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1.
Entramado ; 19(1)jun. 2023.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1534414

RESUMEN

R E S U M E N Los diferentes actores del sector deportivo tienen la responsabilidad de formular y respaldar las políticas asociadas al deporte, la recreación y la actividad física. Sin embargo, la escasa investigación del deporte como medio de desarrollo social dificulta la rigurosidad en la definición de las políticas, e incluso la identificación de los actores y sus responsabilidades. Por lo anterior; el presente artículo de investigación establece los actores de la política pública del sector del deporte, la recreación y la actividad física, y analiza estructural y posicionalmente la dinámica de esta red, evidenciando que el Estado ya no es el actor principal en la creación de políticas, sino que existen asociaciones público -privadas que inciden y deciden. De esta forma, se pretende estudiar cómo el deporte, influye en la consecución de los Objetivos de Desarrollo Sostenible ODS, promoviendo la construcción de paz y buena gobernanza desde sus instituciones (ODS I6), soportado por políticas públicas del deporte, la salud y la recreación, que apunten a construir comunidades sostenibles (ODS II).


The different actors in the sport sector are responsible for formulating and supporting policies associated with sport, recreation and physical activity However the scarce research on sport as a means of social development hinders the rigorous definition of policies, and even the identification of the actors and their responsibilities. Therefore,this research article establishes the actors ofpublic policy in the sector ofsport,recreation and physical activity and analyzes structurally and positionally the dynamics ofthis network,showing that the State is no longer the main actor in the creation of policies, but that there are public-private partnerships that influence and decide. In this way, the aim is to study how sport influences the achievement of the Sustainable Development Goals SDGs, promoting the construction of peace and good governance from its institutions (SDG I6), supported by public policies on sport, health and recreation, which aim to build sustainable communities (SDG II).


Os diferentes atores do setor esportivo têm a responsabilidade de formular e apoiar políticas associadas ao esporte, à recreação e à atividade física. Entretanto, a escassez de pesquisas sobre o esporte como meio de desenvolvimento social dificulta a definição rigorosa das políticas e até mesmo a identificação dos atores e de suas responsabilidades. Portanto, este artigo de pesquisa estabelece os atores das políticas públicas no setor de esporte, recreação e atividade física, e analisa estrutural e posicionalmente a dinâmica desta rede, mostrando que o Estado não é mais o principal ator na criação de políticas, mas que existem parcerias público-privadas que influenciam e decidem. Desta forma, o objetivo é estudar como o esporte influencia a realização dos Objetivos de Desenvolvimento Sustentável SDGs, promovendo a construção da paz e da boa governança a partir de suas instituições (SDG I6), apoiadas por políticas públicas sobre esporte, saúde e recreação, que visam a construção de comunidades sustentáveis (SDG II).

2.
Curr Biol ; 32(23): 5153-5158.e5, 2022 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-36288731

RESUMEN

Oscine birds preferentially respond to certain sounds over others from an early age, which focuses subsequent learning onto sexually relevant songs.1,2,3 Songs vary both across species and, due to cultural evolution, among populations of the same species. As a result, early song responses are expected to be shaped by selection both to avoid the fitness costs of cross-species learning4 and to promote learning of population-typical songs.5 These sources of selection are not mutually exclusive but can result in distinct geographic patterns of song responses in juvenile birds: if the risks of interspecific mating are the main driver of early song discrimination, then discrimination should be strongest where closely related species co-occur.4 In contrast, if early discrimination primarily facilitates learning local songs, then it should be tuned to songs typical of the local dialect.5,6,7 Here, we experimentally assess the drivers of song discrimination in nestling pied flycatchers (Ficedula hypoleuca). We first demonstrate that early discrimination against the songs of the closely related collared flycatcher (F. albicollis) is not strongly affected by co-occurrence. Second, across six European populations, we show that nestlings' early song responses are tuned to their local song dialect and that responses to the songs of collared flycatchers are similarly weak as to those of other conspecific dialects. Taken together, these findings provide clear experimental support for the hypothesis that cultural evolution, in conjunction with associated learning predispositions, drives the emergence of pre-mating reproductive barriers.


