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1.
Int J Biometeorol ; 68(6): 1043-1060, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38453789

RESUMEN

In 2022, Mexico registered an increase in dengue cases compared to the previous year. On the other hand, the amount of precipitation reported annually was slightly less than the previous year. Similarly, the minimum-mean-maximum temperatures recorded annually were below the previous year. In the literature, it is possible to find studies focused on the spread of dengue only for some specific regions of Mexico. However, given the increase in the number of cases during 2022 in regions not considered by previously published works, this study covers cases reported in all states of the country. On the other hand, determining a relationship between the dynamics of dengue cases and climatic factors through a computational model can provide relevant information on the transmission of the virus. A multiple-learning computational approach was developed to simulate the number of the different risks of dengue cases according to the classification reported per epidemiological week by considering climatic factors in Mexico. For the development of the model, the data were obtained from the reports published in the Epidemiological Panorama of Dengue in Mexico and in the National Meteorological Service. The classification of non-severe dengue, dengue with warning signs, and severe dengue were modeled in parallel through an artificial neural network model. Five variables were considered to train the model: the monthly average of the minimum, mean, and maximum temperatures, the precipitation, and the number of the epidemiological week. The selection of variables in this work is focused on the spread of the different risks of dengue once the mosquito begins transmitting the virus. Therefore, temperature and precipitation were chosen as climatic factors due to the close relationship between the density of adult mosquitoes and the incidence of the disease. The Levenberg-Marquardt algorithm was applied to fit the coefficients during the learning process. In the results, the ANN model simulated the classification of the different risks of dengue with the following precisions (R2): 0.9684, 0.9721, and 0.8001 for non-severe dengue, with alarm signs and severe, respectively. Applying a correlation matrix and a sensitivity analysis of the ANN model coefficients, both the average minimum temperature and precipitation were relevant to predict the number of dengue cases. Finally, the information discovered in this work can support the decision-making of the Ministry of Health to avoid a syndemic between the increase in dengue cases and other seasonal diseases.


Asunto(s)
Dengue , Redes Neurales de la Computación , México/epidemiología , Dengue/epidemiología , Humanos , Tiempo (Meteorología) , Riesgo , Temperatura
2.
Plants (Basel) ; 13(4)2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38498543

RESUMEN

The citrus blackfly (CBF), Aleurocanthus woglumi Ashby, is an exotic pest native to Southeast Asia that has spread rapidly to the world's main centers of citrus production, having been recently introduced to Brazil. In this study, a maximum entropy niche model (MaxEnt) was used to predict the potential worldwide distribution of CBF under current and future climate change scenarios for 2030 and 2050. These future scenarios came from the Coupled Model Intercomparison Project Phase 6 (CMIP6), SSP1-2.6, and SSP5-8.5. The MaxEnt model predicted the potential distribution of CBF with area under receiver operator curve (AUC) values of 0.953 and 0.930 in the initial and final models, respectively. The average temperature of the coldest quarter months, precipitation of the rainiest month, isothermality, and precipitation of the driest month were the strongest predictors of CBF distribution, with contributions of 36.7%, 14.7%, 13.2%, and 10.2%, respectively. The model based on the current time conditions predicted that suitable areas for the potential occurrence of CBF, including countries such as Brazil, China, the European Union, the USA, Egypt, Turkey, and Morocco, are located in tropical and subtropical regions. Models from SSP1-2.6 (2030 and 2050) and SSP5-8.5 (2030) predicted that suitable habitats for CBF are increasing dramatically worldwide under future climate change scenarios, particularly in areas located in the southern US, southern Europe, North Africa, South China, and part of Australia. On the other hand, the SSP5-8.5 model of 2050 indicated a great retraction of the areas suitable for CBF located in the tropical region, with an emphasis on countries such as Brazil, Colombia, Venezuela, and India. In general, the CMIP6 models predicted greater risks of invasion and dissemination of CBF until 2030 and 2050 in the southern regions of the USA, European Union, and China, which are some of the world's largest orange producers. Knowledge of the current situation and future propagation paths of the pest serve as tools to improve the strategic government policies employed in CBF's regulation, commercialization, inspection, combat, and phytosanitary management.

3.
Bogotá; Instituto Nacional de Salud;Dirección de Vigilancia y Análisis del Riesgo en Salud Pública; 20240727. 1-38 p. TAB, graf, ilus.
No convencional en Español | COLNAL | ID: biblio-1566055

RESUMEN

Cuando se aborda el tema de la salud humana en relación con la meteorología y la climatología de un país, la atención de los investigadores suele centrarse en tres variables clave: temperatura, precipitación y humedad relativa. Estas variables son fundamentales para comprender las interacciones y su impacto en la salud ambiental, especialmente en las poblaciones más vulnerables. Se llevó a cabo una regresión geográficamente ponderada para el análisis de accidentes ofídicos, así como un modelo SARIMAX para evaluar la morbilidad relacionada con las consultas externas por infecciones respiratorias. El objetivo de este estudio es realizar un análisis exploratorio de las variables meteorológicas temperatura y precipitación con el fin de evaluar su influencia en el comportamiento endémico de enfermedades relevantes para la salud humana como lo son accidente ofídico y morbilidad por infección respiratoria aguda.


