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Endocrine signatures underlying plasticity in postembryonic development of a lower termite, Cryptotermes secundus (Kalotermitidae)

KORB, Judith; HOFFMANN, Katharina; HARTFELDER, Klaus
Fonte: WILEY-BLACKWELL PUBLISHING, INC Publicador: WILEY-BLACKWELL PUBLISHING, INC
Tipo: Artigo de Revista Científica
ENG
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Wood-dwelling termites are characterized by an extremely high and unique developmental flexibility that allows workers, which are immatures, to explore all caste options. The endocrine signatures underlying this flexibility are only vaguely understood. We determined juvenile hormone (JH) and ecdysteroid hemolymph titers during postembryonic development and in terminal instars of the drywood termite Cryptotermes secundus using field and laboratory colonies. Postembryonic development is characterized by a drop in JH titers at the transition from larval (individuals without wing buds) to nymphal (individuals with wing buds) instars. JH titers were low in winged sexuals and reproducing primary reproductives (< 200 pg/mu l) but were by an order of magnitude higher in neotenic replacement reproductives. The unique regressive molts of termites seem to be characterized by elevated JH titers, compared with progressive or stationary molts. Ecdysteroid titers were generally low in nymphal instars and in primary reproductives (< 50 pg/mu l). It was only during the third and fourth nymphal instars and in winged sexuals where some individuals showed elevated ecdysteroid titers. These results are the most comprehensive endocrinological data set available for any lower termite...

Influência da quantidade de recursos alimentares e da sazonalidade sobre a produção de sexuados em Scaptotrigona aff. depilis (Apidae, Meliponini); Influence of the amount of food resources and seasonality on the production of sexual offspring in Scaptotrigona aff. depilis (Apidae, Meliponini)

Koffler, Sheina
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 18/06/2013 PT
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Em colônias de insetos eussociais, é prevista uma demanda conflitante entre a produção de operárias e indivíduos reprodutivos, visto que operárias realizam tarefas essenciais para a sobrevivência da colônia, enquanto machos e rainhas estão relacionados com a reprodução. Nesse trabalho, foram testadas as hipóteses (1) que a produção de sexuados estaria diretamente relacionada com a disponibilidade de recursos alimentares e (2) que haveria uma regulação temporal da produção de sexuados, com épocas mais favoráveis à produção de reprodutivos (verão) e menos favoráveis (inverno). O sistema de estudo foi a abelha sem ferrão Scaptotrigona aff. depilis e foram realizados dois experimentos. No primeiro experimento, na estação de verão, foram montadas quinze colônias padronizadas e sorteadas em cinco grupos experimentais. Os grupos A2 e C2 receberam o dobro de alimentação artificial (xarope de açúcar e pólen apícola) do que os grupos A1 e C1. As colônias dos grupos C2 e C1 foram mantidas confinadas, enquanto as colônias dos grupos A2 e A1 podiam forragear livremente. O grupo A0 (controle) não recebeu alimentação artificial e as colônias permaneceram abertas. No inverno, o mesmo experimento foi realizado...

Estimativa do potencial de rendimento por estrato do dossel da soja, em diferentes arranjos de plantas; Yield potential estimated by soybean canopy stratum in response to plant arrangement

Rambo, Lisandro; Costa, Jose Antonio; Pires, Joao Leonardo Fernandes; Parcianello, Geovano; Ferreira, Felipe Gutheil
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
POR
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O potencial de rendimento da soja pode ser modificado pelo arranjo de plantas. Esta alteração pode resultar da contribuição diferenciada dos estratos do dossel para a determinação do potencial. O experimento foi conduzido na Estação Experimental Agronômica da UFRGS, em Eldorado do Sul, RS, na estação de crescimento 2000/01, objetivando avaliar o potencial de rendimento em três estratos do dossel da soja em função da modificação do arranjo de plantas, em dois regimes hídricos. Utilizou-se a cultivar ‘BRS 137’, em semeadura direta. Os tratamentos constaram de níveis de irrigação (irrigado e não irrigado); espaçamentos entre linhas (20 e 40cm), e populações de plantas (20, 30 e 40 plantas m-2). Estimou-se o potencial de rendimento no início do enchimento de grãos (R5), admitindo-se que todas as flores se transformassem em legumes e que todos os legumes presentes neste estádio atingissem a maturação, formando grãos e contribuindo para o rendimento. O dossel foi divido em três estratos, por dois planos paralelos ao solo, determinando-se o potencial de rendimento e o rendimento de grãos nas três seções do dossel. O tratamento irrigado apresentou maior potencial de rendimento da planta inteira em R5 (14976kg ha-1) e rendimento de grãos em R8 (maturação) que o não irrigado (12148kg ha-1)...

