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1.
Animal ; 15(1): 100053, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33515992

RESUMEN

Wild and farmed animals are key elements of natural and managed ecosystems that deliver functions such as pollination, pest control and nutrient cycling within the broader roles they play in contributing to biodiversity and to every category of ecosystem services. They are subjected to global changes with a profound impact on the natural range and viability of animal species, the emergence and spatial distribution of pathogens, land use, ecosystem services and farming sustainability. We urgently need to improve our understanding of how animal populations can respond adaptively and therefore sustainably to these new selective pressures. In this context, we explored the common points between animal production science and animal ecology to identify promising avenues of synergy between communities through the transfer of concepts and/or methodologies, focusing on seven concepts that link both disciplines. Animal adaptability, animal diversity (both within and between species), selection, animal management, animal monitoring, agroecology and viability risks were identified as key concepts that should serve the cross-fertilization of both fields to improve ecosystem resilience and farming sustainability. The need for breaking down interdisciplinary barriers is illustrated by two representative examples: i) the circulation and reassortment of pathogens between wild and domestic animals and ii) the role of animals in nutrient cycles, i.e. recycling nitrogen, phosphorus and carbon through, for example, contribution to soil fertility and carbon sequestration. Our synthesis identifies the need for knowledge integration techniques supported by programmes and policy tools that reverse the fragmentation of animal research toward a unification into a single Animal Research Kinship, OneARK, which sets new objectives for future science policy. At the interface of animal ecology and animal production science, our article promotes an effective application of the agroecology concept to animals and the use of functional diversity to increase resilience in both wild and farmed systems. It also promotes the use of novel monitoring technologies to quantify animal welfare and factors affecting fitness. These measures are needed to evaluate viability risk, predict and potentially increase animal adaptability and improve the management of wild and farmed systems, thereby responding to an increasing demand of society for the development of a sustainable management of systems.


Asunto(s)
Ecología , Ecosistema , Agricultura , Animales , Biodiversidad , Granjas
2.
Bioinspir Biomim ; 13(1): 011001, 2017 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-29130885

RESUMEN

Birds and mammals have evolved many thermal adaptations that are relevant to the bioinspired design of temperature control systems and energy management in buildings. Similar to many buildings, endothermic animals generate internal metabolic heat, are well insulated, regulate their temperature within set limits, modify microclimate and adjust thermal exchange with their environment. We review the major components of animal thermoregulation in endothermic birds and mammals that are pertinent to building engineering, in a world where climate is changing and reduction in energy use is needed. In animals, adjustment of insulation together with physiological and behavioural responses to changing environmental conditions fine-tune spatial and temporal regulation of body temperature, while also minimizing energy expenditure. These biological adaptations are characteristically flexible, allowing animals to alter their body temperatures to hourly, daily, or annual demands for energy. They exemplify how buildings could become more thermally reactive to meteorological fluctuations, capitalising on dynamic thermal materials and system properties. Based on this synthesis, we suggest that heat transfer modelling could be used to simulate these flexible biomimetic features and assess their success in reducing energy costs while maintaining thermal comfort for given building types.


Asunto(s)
Aves/fisiología , Regulación de la Temperatura Corporal/fisiología , Vivienda , Mamíferos/fisiología , Adaptación Biológica , Tejido Adiposo , Animales , Conducta Animal , Aves/anatomía & histología , Temperatura Corporal , Metabolismo Energético , Calor , Humanos , Integumento Común/fisiología , Mamíferos/anatomía & histología , Viento
4.
Int J Parasitol ; 42(8): 781-8, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22732161

RESUMEN

Wild birds are important hosts for vector-borne pathogens, especially those borne by ticks. However, few studies have been conducted on the role of different bird species within a community as hosts of vector-borne pathogens. This study addressed individual and species factors that could explain the burden of Ixodes ricinus on forest birds during the reproductive periods of both vectors and hosts. The goal was to identify which bird species contribute the most to the tick population at the community level. Birds were mist-netted on four plots in 2008 and on seven plots in 2009 in two forests (Sénart and Notre Dame, near Paris, France). The dependence of the tick load per bird upon environmental conditions (questing nymph density, year and plot) and on host species traits (species, age, sex, body size, vertical space use, level of innate and acquired immunity) was analysed. Finally, the relative contribution of each bird species to the local dynamics of ticks was estimated, while accounting for their respective abundance. Tick burden differed markedly between bird species and varied according to questing nymph density. Bird species with a high body mass, those that forage low in the vegetation, and those that had a high innate immune response and a high spleen mass were more likely to have a high tick burden. Four species (the Common Blackbird, Turdus merula, the European Robin, Erithacus rubecula, the Song Thrush, Turdus philomelos, and the Winter Wren, Troglodytes troglodytes) hosted more than 90% of the ticks in the local bird community. These species, and particularly T. merula which was host to a high proportion of the nymphs, are likely to contribute significantly to the circulation of pathogens for which they are competent, such as the agent of Lyme borreliosis.


