Abstract Organic fertilization can significantly increase productivity in crop-livestock integration systems, by improving soil quality. To investigate this, the study evaluated the effects of organic sources on Urochloa hybrid 'BRS Ipyporã' grown after soybeans in an air-conditioned greenhouse. Using a randomized block design, 10 treatments were established in a factorial scheme (2x5). The first factor consisted of two types of soil, with and without a history of application of swine manure, incorporated into five types of substrates: mineral fertilizer, Uberlândia compost, Rio Verde compost, poultry litter, and swine manure, with five replications. While soybean plants exhibited no treatment effects on plant height, leaf number, photosynthetic rate, transpiration rate, stomatal conductance, ratio between internal and external CO2 concentrations, instantaneous water use efficiency, intrinsic water use efficiency, chlorophyll a and chlorophyll b, those grown in manure-historied soils treated with Rio Verde compost produced higher dry mass of leaves, stems, and total biomass. Conversely, forage plants thrived in soils without a history of manure application, demonstrating greater stem, root, and total dry mass. Soils with a history of swine manure application exhibited higher concentrations of phosphorus, copper, and zinc. Additionally, the enzymes arylsulfatase, β-glucosidase, and acid phosphatase concentrations in the soil were significantly enhanced by the continuous application of swine manure over time.

Resumo A adubação orgânica pode aumentar significativamente a produtividade das culturas em sistemas de integração lavoura-pecuária, pela melhoria da qualidade do solo. Para investigar isso, foram avaliados neste trabalho os efeitos de fontes orgânicas no cultivo do híbrido Urochloa 'BRS Ipyporã' cultivada após a soja em casa-de-vegetação climatizada. O ensaio foi delineado em blocos casualizados e dez tratamentos foram arranjados em esquema fatorial (2x5). O primeiro fator foi composto por dois tipos de solo, com e sem histórico de aplicação de dejetos suínos, incorporados em cinco tipos de substratos: adubo mineral, composto de Uberlândia, composto de Rio Verde, cama de frango e dejeto de suínos, com cinco repetições. Embora as plantas de soja não tenham apresentado efeitos de tratamento na altura da planta, número de folhas, taxa fotossintética, taxa de transpiração, condutância estomática, razão entre concentrações internas e externas de CO2, eficiência instantânea do uso da água, eficiência intrínseca do uso da água, clorofila a e clorofila b, aquelas cultivadas em solos com histórico de esterco tratados com composto Rio Verde produziram maior massa seca de folhas, caules e biomassa total. Por outro lado, as plantas forrageiras produziram maior massa seca de caule, raiz e total em solos sem histórico de aplicação de esterco. Solos com histórico de aplicação de dejetos suínos apresentaram maiores concentrações de fósforo, cobre e zinco. Além disso, as concentrações das enzimas arilsulfatase, β-glicosidase e fosfatase ácida no solo foram significativamente aumentadas pela aplicação contínua de dejetos suínos ao longo do tempo.

Abstract To assess the effect of cleaning protocols on dentin contaminated with blood in reparative endodontic materials, bovine root samples were divided: no contamination (N); contamination (P); contamination and cleaning with saline (S), 2.5% NaOCl+saline (Na) or 2.5% NaOCl+17% EDTA+saline (NaE) and filled with: mineral trioxide aggregate (MTA), calcium-aluminate-cement (C), or C+collagen (Ccol) (n=13). The samples were evaluated for porosity, chemical composition, and bond strength. MTA porosity was lower than C (p=0.02) and higher than Ccol (p<0.001). P and NaE were similar (p=1.00), but higher than the other groups (p<0.001). MTA bond strength was similar to Ccol (p=0.777) and lower than C (p=0.028). P presented lower bond strength than the N (p<0.001); S and Na were similar to each other (p=0.969), but higher than P and lower than N (p<0.001). It was observed a predominance of mixed and cohesive failures. None of the samples showed Ca/P ratio values similar to human hydroxyapatite. This study showed that contamination with blood increased the materials porosity, but dentin cleaning with 2.5% NaOCl reduced this effect, and the collagen additive reduced the material porosity. Furthermore, blood contamination reduced the materials bond strength, and cleaning with saline or 2.5% NaOCl diminished this effect.