Mandibular glands in reproductives of asian termite coptotermes gestroi (Isoptera: Rhinotermitidae)

Costa-Leonardo, A. M.; Goncalves, F. C.; Laranjo, L. T.
Fonte: Comite Interamericano Soc Microscopia Electronica-ciasem Publicador: Comite Interamericano Soc Microscopia Electronica-ciasem
Tipo: Artigo de Revista Científica Formato: 220-231
ENG
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); This study reports on the morphology of the mandibular glands in reproductives of Coptotermes gestroi, including foraging nymphs and queens of different ages. These exocrine glands are very small and located between the mandibles and maxillae. The mandibular glands are composed of two types of cells: class 3 secretory cells and small canal cells and are characterized by the presence of the end apparatus that is a structure responsible for the junction between the secretory cell and its canal cell. The end apparatus is formed by the receiving canal that has an inner interrupted cuticle and is surrounded by microvilli. The variation in the histology of these glands among the different reproductives was associated with the presence of extracellular spaces which function as secretion reservoirs. Older primary reproductives showed more dilated extracellular spaces inside of the glands in relation to younger and alate reproductives. The ultrastructure of secretory cells showed different types of secretion. Electron-lucid secretions were present in female alates (virgin queens) and small lipid droplets and large myeloid granules in 3-year-old queens. The enlarged extracellular spaces present in the histological sections of class 3 cells correspond to the reservoirs or regions full of secretion observed in the cell ultrastructure. The occurrence of different types of secretions in the mandibular glands among female reproductives of C. gestroi is in accordance with distinct glandular functions in different phases of the life of these individuals.

Morphology of the nymphoid replacement reproductives in the neotropical termite Armitermes euamignathus (Isoptera, Termitidae, Nasutitermitinae)

Costa-Leonardo, A. M.; Barsotti, R. C.; Soares, H. X.
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 131-141
ENG
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Numerous nymphoid reproductives were found in three field nests of Armitermes euamignathus collected in Brazil. We report here a morphological description and a biometric study of these individuals. Nymphoid replacements displayed narrow wing buds when compared with those present in nymphs from the three last instars. Thorax morphology of the nymphoids was similar to the penultimate nymphal instar (N4) or to the ultimate nymphal instar (N5), and their origin from these instars of nymphs is discussed. All the nymphoids had eyes, ocelli, and 15 antennal segments. The nymphoid females from nest 1 had different grades of physogastry and royal fat body. The nymphoid females from nests 2 and 3, the nymphoid males from all nests, and the primary king from nests 2 acid 3 had a common fat body, which is similar to that present in alates. The ovaries and the testes of nymphoids were fully mature and the corpora allata larger than those in imagoes. The mandibular glands were also enlarged in nymphoids but the tergal glands were absent. (C) 1999 Wiley-Liss, Inc.

Multiple nymphoid reproductives in the nests of the neotropical termite, Armitermes euamignathus (Isoptera, Termitidae, Nasutitermitinae)

Costa-Leonardo, Ana Maria; Barsotti, Raquel Cristina; Soares, Helena Xavier
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 197-205
ENG
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Armitermes euamignathus Silvestri (Termitidae, Nasutitermitinae) is a mound building termite that is common in Brazilian regions of the Cerrado vegetation. Multiple neotenic reproductives were found in three isolated nests of these species localized in other secondary habitats different from Cerrado vegetation. The number of second form queens was always higher than the number of secondary males. In two of these nests, the primary king was present along with the second form reproductives. Eggs and brood were found in the three nests but mature alates were present in only one. Multiple neotenic reproductives were never found in the studied Cerrado region where the nests contained only the primary pair. A study of oviposition rate between primary queens and nymphoid reproductives showed an increased number of eggs in the colony headed by neotenic reproductives.