Asunto(s)
Evolución Cultural
3.
Oecologia ; 199(1): 79-90, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35554681

RESUMEN

Floaters constitute the sexually mature but non-breeding part of populations. Despite being ubiquitous in most species, knowledge about floaters is scarce. Ignoring this significant number of individuals may strongly bias our understanding of population dynamics and sexual selection processes. We used the spotless starling (Sturnus unicolor) to examine whether phenotypical and non-phenotypical variables from early and adult life predict reproductive status, focusing on the earliest age at which most individuals start to breed, when the percentage of floaters is the highest. We compiled data from a long-term study involving eight female and seven male cohorts of individuals PIT-tagged at birth. We compared a suite of nestling (condition, hatching date and brood size) and adult variables (condition, size and ornamentation) between floaters and breeders. We found that adult and nestling body condition strongly and positively influenced the likelihood of breeding in males. Path analysis revealed that male reproductive status could only be predicted by considering nestling body condition-the influence of this variable superseded adult body condition. Female reproductive status was only negatively associated with hatching date. Ornamentation was not associated with reproductive status in any of the sexes, although path analyses revealed that body condition was positively associated with throat feather length. We conclude that predictors of reproductive status are sex-specific in the spotless starling, suggesting an important role of body condition in access to breeding resources in males. Our results also highlight the long-term influence of early life on life trajectories and their potential implications on floating status.


Asunto(s)
Reproducción , Estorninos , Animales , Cruzamiento , Plumas , Femenino , Humanos , Recién Nacido , Masculino , Conducta Sexual Animal
4.
Curr Zool ; 68(1): 27-40, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35169627

RESUMEN

Characterizing the diversity and structure of host-parasite communities is crucial to understanding their eco-evolutionary dynamics. Malaria and related haemosporidian parasites are responsible for fitness loss and mortality in bird species worldwide. However, despite exhibiting the greatest ornithological biodiversity, avian haemosporidians from Neotropical regions are quite unexplored. Here, we analyze the genetic diversity of bird haemosporidian parasites (Plasmodium and Haemoproteus) in 1,336 individuals belonging to 206 bird species to explore for differences in diversity of parasite lineages and bird species across 5 well-differentiated Peruvian ecoregions. We detected 70 different haemosporidian lineages infecting 74 bird species. We showed that 25 out of the 70 haplotypes had not been previously recorded. Moreover, we also identified 81 new host-parasite interactions representing new host records for these haemosporidian parasites. Our outcomes revealed that the effective diversity (as well as the richness, abundance, and Shannon-Weaver index) for both birds and parasite lineages was higher in Amazon basin ecoregions. Furthermore, we also showed that ecoregions with greater diversity of bird species also had high parasite richness, hence suggesting that host community is crucial in explaining parasite richness. Generalist parasites were found in ecoregions with lower bird diversity, implying that the abundance and richness of hosts may shape the exploitation strategy followed by haemosporidian parasites. These outcomes reveal that Neotropical region is a major reservoir of unidentified haemosporidian lineages. Further studies analyzing host distribution and specificity of these parasites in the tropics will provide important knowledge about phylogenetic relationships, phylogeography, and patterns of evolution and distribution of haemosporidian parasites.

5.
J Comp Physiol B ; 191(1): 195-206, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33196859

RESUMEN

Ecophysiological studies have highlighted the relevance of the avian immune system in individual fitness prospects in the wild. However, studies on the ontogeny of avian immunity are scarce. We analyse age-related changes in the cellular constitutive immunity throughout nestling development, as well as its relationship with sex and brood size. We found that cellular constitutive immunity could be affected by age, sex, brood size, or daily rhythm. Early-stage nestlings relied more on cells of the innate immunity rather than on cells linked to the adaptive immune system. Cellular immunity may not be fully mature in fledglings, as reflected by differences in phagocytic cell counts with regard to adults. Beyond the age-dependent effects, agranulocyte cell counts were affected by sibling competition while granulocyte cell counts showed a daily rhythm. We also show that the heterophil to lymphocyte ratio was negatively related to body weight when nestlings become more independent. Our study contributes knowledge to the fields of developmental immunology and ecological immunology based on essential components of the cellular immune system.


