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1.
Anim. Reprod. (Online) ; 20(2): e20230026, 2023. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1452312

Resumo

Mitigation of the widely known threats to the world's biodiversity is difficult, despite the strategies and actions proposed by international agreements such as the United Nations Framework Convention on Climate Change (UNFCCC) and the Convention on Biological Diversity (CBD). Nevertheless, many scientists devote their time and effort to finding and implementing various solutions to the problem. One potential way forward that is gaining popularity involves the establishment of biobank programs aimed at preserving and storing germplasm from threatened species, and then using it to support the future viability and health of threatened populations. This involves developing and using assisted reproductive technologies to achieve their goals. Despite considerable advances in the effectiveness of reproductive technologies, differences between the reproductive behavior and physiology of widely differing taxonomic groups mean that this approach cannot be applied with equal success to many species. Moreover, evidence that epigenetic influences and developmental plasticity, whereby it is now understood that embryonic development, and subsequent health in later life, can be affected by peri-conceptional environmental conditions, is raising the possibility that cryopreservation methods themselves may have to be reviewed and revised when planning the biobanks. Here, I describe the benefits and problems associated with germplasm biobanking across various species, but also offer some realistic assessments of current progress and applications.(AU)


Assuntos
Criopreservação/veterinária , Antozoários/genética , Adaptação Fisiológica , Comportamento Reprodutivo , Biodiversidade
2.
Sci. agric ; 80: e20210142, 2023. ilus, tab, mapa, graf
Artigo em Inglês | VETINDEX | ID: biblio-1367270

Resumo

Adaptation to climate change is a strategy for crops to cope with the scenario of rising temperatures worldwide. In the case of Coffea arabica L., the use of agroforestry systems (AFS) with woody species is a promising practice to reduce excessive heat during the day. This study aimed to 1) evaluate air temperature changes that occur in an AFS of coffee and double alleys of rubber trees (Hevea brasiliensis Müell. Arg.) and 2) carry out an analysis of future warming scenarios by comparing the cultivation of Arabic coffee in full sun and in an AFS of double alleys of rubber trees. The microclimatic variables were measured between two rows of coffee trees at 1.0 m of height from June 2016 to June 2018. The results indicate that the AFS with double alleys of rubber trees spaced 16 m apart had an average temperature reduction from 1.4 to 2.5 °C from 10h00 to 16h00. The study also simulated temperature increases of 1.7, 2.6, 3.1, and 4.8 °C from 2018 to 2099, according to scenarios predicted by the Intergovernmental Panel on Climate Change (IPCC), and the impact in coffee production in Paraná State, Brazil. Using the climatic generator PGECLIMA_R, simulations suggest a progressive reduction of traditional areas suitable for open-grown coffee in the state. Production conditions can be maintained through the AFS, since the systems attenuate mean temperatures by 1-2 °C. We conclude that the AFS of coffee and rubber trees contribute to coffee crop adaptations to a future warmer environment.


Assuntos
Mudança Climática/estatística & dados numéricos , Adaptação Fisiológica , Hevea , Coffea/crescimento & desenvolvimento , Florestas
3.
Braz. j. biol ; 83: e248911, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339362

Resumo

Abstract The telencephalon refers to the most highly developed and anterior part of the forebrain, consisting mainly of the cerebral hemispheres. The study determined Neuroglobin (Ngb) and Hypoxia-inducible factor (HIF-1α) expression in the telencephalon of yak and cattle, and compare the expression and distribution pattern of Ngb and HIF-1α in the two animals. Immunohistochemistry (IHC), quantitative real-time Polymerase Chain Reaction (qRT-PCR), and Western blot (WB) were employed to investigate Ngb and Hif-1α expression in the telencephalon of yak and cattle. mRNA and protein expressions of Ngb and HIF-1α showed positive in different tissues of the yak and cattle telencephalon. Ngb expression in tissues of the yak recorded higher as compare to cattle while HIF-1α expression was found higher in cattle than yak. The HIF-1α expression in some tissues of yak telencephalon was consistent with the cattle. The results documented that HIF-1α may have a direct or indirect synergistic effect on Ngb expression in the yak telencephalon to improve hypoxia adaptation. It is suggested that yak may need more Ngb expression for adaptation, but the expression of HIF-1α seems to be down-regulated during long-term adaptation, and the specific causes of this phenomenon needs to be further verified.