Response to orphaning in two Neotropical termites: Armitermes euamignathus and Embiratermes festivellus

Costa-Leonardo, Ana Maria; Soares, Helena Xavier; Barsotti, Raquel Cristina
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 109-114
ENG
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In this paper we examine the potential of the termites Armitermes euamignathus Silvestri: 1901 and Embiratermes festivellus (Silvestri, 1901) (Isoptera, Termitidae, Nasutitermitinae) to produce neotenics experimentally. Three nests of the mound-building termite A. euamignathus, from the Brazilian cerrado, had their primary queens removed in August 1994. After 12 months, only one mound survived; it had a normal appearance. In this healthy, orphaned colony we found the primary king, six physogastric nymphoid female replacement reproductives, two ergatoid female replacement reproductives, 46 nymphs, several presoldiers, soldiers, workers, larvae and many eggs. These data show that neotenics in A. euamignathus may originate from both workers and nymphs, but nymphoids are produced in larger numbers. The biometric study of nymphs and nymphoids suggests that these brachypterous neotenics were derived from third instar nymphs after a single moult or from four instar nymphs after a reduction of wing bud length. A piece of an E. festivellus nest with some third instar nymphs, soldiers and workers was kept under laboratory conditions. After 12 months, the whole experimental subcolony was examined and appeared to contain two pigmented nymphoid females...

Reproductive strategy of Coptotermes gestroi (Isoptera: Rhinotermitidae) in Brazil

Costa-Leonardo, Ana Maria; Arab, Alberto
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 123-125
ENG
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The termite Coptotermes gestroi (Wasmann) (Rhinotermitidae) is an exotic species in Brazil. This species forms colonies headed by primary reproductives, however, non-functional neotenics are commonly found even in the presence of the imaginai pair. The presence of non-functional neotenics in C. gestroi colonies may correspond to a strategy of this termite species for rapid colonization in foreign areas, instead of a response to chemical control methods.

Etnobotânica quantitativa de plantas do Cerrado e extrativismo de Mangaba (Hancornia speciosa Gomes) no norte de Minas Gerais : implicações para o manejo sustentável

Lima, Isabela Lustz Portela
Fonte: Universidade de Brasília Publicador: Universidade de Brasília
Tipo: Dissertação
POR
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Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Ecologia, Programa de Pós-Graduação em Ecologia, 2008.; Com o objetivo de identificar o potencial da vegetação para o extrativismo, o conhecimento sobre uso de recursos vegetais nativos pela comunidade local e estimar a taxa máxima de coleta sustentável dos frutos de mangaba (Hancornia speciosa Gomes, Apocynaceae), foi realizado um estudo em uma área de cerrado remanescente na comunidade Água Boa 2, município de Rio Pardo de Minas, Norte de Minas Gerais. Na primeira parte do estudo, foi feito um levantamento fitossociológico e conduzidas entrevistas estruturadas com uma listagem livre sobre as dez plantas frutíferas e as dez madeireiras nativas mais usadas, seus principais locais de coleta e formas de uso, relacionando as informações com as categorias de gênero e idade. Na segunda parte, foi avaliada a estrutura e a dinâmica populacional, a produtividade e a germinação de H. speciosa, cujos frutos são explorados e comercializados. Também foram realizadas entrevistas semi-estruturadas com os extrativistas para caracterização da coleta de mangaba e da sua contribuição na renda familiar. No total, foram amostrados 673 indivíduos arbóreos...

Multiple reproductives in nests of the Neotropical termite Constrictotermes cyphergaster (Isoptera, Termitidae, Nasutitermitinae)

Cunha,Hélida Ferreira da; Brandão,Divino
Fonte: Sociedade Brasileira De Entomologia Publicador: Sociedade Brasileira De Entomologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2002 EN
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Constrictotermes cyphergaster (Silvester, 1901) builds arboreal nests in Brazilian Cerrado stricto sensu, which are frequently cohabited by inquilines termites and by termitophiles. In a study made at the Parque Estadual da Serra de Caldas Novas, Goiás, Brazil, there were four nests with multiple reproductives, and secondary reproductives were found in 26 nests. Nymphs of Inquilinitermes were more abundant (9,47%) than nymphs of C. cyphergaster (0,78%).