Asunto(s)
Vectores Arácnidos/microbiología , Aves/parasitología , Borrelia burgdorferi/fisiología , Especificidad del Huésped , Ixodes/microbiología , Ixodes/fisiología , Enfermedad de Lyme/microbiología , Animales , Animales Salvajes/clasificación , Animales Salvajes/parasitología , Animales Salvajes/fisiología , Aves/clasificación , Aves/fisiología , Cruzamiento , Femenino , Francia , Humanos , Enfermedad de Lyme/transmisión , Masculino , Estaciones del Año
5.
Ageing Res Rev ; 11(1): 150-62, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21802530

RESUMEN

The use of non-human primate models is required to understand the ageing process and evaluate new therapies against age-associated pathologies. The present article summarizes all the contributions of the grey mouse lemur Microcebus murinus, a small nocturnal prosimian primate, to the understanding of the mechanisms of ageing. Results from studies of both healthy and pathological ageing research on the grey mouse lemur demonstrated that this animal is a unique model to study age-dependent changes in endocrine systems, biological rhythms, thermoregulation, sensorial, cerebral and cognitive functions.


Asunto(s)
Envejecimiento/patología , Envejecimiento/fisiología , Cheirogaleidae/fisiología , Modelos Animales , Animales , Humanos , Especificidad de la Especie , Investigación Biomédica Traslacional/métodos , Investigación Biomédica Traslacional/tendencias
6.
Indian J Pediatr ; 76(1): 99-101, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19391012

RESUMEN

Primary Foetal Hydrothorax (PFHT), is an intrathoracic collection of fluid in the fetus, which may be present on either side or even bilaterally. Advances in foetal diagnostics now allow consideration of the Ex-utero Intrapartum Treatment (EXIT) procedure for PFHT. Ex-utero Intrapartum Treatment (EXIT) allows therapeutic interventions on the neonate while maintaining fetoplacental circulation and thereby maintaining oxygenation. We report two cases of bilateral PFHT managed successfully with EXIT procedure.


Asunto(s)
Enfermedades Fetales/cirugía , Hidrotórax/embriología , Hidrotórax/cirugía , Procedimientos Quirúrgicos Obstétricos/métodos , Adulto , Cesárea , Femenino , Edad Gestacional , Humanos , Embarazo , Tercer Trimestre del Embarazo
7.
Am J Physiol Regul Integr Comp Physiol ; 295(2): R696-703, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18550867

RESUMEN

Cold resistance appears altered with aging. Among existing hypotheses, the impaired capacity in response to cold could be related to an altered regulation of plasma IGF-1 concentration. The combined effects of age and cold exposure were studied in a short-living primate, the gray mouse lemur (Microcebus murinus), which adjusts its energy balance using a daily torpor phase, to avoid high energy cost of normothermia maintenance. Changes in body mass, core temperature, locomotor activity, and caloric intake were monitored under 9-day exposures to 25 degrees C and 12 degrees C in captive animals in winter conditions. Short-term (after 2 days) and long-term (after 9 days) cold-induced changes in IGF-1 levels were also evaluated. In thermoneutral conditions (25 degrees C), general characteristics of the daily rhythm of core temperature were preserved with age. At 12 degrees C, age-related changes were mainly characterized by a deeper hypothermia and an increased frequency of torpor phases, associated with a loss of body mass. A short-term cold-induced decrease in plasma IGF-1 levels was observed. IGF-1 levels returned to basal values after 9 days of cold exposure. No significant effect of age could be evidenced on IGF-1 response. However, IGF-1 levels of cold-exposed aged animals were negatively correlated with the frequency of daily torpor. Responses exhibited by aged mouse lemurs exposed to cold revealed difficulties in the maintenance of normothermia and energy balance and might involve modulations of IGF-1 levels.