Resumo O telencéfalo refere-se à parte anterior e mais desenvolvida do prosencéfalo, consistindo principalmente dos hemisférios cerebrais. O estudo determinou a expressão de neuroglobina (Ngb) e fator indutível por hipóxia (HIF-1α) no telencéfalo de iaques e bovinos e comparou a expressão e o padrão de distribuição de Ngb e HIF-1α nos dois animais. Imuno-histoquímica (IHC), reação em cadeia da polimerase quantitativa em tempo real (qRT-PCR) e Western blot (WB) foram empregados para investigar a expressão de Ngb e Hif-1α no telencéfalo de iaques e bovinos. As expressões de mRNA e proteínas de Ngb e HIF-1α mostraram-se positivas em diferentes tecidos do telencéfalo de iaque e bovino. A expressão de Ngb nos tecidos do iaque foi registrada mais alta em comparação com o gado, enquanto a expressão do HIF-1α foi encontrada mais alta no gado do que no iaque. A expressão de HIF-1α em alguns tecidos do telencéfalo de iaque foi consistente com o gado. Os resultados documentaram que o HIF-1α pode ter um efeito sinérgico direto ou indireto na expressão de Ngb no telencéfalo de iaque para melhorar a adaptação à hipóxia. É sugerido que o iaque pode precisar de mais expressão de Ngb para adaptação, mas a expressão de HIF-1α parece ser regulada para baixo durante a adaptação de longo prazo, e as causas específicas desse fenômeno precisam ser verificadas.


Assuntos
Animais , Telencéfalo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , RNA Mensageiro/genética , Bovinos , Adaptação Fisiológica , Neuroglobina
4.
Ciênc. rural (Online) ; 52(9): e20210271, 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1360355

Resumo

Stone fruit cultivation is an alternative income for rural producers in Brazil, mainly for the southern region. In the specific case of plums, the lack of varieties adapted to the climatic conditions of this region is an obstacle that the research needs to resolve. In this context, the work aimed to evaluate the behaviour of the Japanese plum genotype FLA3-3 from the breeding program of the University of Florida (USA) in Ponta Grossa, Parana, Brazil, during the years 2013, 2014 and 2015. The experimental design used was entirely random. Twenty plants of the genotype under study were used, each one being a repetition. The characteristics evaluated in the field were the flowering and fruiting cycles according to the plant phenology. Physical analyzes of the fruits were carried out in the laboratory: average mass (pulp and seeds) and diameter and chemical analyze: total soluble solids, total titratable acidity and ratio. The results confirm that the genotype is precocious and the fruit harvest begins in October / November. It is adapted to the climatic condition of the municipality of Ponta Grossa, Parana, Brazil, in addition to presenting fruits within the commercial standards sought by producers and consumers. It is a viable alternative for rural producers in the region.


O cultivo da fruta com caroço é uma alternativa de renda para os produtores rurais do Brasil, principalmente da região Sul. No caso específico das ameixas, a falta de variedades adaptadas às condições climáticas da região é um entrave que a pesquisa precisa superar. Nesse contexto, o trabalho teve como objetivo avaliar o comportamento do genótipo de ameixa japonesa FLA3-3 do programa de melhoramento da Universidade da Flórida (EUA) em Ponta Grossa, Paraná, Brasil, durante os anos de 2013, 2014 e 2015. O delineamento experimental usado foi inteiramente ao acaso. Foram utilizadas vinte plantas do genótipo em estudo, cada uma sendo uma repetição. As características avaliadas em campo foram os ciclos de floração e frutificação de acordo com a fenologia da planta. As análises físicas dos frutos foram realizadas em laboratório: massa média (polpa e sementes) e diâmetro e análise química: sólidos solúveis totais, acidez total titulável e proporção. Os resultados confirmam que o genótipo é precoce e a colheita dos frutos inicia-se em outubro / novembro. Está adaptado às condições climáticas do município de Ponta Grossa, Paraná, Brasil, além de apresentar frutas dentro dos padrões comerciais buscados por produtores e consumidores, sendo uma alternativa viável para os produtores rurais da região.


Assuntos
Adaptação Fisiológica/genética , Fenômenos Químicos , Prunus domestica/crescimento & desenvolvimento , Prunus domestica/genética , Prunus domestica/química
5.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 59: e181942, fev. 2022. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1363107

Resumo

The project is based on a test of a thoracic vibration vest prototype, adapted to equines by the Expector® vest's company, on healthy animals. Ten (10) equines were used in the project, male or female, adults, healthy, belonging to FMVZ-USP or private owners. Each animal went through two phases: A and B. Phase A consisted of the placement of the vest without turning on the vibrators, evaluating the animal's acceptability, facility, adaptation to the animal's body, and discomfort due to the vest's use. Phase B included the placement of the vest and turning on the vibrators, evaluating the animal's acceptability, reaction to the vibrators, and, if present, to which velocity/type of vibration, and the presence of adverse effects. Both phases were done three times on separate days. The behavioral parameters: "placement facility" and "adaptation to the animal's body" were observed. In phase B, the response to the vibration was classified from 0 to 5. The answer was evaluated on low and high intensities for the four vibration types. The heart rate (HR) and respiratory rate (RR) were also evaluated at the beginning and end of each repetition. The animals' HR was kept on normal, except for one animal on one day of the test. Concerning the RR, most animals presented moments of tachypnea. On the experiment's first day, 100% of grade Great to "facility of placement" and "adaptation to the animal's body" was obtained, but on days 2 and 3 this value dropped to 90% due to alterations in one animal's responses. Regarding vibration's responses, 77.3% were evaluated as no discomfort (grade 0), 17.1% little discomfort (grade 1), 3.3% medium discomfort (grade 2), 0.4% great discomfort (grade 3), 0.21% extreme discomfort (grade 4), and 1.6% non-acceptance of the vest (grade 5). Some possible changes on the prototype were also verified to be suggested to the manufacturer, such as the change of the buckle and the use of wireless control. Vest use appears promising for equine respiratory physiotherapy, considering the acceptability was good, and its efficiency on the expectoration of diseased animals must be tested.


