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1.
BMC Ecol Evol ; 24(1): 5, 2024 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-38184553

RESUMO

BACKGROUND: The diversity and population genetic structure of many species have been shaped by historical and contemporary climatic changes. For the species of the South American Altiplano, the historical climatic changes are mainly related to the wet events of great magnitude and regional influence that occurred during the Pleistocene climatic oscillations (PCOs). In contrast, contemporary climate changes are associated with events of lesser magnitude and local influence related to intensifications of the South American Summer Monsoon (SASM). Although multiple studies have analyzed the effect of PCOs on the genetic patterns of highland aquatic species, little is known about the impact of contemporary climate changes in recent evolutionary history. Therefore, in this study, we investigated the change in population structure and connectivity using nuclear and mitochondrial markers throughout the distribution range of Heleobia ascotanensis, a freshwater Cochliopidae endemic to the Ascotán Saltpan. In addition, using geometric morphometric analyses, we evaluated the concomitance of genetic divergence and morphological differentiation. RESULTS: The mitochondrial sequence analysis results revealed the presence of highly divergent co-distributed and geographically nested haplotypes. This pattern reflects an extension in the distribution of groups that previously would have differentiated allopatrically. These changes in distribution would have covered the entire saltpan and would be associated with the large-scale wet events of the PCOs. On the other hand, the microsatellite results defined five spatially isolated populations, separated primarily by geographic barriers. Contemporary gene flow analyses suggest that post-PCO, climatic events that would have connected all populations did not occur. The morphometric analyses results indicate that there is significant morphological differentiation in the populations that are more isolated and that present the greatest genetic divergence. CONCLUSIONS: The contemporary population structure and morphological variation of H. ascotanensis mainly reflect the post-PCO climatic influence. Although both markers exhibit high genetic structuring, the microsatellite and morphology results show the preponderant influence of fragmentation in recent evolutionary history. The contemporary genetic pattern shows that in species that have limited dispersal capabilities, genetic discontinuities can appear rapidly, erasing signs of historical connectivity.


Assuntos
Evolução Biológica , Mudança Climática , Animais , Chile , Água Doce , Caramujos
2.
J Equine Vet Sci ; 131: 104928, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37730075

RESUMO

Equine asthma is an airway disease that affects a large number of horses annually leading to considerable economic losses in the horse industry. Despite advances in research in this area, there is still a lack of information on its etiology and molecular characterization in pasture associated asthma. The objective of the current study was to characterize the inflammatory disease of lower airways in horses maintained on pasture through cytologic and immunologic profile during the summer in a tropical environment by analysis of the gene expression of Th1 cytokines (IFN- λ, IL-8), Th2 cytokines (IL-4 and IL-5), and pro-inflammatory cytokines (IL-1, TNF-α) in the bronchoalveolar lavage (BAL) fluid in healthy and asthma horses on pasture. A group 39 of clinically healthy horses maintained on native pasture and supplemented with concentrate was evaluated by BAL analyzed for differential cellular count and assigned into a control and an asthma group. The gene expression of pro-inflammatory cytokines was analyzed in the BAL by reverse time PCR (RT-PCR) (IL-1α (alpha), IL-4, IL-5, IL-8, TNF-α alpha and IFN-λ), using ß-actin as housekeeping gene. Higher gene expression of IL-1, IL-4, IL-5, IL-8, IFN-λ in the BAL of asthma horses was found. Current results indicate an increase in Th2, characterizing an allergic inflammatory reaction due to the significant increase in IL-5 in asthmatic horses (10.3 ± 1.13), when compared to the values ​​obtained in normal horses (3.27 ± 0.46). The only down regulated cytokine in the asthma group was TNF-α, suggesting a chronic antigenic reaction.


