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1.
Braz. j. biol ; 832023.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469041

Resumo

Abstract In fisheries, the phenomenon known as fishing down food webs is supposed to be a consequence of overfishing, which would be reflected in a reduction in the trophic level of landings. In such scenarios, the resilience of carnivorous, top predator species is particularly affected, making these resources the first to be depleted. The Serra Spanish mackerel, Scomberomorus brasiliensis, exemplifies a predator resource historically targeted by artisanal fisheries on the Brazilian coast. The present work analyzes landings in three periods within a 50-year timescale on the Parana coast, Southern Brazil, aiming to evaluate whether historical production has supposedly declined. Simultaneously, the diet was analyzed to confirm carnivorous habits and evaluate the trophic level in this region. Surprisingly, the results show that from the 1970s to 2019 Serra Spanish mackerel production grew relatively to other resources, as well as in individual values. The trophic level was calculated as 4.238, similar to other Scomberomorus species, consisting of a case where landings increase over time, despite the high trophic level and large body size of the resource. The results agree with a recent global assessment that has demystified a necessary correlation between high trophic level and overexploitation, but possible factors acting on the present findings are discussed.


Resumo Na pesca, o fenômeno fishing down food webs, ou pescando teias tróficas abaixo, expressa a redução do nível trófico na composição das capturas, e tem origem tradicionalmente atribuída à sobrepesca. Sob intenso extrativismo, a resiliência das espécies carnívoras, predadoras de topo, é particularmente afetada, sendo seus estoques os primeiros a entrarem em depleção. A cavala, ou serra, ou sororoca, Scomberomorus brasiliensis, é exemplo de recurso predador historicamente alvo da pesca artesanal, de pequena escala, na costa brasileira. O presente trabalho analisa os valores de desembarque do recurso em três períodos ao longo de 50 anos na costa paranaense, sul do Brasil, com objetivo de avaliar se sua produção tem efetivamente diminuído. Ainda, estuda-se a dieta da espécie na região, para confirmar seus hábitos carnívoros e avaliar o nível trófico na região. Os resultados mostram que, surpreendentemente, dos anos 1970 para 2019 a produção de S. brasiliensis tem aumentado em valores absolutos, bem como relativamente à de outros recursos, em que pese o nível trófico 4,238, similar a outras espécies do gênero. Constata-se que a pesca da cavala na região de estudo constitui um caso de aumento nos desembarques a despeito de elevado nível trófico e grande tamanho corpóreo. Os resultados concordam com recente levantamento em nível mundial, que nega existir correlação necessária entre sobrepesca e nível trófico alto, mas fatores que podem explicar os resultados do presente trabalho são discutidos.

2.
Rev. Ciênc. Agrovet. (Online) ; 22(1): 103-108, mar. 2023. tab, ilus
Artigo em Português | VETINDEX | ID: biblio-1426366

Resumo

Aproveitando-se a ocorrência de um evento espontâneo de baixas temperaturas (<17oC) em experimento de campo de arroz irrigado, coincidente com a fase reprodutiva da cultura, foram avaliados a produtividade, a porcentagem de esterilidade de espiguetas e o número de panículas por metro quadrado. O experimento foi conduzido no sul de Santa Catarina, na safra 2019/2020, em delineamento de blocos ao acaso com trêsrepetições no sistema pré-germinado. Do total de genótipos que compunham o experimento, 13 foram selecionados para comporem a análise principal, de esterilidade.Baseado numa série de estudos anteriores para estresse por baixas e altas temperaturas, a hipótese era de que a linhagem SC 806 se destacaria como resiliente. De fato, a SC 806 apresentou níveis de esterilidade significativamente menores que as testemunhas comerciais SCS116 Satoru, SCS122 Miura e SC 790 (SCS125), ao mesmo tempo que foi competitiva com as mesmas no tocante à produtividade. Assim, a SC 806 foi validada como resiliente abaixastemperaturas, confirmando o bom desempenho verificado em experimentos anteriores, e com isso demonstrando ser promissora como linhagem candidata à lançamento na forma de variedade.(AU)


Concerning the occurrence of a spontaneous event of low temperatures (<17oC), in an irrigated rice field experiment, during the reproductive phase of the crop, yield was evaluated as well as percentage of grain sterility and number of panicles. The experiment was conducted in the southof Santa Catarina, in the 2019/2020 crop season, having been water-seeded in randomized blocks with threereplications. Of the total number of genotypes that made up the experiment, 13 were selected to make up the main analysis, of sterility. Based on a series of previous studies for stress due to low and high temperatures, the hypothesis was that the SC 806 line would stand out as resilient. Based on a series of previous studies for low and high temperature stress, the hypothesiswas that the SC 806 inbreed line would stand out as resilient. In fact, SC 806 showed significantly lower sterility levels than the commercial controls, SCS116 Satoru, SCS122 Miura and SC 790 (SCS125), while remaining competitive in terms of yield. Thus, SC 806 confirmed its resilience to low temperatures, what was a behavior showed in previous experiments, proving to be promising as a candidate for release as cultivar soon.(AU)


Assuntos
Oryza/genética , 24444 , Resposta ao Choque Térmico/genética , Brasil , Processos Climáticos
3.
J. Anim. Behav. Biometeorol ; 11(3): e2023027, 2023. graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1509957