O projeto consistiu no teste de um protótipo de colete de vibração torácica, adaptado aos equinos pela empresa do colete Expector®, em animais saudáveis. Foram utilizados 10 equinos, machos ou fêmeas, adultos, saudáveis, pertencentes à FMVZ-USP e a proprietários particulares. Cada animal passou por duas fases: A e B. A Fase A consistiu na colocação do colete sem ligar os vibradores, avaliando-se a aceitabilidade do animal; facilidade; adaptação ao corpo do animal e incômodo do mesmo à sua presença. Já a Fase B contava com a colocação do colete e funcionamento dos vibradores, avaliando-se a aceitabilidade do animal; reação aos vibradores e, se presente, a qual velocidade/tipo de vibração; presença de reações ou efeitos adversos. As duas fases foram realizadas em triplicata em dias separados. Foram observados os parâmetros comportamentais "facilidade de colocação" e "adaptação ao corpo do animal". Na fase B, a resposta à vibração foi classificada de 0 a 5. A resposta foi avaliada nas intensidades baixa e alta para os quatro diferentes tipos de vibração. Foram avaliadas também as frequências cardíaca (FC) e respiratória (FR) no início e final de cada repetição. A FC dos animais se manteve dentro do intervalo de normalidade, com exceção de um animal em um dia de avaliação. Em relação à FR, a maioria apresentou momentos de taquipneia. No primeiro dia de experimento obteve-se 100% de avaliação Ótima para "facilidade de colocação" e "adaptação ao corpo do animal", mas nos dias 2 e 3 esse valor caiu para 90% devido à alteração na resposta de um animal. Em relação à resposta à vibração, 77,3% das respostas foram avaliadas como nenhum incômodo (nota 0), 17,1% pouco incômodo (nota 1), 3,3% médio incômodo (nota 2), 0,4% muito incômodo (nota 3), 0,21% incômodo extremo (nota 4) e 1,6% não aceitação do colete (nota 5). Foram também verificadas algumas possíveis mudanças no protótipo a serem sugeridas ao fabricante, como mudança do tipo de fivela e uso de controle sem fio. A utilização do colete parece ser muito promissora para a fisioterapia respiratória em equinos, visto que a aceitabilidade foi muito boa, devendo-se agora realizar a avaliação de sua eficácia na expectoração de animais enfermos.(AU)


Assuntos
Animais , Adaptação Fisiológica , Modalidades de Fisioterapia/veterinária , Desenho de Equipamento , Taxa Respiratória/fisiologia , Frequência Cardíaca/fisiologia , Cavalos/fisiologia
6.
Iheringia, Sér. zool ; 1122022. mapas, ilus, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1380480

Resumo

A identidade de Psalidodon eigenmanniorum (Cope, 1894) e a possibilidade de se constituir em mais de uma espécie é testada através de análises da morfometria (19 medidas), dos caracteres merísticos (14 contagens) e do padrão de colorido de 705 exemplares provenientes dos sistemas dos rios Tramandaí/Mampituba, da laguna dos Patos e drenagem do baixo rio Uruguai. Foram diafanizados e corados 40 exemplares. Os dados morfométricos foram utilizados na Análise de Componentes Principais, Análise Discriminante, Morfometria Geométrica e Função Discriminante. As análises foram feitas considerando os sexos em separado dentro de cada sistema hidrográfico, bem como comparando as populações entre os sistemas hidrográficos e finalmente no conjunto de sistemas representando a área de ocorrência da espécie. A partir dos dados analisados não foram encontradas diferenças entre os sexos. Os resultados mostraram variação morfológica que não sustenta o reconhecimento de possíveis espécies crípticas. A variação encontrada nos dados merísticos, morfométricos e no padrão de colorido justifica a redescrição da espécie. Os resultados das comparações entre as populações indicaram variações nesses caracteres indicando que a espécie possui considerável plasticidade fenotípica.(AU)