Assuntos
Asma , Doenças dos Cavalos , Cavalos , Animais , Fator de Necrose Tumoral alfa/genética , Interleucina-8/genética , Interleucina-4/genética , Interleucina-5 , Asma/genética , Asma/veterinária , Doenças dos Cavalos/genética
3.
PNAS Nexus ; 2(6): pgad175, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37287708

RESUMO

Records of element ratios obtained from the Maldives Inner Sea sediments provide a detailed view on how the Indian Monsoon System has varied at high-resolution time scales. Here, we present records from International Ocean Discovery Program (IODP) Site U1471 based on a refined chronology through the past 550,000 years. The record's high resolution and a proper approach to set the chronology allowed us to reconstruct changes in the Indian Monsoon System on a scale of anomalies and to verify their relationships with established records from the East Asian Monsoon System. On the basis of Fe/sum and Fe/Si records, it can be demonstrated that the Asia continental aridity tracks sea-level changes, while the intensity of winter monsoon winds responds to changes in Northern Hemisphere summer insolation. Furthermore, the anomalies of continental aridity and intensity of winter monsoon winds at millennial-scale events exhibit power in the precession band, nearly in antiphase with Northern Hemisphere summer insolation. These observations indicate that the insolation drove the anomalies in the Indian Summer Monsoon. The good correspondence between our record and the East Asian monsoon anomaly records suggests the occurrence of anomalous widespread arid events in Asia.

4.
Rev. Ciênc. Agrovet. (Online) ; 22(1): 133-145, mar. 2023. tab, graf, mapas
Artigo em Inglês | VETINDEX | ID: biblio-1426446

RESUMO

Globalization, population change, and rural-to-urban movement are the main causes of the enormous issues faced by rural communities. Every growing nation, including the Kurdistan Region of Iraq (KRI), has a sizable proportion of rural farmers among its populace. This study was done in the Sulaimani Governorate, which was divided into six main districts namely; Garmian, Penjwin, Halabja, Chamchamal, Sharazur, and Raniya, and aimed to compare the groundwater level with summer crop water demand. The weighted Sum Method (WSM) and a Normalized Difference Vegetation Index map (NDVI) were used to analyze and illustrate the current water demand status for summer crops. The study employed a participatory research design, utilizing a purposive sampling method to select 60representative farmers, 25key decision-makers, representatives from Non-Governmental Organizations (NGOs), and experts in the field of water management. Data was collected through the use of focus group discussions (FGDs) and Key Informant Interviews (KIIs) to gather information from the selected participants. This study is innovative in its attempt to establish a correlation between the yield of summer crops and the availability of groundwater. As a conclusion for this study, the results suggest that thelevel of groundwater playsa significant role in determining the production of summer crops. Additionally, the sustainable development of various regions within the Sulaimani Governorate is influenced by a complex interplay of environmental, economic, andsocial factors. Future work will be focus on doing a detail research regarding time series for ground water level (GWL) vs.crop production vs.NDVI.(AU)


A globalização, a transição demográfica e o êxodo rural são as principais problemas enfrentados pelas comunidades rurais. Cada nação em crescimento, incluindo a região do Curdistão do Sul no Iraque, ainda mantém uma proporção considerável de agricultores em propriedades rurais. Este estudo foi feito na província de Sulaimani, que foi dividida em seis distritos principais, a saber; Garmian, Penjwin, Halabja, Chamchamal, Sharazur e Raniya, e teve como objetivo comparar o nível das águas subterrâneas com a demanda de água das culturas de verão existentes. O Método da Soma Ponderada e o índice de vegetação de diferença normalizada (IVDN) foram usados para analisar e ilustrar o estado atual da demanda de água para as culturas de verão da região. Oestudo empregou um projetode pesquisa participativa, utilizando um método de amostragem intencional para selecionar 60 agricultores representativos, 25 tomadores de decisão, representantes de organizações não governamentais e especialistas na área de gestão de recursoshídricos. Os dados foram coletados por meio do uso de discussões de grupos focais e entrevistas com pessoas-chave para coletar informações dos participantes selecionados. Este estudo é inovador em sua tentativa de estabelecer uma correlação entre o rendimento das culturas de verão e a disponibilidade de água subterrânea. Como conclusão para este estudo, os resultados sugerem que o nível das águas subterrâneas desempenha um papel significativo na determinação da produção de culturas de verão. Além disso, odesenvolvimento sustentável de várias regiões da província de Sulaimani é influenciado por uma complexa interação de fatores ambientais, econômicos e sociais. O trabalho futuro será focado em fazer uma pesquisa detalhada sobre séries temporais para nível de água subterrânea vs. produção agrícola vs. IVDN.(AU)


