETDEWEB)

    Weinstein, L H; McCune, D C; Mancini, J F; van Leuken, P

    1973-01-01

    The growth and behavior of Mexican bean beetle populations on control and hydrogen fluoride-fumigated bean plants (P. vulgaris L.) were investigated to assess the effects of such fumigation on beetle growth, development and reproduction. Beetles that were cultured on HF-fumigated plants were generally lighter than controls, although the occurrence and magnitude of this effect depended upon stage of development, age, and sex of the adult beetle and the number of generations of culture on HF-fumigated plants. A consistently decreased mass of larvae cultured on HF-fumigated tissue pupated and enclosed three to six days later than controls, and the adults commenced reproductive activity with the same lag in time. Beetles cultured on the fumigated plants also contained greater amounts of fluoride than the controls, and the fluoride content of females was greater than that of males on both HF-fumigated and control plants. Beetles raised on fumigated plants laid fewer egg masses and fewer eggs per mass, although when the first generation was repeated at a later date there was no significant effect. Feeding activity was reduced in both larval and adult stages in beetles cultured on the fumigated plants, and adults showed less flight activity than controls. A difference in color of the elytra was also noted; beetles on HF-fumigated plants were paler than controls.

  15. Survival and reproductive capacity of the tobacco budworm, heliothis virescens (lepidoptera:noctuidae), irradiated as diapausing and young nondiapausing pupae

    International Nuclear Information System (INIS)

    Proshold, F.I.; North, D.T.

    1978-01-01

    Pupal survival, mating, and sperm transfer in tobacco budworm, Heliothis virescens (F.), irradiated as diapause pupae, decreased proportionately with increasing doses of 3, 5, and 7.5 krad. Also, the fertility of tobacco budworms irradiated as nondiapause pupae and of the F 1 progeny of such males decreased with increasing dose. When the female partner received eupyrene sperm, insects irradiated while the pupae were in diapause were fertile as were their progeny. Therefore, it does not appear plausible to irradiate diapause pupae of our strain of tobacco budworms to obtain sterile insects for a release program. (author)

  16. Growth, chamber building rate and reproduction time of Palaeonummulites venosus (Foraminifera) under natural conditions

    Science.gov (United States)

    Kinoshita, Shunichi; Eder, Wolfgang; Wöger, Julia; Hohenegger, Johann; Briguglio, Antonino

    2017-12-01

    We investigated the symbiont-bearing benthic foraminifer Palaeonummulites venosus to determine the chamber building rate (CBR), test diameter increase rate (DIR), reproduction time and longevity using the `natural laboratory' approach. This is based on the decomposition of monthly obtained frequency distributions of chamber number and test diameter into normally distributed components. Test measurements were taken using MicroCT. The shift of the mean and standard deviation of component parameters during the 15-month investigation period was used to calculate Michaelis-Menten functions applied to estimate the averaged CBR and DIR under natural conditions. The individual dates of birth were estimated using the inverse averaged CBR and the inverse DIR fitted by the individual chamber number or the individual test diameter at the sampling date. Distributions of frequencies and densities (i.e., frequency divided by sediment weight) based on both CBR and DIR revealed continuous reproduction throughout the year with two peaks, a stronger one in June determined as the onset of the summer generation (generation 1) and a weaker one in November determined as the onset of the winter generation (generation 2). This reproduction scheme explains the presence of small and large specimens in the same sample. Longevity, calculated as the maximum difference in days between the individual's birth date and the sampling date, is approximately 1.5 yr, an estimation obtained by using both CBR and DIR.

  17. Growth, chamber building rate and reproduction time of Palaeonummulites venosus under natural conditions.

    Science.gov (United States)

    Kinoshita, Shunichi; Eder, Wolfgang; Wöger, Julia; Hohenegger, Johann; Briguglio, Antonino

    2017-04-01

    Investigations on Palaeonummulites venosus using the natural laboratory approach for determining chamber building rate, test diameter increase rate, reproduction time and longevity is based on the decomposition of monthly obtained frequency distributions based on chamber number and test diameter into normal-distributed components. The shift of the component parameters 'mean' and 'standard deviation' during the investigation period of 15 months was used to calculate Michaelis-Menten functions applied to estimate the averaged chamber building rate and diameter increase rate under natural conditions. The individual dates of birth were estimated using the inverse averaged chamber building rate and the inverse diameter increase rate fitted by the individual chamber number or the individual test diameter at the sampling date. Distributions of frequencies and densities (i.e. frequency divided by sediment weight) based on chamber building rate and diameter increase rate resulted both in a continuous reproduction through the year with two peaks, the stronger in May /June determined as the beginning of the summer generation (generation1) and the weaker in November determined as the beginning of the winter generation (generation 2). This reproduction scheme explains the existence of small and large specimens in the same sample. Longevity, calculated as the maximum difference in days between the individual's birth date and the sampling date seems to be round about one year, obtained by both estimations based on the chamber building rate and the diameter increase rate.

  18. Survival and growth rates of juvenile salmonids reared in lowland streams

    Directory of Open Access Journals (Sweden)

    Golski Janusz

    2016-12-01

    Full Text Available The aim of this study was to assess the efficiency of propagating juvenile trout, Salmo trutta L. in small lowland streams and to evaluate the impact of the environmental conditions in the streams on the juvenile fish. Brown trout (Salmo trutta fario and sea trout (Salmo trutta trutta early fry fed under controlled conditions were used to stock third-order lowland streams. During summer, fall, and spring catches, fry were counted, measured, and weighed. The following parameters were calculated using the data collected: fry stocking density (ind. m-2; survival; specific mortality rate (SMR; length range; mean specimen length; body weight; mean body weight; specific growth rate (SGR; body condition (Fulton’s index. The ichthyological studies were accompanied by simultaneous analyses of environmental conditions that were performed monthly, and benthic macroinvertebrates were sampled in spring and fall. No differences were observed in the biological parameters analyzed between sea trout and brown trout. Variability in environmental parameters such as temperature, oxygenation, conductivity, and stream width and depth were associated with differentiation in the biological parameters of the fry. The results clearly indicate that the considerable potential of small lowland streams for the propagation of salmonid juvenile stages is currently underexploited.

  19. Mercury critical concentrations to Enchytraeus crypticus (Annelida: Oligochaeta) under normal and extreme conditions of moisture in tropical soils - Reproduction and survival.

    Science.gov (United States)

    Buch, Andressa Cristhy; Schmelz, Rüdiger M; Niva, Cintia Carla; Correia, Maria Elizabeth Fernandes; Silva-Filho, Emmanoel Vieira

    2017-05-01

    Soil provides many ecosystem services that are essential to maintain its quality and healthy development of the flora, fauna and human well-being. Environmental mercury levels may harm the survival and diversity of the soil fauna. In this respect, efforts have been made to establish limit values of mercury (Hg) in soils to terrestrial fauna. Soil organisms such as earthworms and enchytraeids have intimate contact with trace metals in soil by their oral and dermal routes, reflecting the potentially adverse effects of this contaminant. The main goal of this study was to obtain Hg critical concentrations under normal and extreme conditions of moisture in tropical soils to Enchytraeus crypticus to order to assess if climate change may potentiate their acute and chronic toxicity effects. Tropical soils were sampled from of two Forest Conservation Units of the Rio de Janeiro State - Brazil, which has been contaminated by Hg atmospheric depositions. Worms were exposed to three moisture conditions, at 20%, 50% and 80% of water holding capacity, respectively, and in combination with different Hg (HgCl 2 ) concentrations spiked in three types of tropical soil (two natural soils and one artificial soil). The tested concentrations ranged from 0 to 512mg Hg kg -1 dry weight. Results indicate that the Hg toxicity is higher under increased conditions of moisture, significantly affecting survival and reproduction rate. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Reproductive survival of explanted human tumor cells after exposure to nitrogen mustard or x irradiation; differences in response with subsequent subculture in vitro

    International Nuclear Information System (INIS)

    Wells, J.; Berry, R.J.; Laing, A.H.

    1977-01-01

    Curves for the survival of reproductive capacity of explanted human tumor cells, following exposure to the alkylating agent nitrogen mustard (mustine hydrochloride) or 250-kVp x rays, were obtained as soon as a satisfactory plating efficiency, i.e., greater than or approximately equal to 10 percent, was obtained from the tumor cells in vitro (usually within 2-10 weeks of explanation). It was found that all six tumor explants tested became more sensitive to the action of nitrogen mustard on serial subculture, whereas the response of four explants which were X-irradiated was invariant with further subculturing. Furthermore, all but one explant yielded survival curves which were extremely similar, with D/sub q/ values circa 440-610 rad. One line, from a seminoma, however, had a D/sub q/ of 150 rad. These radiosensitive seminoma cells were, however, the most resistant to the action of nitrogen mustard. The increase in sensitivity to nitrogen mustard with serial subculture in vitro was not associated with any change in the proliferative rate of the cells, although it may be associated with an increase in the efficiency of transport

  1. Fecundity, growth, and survival of the angelfish Pterophyllum scalare (Perciformes: Cichlidae under laboratory conditions

    Directory of Open Access Journals (Sweden)

    Armando A Ortega-Salas

    2009-09-01

    Full Text Available The freshwater angelfishes (Pterophyllum are South American cichlids that have become very popular among aquarists, yet scarce information on their culture and aquarium husbandry exists. We studied Pterophyllum scalare to analyze dietary effects on fecundity, growth, and survival of eggs and larvae during 135 days. Three diets were used: A decapsulated cysts of Artemia, B commercial dry fish food, and C a mix diet of the rotifer Brachionus plicatilis and the cladoceran Daphnia magna. The initial larval density was 100 organisms in each 40L aquarium. With diet A, larvae reached a maximum weight of 3.80g, a total length of 6.3 cm, and a height of 5.8cm; with diet B: 2.80g, 4.81cm, and 4.79cm, and with diet C: 3.00g, 5.15cm, and 5.10cm, respectively. Significant differences were observed between diet A, and diet B and C, but no significantly differences were observed between diets B and C. Fecundity varied from 234 to 1 082 eggs in 20 and 50g females, respectively. Egg survival ranged from 87.4% up to 100%, and larvae survival (80 larvae/40L aquarium from 50% to 66.3% using diet B and A, respectively. Live food was better for growing fish than the commercial balanced food diet. Fecundity and survival are important factors in planning a good production of angelfish. Rev. Biol. Trop. 57 (3: 741-747. Epub 2009 September 30.Se realizaron estudios de cultivo en laboratorio del pez ángel, Pterophyllum scalare, para analizar los efectos de su dieta en la fecundidad, crecimiento y sobrevivencia en huevos y larvas por un período 135 días. Tres dietas diferentes se utilizaron A quistes decapsulados de Artemia, B comida comercial seca para pez, C una mezcla de rotíferos, Brachionus plicatilis y el cladocero, Daphnia magna. La densidad inicial de larvas en acuarios de 40L fue de 100 organismos. Utilizando la dieta A, las larvas alcanzaron un peso máximo de 3.80g, una longitud total de 6.3cm y una altura de 5.8cm; utilizando la dieta B, fue de 2.80g, 4

  2. Impact of small variations in temperature and humidity on the reproductive activity and survival of Aedes aegypti (Diptera, Culicidae)

    International Nuclear Information System (INIS)

    Costa, Ethiene Arruda Pedrosa de Almeida; Santos, Eloina Maria de Mendonca; Correia, Juliana Cavalcanti; Albuquerque, Cleide Maria Ribeiro de

    2010-01-01

    In short space of time increase in temperature and rainfall can affect vector populations and, consequently, the diseases for them transmitted. The present study analyzed the effect of small temperature and humidity variations on the fecundity, fertility and survival of Aedes aegypti. These parameters were analyzed using individual females at temperatures ranging from 23 to 27 deg C (mean 25 deg C); 28 to 32 deg C (mean 30 deg C) and 33 to 37 deg C (mean 35 deg C) associated to 60 +- 8% and 80 +- 6% relative humidity. Females responded to an increase in temperature by reducing egg production, oviposition time and changing oviposition patterns. At 25 deg C and 80% relative humidity, females survived two-fold more and produced 40% more eggs when compared to those kept at 35 deg C and 80% relative humidity. However, in 45% of females kept at 35 deg C and 60% relative humidity oviposition was inhibited and only 15% females laid more than 100 eggs, suggesting that the intensity of the temperature effect was influenced by humidity. Gradual reductions in egg fertility at 60% relative humidity were observed with the increase in temperature, although such effect was not found in the 80% relative humidity at 25 deg C and 30 deg C. These results suggest that the reduction in population densities recorded in tropical areas during seasons when temperatures reach over 35 deg C is likely to be strongly influenced by temperature and humidity, with a negative effect on several aspects of mosquito biology. (author)