Asunto(s)
Sistema Nervioso Autónomo/fisiología , Regulación de la Temperatura Corporal , Cheirogaleidae/fisiología , Frío , Factores de Edad , Animales , Temperatura Corporal , Peso Corporal , Ritmo Circadiano , Ingestión de Energía , Metabolismo Energético , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Actividad Motora , Factores de Tiempo
9.
Heredity (Edinb) ; 95(6): 428-36, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16175196

RESUMEN

Although reproductive assurance (RA) might play a central role in the evolution of the selfing rate, this hypothesis has never been seriously investigated in an hermaphroditic animal. We studied the mating system of the freshwater snail Physa acuta in which the availability of mating partners might be highly variable, because this species is an efficient colonizer occupying unstable habitats. A total of 11 populations differing in ecological disturbance regime (water level, openness) and snail densities were monitored over 2 years. The outcrossing rate was estimated in ca 10 families per population using microsatellite markers and the progeny-array approach. Components of fecundity and survival were recorded for each progeny. Predominant outcrossing (t(m)=0.94) was detected, with a few individuals (4%) purely selfing. The outcrossing rate did not explain among-family variation in fitness components. None of the predictions formulated under the RA hypothesis were verified: (i) selfing was related neither to disturbed habitats, nor to temporal density fluctuations, (ii) it was positively related to population density, (iii) it co-occurred with multiple paternity, and (iv) it did not induce delayed reproduction. Explanations for these negative results are discussed in light of other arguments supporting the RA hypothesis in P. acuta, as well as alternative theories explaining the occurrence of partial selfing, as either a genetically fixed or plastic trait.


Asunto(s)
Ecología , Endogamia , Caracoles/genética , Animales , Femenino , Masculino , Reproducción/fisiología , Caracoles/fisiología
10.
Mol Ecol ; 13(7): 2023-36, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15189223

RESUMEN

Abstract The respective role of factors acting on population functioning can be inferred from a variety of approaches, including population genetics and demography. We here investigated the role of four of these factors (mating systems, population size, bottlenecks and migration) in the hermaphroditic freshwater snail Physa acuta. Twenty-four populations were sampled either around Montpellier (local scale), or at the scale of France (global scale). At local scale, eight populations were sampled twice, before and after summer drying out. The genetic structure of these populations was studied using microsatellite loci. Populations were classified according to openness (ponds vs. rivers) and water regime (permanent vs. temporary) allowing predictions on genetic patterns (e.g. diversity within populations and differentiation). At local scale, progeny-arrays analysis of the selfing rate was conducted, and size distributions of individuals were followed over two years. Results with regard to the four factors mentioned above were: (i) Estimates of population selfing rates derived from inbreeding coefficients were only slightly higher than those from progeny-arrays. (ii) More variation was detected in rivers than in ponds, but no influence of water regime was detected. One reason might be that permanent populations are not going less often through low densities than those from temporary habitats at the time scale studied. (iii) There was limited evidence for genetic bottlenecks which is compatible with the fact that even marked reduction in water availability was not necessarily associated with demographic bottlenecks. More generally, bottlenecks reducing genetic variation probably occur at population foundation. (iv) Lower genetic differentiation was detected among rivers than among ponds which might be related to limitations on gene flow. Demographic and temporal genetic data further indicates that flooding in rivers is unlikely to induce marked gene flow explaining the strong genetic differentiation at short geographical scale in such habitats. Finally, the demographic data suggest that some populations are transitory and subject to recurrent recolonization, a pattern that was also detected through genetic data.


Asunto(s)
Variación Genética , Genética de Población , Modelos Genéticos , Conducta Sexual Animal/fisiología , Caracoles/genética , Animales , Demografía , Francia , Agua Dulce , Frecuencia de los Genes , Repeticiones de Microsatélite/genética , Dinámica Poblacional , Reproducción/fisiología
11.
J Evol Biol ; 16(6): 1211-22, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14640413

RESUMEN

Inbreeding depression was simultaneously studied under contrasted environments, laboratory and natural conditions, using individuals originating from 14 families of the freshwater snail Physa acuta. Both survival and growth of juveniles showed inbreeding depression under laboratory conditions. The same fitness components were monitored with mature snails either kept under laboratory conditions or released at a natural site and analysed using capture-mark-recapture models. Genetic composition of both samples was similar. Inbreeding depression on survival was highest in the laboratory while strong outbreeding depression was revealed in the field. Thus inbreeding depression may not be always higher under natural conditions, at the opposite of what is commonly assumed. We suggest that inbreeding depression is dependent on metabolic requirements imposed by the environment. Other evidences showing that inbreeding depression is environment-dependent are reviewed. We conclude that genetic models should include both genetic and environmental variance in inbreeding depression for studying mating system evolution.