Resumo

We aimed to assess the physiological and biophysical responses of Nellore bulls exposed to solar radiation in semiarid conditions throughout the day. Sixteen Nellore bulls were examined in Tibau city, Northeast Brazil (5°52ʹ South, 37°20ʹ West, and 37 m above sea level) over four nonconsecutive days, with data collection taking place at one-hour intervals between 7:00 am and 5:00 pm. Four animals were analyzed each day and kept exposed to the sun for the duration of the study. The average age of the animals was three years, and their average body weight was 650±32 kg. The meteorological station measured air temperature (°C), relative humidity (%), solar radiation (W.m-2 ), and black globe temperatures (°C) every minute, while a digital anemometer thermohygrometer measured wind speed (m.s-1 ) at the same time. Respiratory rate (breaths.min-1 ), expired air temperature (°C), rectal temperature (°C), and body surface temperature (°C) were measured as physiological variables. Biophysical equations were used to estimate the sensible and latent heat transfer mechanisms (W.m-2 ). The air temperature ranged from 28.5 to 32.5°C, and direct solar radiation was between 21 and 891 W.m-². Between 11:00 am and 1:00 pm, the study observed heat gain through longwave radiation, which reached an average of 250 W.m-2 , with a significant increase (P < 0.05) in respiratory rate and body surface temperature during this time. Convection was significant in heat dissipation, particularly when the wind speed was increased from 11:00 am. However, latent heat loss mechanisms were more effective in losing excess body heat under total sun exposure, despite the positive effect of convection. The study findings showed that Nellore bulls maintained their body temperature within a narrow range even when exposed to high solar radiation, thus demonstrating the efficiency of physiological and biophysical mechanisms during times of greater thermal challenge.(AU)


Assuntos
Animais , Masculino , Bovinos/fisiologia , Exposição à Radiação/análise , Transtornos de Estresse por Calor
4.
Braz. j. biol ; 83: 1-7, 2023. map, graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468825

Resumo

In fisheries, the phenomenon known as fishing down food webs is supposed to be a consequence of overfishing, which would be reflected in a reduction in the trophic level of landings. In such scenarios, the resilience of carnivorous, top predator species is particularly affected, making these resources the first to be depleted. The Serra Spanish mackerel, Scomberomorus brasiliensis, exemplifies a predator resource historically targeted by artisanal fisheries on the Brazilian coast. The present work analyzes landings in three periods within a 50-year timescale on the Parana coast, Southern Brazil, aiming to evaluate whether historical production has supposedly declined. Simultaneously, the diet was analyzed to confirm carnivorous habits and evaluate the trophic level in this region. Surprisingly, the results show that from the 1970's to 2019 Serra Spanish mackerel production grew relatively to other resources, as well as in individual values. The trophic level was calculated as 4.238, similar to other Scomberomorus species, consisting of a case where landings increase over time, despite the high trophic level and large body size of the resource. The results agree with a recent global assessment that has demystified a necessary correlation between high trophic level and overexploitation, but possible factors acting on the present findings are discussed.


Na pesca, o fenômeno fishing down food webs, ou 'pescando teias tróficas abaixo', expressa a redução do nível trófico na composição das capturas, e tem origem tradicionalmente atribuída à sobrepesca. Sob intenso extrativismo, a resiliência das espécies carnívoras, predadoras de topo, é particularmente afetada, sendo seus estoques os primeiros a entrarem em depleção. A cavala, ou serra, ou sororoca, Scomberomorus brasiliensis, é exemplo de recurso predador historicamente alvo da pesca artesanal, de pequena escala, na costa brasileira. O presente trabalho analisa os valores de desembarque do recurso em três períodos ao longo de 50 anos na costa paranaense, sul do Brasil, com objetivo de avaliar se sua produção tem efetivamente diminuído. Ainda, estuda-se a dieta da espécie na região, para confirmar seus hábitos carnívoros e avaliar o nível trófico na região. Os resultados mostram que, surpreendentemente, dos anos 1970 para 2019 a produção de S. brasiliensis tem aumentado em valores absolutos, bem como relativamente à de outros recursos, em que pese o nível trófico 4,238, similar a outras espécies do gênero. Constata-se que a pesca da cavala na região de estudo constitui um caso de aumento nos desembarques a despeito de elevado nível trófico e grande tamanho corpóreo. Os resultados concordam com recente levantamento em nível mundial, que nega existir correlação necessária entre sobrepesca e nível trófico alto, mas fatores que podem explicar os resultados do presente trabalho são discutidos.


Assuntos
Animais , Cadeia Alimentar , Dieta , Equilíbrio Ecológico/análise , Pesqueiros
5.
Braz. j. biol ; 83: e246180, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278550

Resumo

Abstract In fisheries, the phenomenon known as fishing down food webs is supposed to be a consequence of overfishing, which would be reflected in a reduction in the trophic level of landings. In such scenarios, the resilience of carnivorous, top predator species is particularly affected, making these resources the first to be depleted. The Serra Spanish mackerel, Scomberomorus brasiliensis, exemplifies a predator resource historically targeted by artisanal fisheries on the Brazilian coast. The present work analyzes landings in three periods within a 50-year timescale on the Parana coast, Southern Brazil, aiming to evaluate whether historical production has supposedly declined. Simultaneously, the diet was analyzed to confirm carnivorous habits and evaluate the trophic level in this region. Surprisingly, the results show that from the 1970's to 2019 Serra Spanish mackerel production grew relatively to other resources, as well as in individual values. The trophic level was calculated as 4.238, similar to other Scomberomorus species, consisting of a case where landings increase over time, despite the high trophic level and large body size of the resource. The results agree with a recent global assessment that has demystified a necessary correlation between high trophic level and overexploitation, but possible factors acting on the present findings are discussed.