Asunto(s)
Inmunidad Innata , Passeriformes , Animales , Peso Corporal , Leucocitos
6.
J Evol Biol ; 32(1): 111-125, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30387533

RESUMEN

Stress during early development can induce substantial long-term effects in organisms. In the case of birds, despite growth compensations, nestlings reared under harsh conditions typically show reduced survival chances in adulthood. It has been proposed that environmental early-life stressors could affect longevity via effects on telomere length, possibly mediated through oxidative stress. However, the link between these processes is not clear. In this study, we experimentally manipulated brood size in spotless starlings (Sturnus unicolor) to test the causal relationship between early stress, oxidative and corticosterone-mediated stress and telomere shortening. Our results show that experimentally enlarged brood sizes led to a reduction in morphometric development on nestlings, the effect being stronger for females than males. Additionally, basal corticosterone levels increased with increasing brood size in female nestlings. Neither plasma antioxidant status nor malondialdehyde levels (a marker of lipid peroxidation) were affected by experimental brood size, although the levels of a key intracellular antioxidant (glutathione) decreased with increasing brood size. We found that the treatment showed a quadratic effect on nestling telomere lengths: these were shortened either by increases or by decreases in the original brood size. Our study provides experimental evidence for a link between developmental stress and telomere length, but does not support a direct causal link of this reduction with corticosterone or oxidative stress. We suggest that future studies should focus on how telomere length responds to additional markers of allostatic load.


Asunto(s)
Corticosterona/sangre , Estrés Oxidativo/fisiología , Estorninos , Animales , Antioxidantes/metabolismo , Femenino , Longevidad , Masculino , Estorninos/crecimiento & desarrollo , Estorninos/fisiología , Estrés Fisiológico , Acortamiento del Telómero
7.
Parasitol Res ; 117(3): 919-928, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29327322

RESUMEN

We studied the prevalence and genetic diversity of malaria parasites in the poorly investigated spotless starling (Sturnus unicolor) breeding in central Spain, aiming to describe the phylogenetic relationships among them and with other haemosporidians infecting the genus Sturnus. A total of 180 nestlings and 180 adult individuals from four different breeding seasons were screened for haemosporidian parasites using a nested PCR approach for the genera Plasmodium and Haemoproteus. Although the malaria prevalence ranged between years, the overall prevalence was 6.94%. Adults had a higher prevalence than chicks: 12.77 vs. 1.11%, respectively. We molecularly characterized avian malaria isolated in peripheral blood samples taken from malaria-infected individuals. Sequence analyses revealed four unique Plasmodium lineages of avian malaria (STURUNI01, STURUNI02, SYAT05, SGS1) in our spotless starling population. The phylogenetic analysis showed a well-supported clade comprised by STURUNI01, STURUNI02, and SYAT05. The most common lineage (SYAT05) has been previously found in 26 other avian host species, including populations of spotless starling in Portugal. Because this sedentary species is widely distributed throughout the Iberian Peninsula, we suggest that the local transmission of these lineages might place migratory birds at infection risk.


Asunto(s)
Malaria Aviar/parasitología , Plasmodium/clasificación , Estorninos/parasitología , Animales , Femenino , Variación Genética , Haemosporida/clasificación , Haemosporida/genética , Especificidad del Huésped , Malaria Aviar/epidemiología , Masculino , Filogenia , Plasmodium/genética , Prevalencia , España/epidemiología
8.
Oecologia ; 185(4): 629-639, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29018951

RESUMEN

Limited resources trigger trade-offs in resource allocation. Reproduction is one of the most demanding activities in terms of energy, and costs related to reproduction can be apparent either as reduced future reproduction or as survival. However, costs are not always detected, because individual heterogeneity in quality and resource acquisition may explain variation in costs among individuals. We conducted a comprehensive study in spotless starlings (Sturnus unicolor) nesting in Central Spain to determine whether costs of reproduction could be detectable in the short and/or long term and whether prenatal or postnatal investment were driving these costs. We took into account the life history of the species, where egg volume is highly repeatable, males are facultatively polygynous, and intraspecific brood parasitism occurs. Females with a high reproductive effort in a breeding event also had a high reproductive effort in the second event of the season. The mating system and maternal age were reliable predictors of breeding success within a breeding event: monogamous and primary females, as well as older mothers, raised more nestlings than secondary females and 1-year-old females, respectively. However, when high-investing females suffered intra-brood parasitism in 1 year, we found a negative correlation between current and future reproduction. These results suggest that, under some circumstances, females are able to skip the short-term costs of reproduction, but when extra effort is added, trade-offs arise. While most studies have focused on different aspects of individual quality on costs, the ecological context seems to represent an important component that should be taken into account.


