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Detecção de parasitas do gênero Trypanosoma em pequenos ruminantes no norte maranhense, Brasil

2025-06-09T00:00:00Z

Título: Detecção de parasitas do gênero Trypanosoma em pequenos ruminantes no norte maranhense, Brasil Abstact: Animal trypanosomiasis represents a significant sanitary and economic challenge for tropical livestock production, causing severe anemia and systemic inflammation in ruminants. In Brazil, Trypanosoma vivax is the most clinically relevant species in goats and sheep, associated with high morbidity, mortality, and production losses, though infections may also occur asymptomatically. While T. evansi and T. theileri can infect small ruminants, their pathogenicity in these hosts is considered low. In Maranhão state, the complete absence of studies on trypanosomiasis in small ruminants represents a critical epidemiological gap, leaving herds vulnerable to undiagnosed outbreaks. This study aimed to detect Trypanosoma spp. in small ruminants across Maranhão using direct and indirect diagnostic methods. Blood samples were collected from 84 goats and 210 sheep across 14 farms in São Bento, Pinheiro, and Itapecuru-Mirim municipalities during both dry and rainy seasons. A structured questionnaire documented risk factors, and individual animal records included demographic and health data. Diagnostic approaches included direct microscopy of blood smears, indirect ELISA for anti-T. vivax antibodies, species-specific PCR targeting T. vivax, T. evansi, and T. theileri genomic fragments, sequencing and phylogenetic analysis of PCR-positive samples (BLAST against GenBank), and statistical analysis using Chi-square and Fisher's exact tests for risk factors. No trypanosomes were detected by microscopy. Seroprevalence reached 14.28% (42/294), with 30 (10.20%) goats and 12 (4.08%) sheep testing positive. Two samples (0.68%) were PCR-positive for T. vivax, showing 100% identity with Brazilian isolates from buffaloes, cattle, small ruminants, and donkeys in GenBank. Phylogenetic analysis confirmed homology with these T. vivax strains. All samples tested negative for T. evansi and T. theileri. Significant risk factors (p<0.05) included host species (higher in goats), recent animal acquisitions, veterinary care availability, farm infrastructure quality, and housing type. This study provides the first molecular evidence of T. vivax infection in Maranhão's small ruminants, highlighting the need for control measures. The findings expand understanding of animal trypanosomiasis in Brazil and underscore the vulnerability of small ruminant production systems to this neglected disease.

Ensino médico veterinário: percepção sobre o ensino de diagnóstico por imagem entre discentes e egressos de São Luís do Maranhão

2024-08-30T00:00:00Z

Título: Ensino médico veterinário: percepção sobre o ensino de diagnóstico por imagem entre discentes e egressos de São Luís do Maranhão Abstact: Veterinary medical education takes place in colleges, university centers and universities, in Brazil the mandatory registration of this diploma came in 1940, since then courses have been emerging, taking shape from the needs of the regions of implementation and thus many changes occur throughout the history of each veterinary medicine course. In Maranhão, changes occur in relation to the general workload, mandatory, elective, common and professional subjects, but they always occur with the intention of complying with the National Curricular Guidelines. After decades of its creation, the veterinary medicine course at the state university of Maranhão underwent an update of the course's pedagogical project, in 1995 the subjects of Methods and Techniques to Support Diagnosis I and II were created, with I being for the teaching clinical pathology and II for teaching imaging techniques that would assist the veterinarian's clinical routine, respectively with 90 and 60 hours, techniques to support diagnosis II became image diagnosis with 60 hours which remains with this load hourly to the present day after four updates to the course's pedagogical project, but with considerable changes in the wording of the syllabus and the direction of basic and complementary references. The effects of this form of teaching are observed in the questionnaires answered by students and graduates of the Veterinary Medicine course at the State University of Maranhão

Caracterização clínica, histológica e molecular da gengivite estomatite crônica felina