Resumo Na pesca, o fenômeno fishing down food webs, ou 'pescando teias tróficas abaixo', expressa a redução do nível trófico na composição das capturas, e tem origem tradicionalmente atribuída à sobrepesca. Sob intenso extrativismo, a resiliência das espécies carnívoras, predadoras de topo, é particularmente afetada, sendo seus estoques os primeiros a entrarem em depleção. A cavala, ou serra, ou sororoca, Scomberomorus brasiliensis, é exemplo de recurso predador historicamente alvo da pesca artesanal, de pequena escala, na costa brasileira. O presente trabalho analisa os valores de desembarque do recurso em três períodos ao longo de 50 anos na costa paranaense, sul do Brasil, com objetivo de avaliar se sua produção tem efetivamente diminuído. Ainda, estuda-se a dieta da espécie na região, para confirmar seus hábitos carnívoros e avaliar o nível trófico na região. Os resultados mostram que, surpreendentemente, dos anos 1970 para 2019 a produção de S. brasiliensis tem aumentado em valores absolutos, bem como relativamente à de outros recursos, em que pese o nível trófico 4,238, similar a outras espécies do gênero. Constata-se que a pesca da cavala na região de estudo constitui um caso de aumento nos desembarques a despeito de elevado nível trófico e grande tamanho corpóreo. Os resultados concordam com recente levantamento em nível mundial, que nega existir correlação necessária entre sobrepesca e nível trófico alto, mas fatores que podem explicar os resultados do presente trabalho são discutidos.


Assuntos
Animais , Perciformes , Pesqueiros , Brasil , Conservação dos Recursos Naturais , Cadeia Alimentar
6.
Braz. J. Biol. ; 83: 1-7, 2023. mapas, graf, tab
Artigo em Inglês | VETINDEX | ID: vti-765402

Resumo

In fisheries, the phenomenon known as fishing down food webs is supposed to be a consequence of overfishing, which would be reflected in a reduction in the trophic level of landings. In such scenarios, the resilience of carnivorous, top predator species is particularly affected, making these resources the first to be depleted. The Serra Spanish mackerel, Scomberomorus brasiliensis, exemplifies a predator resource historically targeted by artisanal fisheries on the Brazilian coast. The present work analyzes landings in three periods within a 50-year timescale on the Parana coast, Southern Brazil, aiming to evaluate whether historical production has supposedly declined. Simultaneously, the diet was analyzed to confirm carnivorous habits and evaluate the trophic level in this region. Surprisingly, the results show that from the 1970's to 2019 Serra Spanish mackerel production grew relatively to other resources, as well as in individual values. The trophic level was calculated as 4.238, similar to other Scomberomorus species, consisting of a case where landings increase over time, despite the high trophic level and large body size of the resource. The results agree with a recent global assessment that has demystified a necessary correlation between high trophic level and overexploitation, but possible factors acting on the present findings are discussed.(AU)


Na pesca, o fenômeno fishing down food webs, ou 'pescando teias tróficas abaixo', expressa a redução do nível trófico na composição das capturas, e tem origem tradicionalmente atribuída à sobrepesca. Sob intenso extrativismo, a resiliência das espécies carnívoras, predadoras de topo, é particularmente afetada, sendo seus estoques os primeiros a entrarem em depleção. A cavala, ou serra, ou sororoca, Scomberomorus brasiliensis, é exemplo de recurso predador historicamente alvo da pesca artesanal, de pequena escala, na costa brasileira. O presente trabalho analisa os valores de desembarque do recurso em três períodos ao longo de 50 anos na costa paranaense, sul do Brasil, com objetivo de avaliar se sua produção tem efetivamente diminuído. Ainda, estuda-se a dieta da espécie na região, para confirmar seus hábitos carnívoros e avaliar o nível trófico na região. Os resultados mostram que, surpreendentemente, dos anos 1970 para 2019 a produção de S. brasiliensis tem aumentado em valores absolutos, bem como relativamente à de outros recursos, em que pese o nível trófico 4,238, similar a outras espécies do gênero. Constata-se que a pesca da cavala na região de estudo constitui um caso de aumento nos desembarques a despeito de elevado nível trófico e grande tamanho corpóreo. Os resultados concordam com recente levantamento em nível mundial, que nega existir correlação necessária entre sobrepesca e nível trófico alto, mas fatores que podem explicar os resultados do presente trabalho são discutidos.(AU)


Assuntos
Animais , Pesqueiros , Cadeia Alimentar , Equilíbrio Ecológico/análise , Dieta
7.
J. venom. anim. toxins incl. trop. dis ; 29: e20230002, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1448596

Resumo

Abstract This overview aimed to describe the situation of healthcare access in sub-Saharan Africa, excluding South Africa, during the COVID-19 pandemic. A PubMed® search from March 31, 2020, to August 15, 2022, selected 116 articles. Healthcare access and consequences of COVID-19 were assessed based on comparisons with months before its onset or an identical season in previous years. A general reduction of healthcare delivery, associated with the decline of care quality, and closure of many specialty services were reported. The impact was heterogeneous in space and time, with an increase in urban areas at the beginning of the pandemic (March-June 2020). The return to normalcy was gradual from the 3rd quarter of 2020 until the end of 2021. The impact of COVID-19 on the health system and its use was attributed to (a) conjunctural factors resulting from government actions to mitigate the spread of the epidemic (containment, transportation restrictions, closures of businesses, and places of entertainment or worship); (b) structural factors related to the disruption of public and private facilities and institutions, in particular, the health system; and (c) individual factors linked to the increase in costs, impoverishment of the population, and fear of contamination or stigmatization, which discouraged patients from going to health centers. They have caused considerable socio-economic damage. Several studies emphasized some adaptability of the healthcare offer and resilience of the healthcare system, despite its unpreparedness, which explained a return to normal activities as early as 2022 while the COVID-19 epidemic persisted. There appears to be a strong disproportion between the moderate incidence and severity of COVID-19 in sub-Saharan Africa, and the dramatic impact on healthcare access. Several articles make recommendations for lowering the socioeconomic consequences of future epidemics to ensure better management of health issues.