  3. Is bigger better? The relationship between size and reproduction in female Asian elephants.

    Science.gov (United States)

    Crawley, J A H; Mumby, H S; Chapman, S N; Lahdenperä, M; Mar, K U; Htut, W; Thura Soe, A; Aung, H H; Lummaa, V

    2017-10-01

    The limited availability of resources is predicted to impose trade-offs between growth, reproduction and self-maintenance in animals. However, although some studies have shown that early reproduction suppresses growth, reproduction positively correlates with size in others. We use detailed records from a large population of semi-captive elephants in Myanmar to assess the relationships between size (height and weight), reproduction and survival in female Asian elephants, a species characterized by slow, costly life history. Although female height gain during the growth period overlapped little with reproductive onset in the population, there was large variation in age at first reproduction and only 81% of final weight had been reached by peak age of reproduction at the population level (19 years). Those females beginning reproduction early tended to be taller and lighter later in life, although these trends were not significant. We found that taller females were more likely to have reproduced by a given age, but such effects diminished with age, suggesting there may be a size threshold to reproduction which is especially important in young females. Because size was not linked with female survival during reproductive ages, the diminishing effect of height on reproduction with age is unlikely to be due to biased survival of larger females. We conclude that although reproduction may not always impose significant costs on growth, height may be a limiting factor to reproduction in young female Asian elephants, which could have important implications considering their birth rates are low and peak reproduction is young - 19 years in this population. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  4. Nicotinamidase modulation of NAD+ biosynthesis and nicotinamide levels separately affect reproductive development and cell survival in C. elegans.

    Science.gov (United States)

    Vrablik, Tracy L; Huang, Li; Lange, Stephanie E; Hanna-Rose, Wendy

    2009-11-01

    Nicotinamide adenine dinucleotide (NAD(+)) is a central molecule in cellular metabolism and an obligate co-substrate for NAD(+)-consuming enzymes, which regulate key biological processes such as longevity and stress responses. Although NAD(+) biosynthesis has been intensely studied, little analysis has been done in developmental models. We have uncovered novel developmental roles for a nicotinamidase (PNC), the first enzyme in the NAD(+) salvage pathway of invertebrates. Mutations in the Caenorhabditis elegans nicotinamidase PNC-1 cause developmental and functional defects in the reproductive system; the development of the gonad is delayed, four uterine cells die by necrosis and the mutant animals are egg-laying defective. The temporal delay in gonad development results from depletion of the salvage pathway product NAD(+), whereas the uv1 cell necrosis and egg-laying defects result from accumulation of the substrate nicotinamide. Thus, regulation of both substrate and product level is key to the biological activity of PNC-1. We also find that diet probably affects the levels of these metabolites, as it affects phenotypes. Finally, we identified a secreted isoform of PNC-1 and confirmed its extracellular localization and functional activity in vivo. We demonstrate that nicotinamide phosphoribosyltransferase (Nampt), the equivalent enzyme in nicotinamide recycling to NAD(+) in vertebrates, can functionally substitute for PNC-1. As Nampt is also secreted, we postulate an evolutionarily conserved extracellular role for NAD(+) biosynthetic enzymes during development and physiology.

  5. Effects of NaCl and seawater induced salinity on survival and reproduction of three soil invertebrate species.

    Science.gov (United States)

    Pereira, C S; Lopes, I; Sousa, J P; Chelinho, S

    2015-09-01

    The increase of global mean temperature is raising serious concerns worldwide due to its potential negative effects such as droughts and melting of glaciers and ice caps leading to sea level rise. Expected impacts on soil compartment include floodings, seawater intrusions and use of saltwater for irrigation, with unknown effects on soil ecosystems and their inhabitants. The present study aimed at evaluating the effects of salinisation on soil ecosystems due to sea level rise. The reproduction and mortality of three standard soil invertebrate species (Folsomia candida, Enchytraeus crypticus, Hypoaspis aculeifer) in standard artificial OECD soil spiked with serial dilutions of seawater/gradient of NaCl were evaluated according to standard guidelines. An increased sensitivity was observed in the following order: H. aculeifer≪E. crypticus≈F. candida consistent with the different exposure pathways: springtails and enchytraeids are exposed by ingestion and contact while mites are mainly exposed by ingestion due to a continuous and thick exoskeleton. Although small differences were observed in the calculated effect electrical conductivity values, seawater and NaCl induced the same overall effects (with a difference in the enchytraeid tests where a higher sensitivity was found in relation to NaCl). The adverse effects described in the present study are observed on soils not considered saline. Therefore, the actual limit to define saline soils (4000 μS cm(-1)) does not reflect the existing knowledge when considering soil fauna. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Temperature Effect Study on Growth and Survival of Pathogenic Vibrio parahaemolyticus in Jinjiang Oyster (Crassostrea rivularis with Rapid Count Method

    Directory of Open Access Journals (Sweden)

    Yuan Wang

    2018-01-01

    Full Text Available The growth of Vibrio parahaemolyticus (V. parahaemolyticus in oysters during postharvest storage increases the possibility of its infection in humans. In this work, to investigate the growth or survival profiles in different media, pathogenic V. parahaemolyticus in APW, Jinjiang oyster (JO, Crassostrea rivularis slurry, and live JO were studied under different temperatures. All the strain populations were counted through our double-layer agar plate (DLAP method. In APW, the pathogenic V. parahaemolyticus showed continuous growth under 15, 25, and 35°C, while a decline in behavior was displayed under 5°C. The similar survival trend of pathogenic V. parahaemolyticus in JO slurry and live JO was observed under 5, 25, and 35°C, except the delayed growth or decline profile compared to APW. Under 15°C, they displayed decline and growth profile in JO slurry and live JO, respectively. These results indicate the different sensitivity of pathogenic V. parahaemolyticus in these matrices to temperature variation. Furthermore, nonpathogenic V. parahaemolyticus displayed little difference in survival profiles when inoculated in live JO under corresponding temperatures. The results indicate that inhibition or promotion effect could be regulated under different storage temperature for both pathogenic and nonpathogenic strains. Besides, the DLAP method showed the obvious quickness and efficiency during the bacteria count.

  7. Effects of temperature and salinity on larval survival and development in the invasive shrimp Palaemon macrodactylus (Caridea: Palaemonidae) along the reproductive season

    Science.gov (United States)

    Guadalupe Vázquez, M.; Bas, Claudia C.; Kittlein, Marcelo; Spivak, Eduardo D.

    2015-05-01

    The invasive shrimp Palaemon macrodactylus is associated mainly with brackish waters. Previous studies raised the question if tolerance to low salinities differs between larvae and adults. To answer this question, the combined effects of two temperatures (20 and 25 °C) and four salinities (5, 12, 23 and 34 psu) on survival and development of larvae that hatched at the beginning, in the midpoint and near the end of a reproductive season (denoted early, middle season and late larvae respectively) were examined. The three types of larvae were able to survive and reach juvenile phase at salinities between 12 and 34 psu and at both temperatures. At 5 psu all larvae died, but 45% molted at least once. Temperature and salinity to a lesser extent, had effects on the duration of development and on the number of larval stages in all larval types. Development was longer at the lower temperature, especially in middle season and late larvae. Most early larvae reached the juvenile phase through 5 larval stages; the number of larval stages of middle season and late larvae was higher at 20 °C and in late larvae also low salinity produced extra stages. Low salinity (12 psu) and, in early and middle season larvae, low temperature produced lighter and smaller individuals. Response of larvae to environmental factors seems to be related in part to the previous conditions (maternal effects and/or embryo development conditions). The narrower salinity tolerance of larvae compared to adults and the ability of zoea I to survive at least some days at 5 psu may be related with an export larval strategy.

  8. Sesquiterpene lactones of Vernonia - influence of glaucolide-A on the growth rate and survival of Lepidopterous larvae.

    Science.gov (United States)

    Jones, Samuel B; Burnett, William C; Coile, Nancy C; Mabry, Tom J; Betkouski, M F

    1979-01-01

    Sesquiterpene lactone glaucolide-A from Vernonia, incorporated in the rearing diets of five species of Lepidoptera, significantly reduced the rate of growth of larvae of the southern armyworm, Spodoptera eridania; fall armyworm, S. frugiperda; and yellowstriped armyworm, S. ornithogalli. Quantitative feeding tests demonstrated that decreased feeding levels and reduced growth resulted from ingestion of a sesquiterpene lactone. Ingestion of glaucolide-A increased the number of days to pupation in four of the species. In the southern armyworm, it significantly reduced pupal weight. Glaucolide-A decidedly reduced percentage of survival of southern and fall armyworms. Yellow woollybear, Diacrisia virginica, and cabbage looper, Trichoplusia ni, larvae were essentially uneffected by the ingestion of the sesquiterpene lactone. Sesquiterpene lactones adversely affect growth rate and survival of certain insects that feed upon plants containing them. They apparently function as defensive products, screening out a portion of the potential herbivores.

  9. Effects of microcosm scaling and food resources on growth and survival of larval Culex pipiens

    Directory of Open Access Journals (Sweden)

    Paradise Christopher J

    2001-08-01

    Full Text Available Abstract Background We used a simple experimental design to test for the effects of microcosm scaling on the growth and survival of the mosquito, Culex pipiens. Microcosm and mesocosm studies are commonly used in ecology, and there is often an assumption that scaling doesn't affect experimental outcomes. The assumption is implicit in the design; choice of mesocosms may be arbitrary or based on convenience or cost. We tested the hypothesis that scale would influence larvae due to depth and surface area effects. Larvae were predicted to perform poorly in microcosms that were both deep and had small openings, due to buildup of waste products, less exchange with the environment, and increased competition. To determine if the choice of scale affected responses to other factors, we independently varied leaf litter quantity, whose effects on mosquitoes are well known. Results We found adverse effects of both a lower wall surface area and lower horizontal surface area, but microcosm scale interacted with resources such that C. pipiens is affected by habitat size only when food resources are scarce. At low resource levels mosquitoes were fewer, but larger, in microcosms with smaller horizontal surface area and greater depth than in microcosms with greater horizontal surface area and shallower depth. Microcosms with more vertical surface area/volume often produced larger mosquitoes; more food may have been available since mosquitoes browse on walls and other substrates for food. Conclusions The interaction between habitat size and food abundance is consequential to aquatic animals, and choice of scale in experiments may affect results. Varying surface area and depth causes the scale effect, with small horizontal surface area and large depth decreasing matter exchange with the surrounding environment. In addition, fewer resources leads to less leaf surface area, and the effects of varying surface area will be greater under conditions of limiting resources

  10. Fecundity, survival, and growth of the seahorse Hippocampus ingens (Pisces: Syngnathidae under semi-controlled conditions

    Directory of Open Access Journals (Sweden)

    A.A Ortega-Salas

    2006-12-01

    Full Text Available Estudiamos la fecundidad, supervivencia, y crecimiento del caballito de mar, Hippocampus ingens en condiciones semi-controladas. Tres machos reproductores silvestres de 14.8, 24.5 y 32.0 g produjeron 1 598, 1 703 y 1 658 jóvenes. La densidad utilizada fue de 12 jóvenes por acuario de 60 l. Se agruparon en 1, 12 y 20 días de nacidos por acuario. La supervivencia fue de 78.5, 38.1 y 41.0 % en 35 días. Se les alimentó con una mezcla de rotíferos B. plicatilis y nauplios de Artemia para después transferirlos a estanques de 100 000 l a una densidad de 50/1 000 l, donde se les alimentó con Artemia adulta durante 60 días más. Crecieron de un promedio de 0.7, 1.5, y 2.7 a 4.5, 5.4 6.7 cm, respectivamente, en 95 días. La temperatura del agua marina utilizada varió de 17 a 23 ºC.We studied fecundity, survival, and growth of the seahorse Hippocampus ingens under semi-controlled conditions. Three wild brood stock mature males of 14.8, 24.5, and 32.0 g released 1 598, 1 703, and 1 658 juveniles. Juvenile stocking densities of 12 were settled in 60-l aquariums in groups of 1, 12, and 20 days old organisms. The rate of survival was 21.5, 61.9, and 59.0 %, respectively, in 35 days. Juveniles were fed a mix diet of rotifers B. plicatilis and Artemia nauplii, then they were transferred to a cement tank of 100 000 l at a density of 50/1 000 l and fed with live adult Artemia for 60 days more. They grew from an average of 0.7, 1.5, and 2.7 to 4.5, 5.4, and 6.7 cm, respectively, in 95 days. The seawater temperature varied from 17 to 23 ºC. Rev. Biol. Trop. 54 (4: 1099-1102. Epub 2006 Dec. 15.