Asunto(s)
Trastornos del Desarrollo Sexual , Endogamia , Modelos Genéticos , Caracoles/genética , Adaptación Fisiológica , Animales , Ambiente , Femenino , Variación Genética , Masculino , Dinámica Poblacional , Caracoles/crecimiento & desarrollo , Caracoles/fisiología
12.
Parasitology ; 127(Pt 3): 243-51, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12964827

RESUMEN

The population biology of the schistosome-vector snail Bulinus truncatus was studied in an irrigation area near Marrakech, Morocco, using demographic approaches, in order to estimate life-history parameters. The survey was conducted using 2 capture-mark-recapture analyses in 2 separate sites from the irrigation area, the first one in 1999 and the second one in 2000. Individuals larger than 5 mm were considered. The capture probability varied through time and space in both analyses. Apparent survival (from 0.7 to 1 per period of 2-3 days) varied with time and space (a series of sinks was considered), as well as a square function of size. These results suggest variation in population intrinsic rate of increase. They also suggest that results from more classical analyses of population demography, aiming, for example at estimating population size, should be interpreted with caution. Together with other results obtained in the same irrigation area, they also lead to some suggestions for population control.


Asunto(s)
Bulinus/crecimiento & desarrollo , Vectores de Enfermedades , Estadios del Ciclo de Vida , Animales , Marruecos , Dinámica Poblacional
13.
Genetika ; 39(6): 834-9, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12884525

RESUMEN

One hundred children with suspected congenital and/or malformation and their parents who reported to SAT hospital, Medical College, Trivandrum, India formed the test group. Fifty children with no obvious anomalies or abnormalities and their parents formed the control group. The criteria for selection of the control was 1) the maternal age at delivery was below 30 years and 2) the parents belong to 1st or 2nd birth order. The chromosomal analysis was carried out in all the subjects using peripheral blood lymphocyte microculture to investigate for any constitutional chromosomal markers and quantitate the mutagen (bleomycin) sensitivity of the chromosomes. All the subjects were evaluated clinically and a complete family history was recorded. Chromosome anomalies were noted in 41 out of the one hundred children and in 4 out of the 200 parents of the test group. No constitutional aberrations were seen either in the parents or in the children of the control group. Bleomycin sensitivity study revealed a high b/c value in 35 children (24 hypersensitive and 11 sensitive) of the test group whereas in the control group the b/c values were low denoting hyposensitivity and very good DNA repair mechanism. This study reveals that the incidence of chromosome aberrations is higher when the age and birth order of parents are higher. A direct correlation was noted with parental order and b/c value. This was also true with the parental age and birth defects.


Asunto(s)
Anomalías Múltiples/etiología , Orden de Nacimiento , Aberraciones Cromosómicas , Anomalías Múltiples/epidemiología , Anomalías Múltiples/genética , Adulto , Factores de Edad , Anciano , Bleomicina/toxicidad , Células Cultivadas , Salud de la Familia , Femenino , Humanos , Incidencia , India/epidemiología , Linfocitos/efectos de los fármacos , Linfocitos/fisiología , Masculino , Edad Materna , Persona de Mediana Edad , Mutágenos/toxicidad
14.
Parasitology ; 125(Pt 4): 349-57, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12403323

RESUMEN

The population biology of the schistosome-vector snail Bulinus truncatus was studied in an irrigation system near Marrakech, Morocco using both genetic and demographic approaches. The population genetic survey was conducted in 4 sites, 2 sites being sampled on 2 separate occasions. Individuals were genotyped at 6 microsatellite loci. No variability was found at 4 loci, and the 2 other loci had less than 4 alleles. The differentiation, both spatial and temporal, among populations was extremely weak. The demographic survey was conducted using 2 capture-mark-recapture analyses in 2 separate sites, the first in 1999 and the second in 2000. The second analysis permitted the estimation of parameters based on recent methodological developments (multisite models). Although these studies provided information on several traits, we report here on dispersal only. Both analyses showed that individual dispersal is of the order of a few hundreds of metres per reproductive life, that is the scale of the whole irrigation area. Both the genetic and demographic studies indicated that this area harbours a single--or no more than a few--populations of B. truncatus. This has implications for our understanding of the coevolutionary process between snails and flukes.


Asunto(s)
Bulinus/genética , Bulinus/fisiología , Vectores de Enfermedades , Variación Genética/genética , Schistosoma haematobium , Animales , Evolución Biológica , Bulinus/parasitología , Heterocigoto , Interacciones Huésped-Parásitos , Repeticiones de Microsatélite/genética , Marruecos , Dinámica Poblacional
15.
Proc Biol Sci ; 267(1439): 165-9, 2000 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-10687822

RESUMEN

Song repertoires (the number of different song types sung by a male) in birds provide males with an advantage in sexual selection because females prefer males with large repertoires, and females may benefit because offspring sired by preferred males have high viability. Furthermore, males with large repertoires suffer less from malarial parasites, indicating that a large repertoire may reflect health status. We hypothesize that sexual selection may cause a coevolutionary increase in parasite virulence and host immune defence because sexual selection increases the risk of multiple infections that select for high virulence. Alternatively, a female mate preference for healthy males will affect the coevolutionary dynamics of host-parasite interactions by selecting for increased virulence and hence high investment by hosts in immune function. In a comparative study of birds, repertoire size and relative size of the spleen, which is an important immune defence organ, were strongly, positively correlated accounting for almost half of the variance. This finding suggests that host-parasite interactions have played an important role in the evolution of song repertoires in birds.