Assuntos
Humanos , Pandemias , COVID-19 , Acessibilidade aos Serviços de Saúde , África Subsaariana
8.
Braz. j. biol ; 82: e260420, 2022. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1394098

Resumo

Silicon (Si) is a beneficial element that can mitigate effects of water stress on photosynthetic metabolism and plant growth. Thus, the aimed was to evaluate the effect of Si in mitigating the stressful effect of water deficit and flooding in Eugenia myrcianthes Nied. seedlings. The seedlings received three silicon doses (0, 2, and 4 mmol) and were subjected to two water regimes (I - continuous irrigation and S - water fluctuation, characterized as water stress obtained by two cycles of water regimes: irrigation suspension and flooding). Each cycle was ended when the seedlings had a photosynthetic rate close to zero (P0) when the stressful irrigation condition was normalized until the photosynthetic rate reached the values of the control seedlings (REC). The evaluations were carried out in five periods: T0 - initial seedling condition; 1st and 2nd P0; and 1st and 2nd REC. The E. myrcianthes seedlings reached P0 at 22 and 50 days under water deficit and flooding, respectively. Water stress caused damage to photochemical activities in photosystem II. E. myrcianthes is a species sensitive to water stress, but capable of adjusting to water fluctuation, and the application of 2 mmol Si contributed to the regulation of gas exchange, photochemical yields, and growth of this species at the deficit and flooding phases. We emphasize that E. myrcianthes seedlings have potential for resilience due to physiological plasticity, regardless of the silicon application.


O silício (Si) é um elemento benéfico que pode mitigar os efeitos do estresse hídrico sobre o metabolismo fotossintético e crescimento das plantas. Assim, objetivou-se avaliar o potencial do Si na mitigação do efeito estressante do déficit hídrico e alagamento em mudas de Eugenia myrcianthes Nied. As mudas receberam aplicação de três doses de silício: 0, 2 e 4 mmol e foram submetidas a dois regimes hídricos: (I) - irrigação contínua e (E) flutuação hídrica, caracterizada como estresse hídrico obtido por dois ciclos de regimes hídricos: suspensão da irrigação e alagamento. Cada ciclo foi encerrado quando as mudas apresentaram taxa fotossintética próxima de zero (F0), momento que a condição de irrigação estressante foi normalizada até que a taxa fotossintética alcançasse os valores das mudas controle (REC). As avaliações foram realizadas em cinco períodos: T0 - condição inicial das mudas; 1ª e 2ª F0; 1ª e 2ª REC. As mudas de E. myrcianthes atingiram F0 aos 22 e 50 dias sob déficit hídrico e alagamento, respectivamente. O estresse hídrico promoveu danos nas atividades fotoquímicas no fotossistema II. E. myrcianthes é uma espécie sensível ao estresse hídrico, mas capaz de se ajustar à flutuação hídrica e a aplicação de 2 mmol de Si contribuiu na regulação das trocas gasosas, rendimentos fotoquímicos e crescimento dessa espécie na fase de déficit e alagamento. Ressaltamos que mudas de E. myrcianthes apresentam potencial de resiliência por plasticidade fisiológica independente da aplicação de silício.


Assuntos
Silício , Desidratação , Eugenia/crescimento & desenvolvimento
9.
Ciênc. rural (Online) ; 52(3): e20201096, 2022. tab
Artigo em Inglês | VETINDEX | ID: biblio-1339671

Resumo

In dry regions worldwide, providing feed for ruminants has been a great challenge, with a need to use plants which contribute to the resilience of production systems. Maniçoba is seen as a potential forage resource in the Brazilian semiarid, being used as hay or silage to feed ruminants. This review summarized results regarding forage production of maniçoba, in addition to dry matter (DM) intake, productive performance, and quality of animal products obtained providing maniçoba based diets, when compared to diets composed by other roughages for goats and sheep. Considering the evaluated studies, the average yield of maniçoba varied from 367 to 1,592 kg DM ha-¹, enhancing the forage yield by increasing plant fertilization and planting density. Diets based on maniçoba promoted similar or higher intake of DM and productive performance for goats and sheep, when compared to diets comprising other forage resources. The quality of animal products was also similar to the ones obtained with diets based on traditional roughages, such as Tifton 85 hay or spineless cactus. Therefore, maniçoba allows a forage production that may contribute to ruminant production systems in semiarid environment and promote productive performance and animal product quality compatible to the ones provided by traditional forage plants.


Nas regiões secas mundiais, fornecer alimentos para ruminantes tem sido um grande desafio, havendo necessidade de utilizar plantas que contribuam para a resiliência dos sistemas de produção. A maniçoba é vista como um potencial recurso forrageiro no semiárido brasileiro, sendo utilizada como feno ou silagem para alimentação de ruminantes. O objetivo desta revisão foi sumarizar os resultados quanto à produção de forragem da maniçoba, além do consumo de matéria seca (MS), desempenho produtivo e qualidade dos produtos de origem animal obtidos com dietas à base de maniçoba, quando comparados com dietas compostas por outros volumosos para caprinos e ovinos. Considerando os estudos avaliados, a produtividade média da maniçoba variou de 367 a 1.592 kg de MS ha-¹, com aumento da produção de forragem pela maior fertilização da planta e densidade de plantio. As dietas à base de maniçoba promoveram resultados semelhantes ou superiores para ingestão de matéria seca e desempenho produtivo de caprinos e ovinos, quando comparadas às dietas compostas por outros recursos forrageiros. A qualidade dos produtos de origem animal também foi semelhante às proporcionadas por dietas à base de volumosos tradicionais, como feno Tifton 85 ou palma-forrageira. Portanto, a maniçoba apresenta produção de forragem que pode contribuir com os sistemas de produção de ruminantes em ambiente semiárido, e promover desempenho produtivo e qualidade dos produtos de origem animal compatíveis com as proporcionadas pelas forrageiras tradicionais.