The identity of Psalidodon eigenmanniorum (Cope, 1894) and the possibility of constituting more than one species is tested through analyzes of morphometry (19 measurements), meristic characters (14 counts) and the color pattern of 705 specimens from the Tramandaí/Mampituba, from the Patos lagoon and from the lower Uruguay River drainage. Forty specimens were cleared and stained. Morphometric data were used in Principal Component Analysis, Discriminant Analysis, Geometric Morphometry and Discriminant Function. The analysis was carried out considering the sexes separately within each hydrographic system, as well as comparing the populations between the hydrographic systems and finally in the set of systems representing the area of occurrence of the species. No differences were found between the sexes in the analyzed data. The results showed morphological variation that does not support the recognition of possible cryptic species. The variation found in meristic, morphometric and color pattern data justifies the redescription of the species. The species is described to the aforementioned drainages, and the results demonstrate its phenotypic plasticity.(AU)


Assuntos
Animais , Masculino , Feminino , Análise de Componente Principal/métodos , Characidae/classificação , Análise Discriminante , Variação Biológica da População
7.
Ciênc. rural (Online) ; 52(3): e20201079, 2022. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1339668

Resumo

Andropogon lateralis Nees is a native grass of southern Brazil and is one of the most frequent specie found in native grasslands. The species is widely distributed and has a high degree of phenotypic plasticity, which makes it highly adaptable to different edaphoclimatic conditions and management. This study aimed to evaluate the behavior of twelve ecotypes of A. lateralis, collected in different regions of the state of Rio Grande do Sul and cut to three different heights and subjected to two different defoliation frequencies. From September to February, the ecotypes were evaluated for total dry matter, leaf and stem yields. In addition, total, vegetative and reproductive tillers and plant height were measured. These characteristics are important for the selection of superior genotypes in terms of genetic variability and forage production. Total dry matter and leaf dry matter are characteristics with agronomic importance and they showed the highest correlation (r = 0.77), enabling an indirect selection for one of these characteristics. The natural selection of plants resulted in distinct structural, morphological and productive characteristics with heterogeneity that allows the selection and grouping according to the characteristics, ecotypes with superior agronomic characteristics can be included in breeding programs.


Andropogon lateralis Nees é uma gramínea nativa do sul do Brasil e uma das espécies mais frequentes na flora dos campos nativos da região. Possui ampla distribuição e alto grau de plasticidade fenotípica, tornando-o adaptável as condições edafoclimáticas e a práticas de desfolha. Este estudo teve como objetivo avaliar a dissimilaridade entre doze ecótipos de A. lateralis N., coletados em diferentes regiões do Rio Grande do Sul, submetidos a duas frequências de desfolha e três alturas de corte. No período de setembro a fevereiro, os ecótipos foram avaliados quanto à produção de matéria seca total, de lâminas foliares e de colmo. Além disso, foram medidos o número de perfilhos totais, vegetativos e reprodutivos e a altura das plantas. Essas características são importantes para a seleção de genótipos superiores em termos de variabilidade genética e produção de forragem. A matéria seca total e a matéria seca foliar são características com importância agronômica e apresentaram a maior correlação (r = 0,77), possibilitando uma seleção indireta para uma dessas características. A seleção natural das plantas resultou em características estruturais, morfológicas e produtivas distintas com uma heterogeneidade que permite a seleção e agrupamento de acordo com as características, ecótipos com características agronômicas superiores podem ser incluídos em programas de melhoramento.


Assuntos
Seleção Genética , Andropogon/crescimento & desenvolvimento , Andropogon/genética , Ecótipo
8.
Neotrop. ichthyol ; 19(4): e210054, 2021. tab, graf, mapas, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1351163

Resumo

Gymnogeophagus labiatus and G. lacustris have been long recognized as sister species exhibiting different ecological requirements. Gymnogeophagus labiatus occurs in rock bottom rivers in the hydrographic basins of Patos Lagoon (HBP) and Tramandaí River (HBT), while G. lacustris is exclusive from sand bottom coastal lagoons of the HBT. In this study, we used molecular markers, morphological measurements and data from nuptial male coloration to investigate the evolutionary relationship between these species in each hydrographic basin. We found, for all data sets, a closer relationship between G. labiatus and G. lacustris from the HBT than between G. labiatus populations from HBT and HBP. In particular, lip area had a large intraspecific plasticity, being uninformative to diagnose G. lacustris from G. labiatus. Molecular clock-based estimates suggest a recent divergence between species in the HBT (17,000 years ago), but not between G. labiatus from HBP and HBT (3.6 millions of years ago). Finally, we also found a divergent G. labiatus genetic lineage from the Camaquã River, in the HBP. These results show that the current taxonomy of G. labiatus and G. lacustris does not properly represent evolutionary lineages in these species.(AU)


