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1.
Zoolog Sci ; 41(2): 201-209, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38587915

RESUMO

Dispersal increases the costs of feeding and predation risk in the new environment and is reported to be biased toward habitats similar to the natal region in some mammals. The benefits and costs of dispersal often differ between sexes, and most mammals show male-biased dispersal in relation to a polygamous mating system. Japanese serow is generally a solitary and monogamous species. However, recent studies have shown that the sociality of serows on Mt. Asama differs between habitat types. In the mountain forests with low forage availability, solitary habits and social monogamy were observed, while, in alpine grasslands, female grouping and social polygyny were observed, which is probably due to abundant forage availability. We investigated the effects of habitat characteristics and sociality on the dispersal of serows using fecal and tissue samples from two different habitats on Mt. Asama. The Fst value between the two areas was significantly positive, and the mean relatedness within areas was significantly higher than that between areas, which suggests limited gene flow and natal habitat-biased dispersal. Bayesian clustering analysis showed unidirectional gene flow from forest to grassland, which was probably due to the high forage availability of the grassland. Analyses of the assignment index and mean relatedness did not show male-biased dispersal, even in the grassland, where serows were polygynous. Thus, polygyny in the grassland is not linked to male-biased dispersal. In summary, our study suggests that dispersal patterns in Japanese serows are affected by habitat rather than social differences.


Assuntos
Ecossistema , Mamíferos , Feminino , Masculino , Animais , Teorema de Bayes , Japão
2.
Animals (Basel) ; 14(13)2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38998036

RESUMO

It has been known that harvesting by humans strongly influences individual within-home range habitat selection of many deer species; however, little is known about the effect of harvesting on coarse-scale habitat selection (i.e., spatial distribution). We examined the summer spatial distribution of sika deer Cervus nippon in relation to human harvesting and other factors, such as human residences, forage abundance, and cover, using pellet group counts at Mount Fuji, central Japan, in 2018. In the study area, harvesting is conducted at medium elevation areas throughout the year, but not at high or low elevation areas where access is difficult or harvesting is prohibited. Spatial distribution of deer was significantly biased to non-harvesting areas and far from residential areas, suggesting that they avoid riskier spaces by establishing a landscape of fear. High-quality food resources (deciduous broad-leaved trees and forbs) were more abundant in harvesting areas than in non-harvesting areas, suggesting that foraging pressure by deer reduce them. However, there were no differences in abundances of more fibrous dwarf bamboo between harvesting and non-harvesting areas, and spatial distribution of deer was significantly biased to higher dwarf bamboo abundance areas, suggesting that the dwarf bamboo is an alternative food resource in non-harvesting areas where supplies of high-quality food were limited. Our results suggest that human harvesting pressure and residences shifted the spatial distribution of deer from the montane forests to subalpine/alpine zones, which may increase damage to vulnerable ecosystems due to severe foraging pressure.

3.
Animals (Basel) ; 14(15)2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39123685

RESUMO

Ungulates are terrestrial herbivores, basically adapted to running fast on the ground; tree-climbing behavior has been reported only in seven species, and five of them live in open habitats (Capra hircus, C. aegagrus, C. falconeri, C. cylindricornis, Oreotragus oreotragus). Tree-climbing behavior may also be evolved in ungulates inhabiting dense forests with abundant trees; however, this has rarely been reported in such species (Moschus leucogaster, M. moschiferus), probably due to the difficulty of observing in the wild. The numerous publicly available records in social networks hold potentially valuable information on the atypical behaviors of wild ungulates. Here, we explored the tree-climbing behavior of a forest-dwelling ungulate, the Formosan serow in Taiwan, a subtropical island, by extracting information from online social media platforms. We researched images and videos of Formosan serows through Facebook and YouTube and collected a total of 15 tree-climbing events. In these materials, Formosan serows climbed 10 tree species, including evergreen coniferous and broad-leaved trees, and a variety of parts, ranging in height from 0.6 to 4 m, and from branches of shrubs to trunks of tall trees. Tree-climbing behavior was recorded throughout Taiwan and from lowlands to subalpine zones, suggesting that tree climbing may be a common behavior in this species. Foraging while climbing trees was frequently observed (53.3%), suggesting that the purpose or benefit for climbing is to obtain additional food other than plants growing near the ground surface. In contrast to other tree-climbing ungulates, Formosan serows climbed trees not only in winter, but also in other seasons, when food is relatively abundant. This is the first scientific report of tree-climbing behavior in the Formosan serow that is typically a forest dweller.