When addressing the topic of human health in relation to a country's meteorology and climatology, researchers' attention typically focuses on three key variables: temperature, precipitation, and relative humidity. These variables are essential to understand the interactions and their impact on environmental health, especially in the most vulnerable populations. A geographically weighted regression was carried out for the analysis of ophidic accidents, as well as a SARIMAX model to evaluate morbidity related to outpatient consultations for respiratory infections. He The objective of this study is to carry out an exploratory analysis of the variables meteorological temperature and precipitation in order to evaluate their influence on the endemic behavior of diseases relevant to human health such as ophidic accident and morbidity due to acute respiratory infection.


Asunto(s)
Cambio Climático
4.
Braz. j. biol ; 84: e259131, 2024. tab, graf, ilus
Artículo en Inglés | VETINDEX | ID: biblio-1384083

RESUMEN

Scolytinae species that, in high populations, can damage reducing wood production in forest crops. These beetles are monitored with traps baited with ethanol and increasing their efficiency can improve the integrated management of these insects. The objective was to evaluate the increase in the capture efficiency of Scolytinae with a semi-funnel trap model, in two experiments, one including wooden elements and other increasing the flight interception area and to correlate the numbers of these beetles collected with climatic factors. In the experiment 1, Eucalyptus urophylla S. T. Blake slats were directly attached to the collector flask and in another treatment, in addition to these slats, Cedrela sp. strips were inserted inside the bait holding hose. In the experiment 2, the insect interception area in the trap, originally 480 cm2, was expanded to 1,200 cm2 and compared with the model Pet-Santa Maria trap with an interception area of 550 cm2. Weekly collections were carried out between May 2018 and June 2019. The beetles collected were taken to the Wood Biodeterioration Laboratory of the Federal Rural University of Rio de Janeiro (UFRRJ) where they were sorted, identified at family level, counted and their number correlated with climatic factors. Statistical analyzes of the collected data were processed by the BioStat® 5.3 program. In the experiment 1 were collected 869 Scolytinae. The numbers of beetles collected per trap without modification, with E. urophylla slats and E. urophylla slats + Cedrela sp. strips were similar, 7.3 ± 3.8, 7.8 ± 6.2 and 7.7 ± 5.0 respectively. In the experiment 2 were collected 4,398 Scolytinae. Increasing the interception area of the beetles increased the efficiency of the semi-funnel trap, with 42.7 ± 20.5 Scolytinae collected compared to the original semi-funnel trap, 28.6 ± 12.6 and the Pet-Santa Maria, 20.4 ± 10.4, per trap. The number of Scolytinae did not correlate with climatic factors in the experiment 1 and it was correlated with temperature, relative humidity and wind speed, but not with precipitation, in the 2. The incorporation of E. urophylla slats or Cedrela sp. strips in the semi-funnel trap did not increase the number of beetles collected, but, the increase in the flight interception area and the temperature, relative humidity and wind speed were correlated with the number of beetles collected.


Espécies de besouros Scolytinae, em altas populações, podem danificar a madeira e reduzir a produtividade de cultivos florestais. Esses besouros são monitorados com armadilhas iscadas com etanol e o aumento da eficiência das mesmas pode melhorar o manejo integrado desses insetos. O objetivo foi avaliar o aumento da eficiência de captura de Scolytinae com armadilha modelo semifunil, em dois experimentos, um incluindo elementos de madeira e outro aumentando a área de interceptação de voo e correlacionar o número desses besouros coletados com fatores climáticos. No experimento 1, ripas de Eucalyptus urophylla S. T. Blake foram fixadas, diretamente, no frasco coletor e em outro tratamento, além dessas ripas, fitas de Cedrela sp. foram inseridas no interior da mangueira porta isca. No experimento 2, a área de interceptação de insetos na armadilha, originalmente, com 480 cm2, foi ampliada para 1200 cm2 e comparada com a armadilha modelo Pet-Santa Maria com área de interceptação de 550 cm2. Coletas semanais foram realizadas entre maio de 2018 a junho de 2019. Os insetos capturados foram levados ao Laboratório de Biodeterioração da Madeira da Universidade Federal Rural do Rio de Janeiro (UFRRJ) onde foram triados, identificados em nível de família, contados e a abundância correlacionada com fatores climáticos. As análises estatísticas dos dados coletados foram processadas pelo programa BioStat® 5.3. No experimento 1 foram coletados 869 Scolytinae. Os números de besouros coletados por armadilha sem modificação, com ripas de E. urophylla e com ripas de E. urophylla + fita de Cedrela sp. foram semelhantes, 7,3 ± 3,8; 7,8 ± 6,2 e 7,7 ± 5,0 respectivamente. No experimento 2 foram coletados 4398 Scolytinae. O aumento da área de interceptação dos besouros aumentou a eficiência da armadilha semifunil, com 42,7 ± 20,5 Scolytinae coletados por armadilha comparado a semifunil original, 28,6 ± 12,6 e a Pet-Santa Maria, 20,4 ± 10,4. O número de Scolytinae não se correlacionou com os fatores climáticos no experimento 1 e se correlacionou com a temperatura, umidade relativa e velocidade do vento, mas não com a precipitação, no 2. A incorporação de ripas de E. urophylla ou fitas de Cedrela sp. na armadilha semifunil não aumentou o número de besouros coletados, mas, o aumento da área de intercepção de voo e a temperatura, umidade relativa do ar e velocidade do vento se correlacionaram com o número de besouros coletados.