Gymnogeophagus labiatus e G. lacustris vêm sendo consideradas espécies irmãs que possuem diferentes exigências ecológicas. Gymnogeophagus labiatus ocorre em rios de fundo de pedra nas bacias hidrográficas da Laguna dos Patos (HBP) e do rio Tramandaí (HBT), enquanto G. lacustris é exclusivo da HBT, ocorrendo em lagoas costeiras de fundo de arenoso. Nesse estudo, foram usados marcadores moleculares, medidas morfológicas e dados sobre a coloração nupcial em machos para investigar a relação evolutiva entre estas espécies em cada bacia hidrográfica. Para todos os conjuntos de dados foi observada uma relação mais próxima entre G. labiatus e G. lacustris da HBT do que entre as populações de G. labiatus da HBP e HBT. Em particular, a área do lábio teve uma grande plasticidade intraespecífica, não sendo informativa para diagnosticar G. lacustris de G. labiatus. Estimativas baseadas no relógio molecular sugeriram uma divergência recente entre as espécies da HBT (17.000 anos atrás), mas não entre as populações de G. labiatus da HBP e HBT (3,6 milhões de anos atrás). Finalmente, também foi encontrada uma linhagem genética de G. labiatus divergente no rio Camaquã, na HBP. Esses resultados mostram que a taxonomia atual de G. labiatus e G. lacustris não representa adequadamente as linhagens evolutivas nessas espécies.(AU)


Assuntos
Animais , Pesos e Medidas , DNA Mitocondrial/análise , Adaptação Fisiológica , Hidrografia , Ciclídeos
9.
Neotrop. ichthyol ; 19(4): e210054, 2021. tab, graf, mapas, ilus
Artigo em Inglês | VETINDEX | ID: vti-765892

Resumo

Gymnogeophagus labiatus and G. lacustris have been long recognized as sister species exhibiting different ecological requirements. Gymnogeophagus labiatus occurs in rock bottom rivers in the hydrographic basins of Patos Lagoon (HBP) and Tramandaí River (HBT), while G. lacustris is exclusive from sand bottom coastal lagoons of the HBT. In this study, we used molecular markers, morphological measurements and data from nuptial male coloration to investigate the evolutionary relationship between these species in each hydrographic basin. We found, for all data sets, a closer relationship between G. labiatus and G. lacustris from the HBT than between G. labiatus populations from HBT and HBP. In particular, lip area had a large intraspecific plasticity, being uninformative to diagnose G. lacustris from G. labiatus. Molecular clock-based estimates suggest a recent divergence between species in the HBT (17,000 years ago), but not between G. labiatus from HBP and HBT (3.6 millions of years ago). Finally, we also found a divergent G. labiatus genetic lineage from the Camaquã River, in the HBP. These results show that the current taxonomy of G. labiatus and G. lacustris does not properly represent evolutionary lineages in these species.(AU)


Gymnogeophagus labiatus e G. lacustris vêm sendo consideradas espécies irmãs que possuem diferentes exigências ecológicas. Gymnogeophagus labiatus ocorre em rios de fundo de pedra nas bacias hidrográficas da Laguna dos Patos (HBP) e do rio Tramandaí (HBT), enquanto G. lacustris é exclusivo da HBT, ocorrendo em lagoas costeiras de fundo de arenoso. Nesse estudo, foram usados marcadores moleculares, medidas morfológicas e dados sobre a coloração nupcial em machos para investigar a relação evolutiva entre estas espécies em cada bacia hidrográfica. Para todos os conjuntos de dados foi observada uma relação mais próxima entre G. labiatus e G. lacustris da HBT do que entre as populações de G. labiatus da HBP e HBT. Em particular, a área do lábio teve uma grande plasticidade intraespecífica, não sendo informativa para diagnosticar G. lacustris de G. labiatus. Estimativas baseadas no relógio molecular sugeriram uma divergência recente entre as espécies da HBT (17.000 anos atrás), mas não entre as populações de G. labiatus da HBP e HBT (3,6 milhões de anos atrás). Finalmente, também foi encontrada uma linhagem genética de G. labiatus divergente no rio Camaquã, na HBP. Esses resultados mostram que a taxonomia atual de G. labiatus e G. lacustris não representa adequadamente as linhagens evolutivas nessas espécies.(AU)


Assuntos
Animais , Pesos e Medidas , DNA Mitocondrial/análise , Adaptação Fisiológica , Hidrografia , Ciclídeos
10.
Ciênc. rural (Online) ; 51(11): 1-4, 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1480241

Resumo

This study evaluated the occupational exposure of workers to heat during manual harvesting of coffee. The case study was conducted between May to August. Occupational heat in coffee plantations was evaluated using the Wet Bulb Globe Temperature (WBGT) method and the metabolic rate. The WBGT was obtained using the TGD 400 thermal stress meter. The determined WBGT values ​​were compared to two standards: the Occupational Hygiene Standard (NHO) 06 and Regulatory Norm (NR) 09. For acclimatized workers, the exposure limit was not exceeded at any time during the evaluated period. Fornon-acclimatized workers, the exposure limit was not exceeded only in July.


