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Ocorrência de hemoparasitas em cães: diagnóstico molecular e avaliação de coinfecções

2026-08-17T19:54:44Z

Título: Ocorrência de hemoparasitas em cães: diagnóstico molecular e avaliação de coinfecções Abstact: Tick-borne diseases in dogs represent a significant challenge for veterinary practice in urban areas of tropical regions. In São Luís, Maranhão, Brazil, the circulation of pathogens from the genera Ehrlichia, Anaplasma, Babesia, and Hepatozoon has been presumed based on previous serological studies, but remains poorly documented using molecular methods that allow sensitive detection, species-level identification, and assessment of coinfections. This study aimed to estimate the frequency of these agents and describe coinfection patterns in dogs treated at the Veterinary Hospital “Francisco Edilberto Uchoa Lopes” of the State University of Maranhão. A molecular survey was conducted using 200 whole blood samples collected between November 2024 and September 2025. DNA was extracted using a commercial kit, followed by screening with multiplex qPCR for Ehrlichia canis, Anaplasma platys, and Babesia spp., and nested PCR for Hepatozoon spp. Positive samples were confirmed by Sanger sequencing and BLASTn analysis. Overall, 39% (78/200) of samples were positive for at least one agent: 23% (46/200) for E. canis, 16.5% (33/200) for A. platys, 13% (26/200) for Babesia spp., and 3% (6/200) for Hepatozoon spp. Among positive samples, 32 presented coinfections. The most frequent association was A. platys + E. canis (10%; 20/200), followed by E. canis + Babesia spp. (4.5%; 9/200). Other combinations occurred at a frequency of 0.5% each (1/200): A. platys + Babesia spp., E. canis + Hepatozoon spp., and triple coinfection. Sequencing confirmed Babesia vogeli, A. platys, E. canis, and Hepatozoon canis (98.53–100% identity with national and international isolates). No significant differences were observed regarding sex or age group (p > 0.05), although a higher frequency trend was noted in dogs older than 5 years. These findings demonstrate the circulation of hemoparasites in dogs from São Luís, with predominance of E. canis and a notable occurrence of coinfections, contributing to the epidemiological understanding of these infections.

Diagnóstico do perfil tecnológico do abacaxi ‘Turiaçu’ e perspectivas da certificação territorial sob indicação geográfica

2026-08-11T17:55:08Z

Título: Diagnóstico do perfil tecnológico do abacaxi ‘Turiaçu’ e perspectivas da certificação territorial sob indicação geográfica Abstact: The ‘Turiaçu’ pineapple variety plays a prominent role in the Maranhão consumer market, occurs in the municipality of Turiaçu, and is recognized for its excellent physical-biometric and sensory quality. This quality results from the interaction between genetic factors, local soil and climate conditions and traditional cultural practices. This study aimed to evaluate and characterize the production process and technological profile of pineapple producers in the municipality, in addition to gathering information to support certification by Geographical Indication (GI) in the Denomination of Origin (DO) category, with an emphasis on the preparation of the technical specifications booklet. The municipality and producing communities were characterized, as well as a historical, cultural and socioeconomic survey of local pineapple production, the profile of producers and the technological level used in cultivation were characterized in a sample of 30% of producers, and the incidence of corky lesions on fruits in producing areas was assessed. Twenty-two rural communities were identified, totaling 231 producers active in the production of ‘Turiaçu’ pineapple. The communities of Serra dos Paz, Paxiba, Janaúba and Vila dos Castro concentrate the largest number of producers (55.0%). The profile of producers showed a predominance of family farmers, with low levels of education and an average age between 41 and 50 years. Most of the properties have less than 50 hectares, with pineapple crops in small areas. Production is mostly traditional, with little adoption of technologies and practices such as the slash-andburn system. The assessment of the incidence of cortical lesions revealed that 66.8% of the fruits presented cortical lesions, with an average of 3.8 lesions per fruit. Properties without technical assistance and rural extension (ATER) presented a higher incidence and severity of these lesions. Thus, the importance of technical assistance to improve fruit quality and reduce losses is highlighted. The Technical Specifications Notebook aims to guide producers on the parameters of production, harvesting, marketing, product representativeness and use of the brand. The GI certification by Denomination of Origin will add value to the ‘Turiaçu’ pineapple, strengthening its territorial identity and promoting the sustainable development of the region.