Asunto(s)
Animales , Escarabajos , Control de Plagas/instrumentación , Plagas Agrícolas , Etanol
5.
Braz. j. biol ; 83: e271354, 2023. tab, graf, ilus
Artículo en Inglés | VETINDEX | ID: biblio-1429995

RESUMEN

The fall armyworm [FAW; Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae)], is considered a serious invasive pest that poses a serious threat to world food security. It can completely devastate a whole country's cereal crops. Therefore, the present work is the 1st field trial in Egypt to elucidate some ecological aspects of S. frugiperda on maize plants (Single-Hybrid 168 Yellow Corn cultivar) at Esna district, Luxor Governorate, Egypt, throughout two sequential growing seasons of maize (2021-2022). Three insect parameters were used, i.e., egg masses, number of larvae, and percentage of damaged corn plants. Effects of certain climatic conditions and corn plant ages on S. frugiperda seasonal activity and damaged plants percentage were also estimated. S. frugiperda population initiated to attack maize plants from the 3rd week of June until the harvest in every season. S. frugiperda had two seasonal activity peaks in terms of egg masses numbers and three peaks regarding the larval population density/season. Its damage percentage increased with increasing plant age weekly. The mean of S. frugiperda egg masses were 2.83 ± 0.40 and 2.96 ± 0.45 mass /10 corn plants in 2021 and 2022, respectively. While, the overall mean larval populations were 13.41 ± 0.52 and 13.03 ± 0.46 larvae/10 plants, during the two growing seasons, respectively. Corn plant damage percentages reached 68.54 ± 2.71 and 60.42 ± 2.92% in 2021 and 2022, respectively. The combined effects of both the weather conditions and maize plant ages were highly significant on egg masses, larvae population density, and damage percentage, and varied from one season to another. The mean daily maximum temperature was the most effective variable on egg masses and the larval population. Maize plant age had a clear effect on the damage percentage caused by the larvae in the field during the two years of the study. The dramatic spread of FAW and the consequent damage (that appeared in different countries of America, Africa, and Asia) mean that different management approaches must be sought for the small and large-scale producers by using available technologies for smallholder farmers will eliminate pest damage without access to reach to an economic Injury level. This information may assist the decision maker when planning the S. frugiperda IPM program for maize plants and its surveillance.


A lagarta-do-cartucho [FAW; Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae)], é considerada uma séria praga invasora que representa uma séria ameaça à segurança alimentar mundial. Essa espécie pode devastar completamente as plantações de cereais de um país inteiro. Portanto, o presente trabalho é o primeiro ensaio de campo no Egito para elucidar alguns aspectos ecológicos de S. frugiperda em plantas de milho (Single-Hybrid 168 Yellow Corn cultivar) no distrito de Esna, Luxor Governorate, Egito, ao longo de duas estações de crescimento sequencial de milho (2021 a 2022). Três parâmetros de insetos foram utilizados, isto é, massas de ovos, número de larvas e porcentagem de plantas de milho danificadas. Também foram estimados os efeitos de certas condições climáticas e idades das plantas de milho na atividade sazonal de S. frugiperda e na porcentagem de plantas danificadas. A população de S. frugiperda começou a atacar as plantas de milho a partir da terceira semana de junho até a colheita em todas as estações. S. frugiperda apresentou dois picos sazonais de atividade como o número de massas de ovos e três picos em relação à densidade populacional larval/estação. Seu percentual de dano aumentou semanalmente a partir do aumento da idade da planta. A média das massas de ovos de S. frugiperda foi de 2,83 ± 0,40 e 2,96 ± 0,45 massa/10 plantas de milho em 2021 e 2022, respectivamente. Enquanto, as populações larvais médias gerais foram de 13,41 ± 0,52 e 13,03 ± 0,46 larvas/10 plantas, durante as duas estações de crescimento, respectivamente. As porcentagens de danos às plantas de milho atingiram 68,54 ± 2,71 e 60,42 ± 2,92% em 2021 e 2022, respectivamente. Os efeitos combinados das condições climáticas e da idade das plantas de milho foram altamente significativos nas massas de ovos, densidade populacional de larvas e porcentagem de danos, e variaram de uma estação para outra. A temperatura média diária máxima foi a variável mais efetiva sobre as massas de ovos e a população larval. A idade da planta de milho influenciou visivelmente o percentual de dano causado pelas larvas no campo durante os dois anos de estudo. A propagação dramática da LFM e os danos consequentes (que apareceram em diferentes países da América, África e Ásia) significam que devem ser utilizadas diferentes abordagens de gestão para os pequenos e grandes produtores, a partir de tecnologias disponíveis para os pequenos agricultores eliminarem os danos causados pelas pragas sem acesso para chegar a um nível de dano econômico. Essas informações podem auxiliar o tomador de decisão no planejamento do programa MIP de S. frugiperda para plantas de milho e o seu monitoramento.


