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Histochemistry and histology in planktonic ecophysiological processes determination in a temperate estuary (Mondego River estuary, Portugal)

Pastorinho, M. R.; Antunes, C. P.; Marques, J. C.; Pereira, M. L.; Azeiteiro, U. M. M.; Morgado, F. M.
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Artigo de Revista Científica Formato: aplication/PDF
ENG
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45.96%
Zooplankton communities in temperate climates exhibit well documented seasonal variability. The reasons proposed to explain this kind of behaviour range from the effect of physical-chemical conditions (salinity, nutrients, temperature) growth rates, mortality, migration rates, food availability and predation. It is noticeable that the majority of the factors mentioned are external to the organisms, being environmental factors responsible for time dependent changes in zooplankton abundance. A question may arise from this conclusion, namely, "Could zooplankton blooms, in temperate climates, be mainly modelled by the internal physiological predispositions of the individual organisms?" Or, in a more "functional" formulation, "Could gonads be the baseline regulators of zooplankton abundance?". This study answers this pertinent question, assuming as a basic assumption that the reproductive potential of these organisms is constant, being controlled by extrinsic factors. For this purpose, histological and histochemical techniques were applied to the mysid Mesopodopsis slabberi, a key species in the Mondego River estuary, in order to establish a scale of gonadic development that would allow comparisons between high and low density periods. Histology reveals itself as the ideal base to establish a tool for the evaluation of the gonadic masses by allowing to calculate oocyte dimensions (trough biometry) and determine its maturity status through calculation of the N/C ratio and histochemical analysis (PAS and Tetrazonium reaction for proteins). Upon creation...

Biologia reprodutiva do caranguejo simbionte Pachycheles monilifer (Crustacea, Decapoda, Anomura): relação entre potencial reprodutivo e substrato; Reproductive biology of the symbiotic crab Pachycheles monilifer (Crustacea, Decapoda, Anomura): relation between reproductive potential and substrate

Leone, Isabela Carnielli
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 27/05/2013 PT
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56.06%
Os crustáceos estão entre os invertebrados marinhos mais diversos e tendem a se associar com outros organismos a fim de encontrar abrigo, oferta de alimento e um lugar seguro para reprodução. Aspectos reprodutivos como fecundidade, tamanho dos embriões e energia investida na reprodução são os principais parâmetros para a compreensão da história natural de uma espécie e/ou população. Assim, esse trabalho foi desenvolvido no sentido de investigar tais parâmetros e a influência do tipo de substrato ocupado. A espécie utilizada como modelo de estudo foi o caranguejo porcelanídeo Pachycheles monilifer coletado em dois substratos biológicos diferentes, no briozoário Schizoporella errata no píer do Itaguá e no poliqueto Phragmatopoma caudata na praia Grande, ambas as paias localizadas em Ubatuba, litoral norte de SP. Somente os embriões em estágio inicial de desenvolvimento foram utilizados para os cálculos de fecundidade e investimento reprodutivo (RO). Os embriões foram contados e medidos sob esteromicroscópio. Para obtenção do RO foram utilizados os pesos secos das fêmeas ovígeras e das massas de embriões, previamente secos em estufa. Além dos aspectos reprodutivos, análises de distância genética também foram realizadas pelo sequenciamento de genes mitocôndrias (16S e COI) de exemplares de P. monilifer. A estimativa da porcentagem de variação genética intra e interespecífica...

The effects of constant and alternating temperatures on the reproductive potential, life span, and life expectancy of Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae)

Cardoso, Valesca Veiga; Ferreira, Melissa Prietto; Montagner, Juliana de Moura; Garcia Fernandez, Casimiro; Moreira, Jose Claudio Fonseca; Oliveira, Alice Kalisz de
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
Relevância na Pesquisa
65.96%
O desenvolvimento ovariano, ovoposição, eclosão larval, atividade de ornitina descarboxilase (ODC), medidas de largura, comprimento e área do ovário, testículo e apódema ejaculatório e número de espermatozóides de Anastrepha fraterculus (Wiedemann) foram analisados em temperaturas alternadas (20º/6oC e 20º/13oC) e constantes (6oC e 25oC). A longevidade e a expectativa de vida também foram analisadas em ambos os sexos. Todos os resultados sugerem que a temperatura baixa e principalmente as temperaturas alternadas afetam não somente o potencial reprodutivo de machos e fêmeas, mas também sua longevidade e expectativa de vida, prolongando-as. Essas mudanças podem ser uma poderosa estratégia usada por A. fraterculus para sobreviver às condições estressantes de temperatura observadas no inverno na região produtora de maçãs, tornando-as capazes de aumentar sua densidade populacional e causar dano à maçã no início da primavera.; Ovarian development, oviposition, larval eclosion, ornithine decarboxylase (ODC) activity, ovarian, testis and ejaculatory apodeme measurements (length, width, and area), and the number of spermatozoa of Anastrepha fraterculus (Wiedemann) were analyzed at alternating (20º/6ºC and 20º/13oC) and constant (6oC; 25oC) temperatures. Life span and life expectancy were also analyzed for both genders. All the results suggest that temperature...