  11. Epidermal Growth Factor Improves Intestinal Integrity and Survival in Murine Sepsis Following Chronic Alcohol Ingestion.

    Science.gov (United States)

    Klingensmith, Nathan J; Yoseph, Benyam P; Liang, Zhe; Lyons, John D; Burd, Eileen M; Margoles, Lindsay M; Koval, Michael; Ford, Mandy L; Coopersmith, Craig M

    2017-02-01

    Epidermal growth factor (EGF) is a cytoprotective protein that improves survival in preclinical models of sepsis through its beneficial effects on intestinal integrity. Alcohol use disorder worsens intestinal integrity and is associated with increased morbidity and mortality in critical illness. We sought to determine whether chronic alcohol ingestion alters the host response to systemic administration of EGF in sepsis. Six-week-old FVB/N mice were randomized to receive 20% alcohol or water for 12 weeks. All mice then underwent cecal ligation and puncture to induce polymicrobial sepsis. Mice were then randomized to receive either intraperitoneal injection of EGF (150 μg/kg/day) or normal saline. Water-fed mice given EGF had decreased 7-day mortality compared with water-fed mice (18% vs. 55%). Alcohol-fed mice given EGF also had decreased 7-day mortality compared with alcohol-fed mice (48% vs. 79%). Notably, while systemic EGF improved absolute survival to a similar degree in both water-fed and alcohol-fed mice, mortality was significantly higher in alcohol+EGF mice compared with water+EGF mice. Compared with water-fed septic mice, alcohol-fed septic mice had worsened intestinal integrity with intestinal hyperpermeability, increased intestinal epithelial apoptosis, decreased proliferation and shorter villus length. Systemic administration of EGF to septic alcohol-fed mice decreased intestinal permeability compared with septic alcohol-fed mice given vehicle, with increased levels of the tight junction mediators claudin-5 and JAM-A. Systemic administration of EGF to septic alcohol-fed mice also decreased intestinal apoptosis with an improvement in the Bax/Bcl-2 ratio. EGF also improved both crypt proliferation and villus length in septic alcohol-fed mice. EGF administration resulted in lower levels of both pro- and anti-inflammatory cytokines monocyte chemoattractant protein-1, tumor necrosis factor, and interleukin 10 in alcohol-fed mice. EGF is therefore

  12. Gastropod growth and survival as bioindicators of stress associated with high nutrients in the intertidal of a shallow temperate estuary

    Science.gov (United States)

    Marsden, Islay D.; Baharuddin, Nursalwa

    2015-04-01

    The effects of multiple stressors on estuarine organisms are not well understood. Using cage experiments we measured the survival and growth of the pulmonate gastropod Amphibola crenata at five locations which differed contaminant levels. Water nutrients came from a nearby sewage treatment works and the sediment contained low levels of trace metals. Over 6 weeks of exposure, sediment surface chlorophyll levels varied amongst locations. The Chl a values were positively correlated with sediment N and P and trace metals As, Cd, Cu, Pb and Zn. Pulmonate survival depended on location, highest mortality was from a site close to the treatment plant and mortality rate of large individuals decreased significantly with distance away from it. For four locations, medium A. crenata had higher survival than small (juveniles) or adults. Growth rates of small individuals exceeded those for medium and large A. crenata. The mean length increment/week for medium gastropods ranged between 0.49 and 1.11 mm and was negatively correlated with the amount of Chl a in the surface sediment, suggesting the negative effects of eutrophication on gastropod growth. Growth rate of the pulmonate was not correlated with nutrient concentration or trace metal concentrations in the sediment. The dry weight condition index (CI) did not correlate with the growth rate, and for medium individuals, was unaffected by any of the environmental variables. The CI of small individuals was negatively affected by increasing water nutrient levels and the CI of large individuals negatively affected by increasing sediment nutrients and trace metal concentrations. The results from this study suggest that gastropod growth and survival could be used as tools to monitor the effects of changing nutrient levels and recovery from eutrophication within temperate estuaries.

  13. Effect of chronic ingestion of tritiated water and tritium organically bound in food on growth and reproductive functions of rats

    International Nuclear Information System (INIS)

    Pietrzak-Flis, Z.; Radwan, I.

    1982-01-01

    An effect of chronic ingestion of tritiated water and tritiated food on growth and reproduction of Wistar rats was evaluated. The animals were exposed during one or three successive generations. Ingestion of tritiated water at activity of 185.0 and 370.0 kBq/ml or tritiated food at activity of 144.3 kBq/g affected growth of the first generation (F 1 ) rats. In groups exposed to tritiated water the effect was transient. Exposure to tritiated food at 48.1 kBq/g or to tritiated water at the 37.0 kBq/ml affected the growth of F 2 generation rats only. A significant reduction in a relative testis tests weight was observed in a group exposed to tritiated water at activity of 370.0 kBq/ml, while sperm production was affected in all exposed groups. Ingestion of tritiated food caused higher reduction in sperm count than tritiated water. The effect of tritium on growth of rats and ability for sperm production depended on the absorbed dose and the form of ingested tritium. (author)

  14. Does reproduction accelerate the growth of eye lens mass in female voles?

    Czech Academy of Sciences Publication Activity Database

    Jánová, Eva; Havelková, Dana; Tkadlec, Emil

    2007-01-01

    Roč. 137, č. 1 (2007), s. 85-88 ISSN 0777-6276 R&D Projects: GA ČR GA206/04/2003; GA ČR(CZ) GD524/05/H536 Institutional research plan: CEZ:AV0Z60930519 Keywords : age estimation * eye lens mass * reproduction Subject RIV: EH - Ecology, Behaviour Impact factor: 0.433, year: 2007 http://www.naturalsciences.be/institute/associations/rbzs_website/bjz/back/pdf/BJZ%20137(1)/Volume%20137(1),%20pp.%2085-88.pdf

  15. Germination, survival and growth of three vascular plants on biological soil crusts from a Mexican tropical desert.

    Science.gov (United States)

    Godínez-Alvarez, H; Morín, C; Rivera-Aguilar, V

    2012-01-01

    Information about the effects of biological soil crusts (BSC) on germination, seedling survival and growth of vascular plants is controversial because they can have positive, neutral or negative effects. This controversy may be because most studies conducted until now have just analysed one or two recruitment stages independently. To understand the BSC effects on vascular plants, it is necessary to consider each stage of the recruitment process and synthesise all this information. The goal of this study was twofold. First, we analyse germination, seedling survival and growth of three vascular plants (Agave marmorata, Prosopis laevigata and Neobuxbaumia tetetzo) on BSC (cyanobacteria and mixed crust) from a tropical desert region of south-central México. Second, we synthesise the information to determine the total effect of BSC on plant species performance. We conducted experiments under controlled conditions to evaluate the proportion of germinated seeds, proportion of surviving seedlings and seedling dry weight in BSC and bare soil. Results showed that BSC have different effects on germination, seedling survival and growth of plant species. Plant species performance was qualitatively higher on BSC than bare soil. The highest performance of A. marmorata and P. laevigata was observed on cyanobacteria and mixed crusts, respectively. The highest performance of N. tetetzo was on both crust types. © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.

  16. Effect of parental age and associated size on fecundity, growth and survival in the yellow seahorse Hippocampus kuda.

    Science.gov (United States)

    Dzyuba, Borys; Van Look, Katrien J W; Cliffe, Alex; Koldewey, Heather J; Holt, William V

    2006-08-01

    Seahorses, together with the pipefishes (Family Syngnathidae), are the only vertebrates in which embryonic development takes place within a specialised body compartment, the brood pouch, of the male instead of the female. Embryos develop in close association with the brood pouch epithelium in a manner that bears some resemblance to embryo-placental relationships in mammals. We have explored the hypothesis that parental body size and age should affect offspring postnatal growth and survival if brood pouch quality impacts upon prenatal embryonic nutrition or respiration. Using an aquarium population of the yellow seahorse, Hippocampus kuda, we show here that large parents produce offspring whose initial postnatal growth rates (weeks one to three) were significantly higher than those of the offspring of younger and smaller parents. Whereas 90% of offspring from the larger parents survived for the duration of the study (7 weeks), less that 50% of offspring from smaller parents survived for the same period. For the offspring of large parents, growth rates from individual males were negatively correlated with the number of offspring in the cohort (r=-0.82; P0.9). Observations of embryos within the pouch suggested that when relatively few embryos are present they may attach to functionally advantageous sites and thus gain physiological support during gestation. These results suggest that male body size, and pouch size and function, may influence the future fitness and survival of their offspring.

  17. Specificity of induced defenses, growth, and reproduction in lima bean (Phaseolus lunatus) in response to multispecies herbivory.

    Science.gov (United States)

    Moreira, Xoaquín; Abdala-Roberts, Luis; Hernández-Cumplido, Johnattan; Cuny, Maximilien A C; Glauser, Gaetan; Benrey, Betty

    2015-08-01

    • Following herbivore attack, plants can either reduce damage by inducing defenses or mitigate herbivory effects through compensatory growth and reproduction. It is increasingly recognized that such induced defenses in plants are herbivore-specific, but less is known about the specificity of compensatory responses. Damage by multiple herbivores may also lead to synergistic effects on induction and plant fitness that differ from those caused by a single herbivore species. Although largely unstudied, the order of arrival and damage by different herbivore species might also play an important role in the impacts of herbivory on plants.• We investigated the specificity of defense induction (phenolics) and effects on growth (number of stems and leaves) and reproduction (number of seeds, seed mass, and germination rate) from feeding by two generalist leaf-chewing herbivores (Spodoptera eridania and Diabrotica balteata) on Phaseolus lunatus plants and evaluated whether simultaneous attack by both herbivores and their order of arrival influenced such dynamics.• Herbivory increased levels of leaf phenolics, but such effects were not herbivore-specific. In contrast, herbivory enhanced seed germination in an herbivore-specific manner. For all variables measured, the combined effects of both herbivore species did not differ from their individual effects. Finally, the order of herbivore arrival did not influence defense induction, plant growth, or seed number but did influence seed mass and germination.• Overall, this study highlights novel aspects of the specificity of plant responses induced by damage from multiple species of herbivores and uniquely associates such effects with plant lifetime fitness. © 2015 Botanical Society of America, Inc.

  18. Poly-β-hydroxybutyrate (PHB) accumulating Bacillus spp. improve the survival, growth and robustness of Penaeus monodon (Fabricius, 1798) postlarvae.