Asunto(s)
Spodoptera , Plagas Agrícolas , Zea mays/parasitología
6.
Int J Trop Insect Sci ; 42(3): 2215-2220, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35136411

RESUMEN

Aedes aegypti is the main vector of dengue in the Americas and is also a transmitter of urban yellow fever arboviruses, Zika, and Chikungunya, all of which have substantial economic impacts on the affected countries. Through mathematical models, the influence of climatic factors on the oviposition of Ae. aegypti was determined. The data were collected in the city of Apucarana, Paraná State, using oviposition traps. Daily data were submitted to a negative binomial regression model (p < 0.05). The analyses were performed using the R statistical program to determine the climatic factors that most influenced oviposition. A Poisson regression showed that the variables temperature, atmospheric pressure, humidity, and precipitation significantly increased the number of eggs. However, using the semi-normal probability graph with a simulation envelope, it was determined that the Poisson regression model was not adequate to explain the relationships between the variables. Thus, a negative binomial regression model was used, which overcame the problem of overdispersion, and showed that only temperature affected the increase in the number of eggs, where an increase of 1 °C was expected to result in a 54.03% increase in the number of Ae. aegypti eggs.

7.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;55: e0072, 2022. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1406962

RESUMEN

ABSTRACT Background: The influence of climate on the epidemiology of dengue has scarcely been studied in Cartagena. Methods: The relationship between dengue cases and climatic and macroclimatic factors was explored using an ecological design and bivariate and time-series analyses during lag and non-lag months. Data from 2008-2017 was obtained from the national surveillance system and meteorological stations. Results: Cases correlated only with climatic variables during lag and non-lag months. Decreases in precipitation and humidity and increases in temperature were correlated with an increase in cases. Conclusions: Our findings provide useful information for establishing and strengthening dengue prevention and control strategies.

8.
Neotrop Entomol ; 50(1): 53-67, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33501635

RESUMEN

The first detection of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) in Brazil pointed to a gloomy future for South American agriculture in the 2012/2013 harvest, and insecticide sales increased exponentially during 2013 and 2014. However, after this outbreak, the population of this insect returned to manageable levels. This study documents data on H. armigera moth collection using light traps during the outbreak in two locations: (a) western region of the state of Bahia, including population levels of H. armigera and main noctuid pests during the big outbreak (February and March 2013); (b) Federal District, including monthly data for five growing seasons (July 2012-June 2017). During the outbreak, an average of 527.3 moths were collected per trap (cotton crop, March) in the western region of Bahia each night, while the maximum average in the Federal District was 75.4 moths (January). The number of moths decreased in the following growing seasons, and in October 2016, the maximum number was 2.8 moths per trap. Aspects related to the variations of H. armigera and Helicoverpa zea (Boddie) populations, including the study of phenology and relationship with climatic factors and Oceanic Niño Index, were analyzed and discussed. All aspects are approached to contribute to the management of lepidopteran pests, especially H. armigera, in the productive systems of the Brazilian Cerrado.


Asunto(s)
Agricultura , Mariposas Nocturnas , Animales , Brasil , Control de Plagas , Densidad de Población , Estaciones del Año
9.
Iheringia, Sér. zool ; 111: e2021001, 2021. tab, ilus, graf
Artículo en Inglés | VETINDEX | ID: biblio-1483406

RESUMEN

Agromyzidae (Insecta: Diptera) is a cosmopolitan family of acalyptrate flies, with almost 3,000 species worldwide distributed. Most species are leaf miners on a large number of plants. Among them, Liriomyza Mik, 1894 is a large genus of leaf-miner species that can cause significant damage to economically important crops and is considered agricultural pests, such as Liriomyza sativae Blanchard, 1938 and Liriomyza huidobrensis (Blanchard, 1926), which are herein investigated. The present study deals with the impact of climatic factors (temperature, humidity, and precipitation), seasonality, and parasitoid abundance on leaf-miner infestation during one year in five cultivated crops in Northeastern Brazil. Climatic factors for instance had different effects on L. sativae populations in melon and watermelon crops. Larval abundances were greater during the dry season for both species, L. sativae and L. huidobrensis, and abundance of adult parasitoids followed the increase of mining larvae.


Asunto(s)
Animales , Dípteros/crecimiento & desarrollo , Dípteros/parasitología , Efectos del Clima , Estaciones del Año
10.
Artículo en Inglés | LILACS-Express | VETINDEX | ID: biblio-1483438

RESUMEN

ABSTRACT Agromyzidae (Insecta: Diptera) is a cosmopolitan family of acalyptrate flies, with almost 3,000 species worldwide distributed. Most species are leaf miners on a large number of plants. Among them, Liriomyza Mik, 1894 is a large genus of leaf-miner species that can cause significant damage to economically important crops and is considered agricultural pests, such as Liriomyza sativae Blanchard, 1938 and Liriomyza huidobrensis (Blanchard, 1926), which are herein investigated. The present study deals with the impact of climatic factors (temperature, humidity, and precipitation), seasonality, and parasitoid abundance on leaf-miner infestation during one year in five cultivated crops in Northeastern Brazil. Climatic factors for instance had different effects on L. sativae populations in melon and watermelon crops. Larval abundances were greater during the dry season for both species, L. sativae and L. huidobrensis, and abundance of adult parasitoids followed the increase of mining larvae.