Assuntos
Produtos Agrícolas , Conservação dos Recursos Hídricos/métodos , População Rural , Estações do Ano , Agricultura Sustentável
5.
Arq. bras. med. vet. zootec. (Online) ; 74(4): 603-610, July-Aug. 2022. tab
Artigo em Inglês | VETINDEX | ID: biblio-1393908

RESUMO

The present study was conducted to investigate the effect of season and housing system on hematochemical attributes of rabbits in Southern Punjab, Pakistan. Adult healthy rabbits (n=30) were divided into two groups of equal size (n=15). Group I was housed in a modern cage system and group II in traditional colony system for a period of one year. Blood samples of rabbits from both groups were collected in the summer and the winter seasons and analyzed for various hematochemical attributes. Hematochemical attributes including red blood cell (RBC) count, hematocrit (HCT), mean corpuscular volume (MCV), total white blood cell (WBC) count, mixed cells (MID), granulocytes (GRA), glucose and alanine aminotransferase (ALT) were lowered significantly (P<0.05) in the summer in relation to the winter, while mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), creatinine, and cholesterol level were significantly (P<0.05) higher during the summer season. Biochemical attributes as cholesterol, triglycerides and globulin were significantly (P<0.05) lower in the caged rabbits. In conclusion, the summer season caused a significant decrease in most of the hematochemical attributes whereas housing system did not affect most of the hematochemical attributes of the rabbits under the climatic conditions of Southern Punjab, Pakistan.


O presente estudo foi realizado para investigar o efeito da estação do ano e do sistema de alojamento nos atributos hemato-químicos dos coelhos no Sul do Punjab, Paquistão. Os coelhos adultos saudáveis (n=30) foram divididos em dois grupos de mesmo tamanho (n=15). O grupo I foi alojado em um moderno sistema de gaiolas e o grupo II em sistema de colônia tradicional por um período de um ano. Amostras de sangue de coelhos em ambos os grupos foram coletadas no verão e no inverno e analisadas para vários atributos hemato-químicos. Os atributos hemato-químicos, incluindo contagem de hemácias, hematócrito (HCT), volume corpuscular médio (MCV), contagem total de leucócitos, células mistas (MID), granulócitos (GRA), glicose e alanina aminotransferase (ALT) foram significativamente reduzidos (P<0.05) no verão comparado ao inverno, enquanto a hemoglobina corpuscular média (HGM), a concentração média de hemoglobina corpuscular (HGM), creatinina e nível de colesterol foram significativamente (P<0,05) mais altos durante a estação do verão. Atributos bioquímicos como colesterol, triglicerídeos e globulina foram significativamente (P<0,05) mais baixos em coelhos engaiolados. Em conclusão, a estação do verão causou uma diminuição significativa na maioria dos atributos hemato-químicos, enquanto o sistema de alojamento não afetou a maioria dos atributos hemato-químicos dos coelhos sob as condições climáticas do Punjab do Sul, Paquistão.


Assuntos
Animais , Coelhos , Paquistão , Coelhos , Estações do Ano , Hematologia , Habitação
6.
J Anim Sci ; 100(9)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35737943

RESUMO

The objective of the present study was to evaluate the productive performance and grazing behavior of 25 primiparous and 44 multiparous Holstein cows in a pasture-based automatic milking system (AMS) while experiencing heat stress (defined as a temperature-humidity index [THI] ≥ 68). Productive traits were analyzed according to the THI from days 0, -1, -2, and -3 in relation to the milking day, and grazing behaviors (expressed as the percentage of daily observation time) were related to the average THI only on the day of observation. Milk yield was not associated with the THI on day 0, but a significant linear relationship was found with the THI on the three previous days, decreasing approximately 0.18 kg (primiparous) and 0.40 kg (multiparous) per THI unit increment. In contrast, for multiparous cows only, the milking frequency was positively associated with the THI on the day of evaluation but not on the previous days, increasing 0.01 milking/THI unit increments. Additionally, for each unit of THI increment, cows spent 0.14% more time standing, whereas they exhibited a decrease in grazing, lying, and ruminating behaviors time by 0.30%, 0.04%, and 0.70%, respectively, for both parities. In conclusion, milk loss was related to heat stress conditions from the previous days, but not milking frequency, which increased with the THI of the same milking day. Lower grazing, lying, and ruminating activities and greater standing behavior were observed due to heat stress.