    Science.gov (United States)

    Laranja, Joseph Leopoldo Q; Ludevese-Pascual, Gladys L; Amar, Edgar C; Sorgeloos, Patrick; Bossier, Peter; De Schryver, Peter

    2014-10-10

    Low larval survival resulting from suboptimal culture conditions and luminous vibriosis poses a major problem for the larviculture of penaeid shrimp. In this study, a poly-β-hydroxybutyrate (PHB) accumulating mixed bacterial culture (mBC; 48.5% PHB on cell dry weight) and two PHB accumulating bacterial isolates, Bacillus sp. JL47 (54.7% PHB on cell dry weight) and Bacillus sp. JL1 (45.5% PHB on cell dry weight), were obtained from a Philippine shrimp culture pond and investigated for their capacity to improve growth, survival and robustness of Penaeus monodon postlarvae (PL). Shrimp PL1 and shrimp PL30 were provided with the PHB containing bacterial cultures in the feed for 30 days followed by, respectively, a challenge with pathogenic Vibrio campbellii and exposure to a lethal dose of ammonia. Prior to the pathogenic challenge or ammonia stress, growth and survival were higher for shrimp receiving the PHB accumulating bacteria as compared to shrimp receiving diets without bacterial additions. After exposure to the pathogenic challenge the shrimp fed PHB accumulating bacteria showed a higher survival as compared to non-treated shrimp, suggesting an increase in robustness for the shrimp. Similar effects were observed when shrimp PL30 were provided with the PHB accumulating bacterial cultures during a challenge with pathogenic V. campbellii through the water. The survival of shrimp exposed to lethal ammonia stress showed no significant difference between PHB accumulating bacteria-fed shrimp and non-PHB treated shrimp. The data illustrate that bacilli capable of accumulating PHB can provide beneficial effects to P. monodon post-larvae during culture in terms of growth performance, survival and resistance against pathogenic infection and ammonia stress. Further investigations are required to verify the PHB effect of the bacterial cultures on the shrimp. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Altered serotonin physiology in human breast cancers favors paradoxical growth and cell survival.

    Science.gov (United States)

    Pai, Vaibhav P; Marshall, Aaron M; Hernandez, Laura L; Buckley, Arthur R; Horseman, Nelson D

    2009-01-01

    The breast microenvironment can either retard or accelerate the events associated with progression of latent cancers. However, the actions of local physiological mediators in the context of breast cancers are poorly understood. Serotonin (5-HT) is a critical local regulator of epithelial homeostasis in the breast and other organs. Herein, we report complex alterations in the intrinsic mammary gland serotonin system of human breast cancers. Serotonin biosynthetic capacity was analyzed in human breast tumor tissue microarrays using immunohistochemistry for tryptophan hydroxylase 1 (TPH1). Serotonin receptors (5-HT1-7) were analyzed in human breast tumors using the Oncomine database. Serotonin receptor expression, signal transduction, and 5-HT effects on breast cancer cell phenotype were compared in non-transformed and transformed human breast cells. In the context of the normal mammary gland, 5-HT acts as a physiological regulator of lactation and involution, in part by favoring growth arrest and cell death. This tightly regulated 5-HT system is subverted in multiple ways in human breast cancers. Specifically, TPH1 expression undergoes a non-linear change during progression, with increased expression during malignant progression. Correspondingly, the tightly regulated pattern of 5-HT receptors becomes dysregulated in human breast cancer cells, resulting in both ectopic expression of some isoforms and suppression of others. The receptor expression change is accompanied by altered downstream signaling of 5-HT receptors in human breast cancer cells, resulting in resistance to 5-HT-induced apoptosis, and stimulated proliferation. Our data constitutes the first report of direct involvement of 5-HT in human breast cancer. Increased 5-HT biosynthetic capacity accompanied by multiple changes in 5-HT receptor expression and signaling favor malignant progression of human breast cancer cells (for example, stimulated proliferation, inappropriate cell survival). This occurs

  20. Survival significance of epidermal growth factor receptor tyrosine kinase inhibitors and current staging system for survival after recurrence in patients with completely resected lung adenocarcinoma

    Science.gov (United States)

    Saji, Hisashi; Sakai, Hiroki; Kimura, Hiroyuki; Miyazawa, Tomoyuki; Marushima, Hideki; Nakamura, Haruhiko

    2017-01-01

    Objective We previously reported that the staging system and epidermal growth factor receptor (EGFR) mutation status are key factors for treatment strategy and predicting survival. However, the significance of these factors as predictors of overall survival (OS) and postoperative recurrence survival (PRS) has not been sufficiently elucidated. The objective here was to investigate EGFR mutation status and p-stage, which affect PRS and OS in patients with completely resected lung adenocarcinoma, using a different database. Patients and methods We retrospectively reviewed 56 consecutive lung adenocarcinoma patients with disease recurrence in St. Marianna University Hospital between January 2010 and December 2014. Results EGFR mutants (M) were detected in 16/56 patients (29%). The patients with EGFR M had a better OS than those with EGFR wild-type (WT) status (5-year survival: 50.3% vs 43.1, P=0.133). There was no significant difference in the 3-year recurrence-free survival rate between patients with M and WT (6.3% vs 7.7%, P=0.656), and the patients with EGFR M had a significantly better 3-year PRS than those with WT (77.4% vs 51.7%, P=0.033). The 3-year PRS rate for patients with M/pathologic stage (p-stage) I–II (87.5%) was better than that for patients with M/p-stage III (60.0%), WT/p-stage I–II (52.7%), and WT/p-stage III (43.8%). There was a significant difference between patients with M/p-stage I and WT/p-stage I–II or WT/p-stage III (P=0.021 and 0.030, respectively). During the study period, of the 16 patients with mutants, 12 patients (75%) received EGFR-tyrosine kinase inhibitor (TKI) therapy and among the 40 patients with WT, no patient received EGFR-TKI therapy. Multivariate survival analysis showed that patients with EGFR-TKI therapy had a statistically significant association with favorable PRS (hazard ratio 0.271; 95% confidence interval 0.074–1.000; P=0.050). Conclusion EGFR status and p-stage were found to be essential prognostic factors for

  1. Effect of systematic parturition induction of long gestation Holstein dairy cows on calf survival, cow health, production, and reproduction on a commercial farm

    Science.gov (United States)

    Villarroel, Aurora; Lane, V. Michael

    2010-01-01

    The objective of this study was to evaluate the effect of parturition induction on dairy cattle with long gestation (past due-date) single pregnancies on calf survivability, cow health, production, and reproduction. There was an induction period during which all cows and heifers reaching 282 days of gestation were induced with dexamethasone (n = 614). Control cows calved the year after, had a gestation length > 282 d and were not induced (n = 508). As the induced and non-induced groups were not contemporaneous, data were standardized using the ratio between the herd baselines for each period. Multivariate analyses of the data showed that induced cows were 1.41 times more likely (P = 0.020) to become pregnant in the lactation following the studied calving than non-induced cows with long gestation. There was no difference in the risk of difficult calvings, stillbirths, culling due to reproductive reasons, average milk production, average days open or risk of abortion in the following lactation between induced and non-induced cows. There seemed to be a relationship between parturition induction and a lower risk of post-partum death, although this was not statistically significant (P = 0.162), because including induction as a factor in the model markedly improved the fit of the data. There was no information on incidence of retained placenta (RP) for the non-induced group. In conclusion, parturition induction resulted in more cows becoming pregnant and a seemingly lower risk of post-spartum death without affecting calving difficulty, calf viability, or milk production. PMID:20592844

  2. Effect of gamma radiation on the growth, survival, hematology and histological parameters of rainbow trout (Oncorhynchus mykiss) larvae

    Energy Technology Data Exchange (ETDEWEB)

    Oujifard, Amin, E-mail: oujifard.amin@gmail.com [Fisheries Department, Faculty of Agriculture and Natural Resources, Persian Gulf University, Borazjan, Bushehr (Iran, Islamic Republic of); Amiri, Roghayeh [Department of Veterinary, Agricultural Medical and Industrial Research School, Nuclear Science and Technology Research Institute, AEOI, Karaj (Iran, Islamic Republic of); Shahhosseini, Gholamreza [Fisheries Department, Faculty of Natural Resources and Marine Sciences, TarbiatModares University, Noor, Mazandaran (Iran, Islamic Republic of); Davoodi, Reza [Fisheries Department, Faculty of Agriculture and Natural Resources, Persian Gulf University, Borazjan, Bushehr (Iran, Islamic Republic of); Moghaddam, Jamshid Amiri [Fisheries Department, Faculty of Natural Resources and Marine Sciences, TarbiatModares University, Noor, Mazandaran (Iran, Islamic Republic of)

    2015-08-15

    Highlights: • Incrementing of gamma radiation reveals the negative effects on fish larvae. • Radiation adversely affected the weight, blood cells and intestinal morphology of the larvae. • No mortality was observed at low dosage of gamma radiation on fish larvae. - Abstract: Effects of low (1, 2.5 and 5 Gy) and high doses (10, 20 and 40 Gy) of gamma radiation were examined on the growth, survival, blood parameters and morphological changes of the intestines of rainbow trout (Oncorhynchus mykiss) larvae (103 ± 20 mg) after 12 weeks of exposure. Negative effects of gamma radiation on growth and survival were observed as radiation level and time increased. Changes were well documented at 10 and 20 Gy. All the fish were dead at the dose of 40 Gy. In all the treatments, levels of red blood cells (RBC), hematocrit (HCT) and hemoglobin (HB) were significantly (P < 0.05) declined as the irradiation levels increased, whereas the amount of mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) did not change. No significant differences (P > 0.05) were found in the levels of white blood cells (WBC), lymphocytes and monocytes. Destruction of the intestinal epithelium cells was indicated as the irradiation levels increased to 1 Gy and above. The highest levels of growth, survival, specific growth rate (SGR), condition factor (CF) and protein efficiency rate (PER) were obtained in the control treatment. The results showed that gamma rays can be a potential means for damaging rainbow trout cells.

  3. Signal transducer and activator of transcription 3 activation is associated with bladder cancer cell growth and survival

    Directory of Open Access Journals (Sweden)

    Hsieh Fu-Chuan

    2008-10-01

    Full Text Available Abstract Background Constitutive activation of signal transducer and activator of transcription 3 (Stat3 signaling pathway plays an important role in several human cancers. Activation of Stat3 is dependent on the phosphorylation at the tyrosine residue 705 by upstream kinases and subsequent nuclear translocation after dimerization. It remains unclear whether oncogenic Stat3 signaling pathway is involved in the oncogenesis of bladder cancer. Results We found that elevated Stat3 phosphorylation in 19 of 100 (19% bladder cancer tissues as well as bladder cancer cell lines, WH, UMUC-3 and 253J. To explore whether Stat3 activation is associated with cell growth and survival of bladder cancer, we targeted the Stat3 signaling pathway in bladder cancer cells using an adenovirus-mediated dominant-negative Stat3 (Y705F and a small molecule compound, STA-21. Both prohibited cell growth and induction of apoptosis in these bladder cancer cell lines but not in normal bladder smooth muscle cell (BdSMC. The survival inhibition might be mediated through apoptotic caspase 3, 8 and 9 pathways. Moreover, down-regulation of anti-apoptotic genes (Bcl-2, Bcl-xL and survivin and a cell cycle regulating gene (cyclin D1 was associated with the cell growth inhibition and apoptosis. Conclusion These results indicated that activation of Stat3 is crucial for bladder cancer cell growth and survival. Therefore, interference of Stat3 signaling pathway emerges as a potential therapeutic approach for bladder cancer.