11.
Iheringia. Sér. Zool. ; 111: e2021001, 2021. tab, ilus, graf
Artículo en Inglés | VETINDEX | ID: vti-30407

RESUMEN

Agromyzidae (Insecta: Diptera) is a cosmopolitan family of acalyptrate flies, with almost 3,000 species worldwide distributed. Most species are leaf miners on a large number of plants. Among them, Liriomyza Mik, 1894 is a large genus of leaf-miner species that can cause significant damage to economically important crops and is considered agricultural pests, such as Liriomyza sativae Blanchard, 1938 and Liriomyza huidobrensis (Blanchard, 1926), which are herein investigated. The present study deals with the impact of climatic factors (temperature, humidity, and precipitation), seasonality, and parasitoid abundance on leaf-miner infestation during one year in five cultivated crops in Northeastern Brazil. Climatic factors for instance had different effects on L. sativae populations in melon and watermelon crops. Larval abundances were greater during the dry season for both species, L. sativae and L. huidobrensis, and abundance of adult parasitoids followed the increase of mining larvae.(AU)


Asunto(s)
Animales , Dípteros/crecimiento & desarrollo , Dípteros/parasitología , Efectos del Clima , Estaciones del Año
12.
Rev. bras. parasitol. vet ; 30(2): e025620, 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1251370

RESUMEN

Abstract Fascioliasis is a freshwater snail-borne zoonotic disease. The Northern Bolivian Altiplano is a very high altitude endemic area where the highest human prevalences and intensities have been reported. Preventive chemotherapy by treatment campaigns is yearly applied. However, liver fluke infection of cattle, sheep, pigs and donkeys assures endemicity and consequent human infection and re-infection risks. A One Health action has therefore been implemented. Activity concerns lymnaeid vectors and environment diversity. Studies included growth, egg-laying and life span in laboratory-reared lymnaeids. Different habitat types and influencing factors were assessed. All populations proved to belong to Galba truncatula by rDNA sequencing. Analyses comprised physico-chemical characteristics and monthly follow-up of water temperature, pH and quantity, and lymnaeid abundance and density. Population dynamics in the transmission foci differed. Mean environmental temperature was lower than fluke development minimum temperature threshold, but water temperature was higher, except during winter. A two generations/year pattern appeared in permanent water habitats, and one generation/year pattern in habitats drying out for months. The multidisciplinary control measures can be extended from one part of the endemic area to another. These studies, made for the first time at very high altitude, constitute a baseline useful for fascioliasis control in other countries.


Resumo A fasciolíase é uma doença zoonótica transmitida para os humanos por formas evolucionárias de Fasciola hepatica oriundas de limneídeos infectados. O Altiplano Boliviano Norte é uma área endêmica de altitude muito alta, onde foram relatadas as maiores prevalências e intensidades em infecções humanas. A quimioterapia preventiva por campanhas de tratamento é aplicada anualmente. No entanto, infecção por Fasciola hepatica em bovinos, ovelhas, suínos e asininos garante endemicidade e consequentes riscos de infecção e reinfecção humana. Portanto, ações norteadas no conceito "One Health" foram implementadas. As atividades envolveram os limneídeos e a avaliação da diversidade de ambientes. Os estudos incluíram o crescimento, postura de ovos e expectativa de vida de limneídeos criados em laboratório, bem como a avaliação da influência dos diferentes hábitats. Todas as populações foram identificadas como Galba truncatula por meio do sequenciamento de rDNA. As análises incluíram características físico-químicas e acompanhamento mensal da temperatura, pH, quantidade da água, abundância e densidade de limneídeos. A dinâmica populacional nos focos de transmissão diferiu. A temperatura ambiente média foi mais baixa do que o limite mínimo de temperatura do desenvolvimento do helminto, mas a temperatura da água foi mais alta, exceto durante o inverno. Um padrão de duas gerações/ano apareceu em hábitats com água permanente, enquanto um padrão de uma geração/ano foi observado em habitats que ficam secos durante meses. Os resultados permitem concluir que as medidas multidisciplinares de controle podem ser estendidas de uma parte da área endêmica para outra. Esses estudos, realizados pela primeira vez em altitudes muito elevadas, constituem uma base útil e extrapolável para o controle da fasciolíase.


Asunto(s)
Animales , Enfermedades de las Ovejas , Enfermedades de los Bovinos/epidemiología , Fasciola hepatica , Fascioliasis/veterinaria , Fascioliasis/epidemiología , Salud Única , Porcinos , Enfermedades de los Porcinos , Biología , Bolivia , Bovinos , Ovinos , Dinámica Poblacional
13.
Sci. agric ; 76(5): 376-388, Sept.-Oct. 2019. tab, ilus, graf
Artículo en Inglés | VETINDEX | ID: biblio-1497806

RESUMEN

Details on growth and yield for cassava planted on different dates are useful for determining suitable genotypes for particular growing seasons. Our aim was to study growth and yield of cassava planted on different dates. Four cassava genotypes (Kasetsart 50, Rayong 9, Rayong 11 and CMR38-125-77) were evaluated using a randomized complete block design (RCBD) with four replications in six growing periods (20 Apr, 25 May, 30 June, 5 Oct, 10 Nov and 15 Dec 2015-2016) at Khon Kaen, Thailand. Soil properties were determined prior to planting, and crop traits and weather data were recorded. The six planting dates had a statistically significant effect on all crop traits. Low temperatures and solar radiation related to low biomass accumulation rates and short periods of linear phases for total crop and storage root dry weights with the 30 June planting date. CMR38-125-77 is likely to be a good genotype with respect to total crop and storage root dry weights at final harvest for almost all growing dates, except for the 20 Apr. Leaf area index (LAI) at 120, 240 and 300 days after planting (DAP), specific leaf area (SLA) at 120 DAP, storage root growth rate (SRGR) during 300-360 DAP and leaf growth rate (LGR) during 60-120 and 300-360 DAP were the components for the physiological determinants of total crop and storage root dry weight. The relationship between these physiological traits and storage root could be useful for cassava breeding.