Asunto(s)
Conducta Sexual Animal/fisiología , Animales , Metabolismo Energético , Femenino , Masculino , Passeriformes/fisiología , Reproducción/fisiología , Estaciones del Año , España
9.
Physiol Biochem Zool ; 90(1): 106-117, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28051945

RESUMEN

Avian embryos are exposed to yolk androgens that are incorporated into the egg by the ovulating female. These steroids can affect several aspects of embryo development, often resulting in increases in overall size or the speed of growth of different traits. However, several studies suggest that they also entail immune costs to the offspring. In this study, we explored whether variation in yolk androgen concentration affected several measures of the constitutive and cell-mediated immune axes in the spotless starling (Sturnus unicolor). Using a within-brood design, we injected different doses of androgens (testosterone and androstenedione) into the eggs. Our study showed that experimentally increased yolk androgens led to sex-specific immunosuppression in both the innate and adaptive axes of the immune system. Both cell-mediated immune response (CMI) and lysozyme activity decreased with increasing androgen levels injected into the egg in the case of male nestlings, whereas there were no effects on females. The effects that we found were always linear: no quadratic or threshold patterns were detected. We found no effects of the experimental treatment in hemolysis or agglutination capacity, but these measures were negatively correlated with CMI, suggesting negative correlation among different branches of the immune system. Blood (trypanosomes and hemosporidians) and intestinal (coccidia) parasites were not affected by the experimental increase of yolk androgen levels. Our results show that in our study species yolk androgens induce immunosuppression in some axes of the male nestling immune system. Further studies should analyze the proximate causes for these contrasting effects in different axes of the immune system and the reason for the differential impact on males and females.


Asunto(s)
Andrógenos/metabolismo , Yema de Huevo/química , Inmunidad Celular/fisiología , Inmunidad Humoral/fisiología , Passeriformes/fisiología , Aglutinación , Animales , Femenino , Hemólisis , Masculino , Muramidasa/sangre , Fitohemaglutininas/inmunología
10.
J Exp Biol ; 218(Pt 14): 2241-9, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25987739

RESUMEN

Avian egg yolks contain various amounts of maternally derived androgens that can modify offspring phenotype and adjust their development to the post-hatching environment. Seemingly adaptive variation in yolk androgen levels with respect to breeding density conditions or male attractiveness has been found in numerous studies. One important consideration that has been overlooked in previous research is the likely non-linear nature of hormone effects. To examine possible complex dose-response effects of maternal androgens on chick development, we experimentally administered three different androgen doses of the naturally occurring mixture of yolk testosterone and androstenedione to spotless starling eggs (Sturnus unicolor). We found that yolk androgens induce a non-linear dose-response pattern in several traits. Androgens had a stimulatory effect on hatchling body mass and nestling skeletal growth, but maximum values were found at intermediate doses, whereas our highest dose resulted in a decrease. However, the opposite U-shaped effect was found on nestling body mass. We also detected linear negative and positive effects on embryonic development period and nestling gape width, respectively. Our results suggest differential tissue responsiveness to yolk androgens, which may result in compromises in maternal allocation to produce adapted phenotypes. Because of the non-linear dose-response pattern, future investigations should carefully consider a wide range of concentrations, as the balance of costs and benefits may strongly differ depending on concentration.


Asunto(s)
Andrógenos/farmacología , Androstenodiona/farmacología , Estorninos/embriología , Estorninos/crecimiento & desarrollo , Testosterona/farmacología , Andrógenos/metabolismo , Androstenodiona/metabolismo , Animales , Animales Recién Nacidos , Peso Corporal/efectos de los fármacos , Desarrollo Óseo/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Yema de Huevo/química , Yema de Huevo/metabolismo , Desarrollo Embrionario/efectos de los fármacos , Femenino , Masculino , Fenotipo , Estorninos/metabolismo , Testosterona/metabolismo
11.
Physiol Biochem Zool ; 88(3): 345-51, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25860832