Resumo As amostras de raízes bovinas foram divididas em: sem contaminação (N); contaminação sanguínea (P); contaminação sanguínea e limpeza com soro fisiológico (S), 2,5% NaOCl+soro fisiológico (Na) ou 2,5% NaOCl+17%EDTA+soro fisiológico (NaE) e preenchido com: agregado de trióxido mineral (MTA), cimento de aluminato de cálcio (C), ou C+colágeno (Ccol) (n=13). A porosidade do MTA foi menor que C (p=0,02) e maior que Ccol (p<0,001). P e NaE foram semelhantes (p=1,00), mas superiores aos demais grupos (p<0,001). A resistência de união do MTA foi semelhante ao Ccol (p=0,777) e inferior ao C (p=0,028). P apresentou menor resistência de união que o N (p<0,001); S e Na foram semelhantes entre si (p=0,969), porém maiores que P e menores que N (p<0,001). Este estudo mostrou que a contaminação com sangue aumentou a porosidade dos cimentos, mas a limpeza da dentina com NaOCl 2,5% reduziu esse efeito, e o aditivo de colágeno reduziu a porosidade dos cimentos. Além disso, a contaminação sanguínea reduziu a resistência de união dos cimentos e a limpeza com solução salina ou NaOCl 2,5% diminuiu esse efeito.

Abstract The main objective of this study was to evaluate the biometric relationships between the species Bagre bagre, Lutjanus synagris and Nebris microps and their otoliths. The relationship between the size of the otolith (length and weight) and the size of the fish (standard length and total weight) was determined using the linear regression model (y = a + bx). For the morphological description, the otoliths of three specimens were selected by standard length class (10mm). The morphological characters analyzed were chosen according to traditional literature. Three hundred eight specimens of B. bagre, 200 of L. synagris and 237 of N. microps were analyzed. Throughout the collection period, the source of the capture of individuals was the municipality of Raposa. The linear correlations for fish and otolith length for B. bagre were 0.9129 and 0.9652, respectively. For L. synagris, the coefficients were 0.8634 and 0.8672, while for N. microps, 0.9597 and 0.8636, respectively. The morphological classification of L. synagris and N. microps is of the Saggita type, and the B. bagre species is of the Lapillus type. From the data presented here, it is possible to observe that otolith morphometric and morphological data can serve as a parameter to estimate the relationship between the fish and the otolith in terms of its biomass and the length of an individual and a population.

Resumo O objetivo principal deste estudo foi avaliar as relações biométricas entre as espécies Bagre bagre, Lutjanus synagris e Nebris microps e seus otólitos. A relação entre o tamanho do otólito (comprimento e peso) e o tamanho do peixe (comprimento padrão e peso total) foi determinada através do modelo de regressão linear (y = a + bx). Para a descrição morfológica, os otólitos de três espécimes foram selecionados por classe de comprimento padrão (10mm). Os caracteres morfológicos analisados foram escolhidos de acordo com a literatura tradicional. Foram analisados trezentos e oito exemplares de B. bagre, 200 de L. synagris e 237 de N. microps. Durante todo o período de coleta, a fonte de captura dos indivíduos foi o município de Raposa. As correlações lineares para peixes e comprimento de otólitos para B. bagre foram 0,9129 e 0,9652, respectivamente. Para L. synagris, os coeficientes foram 0,8634 e 0,8672, enquanto para N. microps, 0,9597 e 0,8636, respectivamente. A classificação morfológica de L. synagris e N. microps é do tipo Saggita, e da espécie B. bagre é do tipo Lapillus. A partir dos resultados aqui apresentados é possível observar que os dados morfométricos e morfológicos dos otólitos podem servir de parâmetro para estimar a relação entre o peixe e o otólito em termos de sua biomassa e do comprimento de um indivíduo e de uma população.