2023-01-01T00:00:00Z

Título: Caracterização clínica, histológica e molecular da gengivite estomatite crônica felina Abstact: Feline chronic gingivostomatitis (FCGS) is a severe inflammatory disease characterized by diffuse or focal ulcerative and/or proliferative lesions affecting the alveolar, lingual, and buccal mucosae. Its etiology is considered multifactorial, involving infectious, immunological, and environmental factors. Definitive diagnosis requires detailed anamnesis, thorough clinical examination, and complementary tests. The present study aimed to characterize oral lesions in 30 cats affected by FCGS through clinical, histological, and molecular analyses. Clinically, the disease was more frequent in young adult animals, accounting for 70%, and less common in geriatric individuals (10%). Among the clinical signs, halitosis was observed in all cases, while ptyalism, oral discomfort, and hyporexia occurred in 63.3% of the animals. Oral examination revealed ulcerative and proliferative lesions in all cats, affecting the pharynx, glossopalatine arch, gingival, alveolar, and buccal mucosae, often extending to the lateral base of the tongue. These lesions exhibited intense reddish coloration, friable consistency, and bleeding upon manipulation. Additionally, 100% , of the animals presented lesions compatible with tooth resorption. Histopathological analysis revealed inflammatory infiltrates predominantly composed of plasma cells and lymphocytes, epithelial hyperplasia, ulcerations, necrosis, and reparative areas characterized by granulation tissue and fibrosis. Diagnostic tests for FeLV and Leishmania spp. were negative in all animals, while three tested positive for FIV. The findings confirm the chronic nature of FCGS and demonstrate that, although it may be associated with immunosuppression, the disease does not rely exclusively on this condition for its manifestation.

Revisão sistemática e meta-análise da prevalência de Leishmania spp. em vetores da leishmaniose tegumentar americana no Brasil e mapeamento de áreas prioritárias para sua vigilância na região Nordeste do país

2026-01-29T00:00:00Z

Título: Revisão sistemática e meta-análise da prevalência de Leishmania spp. em vetores da leishmaniose tegumentar americana no Brasil e mapeamento de áreas prioritárias para sua vigilância na região Nordeste do país Abstact: American cutaneous leishmaniasis (ACL) is a neglected disease whose transmission involves complex interactions among different protozoan species of the genus Leishmania, sand fly vectors, and vertebrate hosts in diverse ecological settings. This dissertation is organized into an introductory chapter of general considerations, followed by two chapters written in the format of scientific articles, which investigate the ecology and epidemiology of ACL. The second chapter presents a systematic review and meta-analysis focusing on natural Leishmania spp. infection prevalence and blood meal sources of vectors in Brazil. Data from 71 studies were synthesized, revealing a pooled prevalence of 2.17% (n=52,315 specimens). The vectors of greatest epidemiological importance were Nyssomyia whitmani (3.54%) and N. umbratilis (1.71%), with the latter standing out as the main vector of L. (V.) guyanensis in the Amazon. N. whitmani demonstrated trophic and parasitic plasticity, with infection by different Leishmania species and an infection rate for L. (V.) braziliensis of 1.03%. Blood meal analysis revealed a high frequency of detection for animal groups commonly found in peridomestic settings, such as birds (35.75%) and humans (21.35%), suggesting vector interaction with anthropized environments. The third chapter focused on mapping ATL risk in Northeast Brazil (2013-2024), integrating ecological niche modeling, spatial autocorrelation analysis, and space-time scanning. The vector suitability model (AUC = 0.86 ± 0.02) identified precipitation of the coldest quarter as the main environmental determinant, with high suitability in eastern Maranhão, northern Piauí, and the Atlantic Forest coastal strip. Disease incidence showed strong positive spatial autocorrelation [Moran's (I) coefficient = 0.55; p < 0.05], forming High-High clusters concentrated in the states of Maranhão (58.1% of municipalities), Bahia (36.5%), and Ceará (13.5%). Space-time scanning detected 18 recent (2021-2024) high-risk clusters, with notable clusters in the states of Bahia [Relative Risk (RR) = 29.7] and Ceará (RR = 70.6). Bivariate LISA analysis demonstrated that high-incidence clusters spatially overlap areas of high forest cover (I = 0.32) and extreme social vulnerability, especially lack of urban infrastructure (I = 0.13) and low human capital (I = 0.09), with high concentration in Maranhão. The confluence of high vector suitability and high incidence identified priority municipalities for surveillance in Maranhão (40.4%) and Bahia (35.8%). In summary, these findings confirm that ACL transmission is driven by a combination of specific vector species with ecological plasticity and distinct epidemiological profiles, and spatially defined hotspots where environmental suitability converges with critical socioeconomic vulnerability. The identification of N. whitmani and N. umbratilis as key vectors, along with the precise mapping of priority areas in Maranhão, Bahia, and Ceará, provides support for the implementation of integrated surveillance and control strategies, focused on the municipalities and epidemiological scenarios with the highest identified risk.