Assuntos
Animais , Ruminantes/crescimento & desenvolvimento , Manihot , Dieta/veterinária
10.
Acta sci., Biol. sci ; 44: e52771, mar. 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1368075

Resumo

The existence of environmental disturbances is an important facilitating factor to the establishment of biological invasions (BI). Biological invasions are considered the second biggest threat to the planet's biodiversity, behind only anthropic actions such as deforestation and habitat fragmentation. Thus, all environments are subjected to biological invasions, including Conservation Units (CU). The objective of the work was to evaluate the impacts of the exotic invasive Ricinus communis L. on the native biota of the Morro do Urubu Environmental Protection Area, Aracaju, Sergipe State, Brazil. Plots were allocated in places invaded by exotic invasive and in non-invaded places. Within the sample units, the number of individuals of each species present was counted. With these data, the statistics of the present study were performed. In the plots plotted on the non-invaded sites, 28 species were found. In the plots plotted on the invaded sites, only three species were sampled, among them the exotic invader studied, which showed to be the most abundant taxon in the area. In total, 75 individuals were counted in the invaded sites, of which 72 were from R. communis. In the non-invaded sites, 210 individuals. The average number of species was statistically higher in the plots where the exotic invader was removed, while from the second reading and remained until the eighth reading, the same happened for the average number of individuals. The results of this study showed the impacts caused by invasive exotic Ricinus communis on the composition, richness, diversity and resilience of an invaded Atlantic Forest area.(AU)


Assuntos
Ricinus , Produtos Biológicos , Ecossistema , Biodiversidade , Biota , Conservação dos Recursos Naturais
11.
Acta sci., Biol. sci ; 44: e52779, mar. 2022. ilus, graf
Artigo em Inglês | VETINDEX | ID: biblio-1367956

Resumo

Salinity is a major abiotic stress that adversely affects several physiological and biochemical aspects of plants. Antioxidants can be used as a potential remediation mechanism to promote plant resilience. Therefore, the objective of the present study was to evaluate increasing doses of the antioxidant lycopene on the germination and initial growth of common bean seedlings under conditions of salt stress. Seeds were treated with the following lycopene concentrations: 0.018; 0.036; 0.072; 0.144; and 0.288 g L-1 and two controls (negative and positive) and evaluated under two growth conditions (without and with salt stress) for physiological quality and pigment content. Data were analyzed by completely randomized design, in 2 x 7 factorial (two growth conditions, with paper towel moistened with water or salt solution x seven treatments, including five lycopene doses and two controls), in four replicates of 50 seeds by concentration. With the results of the analysis of variance, growth conditions (without and with salt stress) were compared by the Tukey test (5%), and the effects of lycopene doses were analyzed by polynomial regression. Lycopene promoted tolerance of bean seeds to salt stress and had a positive influence on the attenuation of salt harmful effects to the initial growth of seedlings, mainly at the doses of 0.072 g L-1 and 0.144 g L-1.(AU)


Assuntos
Estresse Fisiológico , Phaseolus/fisiologia , Phaseolus/química , Licopeno , Estresse Salino , Salinidade , Antioxidantes
12.
Bol. Inst. Pesca (Impr.) ; 48: e679, 2022. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1400879

Resumo

The chemoprotection of "buriti" Mauritia flexuosa (inclusion in diet: 0-control group; 1.25; 2.50; 5.00; and 10.00% W/W) to Litopenaeus vannamei postlarvae (PL) exposed to ammonia or nitrite was in-vestigated. Analyzed variables include antioxidant (ACAP) and oxidative damage (TBARS) responses and levels of total carotenoids. The results indicated that there was no significant difference (p >0.05) in zootechnical variables between diets. The PL carotenoid content (R2 = 0.86), ACAP (R2 = 0.78), and TBARS (R2 = 0.91) showed a dose-dependent relationship with the inclusion levels of "buriti"(p <0.05). After 43 days, juvenile shrimps were exposed for 96 h to ammonia (0.48 mg NH3-N L-1) or nitrite (40 mg NO3 L-1). Higher scavenging activity against peroxyl radicals was observed in PL fed with 2.50 and 5.00% of "buriti" (ammonia exposure), or 5.00 and 10.00% (nitrite exposure) of "buriti" inclusion. Content of reduced glutathione was higher in shrimps exposed to ammonia and fed with 10.00% of "buriti". Lipid peroxidation levels were lower in shrimps exposed to ammonia or nitrite and previously fed with inclusion higher than 2.50% of "buriti". The increased scavenging activity and lower lipid peroxidation in ammonia or nitrite-exposed organisms and previously supplemented with "buriti" point to a hormetic response that increases the resilience of L. vannamei to cope with nitroge-nous compounds, pointing to the use of this fruit as a chemoprotectant agent.