4.
J Clin Microbiol ; 51(1): 328-30, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23135931

RESUMO

Whole-genome sequencing of non-H(2)S-producing Salmonella enterica serovar Typhimurium and S. enterica serovar Infantis isolates from poultry meat revealed a nonsense mutation in the phsA thiosulfate reductase gene and carriage of a CMY-2 ß-lactamase. The lack of production of H(2)S might lead to the incorrect identification of S. enterica isolates carrying antimicrobial resistance genes.


Assuntos
Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Salmonella enterica/genética , Animais , Genoma Bacteriano , Sulfeto de Hidrogênio/metabolismo , Japão , Salmonella enterica/enzimologia , Salmonella enterica/isolamento & purificação , Salmonella enterica/metabolismo , Análise de Sequência de DNA , Sulfurtransferases/genética , beta-Lactamases/genética
5.
Behav Processes ; 158: 228-233, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30585168

RESUMO

Observations of the flight response of ungulates are commonly used to test behavioral responses to predation risk. In gregarious ungulates with sexual body-size dimorphism such responses are likely to be stronger in situations where individuals have perceptions of less security as well as among more-sensitive individuals, such as female groups or female groups with offspring which are understood to use safety habitats more often than males do. However, little is known about these behaviors in solitary ungulates with little sexual dimorphism. Therefore, we examined the flight response to human presence and the habitat use of Japanese serow (Capricornis crispus), a solitary ungulate with little sexual dimorphism, in relation to its physical and social environments, based on direct observations conducted over approximately four years. Based on a total of 335 sightings, serows took flight less often when in steep terrain, in closed habitat, or in low-visibility seasons, and they selectively used steep-closed habitat. These findings suggest that steep slopes and low-visibility conditions provide the species with greater security, and that serows select safer habitats to decrease predation risk. There were no significant differences in the flight responses and habitat use of solitary males and solitary females; the absence of differences is likely related to the serow's habit of monogamy and its underdeveloped sexual dimorphism. Females with kids more frequently fled than other group types; this difference is thought to be linked to females' priority to secure the survival of their offspring. This result shows the key role of offspring presence in affecting flight response in the serow. Conversely, there were no differences in habitat use between females with kids and other group types; here, the absence of such differences may be associated with intra-sexual territoriality of the serow, since all types of territory holders (including females with kids) need to continuously use the entire home range to maintain a territory.


Assuntos
Artiodáctilos/fisiologia , Ecossistema , Meio Ambiente , Reação de Fuga/fisiologia , Meio Social , Animais , Feminino , Japão , Masculino , Comportamento Predatório , Estações do Ano , Caracteres Sexuais
6.
PLoS One ; 7(11): e50660, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23209804

RESUMO

We studied the molecular evolution of H gene in four prevalent Asian genotypes (D3, D5, D9, and H1) of measles virus (MeV). We estimated the evolutionary time scale of the gene by the bayesian Markov Chain Monte Carlo (MCMC) method. In addition, we predicted the changes in structure of H protein due to selective pressures. The phylogenetic tree showed that the first division of these genotypes occurred around 1931, and further division of each type in the 1960-1970s resulted in four genotypes. The rate of molecular evolution was relatively slow (5.57×10(-4) substitutions per site per year). Only two positively selected sites (F476L and Q575K) were identified in H protein, although these substitutions might not have imparted significant changes to the structure of the protein or the epitopes for phylactic antibodies. The results suggested that the prevalent Asian MeV genotypes were generated over approximately 30-40 years and H protein was well conserved.


Assuntos
Evolução Molecular , Hemaglutininas/genética , Vírus do Sarampo/genética , Proteínas Virais/genética , Genótipo
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