O presente trabalhado teve como objetivo avaliar a exposição ocupacional de trabalhadores ao calor durante a colheita manual do cafeeiro. O estudo de caso foi desenvolvido entre os meses de maio a agosto. Avaliou-se o calor ocupacional em lavoura cafeeira através do método do Índice Bulbo Úmido Termômetro de Globo (IBUTG) e taxa metabólica. O IBUTG foi obtido utilizando o medidor de estresse térmico TGD 400. Os valores do IBUTG determinados foram comparados com duas normativas: Norma de Higiene Ocupacional (NHO) 06 e Norma Regulamentadora (NR) 09. Para trabalhadores aclimatizados o limite de exposição não foi superado em nenhum momento do período avaliado. Em relação aos trabalhadores não aclimatizados o limite de exposição não foi superado apenas em julho.


Assuntos
Humanos , Aclimatação/efeitos da radiação , Adaptação Fisiológica/efeitos da radiação , Café
11.
Ci. Rural ; 51(11): 1-4, 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-32067

Resumo

This study evaluated the occupational exposure of workers to heat during manual harvesting of coffee. The case study was conducted between May to August. Occupational heat in coffee plantations was evaluated using the Wet Bulb Globe Temperature (WBGT) method and the metabolic rate. The WBGT was obtained using the TGD 400 thermal stress meter. The determined WBGT values ​​were compared to two standards: the Occupational Hygiene Standard (NHO) 06 and Regulatory Norm (NR) 09. For acclimatized workers, the exposure limit was not exceeded at any time during the evaluated period. Fornon-acclimatized workers, the exposure limit was not exceeded only in July.(AU)


O presente trabalhado teve como objetivo avaliar a exposição ocupacional de trabalhadores ao calor durante a colheita manual do cafeeiro. O estudo de caso foi desenvolvido entre os meses de maio a agosto. Avaliou-se o calor ocupacional em lavoura cafeeira através do método do Índice Bulbo Úmido Termômetro de Globo (IBUTG) e taxa metabólica. O IBUTG foi obtido utilizando o medidor de estresse térmico TGD 400. Os valores do IBUTG determinados foram comparados com duas normativas: Norma de Higiene Ocupacional (NHO) 06 e Norma Regulamentadora (NR) 09. Para trabalhadores aclimatizados o limite de exposição não foi superado em nenhum momento do período avaliado. Em relação aos trabalhadores não aclimatizados o limite de exposição não foi superado apenas em julho.(AU)


Assuntos
Humanos , Aclimatação/efeitos da radiação , Adaptação Fisiológica/efeitos da radiação , Café
12.
Sci. agric ; 78(supl. 1): e20200292, 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1498003

Resumo

Intensification of drought in Mediterranean–type climates has limited seedling establishment. The knowledge of the ecology of selected species and its intraspecific variation to water stress at the seedling stage should be considered in order to overcome limitations. We investigated variations in growth, survival, and leaf–level physiology in four provenances of the endemic Cryptocarya alba (Mol.) during water stress and after re–watering. Seedlings were cultured in the nursery during 23 months and then subjected to two watering treatments based on soil water content (well–watered and water restriction, 0.38 and 0.17 cm3 cm−3, respectively) for 45 days. At the end of the watering treatments, seedling growth, above– and belowground biomass, survival, and leaf gas exchange were measured. Right after the watering treatments, the surviving seedlings were submitted to a recovery period of 21 days, in which all seedlings were re–watered at 0.38 cm3 cm−3 of soil water content and measured for leaf gas exchange. Provenances differed in growth and biomass allocation. Unlike growth and biomass, interaction between provenance and watering treatments was found for photosynthesis, stomatal conductance, transpiration, and water use efficiency of northern provenances, exhibiting the highest performance under water restriction. However, most variations observed occurred before the re–watering period and only a few occurred after this period. The four provenances under study exhibited similar photosynthesis and stomatal conductance after re–watering. Our study demonstrated phenotypic variation of C. alba and the capability of the species to withstand and recover from water stress.


Assuntos
Biomassa , Cryptocarya/crescimento & desenvolvimento , Cryptocarya/fisiologia , Desidratação , Irrigação Agrícola , Plasticidade Celular
13.
Sci. agric. ; 78(supl. 1): e20200292, 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-765605

Resumo

Intensification of drought in Mediterranean–type climates has limited seedling establishment. The knowledge of the ecology of selected species and its intraspecific variation to water stress at the seedling stage should be considered in order to overcome limitations. We investigated variations in growth, survival, and leaf–level physiology in four provenances of the endemic Cryptocarya alba (Mol.) during water stress and after re–watering. Seedlings were cultured in the nursery during 23 months and then subjected to two watering treatments based on soil water content (well–watered and water restriction, 0.38 and 0.17 cm3 cm−3, respectively) for 45 days. At the end of the watering treatments, seedling growth, aboveand belowground biomass, survival, and leaf gas exchange were measured. Right after the watering treatments, the surviving seedlings were submitted to a recovery period of 21 days, in which all seedlings were re–watered at 0.38 cm3 cm−3 of soil water content and measured for leaf gas exchange. Provenances differed in growth and biomass allocation. Unlike growth and biomass, interaction between provenance and watering treatments was found for photosynthesis, stomatal conductance, transpiration, and water use efficiency of northern provenances, exhibiting the highest performance under water restriction. However, most variations observed occurred before the re–watering period and only a few occurred after this period. The four provenances under study exhibited similar photosynthesis and stomatal conductance after re–watering. Our study demonstrated phenotypic variation of C. alba and the capability of the species to withstand and recover from water stress.(AU)