Foi avaliada a quimioproteção do "buriti" Mauritia flexuosa (inclusão na dieta: 0-grupo controle; 1,25; 2,50; 5,00; e 10,00% P/P) em pós-larvas (PL) de Litopenaeus vannamei expostas à amônia ou nitrito. As variáveis analisadas incluíram respostas antioxidantes (ACAP) e de dano oxidativo (TBARS) e te-ores de carotenoides totais. Os resultados obtidos indicaram que não houve diferenças significativas (p >0,05) nas variáveis zootécnicas entre as dietas. O conteúdo de carotenoides nas PL (R2 = 0,86), ACAP (R2 = 0,78), e TBARS (R2 = 0,91) mostraram um relação dose-resposta com os níveis de inclusão de "buriti"(p <0,05). Após 43 días, os camarões juvenis foram expostos por 96 h à amônia (0,48 mg NH3-N L-1) ou à nitrito (40 mg NO3 L-1). Uma elevada capacidade antioxidante contra radicais peroxil foi observada em PL alimentadas 2,50 e 5,00% de "buriti" (exposição à amônia), ou 5,00 e 10,00 % (exposição à nitrito) de inclusão de "buriti". O conteúdo de glutationa reduzida foi superior em camarões expostos à amônia e alimentados com 10.00% de "buriti". Os níveis de peroxidação lipídica foram inferiores em camarões expostos à amônia ou nitrito e previamente alimentados com níveis de inclusão de buriti superiores a 2,50%. O aumento de capacidade antioxidante e redução da peroxidação lipídica nos organismos expostos à amônia ou nitrito que previamente foram suplementados com "buriti" sugere uma resposta hormética, incrementando a resiliência de L. vannamei frente a compos-tos nitrogenados, recomendando o uso deste fruto como agente quimioprotetor.


Assuntos
Animais , Arecaceae , Penaeidae/crescimento & desenvolvimento , Alimento Funcional , Amônia/antagonistas & inibidores , Nitritos/antagonistas & inibidores , Quimioprevenção/veterinária , Ração Animal
13.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1461037

Resumo

Salinity is a major abiotic stress that adversely affects several physiological and biochemical aspects of plants. Antioxidants can be used as a potential remediation mechanism to promote plant resilience. Therefore, the objective of the present study was to evaluate increasing doses of the antioxidant lycopene on the germination and initial growth of common bean seedlings under conditions of salt stress. Seeds were treated with the following lycopene concentrations: 0.018; 0.036; 0.072; 0.144; and 0.288 g L-1 and two controls (negative and positive) and evaluated under two growth conditions (without and with salt stress) for physiological quality and pigment content. Data were analyzed by completely randomized design, in 2 x 7 factorial (two growth conditions, with paper towel moistened with water or salt solution x seven treatments, including five lycopene doses and two controls), in four replicates of 50 seeds by concentration. With the results of the analysis of variance, growth conditions (without and with salt stress) were compared by the Tukey test (5%), and the effects of lycopene doses were analyzed by polynomial regression. Lycopene promoted tolerance of bean seeds to salt stress and had a positive influence on the attenuation of salt harmful effects to the initial growth of seedlings, mainly at the doses of 0.072 g L-1 and 0.144 g L-1.


Salinity is a major abiotic stress that adversely affects several physiological and biochemical aspects of plants. Antioxidants can be used as a potential remediation mechanism to promote plant resilience. Therefore, the objective of the present study was to evaluate increasing doses of the antioxidant lycopene on the germination and initial growth of common bean seedlings under conditions of salt stress. Seeds were treated with the following lycopene concentrations: 0.018; 0.036; 0.072; 0.144; and 0.288 g L-1 and two controls (negative and positive) and evaluated under two growth conditions (without and with salt stress) for physiological quality and pigment content. Data were analyzed by completely randomized design, in 2 x 7 factorial (two growth conditions, with paper towel moistened with water or salt solution x seven treatments, including five lycopene doses and two controls), in four replicates of 50 seeds by concentration. With the results of the analysis of variance, growth conditions (without and with salt stress) were compared by the Tukey test (5%), and the effects of lycopene doses were analyzed by polynomial regression. Lycopene promoted tolerance of bean seeds to salt stress and had a positive influence on the attenuation of salt harmful effects to the initial growth of seedlings, mainly at the doses of 0.072 g L-1 and 0.144 g L-1.

14.
Acta sci., Biol. sci ; 42: e48620, fev. 2020. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460911

Resumo

The effect of management (ecological and conventional) on functional groups of microorganisms of soil in agroecosystems with different resilience scores reported to climate variability in Anolaima, Colombia was evaluated. Were found clustering associated with management and cellulolytic bacteria and fungi abundances. No differences found in diversity of phosphate solubilizing or nitrogen-fixing microorganisms, related to management. The diversity of microbial functional groups was affected by the climatic condition of sampling season. Management was relevant in relationships between resilience scores to climate variability and cellulolytic microorganisms; in ecological agroecosystems, biodiversity knowledge, agroecological main structure, and the participation of farmers in organizations were important.