Vulnerabilidade à erosão na ilha do Maranhão: influência do clima e das mudanças de uso e cobertura do solo

2026-08-10T19:08:31Z

Título: Vulnerabilidade à erosão na ilha do Maranhão: influência do clima e das mudanças de uso e cobertura do solo Abstact: Coastal zones, such as São Luís Island, face challenges related to unplanned urbanization and erosive processes, exacerbated by forest degradation and changes in surface runoff. This study analyzed the relationship between anthropization and socio-environmental and climatic vulnerability in the region, investigating how changes in land use and vegetation intensify erosive processes and impact the local microclimate. The research considered variables such as soils, land use and cover, precipitation, geomorphology, and geology to identify areas susceptible to erosion. Two methodological approaches were adopted: first, maps were created through geoprocessing to delineate areas vulnerable to erosion, taking into account the characteristics of the meteorological stations of the Eastern Amazon; second, urban growth, loss of natural areas, and climatic variations over 30 years were analyzed. The results indicated a high vulnerability to erosion in São Luís Island, with significant impacts of land use on the microclimate, as evidenced by variations in precipitation and temperatures (maximum, minimum, and average). The study highlighted the need to strengthen territorial planning, particularly in the municipalities of Paço do Lumiar, Raposa, and São José de Ribamar, through instruments such as the Master Plan and the creation of conservation units. It is also essential to preserve protected areas threatened by deforestation and promote sustainable urbanization integrated with forest conservation. To improve environmental balance and quality of life, especially in communities dependent on agriculture and fishing, it is crucial to value the traditional knowledge of fishing communities. Future studies should focus on extreme climatic events to mitigate erosive impacts. The research reinforces the importance of integrated actions to address the environmental and socioeconomic challenges of São Luís Island.

Mediadores do acúmulo e da estabilidade do carbono orgânico do solo no trópico úmido

2026-08-10T19:04:16Z

Título: Mediadores do acúmulo e da estabilidade do carbono orgânico do solo no trópico úmido Abstact: Sustainable management and the assessment of soil health indicators in the humid tropics are urgent and necessary. Historically, this region has faced food insecurity, rural poverty, and degradation of natural resources. Simple fertilization is not sufficient to improve soil health due to rapid nutrient losses and accelerated organic matter decomposition, making integrated strategies necessary for more efficient agricultural systems. In this context, this research aims to (i) estimate the effect of polyvalent cations on the accumulation and stability of soil organic carbon in tropical regions; (ii) determine key indicators of soil health in the humid tropics; and (iii) understand the dynamics of Ca and Si on ecophysiological indices, stabilized soil organic carbon (SOC) fractions, and nitrogen use efficiency in soils of the Amazonian periphery. In Chapter 1, a meta-analysis was conducted based on 14 studies published between 2003 and 2023, using random-effects models to evaluate the influence of the polyvalent cations Al, Fe, Mg, and Ca on SOC concentration. The results revealed distinct effects among the cations (p < 0.001), with Al being the most strongly associated with increases in SOC, followed by Mg and Ca. In contrast, Fe showed the smallest effect. Heterogeneity among studies (I² = 77.01%) indicated that factors such as soil class, pH, texture, and land use significantly modulate cation effects. Soils with pH between 4 and 6 and clay contents above 600 g kg⁻¹ favored SOC concentrations > 30 g kg⁻¹, particularly in the presence of Ca contents exceeding 40,000 mg kg⁻¹. For the subsequent chapters, a field experiment was conducted in the municipality of São Luís, Maranhão, Brazil, from October 2021 to July 2024. A randomized complete block design (RCBD) was adopted with four replicates and eight treatments: (1) urea; (2) legume; (3) legume + urea; (4) calcium + legume; (5) silicon + legume; (6) calcium + legume + urea; (7) silicon + legume + urea; and (8) calcium + silicon + legume + urea, under maize cultivation. In Chapter 2, the contribution of 17 edaphic variables to SOC and maize productivity was investigated using multivariate analyses (PCA, RDA, decision trees, and regression). Chemical variables—especially MAOC, Si, and, to a lesser extent, Ca—exerted the greatest effects on SOC and productivity. MAOC was highly significant (p < 0.001) and showed a strong correlation (R² = 0.87) with total SOC, whereas physical and biological variables, such as macroporosity and microbial respiration, showed secondary influence. In the final chapter, the response of the ecophysiological indices qCO₂ and qMIC, as well as SOC fractions (POC and MAOC) and nitrogen, to the studied treatments was evaluated. The results demonstrated that Ca and Si contributed to increases in the stable carbon fraction (MAOC) (p < 0.05), with Si standing out by promoting MAOC contents 32% higher than Ca when combined with legumes. Nitrogen concentration in maize plants was 72% higher under Si + legume than under Ca + legume (p < 0.05). Silicon also showed greater efficiency in the use of biological nitrogen, in contrast to Ca, which depended on synthetic N to achieve a similar effect. Overall, the results of this research reinforce that sustainable management strategies prioritizing the addition of stabilizing cations and Si, the promotion of MAOC, and the use of biological N sources can improve soil health, increase agricultural productivity, and contribute to carbon storage and stability in soils. These strategies are fundamental to mitigating climate change impacts and ensuring the long-term resilience of tropical agroecosystems.