RESUMO Introdução: Os direitos laborais da mulher grávida são um tema de relevo para os médicos que acompanham a gestação, bem como para os Médicos do Trabalho. Para que estes possam garantir as melhores condições de segurança laboral a este grupo vulnerável, é importante estarem a par das leis de trabalho. A multidisciplinaridade entre médicos assistentes do seguimento da gestação e Médicos do Trabalho pode constituir uma importante aliança na identificação de riscos laborais específicos e posterior orientação da trabalhadora. Metodologia: Trata-se de uma revisão narrativa da legislação portuguesa realizada em novembro de 2022, nomeadamente do Código do Trabalho Português, complementado com o Guia Prático do Subsídio de Riscos Específicos, do Instituto da Segurança Social, I.P. Conteúdo: As trabalhadoras grávidas devem ser consideradas um grupo com particularidades em relação a riscos específicos e devem ser tomadas medidas no que toca à sua Saúde e Segurança, sob diversos pontos de vista, não as desfavorecendo no mercado de trabalho e não afetando as diretivas de igualdade de tratamento entre homens e mulheres. É direito da mulher grávida que as suas condições de trabalho sejam devidamente avaliadas e, se for caso disso, adaptadas pela entidade empregadora, de modo a garantir a sua segurança e do feto. Conclusão: É importante que os profissionais de saúde estejam devidamente informados sobre os direitos laborais das grávidas. A colaboração do Médico do Trabalho é essencial na identificação fidedigna de riscos específicos laborais, de modo que a gravidez decorra sem exposição a estes riscos, e que, caso ocorram, sejam devidamente minimizados ou orientados.

ABSTRACT Introduction: The labor rights of pregnant women are of great relevance for the doctors that follow the pregnancy, as well as for the Occupational Health doctors. For them to be able to ensure work safety for this vulnerable group, they need to have a good understanding of the work laws. The multidisciplinarity between the two medical specialties can constitute an important alliance in the identification of specific labor risks, and the orientation of the worker. Methodology: This is an review of the portuguese legislation conducted in november of 2022, regarding the Portuguese Work Code, complemented by the Practical Guide of the Subsidy of Specific Risks, from the Social Security Institute. Contents: Pregnant workers must be considered a susceptible group for specific risks and there must be taken measures regarding their health and security, from various points of view. This cannot result in disadvantage in the work market and it cannot affect the equality of treatment between men and women. It’s the pregnant women right that the work conditions are evaluated, and, if needed, adapted by the employer, so the safety of the mother and the fetus is guaranteed. Discussion and Conclusions: It’s important for health professionals to be informed about the work rights of pregnant women. The collaboration with Occupational Health professionals is essential in the right identification of specific work risks, so that the pregnancy can proceed without exposured to such risks and, in the case of such exposure, they can be rightly adjusted.

Abstract Background Some studies have suggested the HLA-B27 gene may protect against some infections, as well as it could play a benefit role on the viral clearance, including hepatitis C and HIV. However, there is lack of SARS-CoV-2 pandemic data in spondyloarthritis (SpA) patients. Aim To evaluate the impact of HLA-B27 gene positivity on the susceptibility and severity of COVID-19 and disease activity in axial SpA patients. Methods The ReumaCoV-Brasil is a multicenter, observational, prospective cohort designed to monitor immunemediated rheumatic diseases patients during SARS-CoV-2 pandemic in Brazil. Axial SpA patients, according to the ASAS classification criteria (2009), and only those with known HLA-B27 status, were included in this ReumaCov-Brasil's subanalysis. After pairing them to sex and age, they were divided in two groups: with (cases) and without (control group) COVID-19 diagnosis. Other immunodeficiency diseases, past organ or bone marrow transplantation, neoplasms and current chemotherapy were excluded. Demographic data, managing of COVID-19 (diagnosis, treatment, and outcomes, including hospitalization, mechanical ventilation, and death), comorbidities, clinical details (disease activity and concomitant medication) were collected using the Research Electronic Data Capture (REDCap) database. Data are presented as descriptive analysis and multiple regression models, using SPSS program, version 20. P level was set as 5%. Results From May 24th, 2020 to Jan 24th, 2021, a total of 153 axial SpA patients were included, of whom 85 (55.5%) with COVID-19 and 68 (44.4%) without COVID-19. Most of them were men (N = 92; 60.1%) with mean age of 44.0 ± 11.1 years and long-term disease (11.7 ± 9.9 years). Regarding the HLA-B27 status, 112 (73.2%) patients tested positive. There were no significant statistical differences concerning social distancing, smoking, BMI (body mass index), waist circumference and comorbidities. Regarding biological DMARDs, 110 (71.8%) were on TNF inhibitors and 14 (9.15%) on IL-17 antagonists. Comparing those patients with and without COVID-19, the HLA-B27 positivity was not different between groups (n = 64, 75.3% vs. n = 48, 48%, respectively; p = 0.514). In addition, disease activity was similar before and after the infection. Interestingly, no new episodes of arthritis, enthesitis or extra-musculoskeletal manifestations were reported after the COVID-19. The mean time from the first symptoms to hospitalization was 7.1 ± 3.4 days, and although the number of hospitalization days was numerically higher in the B27 positive group, no statistically significant difference was observed (5.7 ± 4.11 for B27 negative patients and 13.5 ± 14.8 for B27 positive patients; p = 0.594). Only one HLA-B27 negative patient died. No significant difference was found regarding concomitant medications, including conventional or biologic DMARDs between the groups. Conclusions No significant difference of COVID-19 frequency rate was observed in patients with axial SpA regarding the HLA-B27 positivity, suggesting a lack of protective effect with SARS-CoV-2 infection. In addition, the disease activity was similar before and after the infection. Trial registration This study was approved by the Brazilian Committee of Ethics in Human Research (CONEP), CAAE 30186820.2.1001.8807, and was registered at the Brazilian Registry of Clinical Trials – REBEC, RBR-33YTQC. All patients read and signed the informed consent form before inclusion.