Assuntos
Análise do Solo , Biologia do Solo/análise , Fosfatos , Microbiologia do Solo , Fixação de Nitrogênio
15.
Acta Sci. Biol. Sci. ; 42: e48620, fev. 2020. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-745726

Resumo

The effect of management (ecological and conventional) on functional groups of microorganisms of soil in agroecosystems with different resilience scores reported to climate variability in Anolaima, Colombia was evaluated. Were found clustering associated with management and cellulolytic bacteria and fungi abundances. No differences found in diversity of phosphate solubilizing or nitrogen-fixing microorganisms, related to management. The diversity of microbial functional groups was affected by the climatic condition of sampling season. Management was relevant in relationships between resilience scores to climate variability and cellulolytic microorganisms; in ecological agroecosystems, biodiversity knowledge, agroecological main structure, and the participation of farmers in organizations were important.(AU)


Assuntos
Microbiologia do Solo , Análise do Solo , Biologia do Solo/análise , Fosfatos , Fixação de Nitrogênio
16.
Acta amaz. ; 50(2): 124-132, abr.-jun. 2020. mapas, tab
Artigo em Inglês | VETINDEX | ID: vti-28918

Resumo

Shade-tolerant forest species are among the most susceptible to habitat loss in agricultural mosaics, where a variety of croplands is connected to forests at different levels of anthropogenic disturbance. We aimed to evaluate the community similarity of shade-tolerant species among different land use types across agricultural mosaics with different levels of disturbance. The study was conducted in three municipalities in southern and southeastern Pará state, in eastern Amazonia. A multiple-community similarity measure based on the Horn similarity index was used to compare land use types and assess the resilience of shade-tolerant species towards forest loss and disturbance at the landscape level. High shade-tolerant species similarity was found between mature forest fragments that underwent different levels of disturbance in all three agricultural mosaics, but secondary forests had lower similarity with mature forest in the most fragmented and altered mosaic. Shade-tolerant species showed very low density in croplands, but the same group of species seemed to colonize agricultural fields of annual crops and clean pasture, as they showed high community similarity. Another group of species was present in invaded pastures, probably due to the effects of time since land abandonment after woody species colonization. Mixed tree plantations were more similar to mature and secondary forests than other types of croplands. Shade-tolerant species similarity was higher among land use types inserted in agricultural landscapes that maintained conserved forest fragments. Our results suggest that the conservation of mature forests and landscape connectivity are crucial to the maintenance of shade-tolerant species in agricultural mosaics.(AU)


As espécies florestais tolerantes à sombra estão entre as mais suscetíveis à perda de habitat em mosaicos agrícolas, onde uma variedade de terras agrícolas está conectada a florestas em diferentes níveis de distúrbio antropogênico. Este trabalho teve como objetivo avaliar a similaridade da comunidade de espécies tolerantes à sombra entre diferentes tipos de uso da terra em mosaicos agrícolas com diferentes níveis de perturbação. O estudo foi realizado em três municípios localizados no sul e sudeste do estado do Pará. Uma medida de similaridade de comunidade múltipla baseada no índice de similaridade de Horn foi usada para comparar diferentes tipos de uso da terra em três diferentes mosaicos. Alta similaridade de espécies tolerantes à sombra foi encontrada entre fragmentos de florestas maduras que sofreram diferentes níveis de distúrbio nos três mosaicos agrícolas, mas florestas secundárias apresentaram menor semelhança com a floresta madura no mosaico mais fragmentado e alterado. As espécies tolerantes à sombra apresentaram densidades muito baixas nas terras agrícolas, no entanto, o mesmo grupo de espécies tolerantes à sombra parece colonizar os cultivos anuais e as pastagens limpas. Por outro lado, outro grupo de espécies esteve presente em pastagens invadidas. As plantações mistas de árvores foram mais semelhantes às florestas maduras e secundárias do que outros tipos de terras agrícolas. Nossos resultados sugerem que a conservação de florestas maduras e da conectividade da paisagem são cruciais para a manutenção de espécies tolerantes à sombra em mosaicos agrícolas.(AU)


Assuntos
Conservação dos Recursos Naturais , Pastagens , Ecossistema
17.
Ci. Rural ; 50(11): e20191019, 2020.
Artigo em Inglês | VETINDEX | ID: vti-29577

Resumo

This paper reflects on the controversy between agroecology and modern conventional agriculture. As a counter-paradigm, agroecology criticizes and resists advances in agricultural sciences, including biotechnology. But does not offer concrete answers to the challenge of increasing food production in the world in a sustentably way. It is a view that denies the importance of modern agriculture to solve the problems of scarcity and food security and does not recognize the potential of genetic modification to decisively to promote sustainable agriculture, accelerating the overcoming of the so-called chemical reductionist paradigm. The principal argument is that agroecology, despite being an area of knowledge that can contribute to recovering natural resources and helping natures resilience, is not an alternative to modern conventional agriculture and has been trying to prevent advances in genetic engineering, a fundamental area for sustainability and for the low carbon agriculture. In the end, based on the importance of the controversy in the History of Science, presents the reasons why agroecology does not fulfill the requirements to be an agricultural science.(AU)


Este artigo reflete sobre a controvérsia entre a agroecologia e a agricultura convencional moderna. Como um contra-paradigma, a agroecologia critica e resiste aos avanços nas ciências agrícolas, incluindo a biotecnologia. Mas não oferece respostas concretas ao desafio de aumentar a produção de alimentos no mundo de maneira sustentável. É uma visão que nega a importância da agricultura moderna para resolver os problemas de escassez e segurança alimentar e não reconhece o potencial da modificação genética para promover decisivamente a agricultura sustentável, acelerando a superação do chamado paradigma reducionista químico. O principal argumento é que a agroecologia, apesar de ser uma área do conhecimento que pode contribuir para recuperar os recursos naturais e ajudar a resiliência da natureza, não é uma alternativa à agricultura convencional moderna e vem tentando impedir avanços na engenharia genética, uma área fundamental para a sustentabilidade e para a agricultura de baixo carbono. Por fim, com base na importância da controvérsia na História da Ciência, explora as razões pelas quais a agroecologia não preenche os requisitos para ser uma ciência agrária.(AU)


Assuntos
Agricultura Sustentável , Biotecnologia , Ciências Agrárias , Exploração de Recursos Naturais
18.
J. Anim. Behav. Biometeorol. ; 08(04): 266-275, Oct. 2020. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-763899