Efeito de sinigrina aplicada em folhas de brássicas sobre características biológicos de Plutella xylostella (L.) (Lepidoptera: Plutellidae)

Carvalho, Jackeline da Silva; Bortoli, Sergio Antonio de; Thuler, Robson Thomaz; Goulart, Roberto Marchi; Volpe, Haroldo Xavier Linhares
Fonte: Editora da Universidade Estadual de Maringá (EDUEM) Publicador: Editora da Universidade Estadual de Maringá (EDUEM)
Tipo: Artigo de Revista Científica Formato: 15-20
POR
Relevância na Pesquisa
45.96%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); O objetivo deste trabalho foi avaliar o efeito da ingestão de sinigrina aplicada em folhas de couve e brócolis sobre algumas características biológicas de Plutella xylostella. Foram utilizadas duas cultivares de brássicas: couve-manteiga da Geórgia e brócolis Ramoso Piracicaba Precoce, sendo elas tratadas com soluções de sinigrina a 0,2; 0,4; 0,8; 1,6 e 3,2 mg mL-1, contendo 5% de Tween20®, e uma testemunha, apenas com solução de Tween20®. Avaliou-se a duração e viabilidade das fases larval e pupal, peso de pupas, longevidade e razão sexual dos adultos, fecundidade das fêmeas, período de incubação e viabilidade da fase de ovo, tendo-se calculado o potencial reprodutivo corrigido (PRC). As médias foram avaliadas pela análise multivariada de agrupamento e de componentes principais. O maior potencial reprodutivo foi apresentado pela dose de 0,2 mg mL-1 em couve. As análises multivariadas proporcionaram melhor discriminação dos tratamentos em relação à menor concentração testada. Concluiu-se que baixa concentração de sinigrina...

Differential occupation of habitat as a reproductive strategy of the blue crab Callinectes ornatus Ordway, 1968 (Crustacea: Decapoda)

de Andrade, Luciana Segura; Bertini, Giovana; Fransozo, Vivian; Teixeira, Gustavo Monteiro; de Paiva Barros-Alves, Samara; Fransozo, Adilson
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 1-10
ENG
Relevância na Pesquisa
46.07%
The reproductive biology of a species includes factors beyond its sexual maturity, fecundity and reproductive period, and may extend to the differential distribution of individuals. The reproductive dynamics of the blue crab Callinectes ornatus was investigated through monthly collections over the course of 2 years in three bays on the southeastern coast of Brazil. For each bay, six transects were established, four of them parallel to the beach line (at depths of 5, 10, 15, and 20 m), one transect exposed to wave action, and another sheltered from waves. Females and males were classified according to the gonadal maturation stage, and were grouped as individuals with reproductive potential (mature gonads or breeding females) or not (rudimentary gonads or in development). Analyses using ordination techniques (PCA) and gradient analysis (CCA) showed that 82.13 % of environmental variations were explained by the transect arrangement, and these characteristics explained 86.70 % of the differential distribution of female crabs and 96.57 % of the distribution of males. These results indicate that females with reproductive potential were more abundant in deeper regions, while females with rudimentary or developed gonads were abundant in shallower habitats and areas sheltered from wave action. Thus...

Plutella xylostella (Linnaeus, 1758) (Lepidoptera: Plutellidae): efeito da sinigrina aplicada em folhas de couve e brócolis