Disease risk as a cost of outbreeding in the termite Zootermopsis angusticollis.

Rosengaus, R B; Traniello, J F
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/07/1993 EN
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The effect of the sibship of primary reproductives on mate mortality and the survivorship and growth of incipient colonies was studied in the dampwood termite Zootermopsis angusticollis. Males and females paired with nonsibling mates had higher mortality during the first 10-40 days after pairing, although male and female reproductives showed similar patterns of mortality after colony establishment. The source of mortality appeared to be fungal and/or bacterial pathogens. There were no overall differences in the number of eggs and larvae produced by sibling and nonsibling pairs, and no differences in colony size and biomass 4 years after colony establishment. We therefore could not identify any negative effect of inbreeding in the early phases of colony development. Our results suggest that the risk of exposure to pathogens and the ability of termites to locally adapt to disease could influence the genetic identity of primary reproductives and the extent of inbreeding in termite populations.

Evolution of eusociality and the soldier caste in termites: Influence of intraspecific competition and accelerated inheritance

Thorne, Barbara L.; Breisch, Nancy L.; Muscedere, Mario L.
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
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We present new hypotheses and report experimental evidence for powerful selective forces impelling the evolution of both eusociality and the soldier caste in termites. Termite ancestors likely had a nesting and developmental life history similar to that of the living family Termopsidae, in which foraging does not occur outside the host wood, and nonsoldier helpers retain lifelong options for differentiation into reproductives. A local neighborhood of families that live exclusively within a limited resource results in interactions between conspecific colonies, high mortality of founding reproductives, and opportunities for accelerated inheritance of the nest and population by offspring that differentiate into nondispersing neotenic reproductives. In addition, fertile reproductive soldiers, a type of neotenic previously considered rare and docile, frequently develop in this intraspecific competitive context. They can be highly aggressive in subsequent interactions, supporting the hypothesis that intercolonial battles influenced the evolution of modern sterile termite soldier weaponry and behaviors.

The origins and relatedness of multiple reproductives in colonies of the termite Nasutitermes corniger

Atkinson, L.; Adams, E. S.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 22/08/1997 EN
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Colonies of the termite Nasutitermes corniger often contain multiple reproductive queens and kings. We used double-strand conformation polymorphism (DSCP) analysis of mitochondrial DNA (mtDNA) to determine the probable origins of co-occurring reproductives. Colonies differed in queen and king number, in the number of nests containing reproductives, and in the genetic relationships among reproductives. Most of the 44 colonies contained a single pair of maternally unrelated reproductives. In the two single-nest colonies with a pair of queens, the two queens differed in mtDNA haplotype, suggesting nest-founding by unrelated queens. In the seven single-nest colonies with larger numbers of reproductives (11–49), all reproductives shared the same haplotype, a pattern consistent with replacement of a single pair by several offspring. As predicted by theory, the number of coexisting queens was greater for replacement reproductives than for co-foundresses. Several complex colonies contained multiple queens of two or more haplotypes distributed among several interconnected nests. This indicates that several matrilines can persist within a colony through one or more generations of budding and replacement, a hypothesis confirmed by orphaning experiments. The various modes of termite colony formation rival the diversity seen in ant species and demonstrate the remarkable convergence of behaviours between the two groups.

Beyond cuticular hydrocarbons: evidence of proteinaceous secretion specific to termite kings and queens

Hanus, Robert; Vrkoslav, Vladimír; Hrdý, Ivan; Cvačka, Josef; Šobotník, Jan
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
EN
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In 1959, P. Karlson and M. Lüscher introduced the term ‘pheromone’, broadly used nowadays for various chemicals involved in intraspecific communication. To demonstrate the term, they depicted the situation in termite societies, where king and queen inhibit the reproduction of nest-mates by an unknown chemical substance. Paradoxically, half a century later, neither the source nor the chemical identity of this ‘royal’ pheromone is known. In this study, we report for the first time the secretion of polar compounds of proteinaceous origin by functional reproductives in three termite species, Prorhinotermes simplex, Reticulitermes santonensis and Kalotermes flavicollis. Aqueous washes of functional reproductives contained sex-specific proteinaceous compounds, virtually absent in non-reproducing stages. Moreover, the presence of these compounds was clearly correlated with the age of reproductives and their reproductive status. We discuss the putative function of these substances in termite caste recognition and regulation.