Asunto(s)
Efectos del Clima , Manihot/crecimiento & desarrollo , 24444 , Tailandia
14.
Sci. agric. ; 76(5): 376-388, Sept.-Oct. 2019. tab, ilus, graf
Artículo en Inglés | VETINDEX | ID: vti-24487

RESUMEN

Details on growth and yield for cassava planted on different dates are useful for determining suitable genotypes for particular growing seasons. Our aim was to study growth and yield of cassava planted on different dates. Four cassava genotypes (Kasetsart 50, Rayong 9, Rayong 11 and CMR38-125-77) were evaluated using a randomized complete block design (RCBD) with four replications in six growing periods (20 Apr, 25 May, 30 June, 5 Oct, 10 Nov and 15 Dec 2015-2016) at Khon Kaen, Thailand. Soil properties were determined prior to planting, and crop traits and weather data were recorded. The six planting dates had a statistically significant effect on all crop traits. Low temperatures and solar radiation related to low biomass accumulation rates and short periods of linear phases for total crop and storage root dry weights with the 30 June planting date. CMR38-125-77 is likely to be a good genotype with respect to total crop and storage root dry weights at final harvest for almost all growing dates, except for the 20 Apr. Leaf area index (LAI) at 120, 240 and 300 days after planting (DAP), specific leaf area (SLA) at 120 DAP, storage root growth rate (SRGR) during 300-360 DAP and leaf growth rate (LGR) during 60-120 and 300-360 DAP were the components for the physiological determinants of total crop and storage root dry weight. The relationship between these physiological traits and storage root could be useful for cassava breeding.(AU)


Asunto(s)
Manihot/crecimiento & desarrollo , Efectos del Clima , 24444 , Tailandia
15.
Pesqui. vet. bras ; 39(6): 429-433, jun. 2019. tab, graf
Artículo en Inglés | VETINDEX | ID: vti-23794

RESUMEN

Bats belong to the order Chiroptera, family Phyllostomidae, and present a wide diversity of reproductive strategies. However, information on the reproductive biology of male bats is scarce, mainly in the Northeast Region of Brazil. Thus, this study evaluated the seasonal testicular histomorphometry of the bat Carollia perspicillata in fragments of the Atlantic Forest in Pernambuco state. To this end, adult males were collected, euthanized for removal of the testicles, and later submitted to a routine histological technique. Histomorphometric analysis included assessment of the areas of tubular and intertubular compartment occupation, as well as quantification of spermatocytes, rounded spermatids, elongated spermatids, and Sertoli and Leydig cells. Results indicated that this bat species presents reproductive seasonality, because significantly higher averages of the testicular parameters were observed in the rainy season, which is a period of greater availability of food resources. Such inferences indicate that there is a synchrony between peak spermatogenesis and hormonal inversion in the months of high precipitation; furthermore, a higher carrying capacity of the Sertoli cells is noted. C. perspicillata males possibly present greater sperm and androgenic activity in the rainy season, associated with increased tubular area and number of spermatogenic cells, as well as with the intertubular area and number of Leydig cells, respectively.(AU)


Os morcegos pertencem a ordem Chiroptera, família Phyllostomidae, e apresentam ampla diversidade de estratégias reprodutivas. Entretanto, as informações relacionadas à biologia reprodutiva dos machos são escassas, principalmente no Nordeste do Brasil. Dessa forma, o trabalho avaliou a histomorfometria sazonal testicular de Carollia perspicillata em fragmentos de Mata Atlântica de Pernambuco. Para tanto, os machos adultos foram coletados, eutanasiados para a remoção dos testículos, e posteriormente submetidos à técnica histológica de rotina. As análises histomorfométricas avaliaram as áreas de ocupação do compartimento tubular e intertubular, assim como a quantificação dos espermatócitos, espermátides arredondadas, espermátides alongadas, células de Sertoli e de Leydig. Os resultados indicaram que a espécie apresenta sazonalidade reprodutiva, visto que maiores médias significativas dos parâmetros testiculares foram encontradas na estação chuvosa, que é um período de maior disponibilidade de recursos alimentares. Tais inferências indicam que existe uma sincronia entre o pico de espermatogênese e investimento hormonal nos meses de alta precipitação, atrelado a isso, nota-se ainda, uma maior capacidade de suporte das células de Sertoli. Os machos de C. perspicillata possivelmente apresentam uma maior atividade espermática e androgênica na estação chuvosa, associadas ao aumento da área tubular e do número de células espermatogênicas, assim como da área intertubular e do número das células de Leydig, respectivamente.(AU)


Asunto(s)
Animales , Estaciones del Año , Quirópteros/anatomía & histología , Quirópteros/fisiología
16.
Pesqui. vet. bras ; Pesqui. vet. bras;39(6): 429-433, June 2019. tab, graf
Artículo en Inglés | VETINDEX, LILACS | ID: biblio-1012762