Carvalho, Jackeline da Silva
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: ix, 57 f. : il.
POR
Relevância na Pesquisa
45.92%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Pós-graduação em Agronomia (Entomologia Agrícola) - FCAV; O trabalho foi desenvolvido no Laboratório de Biologia e Criação de Insetos (LBCI) da Faculdade de Ciências Agrárias e Veterinárias, Unesp – Jaboticabal, SP, para estudar os efeitos de diferentes concentrações de sinigrina aplicada na superfície foliar de couve e brócolis, em alguns parâmetros biológicos de Plutella xylostella. Para realização dos testes, sinigrina foi aplicada à parte ventral/dorsal das folhas de brássicas das cultivares ‘Da Geórgia’ (couve-manteiga) e ‘Ramoso Piracicaba Precoce’ (brócolis), em solução 5% de Tween 20® em diferentes concentrações (0,0; 0,2; 0,4; 0,8; 1,6 e 3,2 mg/mL). Assim como, avaliou-se o consumo, pelas lagartas, através de medidas de peso fresco, peso seco, área foliar e escala visual de notas para os danos. Observou-se que concentração baixa de sinigrina, em couve e em brócolis, não prejudicou o desenvolvimento de P. xylostella, porém altas concentrações afetaram o parâmetro viabilidade. A análise de agrupamentos, pelo método de “cluster”, mostrou que a dose 0,2mg/mL de sinigrina em ambas variedades apresentou os maiores contrastes...

Collection of field reproductive data from carcasses of the female Eurasian lynx (Lynx lynx).

Axnér, E.; Payan-Carreira, R; Setterlind, P; Asbrink, J; Söderberg, A
Fonte: Universidade de Trás-os-Montes e Alto Douro Publicador: Universidade de Trás-os-Montes e Alto Douro
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46%
Information about reproductive physiology in the Eurasian lynx (Lynx lynx) would generate knowledge that could be useful in the management of the Swedish lynx population based on the knowledge about their reproductive potential and population development. Age-related differences in ovulation and implantation rates would affect the reproductive output and the development of the population. The aims of this study were to evaluate a protocol for collection of reproductive data from carcasses by comparisons with published field data and to generate data about reproduction in the Swedish lynx. Reproductive organs from 120 females that were harvested between March 1 and April 9 from 2009 to 2011 were collected and evaluated macroscopically for placental scars. Females had their first estrus as yearlings but did not have their first litter until the next season. Pregnancy rates were lower in 2-year-old females than in females aged 3 to 7 years but did not differ significantly from females aged 8 to 13 years (54.5%, 95.6%, and 75.0%, respectively). CL from the present season were morphologically distinctly different from luteal bodies from previous cycles (LBPC). All females ≥3 years had macroscopically visible LBPC, whereas only 67% of 22 to 23 months old females had one to three LBPC and no females <1 year of age had LBPC. Females aged 34 to 35 months had up to eight LPBC...

Comparison of the reproductive behavior between isolated Peckia chrysostoma (Wiedemann, 1830) and Adiscochaeta ingens (Walker, 1849) (Diptera: Sarcophagidae) females reared in laboratory

Ferraz,Marisa Vianna
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/1992 EN
Relevância na Pesquisa
45.97%
In both species, maintained under laboratory environmental conditions, anautogeny was comproved and all females that had free access to proteic source were fertiles. We obtained the following average values for Peckiachrysostoma: 59.7 ± 15.6 and 81.8 ± 15.4 days of longevity in the respective cases of free access and no access to proteic source, 21.4 ± 4.3 days of pre-larviposition period and 35.2 ± 16.5 days of larviposition period, 5.3 ± 1.8 larvipositions female with 7.0 ± 1.1 days of periodicity, 35.7 ± 6.1 larvae per larviposition leading to a total number of 183.8 ± 69.2 viable larvae per female and 94.8% ± 5.3% of productivity. The mean number of ovarioles per female was 56.4 ± 9.8, resulting in a reproductive potential of 63.3%. For Adiscochaeta ingens, the obtained average values were: 41.3 ± 6.3 and 52 ± 13.1 days of longevity in the respective cases of free access and no access to proteic source, 15.3 ± 1.7 days of pre-larviposition period and 21.5 ± 7.5 days of larviposition period, 3 ± 0.7 larvipositions per female with 10.4 ± 0.8 days of periodicity, 30.3 ± 8.2 larvae per larviposition leading to a total number of 78.5 ± 21.7 viable larvae per female and 90.1% ± 16% of productivity. The mean number of ovarioles per female was 54.6 ± 5.2...