Assuntos
Cryptocarya/crescimento & desenvolvimento , Cryptocarya/fisiologia , Desidratação , Irrigação Agrícola , Biomassa , Plasticidade Celular
14.
J. Anim. Behav. Biometeorol. ; 09(03): 1-3, July 2021. ilus
Artigo em Inglês | VETINDEX | ID: vti-32990

Resumo

Meteorological variables are the main abiotic factors that directly influence reactions in rodent metabolism, activating the action of thermoregulatory mechanisms aimed at homeostasis and can involve several factors that work together to dissipate or conserve body heat. In this scenario, we aimed to address, synthetically, the main means that rodents have to adapt and survive faced with the thermoregulatory challenges posed by the environment in which they live. Among these processes, behavioral changes can occur in water and food intake, as well as voluntary displacement to environments offering greater thermal comfort. The autonomic processes involve innate mechanisms that act quickly to facilitate thermal exchange, such as sweating, respiratory evaporation, and changes in peripheral blood flow. Adaptation involves evolutionary processes that, in the long run, alter the morphophysiological characteristics of the epidermis and coat, in order to conserve or dissipate heat. Knowledge of the role of these processes in adaptive physiology is essential to understand how the thermal environment affects rodents and how deleterious effects are mitigated.(AU)


Assuntos
Animais , Camundongos , Adaptação Fisiológica/efeitos da radiação , Comportamento Animal/fisiologia , Roedores/metabolismo , Roedores/fisiologia , Mudança Climática
15.
J. Anim. Behav. Biometeorol ; 9(3): 1-3, July 2021. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1484355

Resumo

Meteorological variables are the main abiotic factors that directly influence reactions in rodent metabolism, activating the action of thermoregulatory mechanisms aimed at homeostasis and can involve several factors that work together to dissipate or conserve body heat. In this scenario, we aimed to address, synthetically, the main means that rodents have to adapt and survive faced with the thermoregulatory challenges posed by the environment in which they live. Among these processes, behavioral changes can occur in water and food intake, as well as voluntary displacement to environments offering greater thermal comfort. The autonomic processes involve innate mechanisms that act quickly to facilitate thermal exchange, such as sweating, respiratory evaporation, and changes in peripheral blood flow. Adaptation involves evolutionary processes that, in the long run, alter the morphophysiological characteristics of the epidermis and coat, in order to conserve or dissipate heat. Knowledge of the role of these processes in adaptive physiology is essential to understand how the thermal environment affects rodents and how deleterious effects are mitigated.


Assuntos
Animais , Camundongos , Adaptação Fisiológica/efeitos da radiação , Comportamento Animal/fisiologia , Roedores/fisiologia , Roedores/metabolismo , Mudança Climática
16.
Sci. agric ; 782021.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1497908

Resumo

ABSTRACT: Intensification of drought in Mediterraneantype climates has limited seedling establishment. The knowledge of the ecology of selected species and its intraspecific variation to water stress at the seedling stage should be considered in order to overcome limitations. We investigated variations in growth, survival, and leaflevel physiology in four provenances of the endemic Cryptocarya alba (Mol.) during water stress and after rewatering. Seedlings were cultured in the nursery during 23 months and then subjected to two watering treatments based on soil water content (wellwatered and water restriction, 0.38 and 0.17 cm3 cm3, respectively) for 45 days. At the end of the watering treatments, seedling growth, above and belowground biomass, survival, and leaf gas exchange were measured. Right after the watering treatments, the surviving seedlings were submitted to a recovery period of 21 days, in which all seedlings were rewatered at 0.38 cm3 cm3 of soil water content and measured for leaf gas exchange. Provenances differed in growth and biomass allocation. Unlike growth and biomass, interaction between provenance and watering treatments was found for photosynthesis, stomatal conductance, transpiration, and water use efficiency of northern provenances, exhibiting the highest performance under water restriction. However, most variations observed occurred before the rewatering period and only a few occurred after this period. The four provenances under study exhibited similar photosynthesis and stomatal conductance after rewatering. Our study demonstrated phenotypic variation of C. alba and the capability of the species to withstand and recover from water stress.