In higher temperature conditions, dairy cows under pasture-based automatic milking systems may experience heat stress, affecting their health and productive performance. In the present study, the relationships between heat stress, measured by the temperature­humidity index (THI), productive traits, and grazing behaviors were evaluated. Cows exhibited an increase in milking frequency and their time standing, decreasing the time grazing, lying, and ruminating as the THI increased on the same day. Additionally, cows had decreased milk production when the THI increased in the previous days. Understanding how cows adjust their grazing behavior to handle changes in the environment allows for the development of management strategies designed to improve animal welfare.


Assuntos
Doenças dos Bovinos , Transtornos de Estresse por Calor , Animais , Bovinos , Indústria de Laticínios , Feminino , Transtornos de Estresse por Calor/veterinária , Resposta ao Choque Térmico , Lactação , Leite
7.
Rev. argent. microbiol ; 54(1): 51-60, mar. 2022. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1407166

RESUMO

Resumen La inclusión de cultivos de cobertura invernales (CCI) en un sistema de siembra directa (SD) en reemplazo del barbecho constituye una alternativa promisoria para mejorar la salud del suelo y contribuir a la sustentabilidad ambiental de los sistemas agrícolas. Esta revisión ofrece un panorama integral de los efectos sobre el microbioma del suelo que tiene la introducción de CCI en rotación con cultivos de verano en sistemas de SD vs. el barbecho desnudo. Se realizó una búsqueda sistemática de la literatura que reporta los efectos de los CCI sobre los parámetros de abundancia, actividad y diversidad microbiana del suelo. Combinando 7 criterios de búsqueda se seleccionaron y analizaron 22 trabajos. El conjunto de resultados de esos trabajos muestra que la actividad enzimática del suelo se ve favorecida con la inclusión de CCI en la rotación, principalmente si estos se componen de leguminosas y mezclas de especies. Más de la mitad de esos trabajos reportan una mayor biomasa microbiana con CCI que con barbecho. Además, se advierte que los efectos de los CCI sobre los parámetros microbianos son independientes de la duración de los ensayos. Sin embargo, aún se necesitan más investigaciones básicas que permitan reducir la heterogeneidad entre estudios y comprender las complejas interacciones que ocurren entre los CCI y el microbioma del suelo.


Abstract The inclusion of winter cover crops (WCC) in no-till (NT) systems in replacement of bare fallow is a promising alternative to improve soil health and consequently, contribute to environmental sustainability of agricultural systems. This review provides a comprehensive evaluation of the effects of the use of WCC in rotation with summer cash crops under NT systems on the soil microbiome versus bare fallows. A systematic literature search was conducted to evaluate the impact of WCC on microbial parameters indicative of abundance, activity and diversity. Twenty-two papers were selected based on seven combined criteria. The results of this review show that enzyme activities in soil are enhanced with the inclusion of WCC in the rotation, particularly those that include legumes and mix of species. ln general, more than half of the analyzed papers report higher microbial biomass in soils with WCC than in bare fallow. Interestingly, the effects of WCC on microbial parameters are independent of the duration of the experiments. However, more basic research is necessary to reduce the heterogeneity of the studies and to better understand the complexity of the interactions between WCC and the soil microbiome.