The Effects of a DNA Virus Infection on the Reproductive Potential of Female Tsetse Flies, Glossina morsitans centralis and Glossina morsitans morsitans (Diptera: Glossinidae)

Sang,Rosemary C; Jura,Walter GZO; Otieno,Leonard H; Mwangi,Richard W
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/1998 EN
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55.92%
Reproductive anomalies associated with the tsetse DNA virus infection in the female tsetse hosts, Glossina morsitans centralis Machado and Glossina morsitans morsitans Westwood, inoculated with the virus during the 3rd instar larval stage were studied and the data compared to those obtained from the control females injected with sterile physiological saline. Virus infected flies had significantly longer first and second pregnancy cycles (P<0.0001) and produced pupae that were of significantly less weight in milligrams (P<0.0001) compared to controls. Transmission of the virus to progeny was not absolute and only 21% of G. m. centralis and 48% of G. m. morsitans first progeny flies from infected females developed salivary gland hypertrophy as a result of transmission from mother to progeny. The virus infected females produced significantly fewere pupae compared to the controls during the experimental period (P<0.00001).

The effects of constant and alternating temperatures on the reproductive potential, life span, and life expectancy of Anastrepha fraterculus (Wiedemann) (Dipteria: Tephritidae)

CARDOSO,V. V.; FERREIRA,M. P.; MONTAGNER,J. M.; FERNANDEZ,C. G.; MOREIRA,J. C.; OLIVEIRA,A. K.
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2002 EN
Relevância na Pesquisa
65.96%
Ovarian development, oviposition, larval eclosion, ornithine decarboxylase (ODC) activity, ovarian, testis and ejaculatory apodeme measurements (length, width, and area), and the number of spermatozoa of Anastrepha fraterculus (Wiedemann) were analyzed at alternating (20º/6ºC and 20º/13°C) and constant (6°C; 25°C) temperatures. Life span and life expectancy were also analyzed for both genders. All the results suggest that temperature, especially alternating temperatures, increase not only male and female reproductive potential but also their life span and life expectancy. These changes can be a powerful strategy triggered by A. fraterculus as a means to survive the stressful temperature conditions found in winter in the apple production region in Brazil, enabling this species to increase its population density and cause apple damage when spring begins.

Population dynamics and reproductive biology of Achatina fulica Bowdich, 1822 (Mollusca, Gastropoda) in Salvador - Bahia

Silva,Eder Carvalho da; Omena,Elianne Pessoa
Fonte: Instituto Virtual da Biodiversidade | BIOTA - FAPESP Publicador: Instituto Virtual da Biodiversidade | BIOTA - FAPESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2014 EN
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46.03%
The risks following introduction of invasive species are enormous and incalculable. Achatina fulica is considered one of the 100 species of greatest invasive potential, stands out among the land pulmonate snails, mostly for its high reproductive potential that accelerates the process of dispersion, increasing the damages related to health (disease transmission), to economy (crops destruction) and to environment (biodiversity loss). In order to investigate the relationship of the African snail with the environment, trying to relate sexual activity with climatic variables (temperature, rainfall and humidity), a study was conducted on aspects of population dynamics and reproductive biology in Salvador city. The snails were collected by hand, monthly. Morphometric data were obtained in the field and dissections to analyze the reproductive system at laboratory. To test if there was a greater sexual activity in wet periods was performed first a Principal Component Analysis (PCA) with climatic variables, followed by a regression between precipitation (the most influential environmental variable) and the variable of interest (sexual activity). The results showed that there is an apparent annual cycle for A. fulica, with a recruitment period covering the end of rainy season and the dry season (August to December 2006 and February 2007). Increase of shell size (height) and of sexual activity were observed during the rainy season...

The Effects of Female Shell Size on Reproductive Potential of the Egg Capsule in Rapa Whelk Rapana venosa in Three Regions of Different Salinities

Chung, Ee-Yung; Park, Kwan Ha; Lee, Chang-Hoon; Park, Young Jae
Fonte: Korean Society of Developmental Biology Publicador: Korean Society of Developmental Biology
Tipo: Artigo de Revista Científica
Publicado em /03/2013 EN
Relevância na Pesquisa
45.96%
We investigated the effects of shell height on reproductive potential of the female Rapana venosa in three regions of different salinities (the coastal zone of the Gwangyang Bay (S-1); the upper reaches (S-3); lower reaches (S-2) of the Seomjin River). The number of egg capsules, egg capsule height, and fecundity associated with reproductive potential of larger female rapa whelks were higher than those of smaller individuals in all three regions. Correlation analyses showed that there is a significant positive correlation between egg capsule and female shell height. Mean of shell heights, egg capsule heights, the number of egg capsules in an egg mass, and fecundity in an egg capsule produced from female individuals inhabiting S-1 region were markedly higher than those inhabiting S-2 and S-3 regions. In particular, the fecundity of the rapa whelk increased with the salinity and shell height. Although large rapa whelks produced a large number of egg capsules at S-1 region, those at S-3 habitat laid less egg capsules with smaller size. If these rapa whelks were put into S-2 region, the number of egg capsules produced by a female at S-2 region was slightly larger than those produced by a female at S-3 region. This provides a clear evidence that the number of the egg capsules can be controlled by the salinity. In the coastal zone of the Gwangyang Bay and the upper reaches of Seomjin River...