  4. Effect of gamma radiation on the growth, survival, hematology and histological parameters of rainbow trout (Oncorhynchus mykiss) larvae

    International Nuclear Information System (INIS)

    Oujifard, Amin; Amiri, Roghayeh; Shahhosseini, Gholamreza; Davoodi, Reza; Moghaddam, Jamshid Amiri

    2015-01-01

    Highlights: • Incrementing of gamma radiation reveals the negative effects on fish larvae. • Radiation adversely affected the weight, blood cells and intestinal morphology of the larvae. • No mortality was observed at low dosage of gamma radiation on fish larvae. - Abstract: Effects of low (1, 2.5 and 5 Gy) and high doses (10, 20 and 40 Gy) of gamma radiation were examined on the growth, survival, blood parameters and morphological changes of the intestines of rainbow trout (Oncorhynchus mykiss) larvae (103 ± 20 mg) after 12 weeks of exposure. Negative effects of gamma radiation on growth and survival were observed as radiation level and time increased. Changes were well documented at 10 and 20 Gy. All the fish were dead at the dose of 40 Gy. In all the treatments, levels of red blood cells (RBC), hematocrit (HCT) and hemoglobin (HB) were significantly (P < 0.05) declined as the irradiation levels increased, whereas the amount of mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) did not change. No significant differences (P > 0.05) were found in the levels of white blood cells (WBC), lymphocytes and monocytes. Destruction of the intestinal epithelium cells was indicated as the irradiation levels increased to 1 Gy and above. The highest levels of growth, survival, specific growth rate (SGR), condition factor (CF) and protein efficiency rate (PER) were obtained in the control treatment. The results showed that gamma rays can be a potential means for damaging rainbow trout cells

  5. Effects of dietary ABATE® on reproductive success, duckling survival, behavior, and clinical pathology in game-farm mallards

    Science.gov (United States)

    Franson, J. Christian; Spann, James W.; Heinz, Gary; Bunck, Christine M.; Lamont, Thair

    1983-01-01

    Forty-four pairs of game-farm mallards (Anas platyrhynchos) were fed ABATE® 4E (temephos) to yield 0, 1, or 10 ppm ABATE® beginning before the initiation of lay, and terminating when ducklings were 21 days of age. The mean interval between eggs laid was greater for hens fed 10 ppm ABATE® than for controls. Clutch size, fertility, hatchability, nest attentiveness of incubating hens, and avoidance behavior of ducklings were not significantly affected by ABATE® ingestion. The percentage survival of ducklings to 21 days of age was significantly lower in both treated groups than in controls, but brain acetylcholinesterase (AChE) activity was not inhibited in young which died before termination of the study. In 21-day-old ducklings, aspartate aminotransferase (AST) activity increased and plasma nonspecific cholinesterase (ChE) activity was inhibited by about 20% in both treatment groups, but there were no significant differences in brain AChE or plasma alanine aminotransferase (ALT) activities, or plasma uric acid concentration. Clinical chemistry values of adults were not affected. No ABATE®, ABATE® sulfoxide, or ABATE® sulfone residues were found in eggs or tissue samples.

  6. Thalli Growth, Propagule Survival, and Integrated Physiological Response to Nitrogen Stress of Ramalina calicaris var. japonica in Shennongjia Mountain (China

    Directory of Open Access Journals (Sweden)

    Chuan-Hua Wang

    2018-05-01

    Full Text Available In this study, effects of nitrogen (N availability on growth, survival of Ramalina calicaris var. japonica, and whether it respond nitrogen stress in an integrated physiological way was evaluated. Thalli growth and propagule survival, thalli N and phosphorus (P content, and activity of phosphomonoesterase (PME of R. calicaris var. japonica were determined in a field experiment. Its differentiate adsorption in ammonia and nitrate, the activity of glutamine synthetase (GSA and nitrate reductase (NRA also were investigated in a series of indoor experiments. The results showed that N deposition significantly decreased the growth and survival of this lichen, and the N sensitivity threshold was suggested at 6.0 kg N⋅ha-1⋅y-1. When the N deposition increased from 8.59 kg N⋅ha-1⋅y-1 to 14.24, 20.49, 32.99 and 57.99 kg N⋅ha-1⋅y-1, the growth rates of lichen thalli decreased by 26.47, 39.01, 52.18 and 60.3%, respectively; Whereas the survival rate of the lichen propagules decreased from 92.8% of control (0.0 kg N⋅ha-1⋅y-1 to 10.7% of 50.0 kg N⋅ha-1⋅y-1, when they were treated with 0.00, 6.25, 12.5, 25.0, and 50.0 kg N⋅ha-1⋅y-1 deposition. Compared with an adequate adsorption of ammonium N, no nitrate adsorption occurred when thalli was submerged in solution lower than 0.4 mM. Our results also suggested that thalli total nitrogen, N:P ratio increased with N availability, and the activity of PME was significantly correlated with thalli total nitrogen. These all indicated that phosphorus limitation occurred when R. calicaris var. japonica treated with higher nitrogen deposition. Compared with slightly effects of NRA, GSA of R. calicaris var. japonica responded nitrogen availability significantly; In addition, GSA and NRA negatively correlated with thalli growth rate and propagule survival significantly. These results indicated that nitrogen stress do decrease growth and survival of R. calicaris var. japonica, and lichen would be

  7. The growth of vegetative and reproductive structures (leaves and silks) respond similarly to hydraulic cues in maize.

    Science.gov (United States)

    Turc, Olivier; Bouteillé, Marie; Fuad-Hassan, Avan; Welcker, Claude; Tardieu, François

    2016-10-01

    The elongation of styles and stigma (silks) of maize (Zea mays) flowers is rapid (1-3 mm h(-1) ), occurs over a short period and plays a pivotal role in reproductive success in adverse environments. Silk elongation rate was measured using displacement transducers in 350 plants of eight genotypes during eight experiments with varying evaporative demand and soil water status. Measured time courses revealed that silk elongation rate closely followed changes in soil water status and evaporative demand, with day-night alternations similar to those in leaves. Day-night alternations were steeper with high than with low plant transpiration rate, manipulated via evaporative demand or by covering part of the leaf area. Half times of changes in silk elongation rate upon changes in evaporative demand or soil water status were 10-30 min, similar to those in leaves. The sensitivity of silk elongation rate to xylem water potential was genetically linked to that of leaf elongation rate. Lines greatly differed for these sensitivities. These results are consistent with a common hydraulic control of expansive growth in vegetative and reproductive structures upon changes in environmental conditions via a close connection with the xylem water potential. They have important implications for breeding, modelling and phenotyping. © 2016 INRA. New Phytologist © 2016 New Phytologist Trust.

  8. Effect of rosiglitazone on insulin resistance, growth factors, and reproductive disturbances in women with polycystic ovary syndrome.

    Science.gov (United States)

    Belli, Susana H; Graffigna, Mabel N; Oneto, Adriana; Otero, Patricia; Schurman, Leon; Levalle, Oscar A

    2004-03-01

    To evaluate the effects of rosiglitazone on insulin resistance, growth factors, and reproductive disturbances in women with polycystic ovary syndrome (PCOS). Prospective study. Women with PCOS attending as outpatients of the Endocrine Division, Hospital Durand, Buenos Aires. Twenty-four insulin-resistant women with PCOS. Hormonal evaluations and a standardized oral glucose tolerance test before and after a 3-month trial of 4 mg of rosiglitazone daily. Serum LH, FSH, T, IGF-1, IGFBP-1, IGFBP-3, leptin, 17alpha-hydroxyprogesterone, insulin, and glucose concentrations. The area under insulin curve (AUC-insulin), the HOMA index (insulin resistance), the QUICKI index (insulin sensitivity), and the beta-cell function were calculated. Body mass index (BMI) and the waist/hip ratio were evaluated. A significant decrease was observed in serum fasting insulin, AUC insulin, HOMA index, beta-cell function, IGF-1, LH, and waist/hip ratio. The QUICKI index and IGFBP-1 increased significantly. Serum sex hormone-binding globulin, androgens, leptin, IGFBP-3, and BMI remained unchanged. Twenty-two of 23 females had their menses restored, and three patients became pregnant. One patient was excluded because she became pregnant at the second month. Associated with the decrease in LH, rosiglitazone improved insulin-resistance parameters and normalized the menstrual cycle, which suggests that this drug could improve the endocrine-reproductive condition in insulin-resistant women with PCOS.

  9. Growth, survival, and peptidolytic activity of Lactobacillus plantarum I91 in a hard-cheese model.

    Science.gov (United States)

    Bergamini, C V; Peralta, G H; Milesi, M M; Hynes, E R

    2013-09-01

    In this work, we studied the growth, survival, and peptidolytic activity of Lactobacillus plantarum I91 in a hard-cheese model consisting of a sterile extract of Reggianito cheese. To assess the influence of the primary starter and initial proteolysis level on these parameters, we prepared the extracts with cheeses that were produced using 2 different starter strains of Lactobacillus helveticus 138 or 209 (Lh138 or Lh209) at 3 ripening times: 3, 90, and 180 d. The experimental extracts were inoculated with Lb. plantarum I91; the control extracts were not inoculated and the blank extracts were heat-treated to inactivate enzymes and were not inoculated. All extracts were incubated at 34°C for 21 d, and then the pH, microbiological counts, and proteolysis profiles were determined. The basal proteolysis profiles in the extracts of young cheeses made with either strain tested were similar, but many differences between the proteolysis profiles of the extracts of the Lh138 and Lh209 cheeses were found when riper cheeses were used. The pH values in the blank and control extracts did not change, and no microbial growth was detected. In contrast, the pH value in experimental extracts decreased, and this decrease was more pronounced in extracts obtained from either of the young cheeses and from the Lh209 cheese at any stage of ripening. Lactobacillus plantarum I91 grew up to 8 log during the first days of incubation in all of the extracts, but then the number of viable cells decreased, the extent of which depended on the starter strain and the age of the cheese used for the extract. The decrease in the counts of Lb. plantarum I91 was observed mainly in the extracts in which the pH had diminished the most. In addition, the extracts that best supported the viability of Lb. plantarum I91 during incubation had the highest free amino acids content. The effect of Lb. plantarum I91 on the proteolysis profile of the extracts was marginal. Significant changes in the content of free

  10. Effects of culture conditions on the growth and reproduction of Gut Weed, Ulva intestinalis Linnaeus (Ulvales, Chlorophyta

    Directory of Open Access Journals (Sweden)

    Rapeeporn Ruangchuay

    2012-11-01

    Full Text Available In vitro cultivation of Gut Weed, Ulva intestinalis Linnaeus, was experimentally studied to support its near optimalfarming, with potential impact in Thailand on its direct use as human food or its co-cultures in shrimp farming.Germling clusters (2 weeks old and 7.50±2.98 mm long were seeded into 500 mL flasks and biomass growth rateoptimized with respect to the main controllable factors; seedling density, salinity, light intensity, and temperature. These factorswere assumed to each have an optimal value independent of the others, and the factors were optimized one at a time. Themaximum growth at three to four weeks of cultivation was obtained at the factor levels of 0.05 gL-1, 20 ppt, 80 mol photonm-2s-1 and 25°C. Early zoosporangia were obtained from 2nd to 4th weeks. The relative growth rate ranged from 9.47 to 22.18 %day-1, and only asexual reproduction of U. intestinalis was observed under these culture conditions.

  11. Limnology of nine small lakes, Matanuska-Susitna Borough, Alaska, and the survival and growth rates of rainbow trout

    Science.gov (United States)

    Woods, P.F.

    1985-01-01

    The survival and growth rates of rainbow trout (Salmo gairdnieri) were concurrently measured with selected limnological characteristics in nine small (surface area Gasterosteus aculeatus) also influenced survival of rainbow trout but their effects were overshadowed by winterkill. Predictive capability was also reduced because of inconsistencies in rankings generated by each of the four limnological variables chosen as indicators of potential biological productivity. A lake ranked low in productivity by one variable was commonly ranked high in productivity by another variable. The survivability of rainbow trout stocked in lakes such as these nine may be a more important indicator of potential biomass production than are indicators of lake fertility. Assessments of a lake 's susceptibility to winterkill and the degree of competition with threespine stickleback are suggested as important topics for additional research. (Author 's abstract)

  12. Growth and survival of larval and early juvenile lesser sandeel in patchy prey field in the North Sea: An examination using individual-based modelling

    DEFF Research Database (Denmark)

    Gürkan, Zeren; Christensen, Asbjørn; Deurs, Mikael van

    2012-01-01

    -stages in the North Sea. Simulations of patchiness related starvation mortality are able to explain observed patterns of variation in sandeel growth. Reduced prey densities within patches decrease growth and survival rate of larvae and match–mismatch affect growth and survival of larvae with different hatch time due...... by modeling copepod size spectra dynamics and patchiness based on particle count transects and Continuous Plankton Recorder time series data. The study analyzes the effects of larval hatching time, presence of zooplankton patchiness and within patch abundance on growth and survival of sandeel early life...