17.
Sci. agric ; 78(2): e20190095, 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1497932

Resumo

This study evaluated the leaf area index (LAI) recovery mechanisms and forage accumulation rates on the regrowth of different grass species subjected to different defoliation intensities. For that purpose, plots of Pennisetum clandestinum (kikuyugrass), Lolium multiflorum (annual ryegrass), and Avena strigosa (black oats) were defoliated from 20 to 80 % of their initial heights (25, 20, and 25 cm, respectively). At different increments in height, forage samples were collected to ground level and used to estimate tiller population density (TPD), leaf area per tiller (LA), and forage mass. From these data, we calculated the leaf area index (LAI), average leaf area index (aLAI), and average and instantaneous forage accumulation rate (FAR and IFAR, respectively). Data were plotted over time (days) to describe LAI recovery and forage accumulation rates. As the defoliation intensity increased, greater canopy heights were needed for pastures to achieve their maximum forage accumulation rates, which required longer regrowth intervals. The need for high tiller recruitment after defoliation, which delayed canopy LAI recovery, seemed to be one of the main cause. Thus, grazing management strategies that involve costly tiller recruitment could decrease both overall forage production and sward persistence over time. However, the plant ability to recover LAI after successive intense defoliations seems to be species-dependent and related to their phenotypic plasticity.


Assuntos
Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Pastagens/análise , Pastagens/métodos
18.
Sci. agric. ; 78(2): e20190095, 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-27992

Resumo

This study evaluated the leaf area index (LAI) recovery mechanisms and forage accumulation rates on the regrowth of different grass species subjected to different defoliation intensities. For that purpose, plots of Pennisetum clandestinum (kikuyugrass), Lolium multiflorum (annual ryegrass), and Avena strigosa (black oats) were defoliated from 20 to 80 % of their initial heights (25, 20, and 25 cm, respectively). At different increments in height, forage samples were collected to ground level and used to estimate tiller population density (TPD), leaf area per tiller (LA), and forage mass. From these data, we calculated the leaf area index (LAI), average leaf area index (aLAI), and average and instantaneous forage accumulation rate (FAR and IFAR, respectively). Data were plotted over time (days) to describe LAI recovery and forage accumulation rates. As the defoliation intensity increased, greater canopy heights were needed for pastures to achieve their maximum forage accumulation rates, which required longer regrowth intervals. The need for high tiller recruitment after defoliation, which delayed canopy LAI recovery, seemed to be one of the main cause. Thus, grazing management strategies that involve costly tiller recruitment could decrease both overall forage production and sward persistence over time. However, the plant ability to recover LAI after successive intense defoliations seems to be species-dependent and related to their phenotypic plasticity.(AU)


Assuntos
Pastagens/análise , Pastagens/métodos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia
19.
Sci. agric ; 77(3): e20180159, 2020. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1497853

Resumo

Pinus radiata D. Don is the most widely planted exotic species in Australia, Chile, New Zealand and Spain. In this study, growth and survival of P. radiata were compared in 30 open pollinated families grown under two contrasting watering regimes in nursery (well-watered cf. water-stress conditions) and planted on a drought-prone site with Mediterranean climate in central Chile. This study assessed phenotypic plasticity in growth and survival at nursery stage and two years after establishment in the field. Family plasticity at nursery stage was estimated by the angular phenotypic change index (APCI), while the relationship between nursery and field traits was estimated by genetic correlations (rg) and the Pearson coefficient of correlation (rxy). Families presented high plasticity in diameter, height, and survival at nursery stage. Out of 30 families, eight exhibited over 80 % survival in the well-watered treatment, but less than 20 % survival in the water-stress treatment. As expected, growth traits and survival were positively correlated (rg and rxy > 0.65) between both nursery environments. However, for growth, most genetic and phenotypic correlations between combinations of nursery treatments versus the field test were negative or not significant. As there was no detectable pattern of nursery–field correlations regarding to combinations of nursery treatments and test site, the need to include more stable families and genotypes to an appropriate developmental stage at nursery is discussed.


Assuntos
Pinus/crescimento & desenvolvimento , Secas
20.
Sci. agric. ; 77(3): e20180159, 2020. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-25047

Resumo

Pinus radiata D. Don is the most widely planted exotic species in Australia, Chile, New Zealand and Spain. In this study, growth and survival of P. radiata were compared in 30 open pollinated families grown under two contrasting watering regimes in nursery (well-watered cf. water-stress conditions) and planted on a drought-prone site with Mediterranean climate in central Chile. This study assessed phenotypic plasticity in growth and survival at nursery stage and two years after establishment in the field. Family plasticity at nursery stage was estimated by the angular phenotypic change index (APCI), while the relationship between nursery and field traits was estimated by genetic correlations (rg) and the Pearson coefficient of correlation (rxy). Families presented high plasticity in diameter, height, and survival at nursery stage. Out of 30 families, eight exhibited over 80 % survival in the well-watered treatment, but less than 20 % survival in the water-stress treatment. As expected, growth traits and survival were positively correlated (rg and rxy > 0.65) between both nursery environments. However, for growth, most genetic and phenotypic correlations between combinations of nursery treatments versus the field test were negative or not significant. As there was no detectable pattern of nursery–field correlations regarding to combinations of nursery treatments and test site, the need to include more stable families and genotypes to an appropriate developmental stage at nursery is discussed.(AU)


Assuntos
Pinus/crescimento & desenvolvimento , Secas
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