Fishery Induces Sperm Depletion and Reduction in Male Reproductive Potential for Crab Species under Male-Biased Harvest Strategy

Pardo, Luis Miguel; Rosas, Yenifer; Fuentes, Juan Pablo; Riveros, Marcela Paz; Chaparro, Oscar Roberto
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 13/03/2015 EN
Relevância na Pesquisa
46.01%
Sperm depletion in males can occur when polygynous species are intensively exploited under a male-biased management strategy. In fisheries involving crabs species, the effects of this type of management on the reproductive potential is far from being understood. This study tests whether male-biased management of the principal Chilean crab fishery is able to affect the potential capacity of Metacarcinus edwardsii males to transfer sperm to females. Five localities in southern Chile, recording contrasting crab fishery landing, were selected to assess the potential of sperm depletion triggered by fishery. Seasonally, male crabs from each locality were obtained. Dry weight and histological condition of vasa deferentia and the Vaso-Somatic Index (VSI) were determined in order to use them as proxies for sperm depletion and male reproductive condition. A manipulative experiment was performed in the laboratory to estimate vasa deferentia weight and VSI from just-mated males in order to obtain a reference point for the potential effects of the fishery on sperm reserves. Sperm storage capacity is significantly affected by fisheries; during the mating season vasa deferentia from localities with low fishery intensity were heavier than those from high intensity fisheries...

Inheritance of Traits Associated with Reproductive Potential in Apis mellifera capensis and Apis mellifera scutellata Workers

Jordan, Lyndon A.; Allsopp, Michael H.; Beekman, Madeleine; Wossler, Theresa C.; Oldroyd, Benjamin P.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
Relevância na Pesquisa
45.96%
When workers of the thelytokous Cape honeybee, Apis mellifera capensis, come into contact with colonies of the neighboring arrhenotokous subspecies Apis mellifera scutellata, they can become lethal social parasites. We examined the inheritance of 3 traits (number of ovarioles, number of basitarsal hairs, and size of spermatheca) that are thought to be associated with reproductive potential in A. m. capensis workers. To do so, we produced hybrid A. m. scutellata/A. m. capensis queens and backcrossed them to either A. m. capensis or A. m. scutellata drones. We then measured the 3 traits in parental, hybrid, and backcross offspring. We show that the 3 traits are phenotypically correlated. We also show that the expression of ovariole number, basitarsal hairs, and size of spermatheca is influenced by the genotype of the individual and the rearing environment but that the influence of the rearing environment is less important to the number of ovarioles. We hypothesize a single recessive allele (l), present at high frequency in natural A. m. capensis populations, which when homozygous causes larvae to elicit more food. This increased feeding as larvae causes resulting adult workers to develop more queen-like morphology and increased reproductive potential. The number of ovarioles...

Reproductive Potential, Sex Ratio, and Mating Efficiency of the Straw Itch Mite (Acari: Pyemotidae)

Bruce, William A.; Wrensch, Dana L.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
Relevância na Pesquisa
46.04%
Pyemotid mites are common parasites of many species of Lepidoptera, Coleoptera, and Hymenoptera. They have been associated incidentally with virtually every insect order, paralyzing and ultimately killing their hosts. The straw itch mite, Pyemotes tritici (Lagrèze-Fossat and Montané 1851), has been studied the most in this family. The feasibility of using P. tritici females in mass-rearing projects related to biological control programs (e.g., stored-product insects) depends on fundamental knowledge of their reproductive and population biology. P. tritici reproduces by arrhenotokous parthenogenesis and sex ratio is extremely female biased. Females become physogastric as they feed on host hemolymph. Offspring development is ovoviviparous: diploid adult females and haploid adult males emerge from a birth canal on the opisthosoma. Two studies were designed to assess female and male reproductive potential (progeny number and sex ratio), emergence rates, and male mating ability. The first study measured daily and total progeny number and sex ratio from 128 isolated gravid females. Results indicated that females produced up to 355 offspring, averaging 254 total progeny of which only 8.7% were male. Males emerged faster than females and >50% of all progeny emerged in the first 6 days. The mean duration of progeny emergence was 15.3 d. In the second study...