  13. Importance of birthcoat for lamb survival and growth in the Romane sheep breed extensively managed on rangelands.

    Science.gov (United States)

    Allain, D; Foulquié, D; Autran, P; Francois, D; Bouix, J

    2014-01-01

    The Romane sheep breed proved to be adapted to harsh conditions with high prolificacy and lamb survival in outdoor farming, even under bad climate conditions. This breed shows large variability in its fleece type at birth and it has been suggested that lamb survival could be related to birthcoat type. The aim of the present study was to: i) characterize the coat of the lamb at birth and quantify lamb survival in relation to the birthcoat type and its protective properties concerning heat loss in the Romane breed raised under permanent exposure outdoors from birth, and ii) estimate genetic parameters of birthcoat type in relation to lamb survival and live body weight. A total of 7,880 lambs from 104 sires and 1,664 dams were used in a 14-yr experiment. The pedigree file included 9,625 individuals over 15 generations. Birthcoat type, coat surface temperature, coat depth, lamb survival, and growth were measured from birth to weaning. Weather data (temperature, wind speed, relative humidity, and precipitation) were recorded daily during lambing time. Two types of coats were observed at birth: hairy coat (62.9% of lambs) with a long coat depth (average 23.3 mm) or woolly 1 (37.1% of lambs) with a short coat depth (average 8.3 mm). Birthcoat type was an important factor affecting lamb survival and growth from birth in the Romane breed. Total mortality rate was significantly less in hairy-bearing coat lambs than in short-woolly coat ones: 7.0% vs. 9.6%, 11.6 % vs. 14.8%, and 15.7 % vs. 20.1 % at 2, 10, and 50 d, respectively, and the relative risks of death increased by 37%, 67%, and 46 % at 2, 10, and 50 d of age, respectively, in short-woolly lambs. At birth, a significant lower coat surface temperature, indicating less heat loss, was observed in long-hairy coat lambs compared with others (21.1°C vs. 26.1°C). Heavier body weights and better growth performances up to the age of 50 d were observed in long-hairy-bearing coat lambs. Lamb survival was positively correlated

  14. Salmonella enterica serovar Enteritidis and Listeria monocytogenes in mango (Mangifera indica L.) pulp: growth, survival and cross-contamination.

    Science.gov (United States)

    Penteado, Ana L; de Castro, M Fernanda P M; Rezende, Ana C B

    2014-10-01

    This study examined the ability of Salmonella enterica serovar Enteritidis and Listeria monocytogenes to grow or survive in mango pulp stored at -20°C, 4°C, 10°C and 25°C, as well as to cross-contaminate mangoes by means of a knife contaminated with different levels of these pathogens. At 25°C lag phase durations of 19 h and 7.2 h and generation times of 0.66 and 1.44 were obtained, respectively, for S. Enteritidis and L. monocytogenes. At 10°C only the growth of L. monocytogenes was observed. At 4°C both bacteria survived for 8 days. At -20°C S. Enteritidis was able to survive for 5 months while L. monocytogenes survived for 8 months. Cross-contamination was observed for knives contaminated with 10⁶, 10⁵ and 10⁴ CFU mL⁻¹ of S. Enteritidis and 10⁶ and 10⁵ CFU mL⁻¹ of L. monocytogenes. Both microorganisms can grow well in mango pulp at 25°C, thus lower temperatures for the maintenance of the pulps are crucial to avoid growth of these microorganisms. A refrigeration temperature of 10°C will avoid only the growth of S. Enteritidis. Thus good handling practices should be rigidly enforced to avoid any contamination as even at refrigeration and freezing temperatures survival of these pathogens may occur. © 2014 Society of Chemical Industry.

  15. Short- and long-term reproductive effects of prenatal and lactational growth restriction caused by maternal diabetes in male rats

    Directory of Open Access Journals (Sweden)

    Amorim Elaine MP

    2011-12-01

    Full Text Available Abstract Background A suboptimal intrauterine environment may have a detrimental effect on gonadal development and thereby increases the risk for reproductive disorders and infertility in adult life. Here, we used uncontrolled maternal diabetes as a model to provoke pre- and perinatal growth restriction and evaluate the sexual development of rat male offspring. Methods Maternal diabetes was induced in the dams through administration of a single i.v. dose of 40 mg/kg streptozotocin, 7 days before mating. Female rats presenting glycemic levels above 200 mg/dL after the induction were selected for the experiment. The male offspring was analyzed at different phases of sexual development, i.e., peripuberty, postpuberty and adulthood. Results Body weight and blood glucose levels of pups, on the third postnatal day, were lower in the offspring of diabetic dams compared to controls. Maternal diabetes also provoked delayed testicular descent and preputial separation. In the offspring of diabetic dams the weight of reproductive organs at 40, 60 and 90 days-old was lower, as well as sperm reserves and sperm transit time through the epididymis. However the plasma testosterone levels were not different among experimental groups. Conclusions It is difficult to isolate the effects directly from diabetes and those from IUGR. Although the exposure to hyperglycemic environment during prenatal life and lactation delayed the onset of puberty in male rats, the IUGR, in the studied model, did not influenced the structural organization of the male gonads of the offspring at any point during sexual development. However the decrease in sperm reserves in epididymal cauda and the acceleration in sperm transit time in this portion of epididymis may lead to an impairment of sperm quality and fertility potential in these animals. Additional studies are needed in attempt to investigate the fertility of animals with intrauterine growth restriction by maternal diabetes and

  16. Sexually Dimorphic Gene Expression Associated with Growth and Reproduction of Tongue Sole (Cynoglossus semilaevis) Revealed by Brain Transcriptome Analysis.

    Science.gov (United States)

    Wang, Pingping; Zheng, Min; Liu, Jian; Liu, Yongzhuang; Lu, Jianguo; Sun, Xiaowen

    2016-08-26

    In this study, we performed a comprehensive analysis of the transcriptome of one- and two-year-old male and female brains of Cynoglossus semilaevis by high-throughput Illumina sequencing. A total of 77,066 transcripts, corresponding to 21,475 unigenes, were obtained with a N50 value of 4349 bp. Of these unigenes, 33 genes were found to have significant differential expression and potentially associated with growth, from which 18 genes were down-regulated and 12 genes were up-regulated in two-year-old males, most of these genes had no significant differences in expression among one-year-old males and females and two-year-old females. A similar analysis was conducted to look for genes associated with reproduction; 25 genes were identified, among them, five genes were found to be down regulated and 20 genes up regulated in two-year-old males, again, most of the genes had no significant expression differences among the other three. The performance of up regulated genes in Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis was significantly different between two-year-old males and females. Males had a high gene expression in genetic information processing, while female's highly expressed genes were mainly enriched on organismal systems. Our work identified a set of sex-biased genes potentially associated with growth and reproduction that might be the candidate factors affecting sexual dimorphism of tongue sole, laying the foundation to understand the complex process of sex determination of this economic valuable species.

  17. Sexually Dimorphic Gene Expression Associated with Growth and Reproduction of Tongue Sole (Cynoglossus semilaevis Revealed by Brain Transcriptome Analysis

    Directory of Open Access Journals (Sweden)

    Pingping Wang

    2016-08-01

    Full Text Available In this study, we performed a comprehensive analysis of the transcriptome of one- and two-year-old male and female brains of Cynoglossus semilaevis by high-throughput Illumina sequencing. A total of 77,066 transcripts, corresponding to 21,475 unigenes, were obtained with a N50 value of 4349 bp. Of these unigenes, 33 genes were found to have significant differential expression and potentially associated with growth, from which 18 genes were down-regulated and 12 genes were up-regulated in two-year-old males, most of these genes had no significant differences in expression among one-year-old males and females and two-year-old females. A similar analysis was conducted to look for genes associated with reproduction; 25 genes were identified, among them, five genes were found to be down regulated and 20 genes up regulated in two-year-old males, again, most of the genes had no significant expression differences among the other three. The performance of up regulated genes in Gene Ontology (GO and Kyoto Encyclopedia of Genes and Genomes (KEGG pathway enrichment analysis was significantly different between two-year-old males and females. Males had a high gene expression in genetic information processing, while female’s highly expressed genes were mainly enriched on organismal systems. Our work identified a set of sex-biased genes potentially associated with growth and reproduction that might be the candidate factors affecting sexual dimorphism of tongue sole, laying the foundation to understand the complex process of sex determination of this economic valuable species.

  18. Effect of inactive yeast cell wall on growth performance, survival rate and immune parameters in Pacific White Shrimp (Litopenaeus vannamei

    Directory of Open Access Journals (Sweden)

    Rutchanee Chotikachinda

    2008-10-01

    Full Text Available Effects of dietary inactive yeast cell wall on growth performance, survival rate, and immune parameters in pacific white shrimp (Litopenaeus vannamei was investigated. Three dosages of inactive yeast cell wall (0, 1, and 2 g kg-1 were tested in three replicate groups of juvenile shrimps with an average initial weight of 7.15±0.05 g for four weeks. There was no significant difference in final weight, survival rate, specific growth rate, feed conversion ratio, feed intake, protein efficiency ratio, and apparent net protein utilization of each treatments. However, different levels of inactive yeast cell wall showed an effect on certain immune parameters (p<0.05. Total hemocyte counts, granular hemocyte count, and bacterial clearance were better in shrimp fed diets supplemented with 1 and 2 g kg-1 inactive yeast cell wall as compared with thecontrol group.

  19. Survival and growth of parasitic Maculinea alcon caterpillars (Lepidoptera: Lycaenidae) in nests of three Myrmica ant species

    DEFF Research Database (Denmark)

    Nash, D. R.; Als, Thomas Damm; Boomsma, J. J.

    2011-01-01

    The Alcon blue butterfly (Maculinea alcon) parasitizes the nests of several Myrmica ant species. In Denmark, it uses M. rubra and M. ruginodis, but never M. scabrinodis. To further examine the basis of this specificity and local co-adaptation between host and parasite, the pattern of growth...... and survival of newly-adopted caterpillars of M. alcon in Myrmica subcolonies was examined in the laboratory. M. alcon caterpillars were collected from three populations differing in their host use, and reared in laboratory nests of all three ant species collected from each M. alcon population. While...... there were differences in the pattern of growth of caterpillars from different populations during the first few months after adoption, which depended on host ant species and the site from which the ants were collected, there was no evidence of major differences in final size achieved. Survival was, however...

  20. Effects of sand burial on the survival and growth of two shrubs dominant in different habitats of northern China.

    Science.gov (United States)

    Qu, Hao; Zhao, Ha-Lin; Zhao, Xue-Yong; Zuo, Xiao-An; Wang, Shao-Kun; Chen, Min

    2017-04-01

    Plants that grow in dune ecosystems always suffer from sand burial. Shrubs play implications on the healthy functioning of dune ecosystems due to control blowing sand. However, the survival and growth responses of shrubs to sand burial remain poorly understood. The survival rate and seedling height of two shrubs (Artemisia halodendron and Lespedeza davurica) along with the soil properties under different burial depths were examined in order to reveal the causing ecophysiological attributes of sand burial on shrubs in the desertified region. It was found that A. halodendron can survive a burial depth of 6 cm greater than its seedling height, which is a dominant shrub in mobile dunes with intense burial, whereas a burial depth equivalent to three fourths of its seedling height is detrimental to L. davurica, which is dominant in fixed dunes with less burial. The reasons for the shrub death under sand burial were associated with the physical barrier to vertical growth and the reduction in photosynthetic area. In conclusion, A. halodendron can facilitate the stabilization of mobile dunes because of their high tolerance to the frequent and intensive sand burial, while L. davurica can be beneficial for the recovery process because of their higher survival rates under shallow burial following restoration of mobile dunes.

  1. Eastern Baltic cod : Perspectives from existing data on processes affecting growth and survival of eggs and larvae

    DEFF Research Database (Denmark)

    MacKenzie, Brian; St. John, Michael; Wieland, Kai

    1996-01-01

    exist in our knowledge of processes affecting egg and larval growth and survival, but some promising areas of research are indicated. In particular the seasonality of spawning, deep water oxygen concentrations, predation on eggs, and larval food production require further investigation....... surveys have described food concentrations at appropriate scales for cod larvae, and the species composition of larval diets is unknown. Growth rates for Baltic cod larvae have not been measured and cannot be compared with rates in other areas or to variations in biotic and abiotic factors. Large gaps...

  2. Effects of nisin and temperature on survival, growth, and enterotoxin production characteristics of psychrotrophic Bacillus cereus in beef gravy.