8.
Rev Argent Microbiol ; 54(1): 57-70, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-33941408

RESUMO

The inclusion of winter cover crops (WCC) in no-till (NT) systems in replacement of bare fallow is a promising alternative to improve soil health and consequently, contribute to environmental sustainability of agricultural systems. This review provides a comprehensive evaluation of the effects of the use of WCC in rotation with summer cash crops under NT systems on the soil microbiome versus bare fallows. A systematic literature search was conducted to evaluate the impact of WCC on microbial parameters indicative of abundance, activity and diversity. Twenty-two papers were selected based on seven combined criteria. The results of this review show that enzyme activities in soil are enhanced with the inclusion of WCC in the rotation, particularly those that include legumes and mix of species. In general, more than half of the analyzed papers report higher microbial biomass in soils with WCC than in bare fallow. Interestingly, the effects of WCC on microbial parameters are independent of the duration of the experiments. However, more basic research is necessary to reduce the heterogeneity of the studies and to better understand the complexity of the interactions between WCC and the soil microbiome.


Assuntos
Microbiota , Solo , Agricultura/métodos , Produtos Agrícolas , Microbiologia do Solo
9.
Curr Issues Mol Biol ; 43(3): 2253-2265, 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34940132

RESUMO

The use of α-tocopherol during in vitro maturation (IVM) is an alternative to minimize the adverse effects of heat stress on oocyte competence. However, α-tocopherol is diluted in ethanol, which can induce oocyte parthenogenetic activation (PA). This study aimed to evaluate the role of ethanol concentration on PA and the effect of α-tocopherol supplementation during IVM on the developmental competence and the expression of key genes in blastocysts derived from summer-collected oocytes. All in vitro embryo production was conducted at 5% O2, 5% CO2 at 38.5 °C. Experiment 1: oocytes were cultured with or without 0.05% ethanol. As positive PA control matured oocytes were subjected to 3% or 7% ethanol for 7 min. Oocytes from all groups were placed in fertilization medium (22 h) and culture medium (9 days). Ethanol at 0.05% during IVM did not induce oocyte PA, however, 3% and 7% ethanol were effective parthenogenetic inductors. Experiment 2: oocytes were cultured in maturation medium supplemented with 0, 50, 100 and 200 µM α-tocopherol, diluted in 0.05% ethanol. After in vitro fertilization and embryo culture, we assessed blastocyst apoptotic index and the transcription of a panel of genes. The results showed that supplementation with 100 µM α-tocopherol reduced apoptotic index and increased the expression of SOD2. In conclusion, 100 µM α-tocopherol, diluted in 0.05% ethanol, can be used during IVM to embryonic quality.


Assuntos
Suplementos Nutricionais , Etanol/farmacologia , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Partenogênese/efeitos dos fármacos , alfa-Tocoferol/farmacologia , Animais , Biomarcadores , Bovinos , Diferenciação Celular , Células Cultivadas , Fertilização in vitro , Regulação da Expressão Gênica no Desenvolvimento , Oócitos/citologia
10.
Antibiotics (Basel) ; 10(6)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34205962

RESUMO

Table grapes (Vitis vinifera) are affected by botrytis bunch rot and summer bunch rot, the latter a complex disease caused by Botrytis cinerea, Aspergillus spp., Penicillium expansum and Rhizopus stolonifer. To search for biocontrol alternatives, a new bioproduct composed of Gluconobacter cerinus and Hanseniaspora osmophila, a consortium called PUCV-VBL, was developed for the control of fungal rots in table grapes. Since this consortium presents new biocontrol species, the effect of their VOCs (volatile organic compounds) was evaluated under in vitro and in vivo conditions. The VOCs produced by the PUCV-VBL consortium showed the highest mycelial inhibition against Botrytis cinerea (86%). Furthermore, H. osmophila was able to inhibit sporulation of A. tubingensis and P. expansum. VOCs' effect in vivo was evaluated using berries from Red Globe, Thompson Seedless and Crimson Seedless grapes cultivars, demonstrating a mycelial inhibition by VOCs greater than 70% for all evaluated fungal species. The VOC identification of the PUCV-VBL consortium was analyzed by solid-phase microextraction coupled to gas chromatography-mass spectrometry (SPME-GCMS). A total 26 compounds were identified, including 1-butanol 3-methyl, propanoic acid ethyl ester, ethyl acetate, phenylethyl alcohol, isobutyl acetate and hexanoic acid ethyl ester. Our results show that VOCs are an important mode of action of the PUCV-VBL biological consortium.

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