ABSTRACT The study of the concentration dynamics of a pollutant substance in a fluid is a classic problem of fluid mechanics given by the transport equation u t + cu x = 0, where u = u(x,t) denotes the pollutant concentration along a horizontal pipe of a fixed cross-section in the positive x direction at he time t > 0 and c represents the fluid propagation velocity. In view of that, the velocity of propagation of the fluid is a physical quantity, obtained, generally in an approximate form, which makes such quantity uncertain. In this paper, we propose to obtain the concentration when the constant c represents the fuzzy set. The concentration was obtained by using the Zadeh’s Extension Principle. Through the concentration obtained, we analyze the influence of uncertainty on the fluid propagation velocity in the concentration dynamics and explore possible practial applications in case-studies of engineering, environmental and soil sciences.

Resumo Este é o primeiro trabalho sobre análise da complexidade e heterogeneidade de habitats do Pantanal. O Pantanal é constituído por um mosaico de ambientes com características peculiares, sendo importante a avaliação e o monitoramento dessa área voltado para a conservação da biodiversidade. O objetivo do estudo é mensurar de forma indireta a complexidade e a heterogeneidade do mosaico de habitats os quais formam as sub-regiões do Pantanal, por meio do sensoriamento remoto. Foram obtidas, gratuitamente, imagens de índice de vegetação por diferença normalizada (NDVI) do sensor MODIS e calculado o valor de média (complexidade) e desvio padrão (heterogeneidade) para cada sub-região do Pantanal, para os anos de 2000, 2008 e 2015. Os pantanais de Poconé, Canoeira, Paraguai e Aquidauana são as regiões que apresentaram os maiores valores de complexidade (NDVI médio), variando entre 0.69 a 0.64 para os anos avaliados. Maior heterogeneidade (NDVI desvio padrão) foi observada na sub-região pantaneira do Tuiuiú, sendo o valor para os anos de 2000 e 2015 igual a 0.19 e para o ano de 2008 o valor de 0.21, o que implica que a região tem a maior heterogeneidade horizontal quando comparada com as demais sub-regiões. Constata-se que o uso de NDVI na estimativa de parâmetros da paisagem é uma ferramenta eficiente para o reconhecimento e monitoramento da complexidade e heterogeneidade de habitats do Pantanal, replicável em outras regiões.

Abstract This is the first report on analysis of habitat complexity and heterogeneity of the Pantanal wetland. The Pantanal encompasses a peculiar mosaic of environments, being important to evaluate and monitor this area concerning conservation of biodiversity. Our objective was to indirectly measure the habitat complexity and heterogeneity of the mosaic forming the sub-regions of the Pantanal, by means of remote sensing. We obtained free images of Normalized Difference Vegetation Index (NDVI) from the sensor MODIS and calculated the mean value (complexity) and standard deviation (heterogeneity) for each sub-region in the years 2000, 2008 and 2015. The sub-regions of Poconé, Canoeira, Paraguai and Aquidauana presented the highest values of complexity (mean NDVI), between 0.69 and 0.64 in the evaluated years. The highest horizontal heterogeneity (NDVI standard deviation) was observed in the sub-region of Tuiuiú, with values of 0.19 in the years 2000 and 2015, and 0.21 in the year 2008. We concluded that the use of NDVI to estimate landscape parameters is an efficient tool for assessment and monitoring of the complexity and heterogeneity of the Pantanal habitats, applicable in other regions.