    OpenAIRE

    Beuchat, L R; Clavero, M R; Jaquette, C B

    1997-01-01

    The presence of psychrotrophic enterotoxigenic Bacillus cereus in ready-to-serve meats and meat products that have not been subjected to sterilization treatment is a public health concern. A study was undertaken to determine the survival, growth, and diarrheal enterotoxin production characteristics of four strains of psychrotrophic B. cereus in brain heart infusion (BHI) broth and beef gravy as affected by temperature and supplementation with nisin. A portion of unheated vegetative cells from...

  3. Survival and growth of the giant clam larvae utilizing zooxanthellae from Acropora valenciennesi, Tridacna crocea and Sarcophyton trocheliophorum

    OpenAIRE

    A. Niartiningsih; Magdalena Litaay; Niradhyna W. M

    2015-01-01

    The aim of this study was to know the survival and growth of the giant clam larvae given zooxanthellae from different host. The field experiment was conducted from September ???November 2006 at hatchery of Marine Field Station Barrang Lompo Island, Makassar. Zooxanthellae hosts used were: (A) Table coral (Acropora valenciennesi); (B) Tridacna crocea, (C) soft coral (Sarcophyton trocheliophorum) and (D) control (no additional zooxanthellae). The Complete Randomized Design with four treatments ...

  4. Metastatic triple-negative breast cancer is dependent on SphKs/S1P signaling for growth and survival.

    Science.gov (United States)

    Maiti, Aparna; Takabe, Kazuaki; Hait, Nitai C

    2017-04-01

    About 40,000 American women die from metastatic breast cancer each year despite advancements in treatment. Approximately, 15% of breast cancers are triple-negative for estrogen receptor, progesterone receptor, and HER2. Triple-negative cancer is characterized by more aggressive, harder to treat with conventional approaches and having a greater possibility of recurrence. Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid signaling mediator has emerged as a key regulatory molecule in breast cancer progression. Therefore, we investigated whether cytosolic sphingosine kinase type 1 (SphK1) and nuclear sphingosine kinase type 2 (SphK2), the enzymes that make S1P are critical for growth and PI3K/AKT, ERK-MAP kinase mediated survival signaling of lung metastatic variant LM2-4 breast cancer cells, generated from the parental triple-negative MDA-MB-231 human breast cancer cell line. Similar with previous report, SphKs/S1P signaling is critical for the growth and survival of estrogen receptor positive MCF-7 human breast cancer cells, was used as our study control. MDA-MB-231 did not show a significant effect of SphKs/S1P signaling on AKT, ERK, and p38 pathways. In contrast, LM2-4 cells that gained lung metastatic phenotype from primary MDA-MB-231 cells show a significant effect of SphKs/S1P signaling requirement on cell growth, survival, and cell motility. PF-543, a selective potent inhibitor of SphK1, attenuated epidermal growth factor (EGF)-mediated cell growth and survival signaling through inhibition of AKT, ERK, and p38 MAP kinase pathways mainly in LM2-4 cells but not in parental MDA-MB-231 human breast cancer cells. Moreover, K-145, a selective inhibitor of SphK2, markedly attenuated EGF-mediated cell growth and survival of LM2-4 cells. We believe this study highlights the importance of SphKs/S1P signaling in metastatic triple-negative breast cancers and targeted therapies. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Characterizing the reproduction number of epidemics with early subexponential growth dynamics

    DEFF Research Database (Denmark)

    Chowell, Gerardo; Viboud, Cécile; Simonsen, Lone

    2016-01-01

    in the first few disease generations, before susceptible depletion sets in. In reality, outbreaks can display subexponential (i.e. polynomial) growth in the first few disease generations, owing to clustering in contact patterns, spatial effects, inhomogeneous mixing, reactive behaviour changes or other...... and simulations from mechanistic models, and provide validation against a range of empirical disease datasets. Our results suggest that subexponential growth in the early phase of an epidemic is the rule rather the exception. Mechanistic simulations show that slight modifications to the classical susceptible...

  6. Survival and growth of fish (Lates calcarifer under integrated mangrove-aquaculture and open-aquaculture systems

    Directory of Open Access Journals (Sweden)

    Shanmugaarasu Venkatachalam

    2018-02-01

    Full Text Available The potential use of mangrove swamp for fish farming industry is not clearly known. Therefore, current study was conducted to assess the growth performance of the Asian Seabass, Lates calcarifer cultivated in integrated mangrove-aquaculture system (IMAS and open aquaculture system without mangroves (OAS. Fish survival and biomass production were higher by 11% and 12.5% respectively in the IMAS than those in the OAS. The fish growth performance was higher in monsoon than that in other seasons. It was in association with water quality parameters such as, high levels of DO, chlorophylls-a,b, nitrate-N, DOC, TOC; low levels of light intensity, temperature (air, water, SPM, chlorophyll-c, nitrite-N, ammonia, total phosphate, reactive silicate, and POC; as well with moderate salinity. The water quality seemed to be favourable for growth and survival of the fish. Therefore, integrating the mangroves with fish farming of the Asian seabass is beneficial for better fish survival and biomass production.

  7. GROWTH ENHANCEMENT, SURVIVAL AND DECREASE OF ECTOPARASITIC INFECTIONS IN MASCULINIZED NILE TILAPIA FRY IN A RECIRCULATING AQUACULTURE SYSTEM

    Directory of Open Access Journals (Sweden)

    Isabel Jiménez García

    2012-11-01

    Full Text Available Under lab conditions, tilapia fry at culture densities of 8 fish/L-1 can reach a body weight of 0.5 to 1.0 g after the masculinization phase. In commercial hatcheries, the stocking density is four to six times higher, and consequently the occurrence of ectoparasitic infections also rises. The aim of this study was to examine the growth and survival of masculinized Nile tilapia (Oreochromis niloticus fry in a recirculating aquaculture system (RAS. The fry, which were naturally parasitized by protozoan of the genera Trichodina, Ambiphrya and Chilodonella, weighed 0.013 ± 0.003 g and were reared in replicated tanks (N = 3 during 32 days at density of 18 fish/L-1 in the RAS to maintain good water quality, which was achieved especially during the first 22 days of fish rearing. The infection parameters and growth were monitored twice a week. The final fish weight was 1.17 ± 0. 6 g and survival 99.5%. The most frequent parasites were Trichodina and Gyrodactylus cichlidarum (Monogenea. Although nitrogen compounds increased significantly over the last 10 days of fry rearing, final growth and survival were higher than those reported, additionally, the ectoparasitic infections were relatively low.

  8. Toxicity of mercury (Hg on survival and growth rate, hemato- and histopathological parameters ofOreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Kukuh Nirmala

    2013-11-01

    Full Text Available Heavy metals are serious pollutants of the aquatic environment because of their environmental persistence and ability to be accumulated by aquatic organisms. Oreochromis niloticus exposed to 0, 0.16, 0.5, and 1.0 ppm Hg for 30 days. The aim of this study was to determine the influence of mercury in water on survival rate, growth rates, hematological, and histological parameters of Oreochromis niloticus. This study was conducted from Mei to June 2009. The experimental design was arranged in completely randomized design with four treatments and three replications. Stock density was 8 fish/aquarium with mean initial body weight was 15.70±1.13 g. Growth and survival rates of test fish were decreased with increasing the Hg concentration. Red blood cell (RBC count, haematocrit content, and haemoglobin content decreased when compared to the control. The number of white blood cells (WBC increased in mercuric treated fish. The results are statistically significant at p<0.05 level. Keywords:mercury, survival and growth rate, hematology, histopathology, Oreochromis niloticus

  9. Aster leafhopper survival and reproduction, and Aster yellows transmission under static and fluctuating temperatures, using ddPCR for phytoplasma quantification.

    Science.gov (United States)

    Bahar, Md H; Wist, Tyler J; Bekkaoui, Diana R; Hegedus, Dwayne D; Olivier, Chrystel Y

    2018-01-10

    Aster yellows (AY) is an important disease of Brassica crops and is caused by Candidatus Phytoplasma asteris and transmitted by the insect vector, Aster leafhopper (Macrosteles quadrilineatus). Phytoplasma-infected Aster leafhoppers were incubated at various constant and fluctuating temperatures ranging from 0 to 35 °C with the reproductive host plant barley (Hordium vulgare). At 0 °C, leafhopper adults survived for 18 days, but failed to reproduce, whereas at 35 °C insects died within 18 days, but successfully reproduced before dying. Temperature fluctuation increased thermal tolerance in leafhoppers at 25 °C and increased fecundity of leafhoppers at 5 and 20 °C. Leafhopper adults successfully infected and produced AY-symptoms in canola plants after incubating for 18 days at 0-20 °C on barley, indicating that AY-phytoplasma maintains its virulence in this temperature range. The presence and number of AY-phytoplasma in insects and plants were confirmed by droplet digital PCR (ddPCR) quantification. The number of phytoplasma in leafhoppers increased over time, but did not differ among temperatures. The temperatures associated with a typical crop growing season on the Canadian Prairies will not limit the spread of AY disease by their predominant insect vector. Also, ddPCR quantification is a useful tool for early detection and accurate quantification of phytoplasma in plants and insects.

  10. Homeopathy outperforms antibiotics treatment in juvenile scallop Argopecten ventricosus: effects on growth, survival, and immune response.

    Science.gov (United States)

    Mazón-Suástegui, José Manuel; García-Bernal, Milagro; Saucedo, Pedro Enrique; Campa-Córdova, Ángel; Abasolo-Pacheco, Fernando

    2017-02-01

    Mortality from vibriosis in mollusk production is attributed to pathogenic bacteria, particularly Vibrio alginolyticus. Use of increasingly potent antibiotics has led to bacterial resistance and increased pathogenicity. Alternatives in sanitation, safety, and environmental sustainability are currently under analysis. To-date, homeopathy has been investigated in aquaculture of freshwater fish, but not in marine mollusks. The effect of the homeopathic complexes in the growth, survival, and immune response of the Catarina scallop Argopecten ventricosus were assessed. A bioassay to assess the potential of homeopathy in improving cultivation of juvenile A. ventricosus was conducted for 21 days, with a final challenge of 120 h with V. alginolyticus. The experimental design included two homeopathic formulas The homeopathic complex Passival, consisting of Passiflora incarnata 30 CH, Valeriana officinalis 30 CH, Ignatia amara 30 CH and Zincum valerianicum 30 CH plus Phosphoricum acid 30 CH (treatment TH1) or Silicea terra 30 CH (TH2), two antibiotics (ampicillin = AMP, oxytetracycline = OXY), and two reference treatments (without homeopathic or antibiotic treatment = CTRL, ethanol 30° GL = ETH). Additionally, a negative control CTRL- (untreated/uninfected) is included in the challenge test. Juvenile scallops (4.14 ± 0.06 mm, 13.33 mg wet weight) were cultivated in 4 L tanks provided with aerated, filtered (1 μm), and UV-sterilized seawater that was changed every third day. They were fed a blend of the microalgae Isochrysis galbana and Chaetoceros calcitrans (150,000 cells mL -1 twice a day). All treatments were directly added to the tank water and then 500 mL challenge units were inoculated with 1 × 10 7  CFU/mL (LD 50 ) of V. alginolyticus. Juveniles grew significantly larger and faster in height and weight with TH2 compared to the ETH and CTRL (P homeopathy is a viable treatment for this mollusk to reduce use of antibiotics in scallops and its

  11. Nutritional ecology of the Formosan subterranean termite (Isoptera: Rhinotermitidae): growth and survival of incipient colonies feeding on preferred wood species.

    Science.gov (United States)

    Morales-Ramos, Juan A; Rojas, M Guadalupe

    2003-02-01

    The wood of 11 plant species was evaluated as a food source significantly impacting the growth and survival of incipient colonies of the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae). Colonies of C. formosanus feeding on pecan, Carya illinoensis (Wangenh.), and red gum, Liquidambar styraciflua L., produced significantly more progeny than colonies feeding on other wood species tested. Progeny of colonies feeding on pecan and American ash, Fraxinus americana L., had significantly greater survival than progeny of colonies feeding on other wood species. Colonies feeding on a nutritionally supplemented cellulose based matrix showed similar fitness characteristics as colonies feeding on the best wood treatments. These results indicate that differences observed in colony fitness can be partially explained by nutritional value of the food treatment, raising the possibility that wood from different tree species have different nutritional values to the Formosan subterranean termites. Colonies feeding on loblolly pine, Pinus taeda L., and ponderosa pine, Pinus ponderosa Laws., had significantly lower survival and produced significantly fewer workers and soldiers than colonies feeding on other wood species. Colony survival from 90 to 180 d of age and from 90 to 360 d of age was significantly correlated with the number of workers present at 90 d of colony age, indicating that colony survival depends on the presence of workers. Wood consumption in a multiple-choice study was significantly correlated with colony fitness value. This suggests that feeding preference of C. formosanus is at least partially influenced by the nutritional value of the food source.