RESUMEN

Lipid peroxidation products are widely used as markers of oxidative damage in the organism. To properly interpret the information provided by these markers, it is necessary to know potential sources of bias and control confounding factors. Here, we investigated the relationship between two indicators of lipid mobilization (circulating levels of triglycerides and cholesterol) and two common markers of oxidative damage (plasma levels of malondialdehyde and hydroperoxides; the latter estimated from the d-ROMs assay kit). The following five avian species were studied: red-legged partridge (Alectoris rufa), zebra finch (Taeniopygia guttata), spotless starling (Sturnus unicolor), marsh harrier (Circus aeroginosus), and Montagu's harrier (Circus pygargus). In all cases, plasma triglyceride levels positively and significantly correlated with lipid peroxidation markers, explaining between 8% and 34% of their variability. Plasma cholesterol, in contrast, showed a significant positive relationship only among spotless starling nestlings and a marginally significant association in zebra finches. These results indicate that lipid peroxidation marker levels covary with circulating lipid levels. We discuss the potential causes and implications of this covariation and recommend that future studies that measure oxidative damage using lipid peroxidation markers report both raw and relative levels (i.e., corrected for circulating triglycerides). Whether the observed pattern also holds for other tissues and in other taxa would deserve further research.


Asunto(s)
Biomarcadores/sangre , Aves/sangre , Peroxidación de Lípido , Estrés Oxidativo , Animales , Colesterol/sangre , Peróxidos Lipídicos/sangre , Malondialdehído/sangre , Triglicéridos/sangre
12.
Gen Comp Endocrinol ; 194: 175-82, 2013 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-24090611

RESUMEN

Yolk androgens in avian eggs play a significant role in embryo and nestling development. However, few studies have examined the differential effect of two of the main yolk androgens, testosterone (T) and androstenedione (A4). Here, we injected eggs of spotless starlings with physiological levels of either T, A4, the combination T+A4 or vehicle substance (control), to examine the differential ability of these steroids to influence nestling development. We found that the duration of the embryonic period was increased by T, and less so by A4, but not by the combination T+A4. Body condition was reduced in all experimental treatments where A4 was present, particularly so in the combination T+A4. Tarsus length was increased in males by A4, and in a lower degree by T, whereas the combination T+A4 inhibited growth. However, these differences in tarsus length between groups disappeared at the end of the nestling period. Cell-mediated immune responsiveness was marginally affected by the interaction between treatment and sex. These patterns suggest that in this species, T has a stronger influence during embryo development than A4, whereas during nestling development the capacities of both androgens to influence growth are similar. The combination T+A4 showed non-additive effects, suggesting either some kind of inhibition between the two androgens, or else an excessive effect due to a bell-shaped pattern of response. Our results suggest a complex picture of sex and age-dependent effects of T and A4, and underline the necessity of further research in the metabolism and action of egg androgens.


Asunto(s)
Androstenodiona/metabolismo , Yema de Huevo/metabolismo , Estorninos/metabolismo , Testosterona/metabolismo , Animales , Femenino , Masculino , Comportamiento de Nidificación/fisiología , Estorninos/fisiología
13.
PLoS One ; 8(12): e84108, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24391896

RESUMEN

Several techniques in ecological immunology have been used to assess bird immunocompetence thus providing useful information to understand the contribution of the immunological system in life-history decisions. The phytohaemagglutinin (PHA)-skin test has been the most widely employed technique being interpreted as the sole result of T lymphocytes proliferation and hence used to evaluate acquired immunological capacity. However, the presence of high numbers of phagocytic cells in the swelling point has cast some doubt about such an assumption. To address this issue, we collected blood from 14 days-old nestlings of spotless starling (Sturnus unicolor), administered subcutaneous PHA immediately after and then measured the swelling response 24 hours later. Differential counts of white blood cells suggested that an intense development of acquired immunological defences was taking place. The phagocytic activity of both heterophiles and monocytes was also very intense as it was the swelling response. Moreover, our results show, for the first time in birds, a positive relationship between the phagocytic activity of both kinds of cells and the swelling response. This broadens the significance of the PHA test from reflecting T lymphocytes proliferation -as previously proposed but still undetermined in vivo- to evaluate phagocytosis as well. In other words, our data suggest that the PHA swelling response may not be considered as the only consequence of processes of specific and induced immunity -T lymphocytes proliferation- but also of constitutive and nonspecific immunity -heterophiles and monocytes phagocytosis. We propose the extensive use of PHA-skin test as an optimal technique to assess immunocompetence.


Asunto(s)
Pruebas Inmunológicas/métodos , Activación de Linfocitos/inmunología , Monocitos/inmunología , Fagocitosis/fisiología , Fitohemaglutininas/inmunología , Estorninos/inmunología , Linfocitos T/inmunología , Animales , Inmunidad Innata , Inmunocompetencia/inmunología
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