Report of the Workshop on Implementation of Stock Reproductive Potential into Assessment and Management Advice for Harvested Marine Species

MORGAN M. J.; MARSHALL C. Tara; O’BRIEN L.; MOSQUEIRA SANCHEZ IAGO; CERVIÑO Santiago
Fonte: NORTHWEST ATLANTIC FISHERIES ORGANIZATION Publicador: NORTHWEST ATLANTIC FISHERIES ORGANIZATION
Tipo: Articles in periodicals and books Formato: Online
ENG
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45.96%
A workshop on Implementation of Stock Reproductive Potential into Assessment and Management Advice for Harvested Marine Species that was held at the University of Aberdeen, Scotland on April 12–14, 2011. This Workshop was a key deliverable for the NAFO WG on Reproductive Potential. This workshop was held in conjunction with the EU COST Action Fish Reproduction and Fisheries (FRESH).; JRC.G.4-Maritime affairs

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

Davis, Clinton J.; Ruhmann, Emma K.; Acharya, Kumud; Chandra, Sudeep; Jerde, Christopher L.
Fonte: PeerJ Inc. Publicador: PeerJ Inc.
Tipo: Artigo de Revista Científica
Publicado em 03/11/2015 EN
Relevância na Pesquisa
45.99%
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 <170 days at 9 ppm and 12 ppm...

Aging and reproductive potential in women.

Fitzgerald, C.; Zimon, A. E.; Jones, E. E.
Fonte: Yale Journal of Biology and Medicine Publicador: Yale Journal of Biology and Medicine
Tipo: Artigo de Revista Científica
Publicado em //1998 EN
Relevância na Pesquisa
46%
Reproductive potential in women declines with age. Age-related changes in the ovary account for most of this loss of reproductive function. Oocytes, all of which are present at birth, decline in number and quality with age. The endocrine function of the ovary also declines with age, and the ovary becomes unable to sustain its normal function in the neuroendocrine axis. The neuroendocrine axis may be further affected by primary changes occurring in the hypothalamus and pituitary during aging, although this has not been established in humans. Aging also affects the function of the uterus as the endometrium loses its ability to support implantation and growth of an embryo. Diminished uterine function during aging may be due to changes in the uterine vasculature or to changes in the hormone-dependent development of the endometrium. Finally, aging increases a woman's risk of developing medical, gynecologic or obstetric conditions that may impair her fertility. Knowledge of these affects of aging on a woman's reproductive function is essential to advise and treat the growing number of women seeking pregnancy at advanced reproductive age.

Reproductive potential predicts longevity of female Mediterranean fruitflies.

Müller, H. G.; Carey, J. R.; Wu, D.; Liedo, P.; Vaupel, J. W.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 07/03/2001 EN
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46.01%
Reproduction exacts a price in terms of decreased survival. Our analysis of the interplay between age patterns of fecundity and mortality for individual female medflies (Ceratitis capitata) revealed that individual mortality is associated with the time-dynamics of the egg-laying trajectory. In a sample of 531 medflies, we found that each individual has a characteristic rate of decline in egg laying with age. This defines an individual's rate of reproductive exhaustion. This rate was shown to predict subsequent mortality The larger the remaining reproductive potential, the lower the subsequent mortality An increased mortality risk was seen in flies for which egg production declined rapidly early on, irrespective of the level of egg production. Thus, reproductive potential and lifetime are coupled in such a way that those flies which are able to profit most from an extended life span in terms of increased egg output are indeed likely to live longer.

Survival and reproductive potential of different cohorts of Calomys venustus

Gomez,María D.; Provensal,María C.; Polop,Jaime J.
Fonte: Mastozoología neotropical Publicador: Mastozoología neotropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2007 EN
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In order to determine winter survival and reproductive potential in cohort 2 (C2) and cohort 3 (C3) of Calomys venustus we compared these parameters between individuals of these cohorts and their offspring. Forty six males (13 C2 and 33 C3) and 29 females (21 C2 and 8 C3) were observed from June to September to determine winter survival. There were no significant differences in male and female survival between cohorts. Twenty three male-female pairs of C2 and 14 of C3 were placed in different shelters from October to January to determine the reproductive potential, which was measured as litter size, number of litters, post-partum pregnacies utilization, offspring survival and growth at weaning. There were not any significant differences in the considered reproductive parameters between the two cohorts, except for post-partum pregnancies. C2 and C3 individuals as overwintering cohort would not contribute differently to cohort 1 abundance.