Resumo

A study was conducted to compare the adaptive ability of three indigenous goat breeds (Osmanabadi,Malabari, and Salem Black) to heat stress. The primary objective of the study was to assess the thermo-tolerant ability of these breeds to heat stress based on the changes in their blood biochemical response and aldosterone concentration. Thirty six-ten months to one year old female goats were randomly allocated into six groups of six animals each as OCON (n=6; Osmanabadi control), OHS (n=6; Osmanabadi heat stress), MCON (n=6; Malabari control), MHS (n=6; Malabari heat stress), SCON (n=6; Salem Black control) and SHS (n=6; Salem Black heat stress). The OCON, MCON, and SCON animals were maintained in the shed while OHS, MHS, and SHS animals were exposed to summer heat stress between 10:00 h to 16:00 h. All the animals had access to ad-libitum feed and water. The duration of the study was 45 days. The results indicated that breed differences (P < 0.01) were established for the levels of plasma glucose, total protein, albumin, and globulin. However, heat stress treatment did not influence these variables. Further, heat stress significantly increased (P < 0.05) plasma cholesterol only in the MHS group. Besides, albumin/globulin (A/G) ratio, plasma urea, and plasma urea nitrogen (PUN) did not show any significant variation both among and within the breed for the treatment. However, plasma triglyceride was significantly lower (P < 0.05) in both OHS and SHS groups as compared to their respective control groups. Further, aspartate aminotransferase (AST) showed significant variation for the breed (P < 0.05) as well as treatment (P < 0.05) with a higher concentration in the OHS group. Among the breeds, heat stress induced lower (P < 0.05) plasma aldosterone was established only in the MHS group. Thus, it can be concluded from the results that the Malabari breed which was well known for its survival in a harsh environment in its native tract could not adapt well to the [...](AU)


Assuntos
Animais , Feminino , Ruminantes/sangue , Análise Química do Sangue/veterinária , Resposta ao Choque Térmico/efeitos da radiação , Aldosterona/análise
19.
J. Anim. Behav. Biometeorol ; 8(4): 266-275, Oct. 2020. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1484328

Resumo

A study was conducted to compare the adaptive ability of three indigenous goat breeds (Osmanabadi,Malabari, and Salem Black) to heat stress. The primary objective of the study was to assess the thermo-tolerant ability of these breeds to heat stress based on the changes in their blood biochemical response and aldosterone concentration. Thirty six-ten months to one year old female goats were randomly allocated into six groups of six animals each as OCON (n=6; Osmanabadi control), OHS (n=6; Osmanabadi heat stress), MCON (n=6; Malabari control), MHS (n=6; Malabari heat stress), SCON (n=6; Salem Black control) and SHS (n=6; Salem Black heat stress). The OCON, MCON, and SCON animals were maintained in the shed while OHS, MHS, and SHS animals were exposed to summer heat stress between 10:00 h to 16:00 h. All the animals had access to ad-libitum feed and water. The duration of the study was 45 days. The results indicated that breed differences (P < 0.01) were established for the levels of plasma glucose, total protein, albumin, and globulin. However, heat stress treatment did not influence these variables. Further, heat stress significantly increased (P < 0.05) plasma cholesterol only in the MHS group. Besides, albumin/globulin (A/G) ratio, plasma urea, and plasma urea nitrogen (PUN) did not show any significant variation both among and within the breed for the treatment. However, plasma triglyceride was significantly lower (P < 0.05) in both OHS and SHS groups as compared to their respective control groups. Further, aspartate aminotransferase (AST) showed significant variation for the breed (P < 0.05) as well as treatment (P < 0.05) with a higher concentration in the OHS group. Among the breeds, heat stress induced lower (P < 0.05) plasma aldosterone was established only in the MHS group. Thus, it can be concluded from the results that the Malabari breed which was well known for its survival in a harsh environment in its native tract could not adapt well to the [...]


Assuntos
Feminino , Animais , Aldosterona/análise , Análise Química do Sangue/veterinária , Resposta ao Choque Térmico/efeitos da radiação , Ruminantes/sangue
20.
J. Anim. Behav. Biometeorol. ; 8(1): 25-31, Jan. 2020. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-25819

Resumo

The study was conducted to establish the differences in the expression pattern of different cell surface toll-likereceptors (TLRs) between indigenous Osmanabadi and Salem Black goats subjected to summer season induced heat stress. The primary objective of the study is to assess the thermotolerance ability of these two breeds based on maintaining the immune status during exposure to heat stress. The results indicated that the expression of TLR1, TLR4, TLR5, TLR6, and TLR10 genes in both the breeds showed different expression pattern. The expression pattern of all these genes did not differed between the control (OC) and heat stress (OHS) group in Osmanabadi breed but significantly higher (P<0.05) expression of these genes were reported in heat stress group (SBHS) as compared to control group (SBC) in Salem Black breed. However, the striking difference was established in the expression pattern of TLR2 between these breeds. The TLR expression was significantly higher in heat stress group of Osmanabadi breed. But TLR2 did not express in Salem Back breed. The higher expression of most of the cell surface TLRs in the SBHS group as compared to OHS group indicates the superior resilient capacity of Salem Black goats to maintain immune status even during exposure to adverse environmental condition. Further, these TLRs could serve as indicators to reflect better thermo-tolerance of Salem Black breed over Osmanabadi breed.(AU)


Assuntos
Animais , Cabras/genética , Transtornos de Estresse por Calor/genética , Transtornos de Estresse por Calor/veterinária , Receptores Toll-Like , Termotolerância/genética
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