  12. The effects of water type on growth, survival and condition of ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-02-01

    Feb 1, 2010 ... Available online at http://www.academicjournals.org/AJB ... Feed conversion ratio did not differ significantly among groups. Survival ... industry holds an important place in the global fishery ... The largest market for aquarium.

  13. Survival and Growth of Northern Red Oak Seedlings Following a Prescribed Burn

    Science.gov (United States)

    Paul S. Johnson

    1974-01-01

    Mortality of northern red oak seedlings in a spring prescribed burn was related to temperature near the root collar. Most of the 42 percent of seedlings that survived the burn developed new shoots from the root collar.

  14. Highly plastic resource allocation to growth and reproduction in females of an African annual fish

    Czech Academy of Sciences Publication Activity Database

    Vrtílek, Milan; Reichard, Martin

    2015-01-01

    Roč. 24, č. 4 (2015), s. 616-628 ISSN 0906-6691 R&D Projects: GA ČR(CZ) GAP506/11/0112 Keywords : Nothobranchius * compensatory growth * egg size * life history * diet restriction Subject RIV: EG - Zoology Impact factor: 2.052, year: 2015

  15. Heterologous production of a ginsenoside saponin (compound K) and its precursors in transgenic tobacco impairs the vegetative and reproductive growth.

    Science.gov (United States)

    Gwak, Yu Shin; Han, Jung Yeon; Adhikari, Prakash Babu; Ahn, Chang Ho; Choi, Yong Eui

    2017-06-01

    Production of compound K (a ginsenoside saponin) and its precursors in transgenic tobacco resulted in stunted growth and seed set failure, which may be caused by strong autotoxicity of heterologously produced phytochemicals against the tobacco itself. Panax ginseng roots contain various saponins (ginsenosides), which are major bioactive compounds. A monoglucosylated saponin, compound K (20-O-(β-D-glucopyranosyl)-20(S)-protopanaxadiol), has high medicinal and cosmetic values but is present in undetectable amounts in naturally grown ginseng roots. The production of compound K (CK) requires complicated deglycosylation of ginsenosides using physicochemical and/or enzymatic degradation. In this work, we report the production of CK in transgenic tobacco by co-overexpressing three genes (PgDDS, CYP716A47 and UGT71A28) isolated from P. ginseng. Introduction and expression of the transgenes in tobacco lines were confirmed by genomic PCR and RT-PCR. All the lines of transgenic tobacco produced CK including its precursors, protopanaxadiol and dammarenediol-II (DD). The concentrations of CK in the leaves ranged from 1.55 to 2.64 µg/g dry weight, depending on the transgenic line. Interestingly, production of CK in tobacco brought stunted plant growth and gave rise to seed set failure. This seed set failure was caused by both long-styled flowers and abnormal pollen development in transgenic tobacco. Both CK and DD treatments highly suppressed in vitro germination and tube growth in wild-type pollens. Based on these results, metabolic engineering for CK production in transgenic tobacco was successfully achieved, but the production of CK and its precursors in tobacco severely affects vegetative and reproductive growth due to the cytotoxicity of phytochemicals that are heterologously produced in transgenic tobacco.

  16. Effect of feeding salt tolerant plants on growth and reproduction of goats

    International Nuclear Information System (INIS)

    Ali, M.; Khanum, S.A.; Naqvi, S.H.M.

    1991-01-01

    Two experiments were conducted to assess the reproductive performance of dwarf goats grazing on salt tolerant and other forages. In Experiment 1, eight female dwarf goats grouped into two treatments of four animals each were allowed to graze either kallar grass only or kallar grass and other salt tolerant forages. The protein content of kallar grass was below the critical level in winter (4.9%) and just above in the summer (8.8%). Its mineral contents were higher than the required level in all seasons. The other salt tolerant forages had higher protein and mineral contents than kallar grass. Animals restricted to kallar grass showed significant loss in liveweight only during winter; the difference between the two groups was not significant in autumn and summer. Conception rate and levels of progesterone and oestradiol 17β were normal in both groups. However, animals restricted to kallar grass only suffered from reduced lactation, abortion and mortality of their kids. In Experiment 2, twenty dwarf goats were allocated to two groups whereby one group had free access to salt tolerant forages and the other to normal forages at different sites. The oestrous cycles of the goats were synchronized by administering two intramuscular injections of 0.5 mL Estrumate 10 days apart. The pattern and concentrations of progesterone were assessed and no difference was observed between the two treatment groups. (author). 20 ref, 5 figs, 3 tabs

  17. Survival significance of epidermal growth factor receptor tyrosine kinase inhibitors and current staging system for survival after recurrence in patients with completely resected lung adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Saji H

    2017-08-01

    Full Text Available Hisashi Saji,1,2 Hiroki Sakai,1 Hiroyuki Kimura,1 Tomoyuki Miyazawa,1 Hideki Marushima,1 Haruhiko Nakamura1 1Department of Chest Surgery, St Marianna University School of Medicine, Miyamae-ku, Kawasaki, Kanagawa, Japan; 2Department of Thoracic Surgery, Tokyo Medical University, Shinjuku-ku, Tokyo, Japan Objective: We previously reported that the staging system and epidermal growth factor receptor (EGFR mutation status are key factors for treatment strategy and predicting survival. However, the significance of these factors as predictors of overall survival (OS and postoperative recurrence survival (PRS has not been sufficiently elucidated. The objective here was to investigate EGFR mutation status and p-stage, which affect PRS and OS in patients with completely resected lung adenocarcinoma, using a different database.Patients and methods: We retrospectively reviewed 56 consecutive lung adenocarcinoma patients with disease recurrence in St. Marianna University Hospital between January 2010 and December 2014.Results: EGFR mutants (M were detected in 16/56 patients (29%. The patients with EGFR M had a better OS than those with EGFR wild-type (WT status (5-year survival: 50.3% vs 43.1, P=0.133. There was no significant difference in the 3-year recurrence-free survival rate between patients with M and WT (6.3% vs 7.7%, P=0.656, and the patients with EGFR M had a significantly better 3-year PRS than those with WT (77.4% vs 51.7%, P=0.033. The 3-year PRS rate for patients with M/pathologic stage (p-stage I–II (87.5% was better than that for patients with M/p-stage III (60.0%, WT/p-stage I–II (52.7%, and WT/p-stage III (43.8%. There was a significant difference between patients with M/p-stage I and WT/p-stage I–II or WT/p-stage III (P=0.021 and 0.030, respectively. During the study period, of the 16 patients with mutants, 12 patients (75% received EGFR-tyrosine kinase inhibitor (TKI therapy and among the 40 patients with WT, no patient received

  18. Phenotype and genetic parameters for body measurements, reproductive traits and gut lenght of Nile tilapia (Oreochromis niloticus) selected for growth in low-input earthen ponds

    NARCIS (Netherlands)

    Charo-Karisa, H.; Bovenhuis, H.; Rezk, M.A.; Ponzoni, R.W.; Arendonk, van J.A.M.; Komen, J.

    2007-01-01

    In this study we present estimates of phenotypic and genetic parameters for body size measurements, reproductive traits, and gut length for Nile tilapia (Oreochromis niloticus) selected for growth in fertilized earthen ponds for two generations. Throughout the experiment, ponds were fertilized daily

  19. Growth and reproduction investment of the young of the year of the squat lobster Munida gregaria (Crustacea: Anomura in the Patagonian coast

    Directory of Open Access Journals (Sweden)

    Martin Varisco

    2015-09-01

    Full Text Available The growth and reproduction investment of the young of the year (0+ of the squat lobster Munida gregaria in San Jorge Gulf, Argentina, were analysed. Moult cycle and size frequency distribution were studied in monthly field samples. Experiments to determine moult increments and intermoult duration were conducted. Sexual maturity, fecundity and reproductive output were analysed in field samples. In addition, maturity experiments in laboratory cultures were conducted. After settlement (November, juveniles showed fast growth until winter (July and growth restarted in September-October. At the beginning of the mating period (early June, males 0+ exhibited mature gonads, whereas females 0+ only showed previtellogenic oocytes. Experimental data showed that females with developed gonads had smaller-size increments in the previous moult. Fecundity and reproductive output were significantly lower in females 0+ than in older females. The early life history of M. gregaria in San Jorge Gulf differs from that of southern populations as those of Beagle Channel and Strait of Magellan due to faster growth and early reproductive investment. Our results suggest that females 0+ of M. gregaria have two investment strategies: early maturity with low fecundity and delayed maturity with higher future fecundity.

  20. Successful reproduction of unmated Tropilaelaps mercedesae and its implication on mite population growth in Apis mellifera colonies

    Science.gov (United States)

    Highly hygienic colonies are known to reduce the reproductive potential of Varroa destructor. For Tropilaelaps mercedesae, information on how bee behavior may influence the mite’s reproductive potential is currently unknown. In this study, we assessed the influence of recapping on the reproduction o...

  1. Growth, mortality and reproduction of the blue tilapia Oreochromis aureus (Perciformes: Cichlidae in the Aguamilpa Reservoir, Mexico

    Directory of Open Access Journals (Sweden)

    Emilio Peña Messina

    2010-12-01

    Full Text Available Tilapia production has increased in Aguamilpa Reservoir, in Nayarit, Mexico, in the last few years and represents a good economic activity for rural communities and the country. We determined growth parameters, mortality and reproductive aspects for 2 413 specimens of blue tilapia Oreochromis aureus in this reservoir. Samples were taken monthly from July 2000 through June 2001, of which 1 371 were males and 1 042 were females. Standard length (SL and total weight (TW were measured in each organism. The SL/TW relationships through power models for sexes were determined. The growth parameters L ∞, k, and t0 of the von Bertalanffy equation were estimated using frequency distribution of length through ELEFAN-I computer program. Finally the reproductive cycle and size of first maturity were established using morph chromatic maturity scale. The results suggested that the males and females had negative allometric growth (bLos parámetros de crecimiento, reproducción y mortalidad de Oreochormis aureus en el embalse de Aguamilpa, México fueron determinados. Un total de 2 413 organismos se recolectaron entre julio de 2000 y junio de 2001, de los cuales 1 371 fueron machos y 1 042 hembras. Se analizó la relación longitud estándar (LE y peso total (PT mediante modelos potenciales. Los parámetros de crecimiento de la ecuación de von Bertalanffy fueron estimados usando la distribución de frecuencia de tallas con ayuda del programa ELEFAN-I. Finalmente se determinó el ciclo reproductivo, talla de primera madurez y fecundidad. Los resultados indicaron que tanto hembras como machos presentaron crecimiento alométrico negativo. Se encontraron diferencias significativas entre hembras y machos para la relación LE- PT sugiriendo modelos separados por sexo. No existieron diferencias significativas en el crecimiento por sexo y la tasa de explotación estimada (0.57/año sugiere que la pesquería durante el periodo de estudio mostró signos de

  2. Growth and reproductive pattern of the caridean shrimp Palaemonetes argentinus (Decapoda:Caridea) in southern Brazil

    OpenAIRE

    Dumont, Luiz Felipe Cestari; D´Incao, Fernando

    2004-01-01

    In crustaceans, due to the absence of permanent hard parts which can be used for age determination, methods on length frequency distribuitions (e.g., Modal progression Analysis - MPA) are commonly employed for ageing. However, the linkage of the coborts followed during a period of time, brings uncertainty to the analysis. The present study suggests inclusion of biological aspects to validate the parameters estimatcd by the von Bertalanffy growth model (VBGM). The population of Palaemonetes ar...