RESUMO: Atualmente, o biomonitoramento tem sido uma metodologia bastante adotada para se verificar o impacto ambiental das novas tecnologias no meio agrícola, com destaque para a entomofauna edáfica, que é tradicionalmente utilizada como bioindicadora nesse tipo de pesquisa. Assim, objetivou-se com este estudo investigar a variação da entomofauna edáfica em função da aplicação do herbicida glyphosate em cultivos de soja Roundup Ready. O experimento foi realizado em Coimbra, MG, nas safras agrícolas de 2007/2008 e 2008/2009. Utilizou-se o delineamento experimental em blocos casualizados com cinco repetições. Os tratamentos estudados foram: soja não transgênica com capina mecânica das plantas daninhas; soja transgênica com capina mecânica das plantas daninhas; soja transgênica com uma aplicação de glyphosate; e soja transgênica com três aplicações de glyphosate. As populações da entomofauna edáfica foram amostradas ao longo dos dois cultivos. A inserção do gene de tolerância ao herbicida glyphosate não afetou a riqueza e a abundância de artrópodes do interior do solo. A riqueza dos artrópodes foi reduzida nos tratamentos que receberam uma e três aplicações de glyphosate. A aplicação de glyphosate na soja transgênica reduziu a densidade do ácaro predador Galumnidae (Acari); das formigas predadoras Neivamyrmex sp. (Hymenoptera: Formicidae) e Solenopsis sp. (Hymenoptera: Formicidae); e dos colêmbolos Entomobryidae (Collembola), Hypogastrura sp. (Collembola: Hypogastruridae) e Onychiuridae (Collembola). Diante disso, torna-se essencial atender às recomendações de uso do herbicida glyphosate e adotar boas práticas culturais que favoreçam a biodegradação de pesticidas, para assim contribuir com a redução do potencial toxicológico do glyphosate sobre a entomofauna edáfica.

ABSTRACT: Currently, biomonitoring is a methodology used to verify the environmental impact of new technologies in the agricultural environment, highlighting edaphic entomofauna that is traditionally used as a bioindicator in this sort of research. Therefore, the objective of this study was to investigate the edaphic entomofauna variation depending on glyphosate application in Roundup Ready soybeans. The experiment was carried out in Coimbra, MG during the 2007/2008 and 2008/2009 cropping seasons. The experimental design was a randomized block design with five replications. The treatments were: non-transgenic soybean with mechanical weeding of weeds; transgenic soybean with mechanical weeding of weeds; transgenic soybean with one glyphosate application and transgenic soybean with three glyphosate applications. The populations of the edaphic entomofauna were sampled during two crops. The insertion of the glyphosate tolerance gene did not affect the richness and the abundance of arthropods in the soil. The arthropod richness was reduced in treatments where glyphosate was applied one and three times. The glyphosate application in transgenic soybean reduced the density of the predatory mite Galumnidae (Acari); predator ants Neivamyrmex sp. (Hymenoptera: Formicidae) and Solenopsis sp. (Hymenoptera: Formicidae); and springtails Entomobryidae (Collembola), Hypogastrura sp. (Collembola: Hypogastruridae) and Onychiuridae (Collembola). Therefore, it is essential to follow the use recommendations of the herbicide glyphosate and adopt good agricultural practices that promote pesticide biodegradation, thereby contributing to the reduction of the toxicological potential of glyphosate on the edaphic entomofauna.

Maternal smoking is a risk factor for progeny obesity. We have previously shown, in a rat model of neonatal tobacco smoke exposure, a mild increase in food intake and a considerable increase in visceral adiposity in the adult offspring. Males also had secondary hyperthyroidism, while females had only higher T4. Since brown adipose tissue (BAT) hypofunction is related to obesity, here we tested the hypothesis that higher levels of thyroid hormones are not functional in BAT, suggesting a lower metabolic rate. We evaluated autonomic nerve activity in BAT and its function in adult rats that were exposed to tobacco smoke during lactation. At birth, litters were adjusted to 3 male and 3 female pups/litter. From postnatal day (PND) 3 to 21, Wistar lactating rats and their pups were divided into SE group, smoke-exposed in a cigarette smoking machine (4 times/day) and C group, exposed to filtered air. Offspring were sacrificed at PND180. Adult SE rats of both genders had lower interscapular BAT autonomic nervous system activity, with higher BAT mass but no change in morphology. BAT UCP1 and CPT1a protein levels were decreased in the SE groups of both genders. Male SE rats had lower β3-AR, TRα1, and TRβ1 expression while females showed lower PGC1α expression. BAT Dio2 mRNA and hypothalamic POMC and MC4R levels were similar between groups. Hypothalamic pAMPK level was higher in SE males and lower in SE females. Thus, neonatal cigarette smoke exposure induces lower BAT thermogenic capacity, which can be obesogenic at adulthood.