RESUMEN

Bats belong to the order Chiroptera, family Phyllostomidae, and present a wide diversity of reproductive strategies. However, information on the reproductive biology of male bats is scarce, mainly in the Northeast Region of Brazil. Thus, this study evaluated the seasonal testicular histomorphometry of the bat Carollia perspicillata in fragments of the Atlantic Forest in Pernambuco state. To this end, adult males were collected, euthanized for removal of the testicles, and later submitted to a routine histological technique. Histomorphometric analysis included assessment of the areas of tubular and intertubular compartment occupation, as well as quantification of spermatocytes, rounded spermatids, elongated spermatids, and Sertoli and Leydig cells. Results indicated that this bat species presents reproductive seasonality, because significantly higher averages of the testicular parameters were observed in the rainy season, which is a period of greater availability of food resources. Such inferences indicate that there is a synchrony between peak spermatogenesis and hormonal inversion in the months of high precipitation; furthermore, a higher carrying capacity of the Sertoli cells is noted. C. perspicillata males possibly present greater sperm and androgenic activity in the rainy season, associated with increased tubular area and number of spermatogenic cells, as well as with the intertubular area and number of Leydig cells, respectively.(AU)


Os morcegos pertencem a ordem Chiroptera, família Phyllostomidae, e apresentam ampla diversidade de estratégias reprodutivas. Entretanto, as informações relacionadas à biologia reprodutiva dos machos são escassas, principalmente no Nordeste do Brasil. Dessa forma, o trabalho avaliou a histomorfometria sazonal testicular de Carollia perspicillata em fragmentos de Mata Atlântica de Pernambuco. Para tanto, os machos adultos foram coletados, eutanasiados para a remoção dos testículos, e posteriormente submetidos à técnica histológica de rotina. As análises histomorfométricas avaliaram as áreas de ocupação do compartimento tubular e intertubular, assim como a quantificação dos espermatócitos, espermátides arredondadas, espermátides alongadas, células de Sertoli e de Leydig. Os resultados indicaram que a espécie apresenta sazonalidade reprodutiva, visto que maiores médias significativas dos parâmetros testiculares foram encontradas na estação chuvosa, que é um período de maior disponibilidade de recursos alimentares. Tais inferências indicam que existe uma sincronia entre o pico de espermatogênese e investimento hormonal nos meses de alta precipitação, atrelado a isso, nota-se ainda, uma maior capacidade de suporte das células de Sertoli. Os machos de C. perspicillata possivelmente apresentam uma maior atividade espermática e androgênica na estação chuvosa, associadas ao aumento da área tubular e do número de células espermatogênicas, assim como da área intertubular e do número das células de Leydig, respectivamente.(AU)


Asunto(s)
Animales , Estaciones del Año , Quirópteros/anatomía & histología , Quirópteros/fisiología
17.
Animal ; 13(1): 221-230, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29785891

RESUMEN

Climate change is producing an increase on extreme weather events around the world such as flooding, drought and extreme ambient temperatures impacting animal production and animal welfare. At present, there is a lack of studies addressing the effects of climatic conditions associated with energy intake in finishing cattle in South American feed yards. Therefore, two experiments were conducted to assess the effects of environmental variables and level of metabolizable energy intake above maintenance requirements (MEI) on performance and carcass quality of steers. In each experiment (winter and summer), steers were fed with 1.85 or 2.72 times of their requirements of metabolizable energy of maintenance. A total of 24 crossbred steers per experiment were used and located in four pens (26.25 m2/head) equipped with a Calan Broadbent Feeding System. Animals were fed with the same diet within each season, varying the amount offered to adjust the MEI treatments. Mud depth, mud scores, tympanic temperature (TT), environmental variables, average daily gain, respiration rates and carcass characteristics plus three thermal comfort indices were collected. Data analysis considered a factorial arrangement (Season and MEI). In addition, a repeated measures analysis was performed for TT and respiration rate. Mean values of ambient temperature, solar radiation and comfort thermal indices were greater in the summer experiment as expected (P<0.005). The mean values of TT were higher in steers fed with higher MEI and also in the summer season. The average daily gain was greater during summer v. winter (1.10±0.11 v. 0.36±0.06) kg/day, also when steers were fed 2.72 v. 1.85 MEI level (0.89±0.12 v. 0.57±0.10) kg/day. In summer, respiration rate increased in 41.2% in the afternoon. In winter, muddy conditions increased with time of feeding, whereas wind speed and rainfall had significant effects on TT and average daily gain. We conclude that MEI and environmental variables have direct effects on the physiology and performance of steers, including TT and average daily gain, particularly during the winter. In addition, carcass characteristics were affected by season but not by the level of MEI. Finally, due to the high variability of data as well as the small number of animals assessed in these experiments, more studies on carcass characteristics under similar conditions are required.