Energy Pooling and Implications for the Unique Traits of the Human Life History Strategy

Sharrock, Katherine C.; Ellison, Peter; Lipson, Susan F.; Reiches, Meredith W.; Kramer, Karen L.
Fonte: John Wiley & Sons Publicador: John Wiley & Sons
EN_US
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Compared to non-human primates, human life history is characterized by slow juvenile growth, late age at maturity, short interbirth intervals, and a decoupling of reproductive senescence and somatic senescence. Some of these traits represent a delay of reproductive effort while others represent an acceleration. To address this puzzle, we propose that humans in all three stages of the life span, pre-reproductives, adults of reproductive age, and post-reproductives, all contribute to a “pooled energy budget” (PEB) that is primarily utilized by the reproductively active female to carry out the energetically expensive tasks of gestation and lactation. Adults contribute to the pooled energy budget by providing food and care to children, thus freeing up the mother to provide more resources to a gestating fetus or a nursing infant and to resume postpartum ovulation more quickly. Pre-reproductives also contribute to the PEB. Older children, through participating in childcare and subsistence activities, can provide resources to partially meet their own energetic needs and to care for and provision younger siblings. The mother becomes the “final common pathway” through which energy flows in order to produce new offspring. While life history theory has traditionally considered growth...

Fécondité, réseaux familiaux et scolarisation des enfants en milieu urbain au Burkina Faso

Bougma, Moussa
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
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La baisse de la fécondité permet aux couples d'investir davantage dans la scolarité de chacun de leurs enfants (évidence dans les pays occidentaux, d’Asie et d’Amérique latine). Ce postulat est l’un des arguments clés des politiques de planification familiale en Afrique subsaharienne. Pourtant, la plupart des études sur l'Afrique ont trouvé une corrélation nulle ou même une relation positive entre le nombre d'enfants dans un ménage et leur niveau de scolarité. Ces résultats mitigés sont généralement expliqués par des solidarités familiales et des transferts de ressources qui pourraient réduire la pression occasionnée par une descendance nombreuse sur les ressources du ménage, et des problèmes méthodologiques inhérents à plusieurs recherches sur la région. L’objectif principal de cette thèse était d’apporter une contribution à une meilleure compréhension des aspects méthodologiques et substantiels relatifs aux liens entre fécondité et scolarisation. Spécifiquement, la thèse visait à évaluer 1) le rôle des réseaux familiaux dans la scolarisation des enfants, 2) la simultanéité des décisions portant sur le nombre d’enfants et leur scolarisation, 3) l’impact causal du nombre d’enfants sur leur scolarisation...

Socially induced brain development in a facultatively eusocial sweat bee Megalopta genalis (Halictidae)

Smith, Adam R.; Seid, Marc A.; Jiménez, Lissette C.; Wcislo, William T.
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
EN
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Changes in the relative size of brain regions are often dependent on experience and environmental stimulation, which includes an animal's social environment. Some studies suggest that social interactions are cognitively demanding, and have examined predictions that the evolution of sociality led to the evolution of larger brains. Previous studies have compared species with different social organizations or different groups within obligately social species. Here, we report the first intraspecific study to examine how social experience shapes brain volume using a species with facultatively eusocial or solitary behaviour, the sweat bee Megalopta genalis. Serial histological sections were used to reconstruct and measure the volume of brain areas of bees behaving as social reproductives, social workers, solitary reproductives or 1-day-old bees that are undifferentiated with respect to the social phenotype. Social reproductives showed increased development of the mushroom body (an area of the insect brain associated with sensory integration and learning) relative to social workers and solitary reproductives. The gross neuroanatomy of young bees is developmentally similar to the advanced eusocial species previously studied, despite vast differences in colony size and social organization. Our results suggest that the transition from solitary to social behaviour is associated with modified brain development...