Asunto(s)
Aves/fisiología , Animales , Evolución Biológica , Aves/inmunología , Inmunidad , Masculino , Vocalización Animal
17.
Cephalalgia ; 4(3): 171-8, 1984 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6437683

RESUMEN

Three cases of intracranial arteriopathy associated with the administration of ergot derivatives are reported. In the first case, excessive doses of dihydroergotamine and of ergotamine tartrate seemed to be the cause, but simultaneous treatment with an antibiotic and the existence of a cytomegalovirus infection could have favoured the arteriopathic process. The second patient also received excessive doses of these two drugs, but in addition she was taking oestrogen and progesteron containing contraceptives. In the third case, an intravenous injection of methylergometrine in a dose of 0.2 mg seemed to have initiated the arteriopathy. Arteriograms were comparable in all three cases, with segmental stenosis of several cerebral arteries, whereas internal carotid and vertebral arteries remained normal. In the first case a control cerebral arteriography was normal one month later. These findings suggest that widespread cerebral arteriopathy can appear in subjects who chronically abuse ergotamine tartrate.


Asunto(s)
Enfermedades Arteriales Cerebrales/inducido químicamente , Ergotaminas/efectos adversos , Adulto , Antibacterianos/efectos adversos , Dihidroergotamina/efectos adversos , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Ergotamina , Etinilestradiol/efectos adversos , Combinación Etinil Estradiol-Norgestrel , Femenino , Humanos , Metilergonovina/efectos adversos , Norgestrel/efectos adversos
18.
Nouv Presse Med ; 10(22): 1807-11, 1981 May 16.
Artículo en Francés | MEDLINE | ID: mdl-7232169

RESUMEN

In a series of 250 cases of cerebral vascular accident, the authors have selected 12 patients whose embolus appeared to have originated in the heart, although this could not be confirmed by clinical examination, ECG, Holter system monitoring and echocardiographic studies. Angiocardiography, complemented or not by His bundle exploration and/or coronary arteriography, revealed the presence of a heart disease likely to produce emboli in 11 cases, and in 8 cases, this was prolapsed mitral valve. These 11 cases represent 4.5% of the whole series and 22% of cases with emboli of suspected cardiac origin. Thorough cardiological studies, therefore, seem to be justified in young adults presenting with stroke. The high incidence of prolapsed mitral valve is in keeping with recently published data.


Asunto(s)
Cardiopatías/complicaciones , Embolia y Trombosis Intracraneal/etiología , Adolescente , Adulto , Angiocardiografía , Fascículo Atrioventricular/fisiopatología , Angiografía Coronaria , Ecocardiografía , Electrocardiografía , Femenino , Cardiopatías/diagnóstico , Humanos , Embolia y Trombosis Intracraneal/diagnóstico , Masculino , Persona de Mediana Edad
19.
Res Clin Stud Headache ; 6: 81-8, 1978.
Artículo en Inglés | MEDLINE | ID: mdl-725260

RESUMEN

CBF was studied in 15 cases of vascular headache by the 135Xe intra-arterial injection method. The mean CBF was found to be increased during the headache phase of the migraine attacks in half the cases, mainly due to an increase in the rapid component (CBFg). After the attack there could be an increase or a decrease of the slow component (CBFw). Reactivity to anaesthetic depression was studied in 8 migraine cases and on the whole it was found not to be much altered in most cases. Finally, no modifications of CBF were found in any of 3 cases of cluster headache who were studied during attacks of severe pain.


Asunto(s)
Circulación Cerebrovascular , Cefalalgia Histamínica/fisiopatología , Trastornos Migrañosos/fisiopatología , Cefalalgias Vasculares/fisiopatología , Mezcla de Alfaxalona Alfadolona/farmacología , Dióxido de Carbono/sangre , Circulación Cerebrovascular/efectos de los fármacos , Diazepam/farmacología , Fentanilo/farmacología , Humanos , Consumo de Oxígeno/efectos de los fármacos
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