Asunto(s)
Alimentación Animal/análisis , Bovinos/fisiología , Ingestión de Energía/fisiología , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Bovinos/crecimiento & desarrollo , Chile , Cambio Climático , Dieta/veterinaria , Masculino , Estaciones del Año
18.
Rev. bras. ciênc. avic ; 20(4): 731-736, Oct.-Dec. 2018. tab
Artículo en Inglés | VETINDEX | ID: biblio-1490564

RESUMEN

Hilly chickens were characterized from January 2015 to September 2016 considering climate factors (light and heat). The experimental birds were divided into three groups (heat stress; light and control). The heat was generated in the chickens shelter by a black shaded light (Lantern) for two to three hours more after sunset. A lighting device (Lantern) was kept in the chickens shelter for the same period for increasing daylight duration. The individual chickens egg production, egg weight and mature live weight were studied from onset of egg production. It was observed that reddish brown hilly type chicken produced more (100.80 no/year/chicken) and larger sized (43.21g) eggs than spotted chicken (83.4 no/year/chicken and 40.46g). Among the three treatments, the lighting group produced 7.71 and 5.60 more eggs than the control and heat stress group, and one hour lighting lengths increased egg production 4 to 5.8%. Fifty-five blood samples were collected, and DNA was isolated from whole blood. For genetic characterization, 10 microsatellites markers from FAO recommendation list were used in this study. PCR amplification was performed in an MJ PTC-200 Peltier Thermal Cycler. The gene flow among breeds and genetic differentiation was assessed by computing between-breed genetic parameters: molecular co-ancestry (fij). It was found that genetic diversity of these two types of chickens was moderate. Results indicated that they were originated from the same ancestor. Therefore, priority should be given for implementation of appropriate breeding programme and strategies are necessary to avoid loss of genetic diversity.


Asunto(s)
Animales , Pollos/fisiología , Pollos/genética , Luz/efectos adversos , Repeticiones de Microsatélite , Calor/efectos adversos , Variación Genética , Huevos , Reacción en Cadena de la Polimerasa/veterinaria
19.
R. bras. Ci. avíc. ; 20(4): 731-736, Oct.-Dec. 2018. tab
Artículo en Inglés | VETINDEX | ID: vti-19845

RESUMEN

Hilly chickens were characterized from January 2015 to September 2016 considering climate factors (light and heat). The experimental birds were divided into three groups (heat stress; light and control). The heat was generated in the chickens shelter by a black shaded light (Lantern) for two to three hours more after sunset. A lighting device (Lantern) was kept in the chickens shelter for the same period for increasing daylight duration. The individual chickens egg production, egg weight and mature live weight were studied from onset of egg production. It was observed that reddish brown hilly type chicken produced more (100.80 no/year/chicken) and larger sized (43.21g) eggs than spotted chicken (83.4 no/year/chicken and 40.46g). Among the three treatments, the lighting group produced 7.71 and 5.60 more eggs than the control and heat stress group, and one hour lighting lengths increased egg production 4 to 5.8%. Fifty-five blood samples were collected, and DNA was isolated from whole blood. For genetic characterization, 10 microsatellites markers from FAO recommendation list were used in this study. PCR amplification was performed in an MJ PTC-200 Peltier Thermal Cycler. The gene flow among breeds and genetic differentiation was assessed by computing between-breed genetic parameters: molecular co-ancestry (fij). It was found that genetic diversity of these two types of chickens was moderate. Results indicated that they were originated from the same ancestor. Therefore, priority should be given for implementation of appropriate breeding programme and strategies are necessary to avoid loss of genetic diversity.(AU)


Asunto(s)
Animales , Calor/efectos adversos , Luz/efectos adversos , Pollos/genética , Pollos/fisiología , Repeticiones de Microsatélite , Variación Genética , Huevos , Reacción en Cadena de la Polimerasa/veterinaria
20.
Cad. saúde colet., (Rio J.) ; 26(4): 446-452, out.-dez. 2018. tab, graf
Artículo en Portugués | LILACS | ID: biblio-984148

RESUMEN

Resumo Introdução A dengue é considerada um problema de saúde pública. O município de Ribeirão Preto possui condições climáticas e geográficas favoráveis à proliferação do Aedes aegypti , sendo reportadas altas taxas de incidência de dengue. Objetivo Avaliar a relação entre a precipitação pluviométrica e a incidência de casos confirmados de dengue. Método Foi utilizado o coeficiente de correlação de Spearman para a análise da relação entre a pluviosidade e a incidência de dengue. Resultados Encontrou-se associação entre a precipitação e os casos de dengue, com p < 0,01, considerando um intervalo de defasagem (time lag ) que ocorre a partir do primeiro mês e se estende até o quinto mês. Conclusão Estudos como este contribuem para o conhecimento sobre a influência de fatores climáticos na incidência e na dinâmica de transmissão da dengue, sendo essenciais para auxiliar os gestores na tomada de decisão para a prevenção e o controle da doença.


Abstract Background Dengue is considered a public health problem. The municipality of Ribeirão Preto has climatic and geographical conditions conducive to the proliferation of Aedes aegypti and high rates of dengue incidence are reported. Objective To evaluate the relationship between rainfall and the incidence of confirmed cases of dengue. Method The Spearman Correlation Coefficient was used to analyze the relationship between rainfall and the dengue incidence. Results An association between precipitation and dengue cases was found, with p < 0.01, considering a time lag, which occurs from the first month until the fifth month. Conclusion Studies such as this contribute to the knowledge about the influence of climatic factors on the incidence and transmission dynamics of dengue fever, being essential to guide managers in decision making for disease prevention and control.

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