The Development of Adultoid Reproductives and Brachypterous Neotenic Reproductives From the Last Instar Nymphs in Reticulitermes labralis (Isoptera: Rhinotermitidae): A Comparative Study

Su, Xiao Hong; Xue, Wei; Liu, He; Chen, Jiao Ling; Zhang, Xiao Jing; Xing, Lian Xi; Liu, Ming Hua
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica
Publicado em 22/10/2015 EN
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Secondary reproductives develop primarily from nymphs. However, they have been rarely studied; in particular, the development of adultoid reproductives (AR) with floppy wings is still unclear. In this study, the change in juvenile hormone (JH) levels, vitellogenin gene expression, and oogenesis during the development of AR and brachypterous neotenic reproductives (BN) from the last instar nymphs of Reticulitermes labralis are investigated and compared. The results showed that the AR derived from the last instar nymphs by molting, and they were more similar to neotenic reproductives in morphology. In addition, the paired AR were not able to survive in the absence of workers. In R. labralis, the process of the last instar nymphs developing into AR and BN took an increase in JH level as a starting point. The JH level of the last instar nymphs molting into BN was approximately 1.5-fold higher than that of the AR. Additionally, The JHIII level of BN peaked on day 5, and that of AR peaked on day 10, which induced the onset of vitellogenesis in BN and AR, respectively. After molting, the vitellogenin gene expression levels of both BN and AR initially increased and then declined, and the expression levels in the BN were significantly higher than those in the AR. In addition...

Tecnologies reproductives aplicades a la conservació del burro Català

Taberner Brugué, Ester
Fonte: [Barcelona] : Universitat Autònoma de Barcelona, Publicador: [Barcelona] : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2011 CAT
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L'objectiu general d'aquesta tesi és l'estudi de les característiques reproductives del mascle i de la femella del burro Català per aplicar tecnologies reproductives que potenciïn la seva cria i evitin l'extinció d'aquesta raça de burro.; En conclusió, una predicció adequada de l'ovulació de les burres, juntament amb l'utilització dels mètodes òptims de maneig i congelació del semen de ruc Català contribuiran positivament a l'aplicació de tecnologies reproductives en programes de cria que ajudin a evitar l'extinció d'aquesta raça. 60%) spermatozoa had higher penetration percentage than fresh or frozen/thawed low viability ( 40%) spermatozoa. A significant positive correlation (P 0.01) was detected between percentage fertilization and viability (r=0.84), and between percentage fertilization and certain CASA parameters (VAP, r=0.56; VCL, r=0.61; and mean ALH, r=0.68). In conclusion, the exact moment prediction of ovulation in Catalonian jennies and adequate donkey semen manipulation and cryopreservation should have a positive impact upon the reproductive technologies application. Such knowledge should help maximize the production of live foals and help conserve the breed.

Mujeres inmigrantes y/o esposas de inmigrantes senegaleses y gambianos en Cataluña (España) : entre la vida familiar y la vida profesional

Sow, Papa
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Article; info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2004 SPA
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La inmigración de mujeres de origen senegalés y gambiano en Cataluña (España) es actualmente una realidad. Esta inmigración se beneficia de las medidas de reagrupamiento familiar instauradas por las autoridades españolas. El presente estudio permite conocer mejor estas familias recientemente instaladas, sus características productivas y reproductivas. A pesar del enrarecimiento del mercado de trabajo y las características del reagrupamiento familiar que frecuentemente les impiden trabajar fuera del domicilio conyugal, estas mujeres inmigrantes (o esposas de inmigrantes) encuentran otras posibilidades en Cataluña. Sobre todo las esposas jóvenes se lanzan al desafío de renovarse profesionalmente.; La immigració de dones d'origen senegalès i gambià a Catalunya (Espanya) és actualment una realitat. Aquesta immigració es beneficia de les mesures de reagrupament familiar instaurades per les autoritats espanyoles. Aquest estudi permet conèixer millor aquestes famílies recentment instal•lades, llurs característiques productives i reproductives. Malgrat l'enrariment del mercat de treball i les característiques del reagrupament familiar que moltes vegades els impedeixen treballar fora del domicili conjugal, aquestes dones immigrants (o esposes d'immigrants) troben altres possibilitats a Catalunya. Especialment les esposes joves accepten el desafiament de renovar-se professionalment.; L'immigration des femmes d'origine sénégalaise et gambienne en Catalogne (Espagne) est maintenant devenue une réalité. Cette immigration bénéficie de la faveur des mesures de regroupement familial instaurées par les autorités espagnoles. Cette présente étude permet de mieux connaître ces familles nouvellement installées...