Despite the various standard non-linear measurements used in autonomic modulation (AM) assessments usually being applied to long time-series, such analyses can sometimes be applied to shorter term series. To overcome this disadvantage, chaotic global methods were formulated by putting together heart rate variability (HRV) linear methods. Chaos provides information about vegetative function control related to cardiovascular risks. Applying this method can be useful to investigate the complexity of the health condition after resistance training protocols, as a therapeutic intervention in AM in metabolic syndrome individuals (MetS). This study aimed to compare the effects of two resistance training programs (conventional vs functional) in MetS using nonlinear analysis of AM. MetS subjects (n=50) of both sexes aged 40 to 60 years were randomly divided into two programs; a group of 12 people served as a control group. Both groups performed 30 sessions of training. AM was assessed in the chaos domain by chaotic global techniques. The main results showed that both resistance training, functional and conventional, increased chaos when compared to the control group, respectively, observed by chaotic forward parameter (CFP)1 (13.9±17.9 vs 12.8±14.4 vs -2.23±7.96; P≤0.05) and CFP3 (15.4±19.8 vs 21.9±13.2 vs -4.82±11.4; P≤0.05). In addition, 30 sessions of both resistance programs increased chaos, and non-linear analysis enabled discrimination of AM after interventions when compared to the control group.

Early weaning (EW) leads to overweight, visceral obesity, hyperleptinemia, and insulin resistance in adulthood. Treatment with Ilex paraguariensis (yerba mate) improves obesity and insulin resistance in these animals. Here, we evaluated the effects of chronic treatment with yerba mate on the redox balance and liver morphology of overweight early-weaned rats. To induce EW, we wrapped the dams with bandages to interrupt milk access during the last 3 days of lactation. Control pups (C) had free access to maternal milk for the full 21 days of lactation. On postnatal day (PN) 150, EW offspring were subdivided into the EW+YM group, which received the aqueous extract of yerba mate (1 g/kg bw by gavage once a day for 30 days) and the EW group, which received water by gavage for the same period. All rats were euthanized on PN180. The EW group showed higher bound carbonyl (a marker of total protein oxidation), higher TBARS levels (a marker of lipid peroxidation), and lower superoxide dismutase (SOD) activity in liver tissue than the C group, as well as higher triglyceride content and microsteatosis. In plasma, the EW offspring showed higher TBARS levels. One month of yerba mate treatment normalized these parameters. Thus, we have shown evidence that yerba mate improved antioxidant defenses and mitigated liver dysfunction in overweight adult rats that were weaned prematurely.

ABSTRACT Single crystals of 1,3-bis(cyanomethoxy)calix[4]arene (1) were grown from Chloroform/Methanol mixture and these were nanodecorated with colloidal gold nanoparticles (AuNps). The single crystals were then characterized by single-crystal X-ray diffraction (XRD) and Scanning Electronic Microscopy (SEM). The nanodecorated crystals were characterized by UV-Visible Absorption Spectroscopy, Transmission Electronic Microscopy (TEM) and X-ray Photoelectron Spectroscopy (XPS). In this work, it is shown that the stabilization of the nanoparticles occurs through of the interactions of these with the nitrile group, maintaining their shape and size.

Se condujo una investigación en Venezuela con la finalidad de conocer algunos aspectos epidemiológicos sobre la presencia de Cystoisospora suis en 67 granjas porcinas intensivas. Para la determinación de la carga parasitaria se seleccionaron 572 camadas con signos de diarrea, así como 1.712 muestras fecales de cerdos adultos. Las muestras se cultivaron en dicromato de potasio al 2,5% y posteriormente se procesaron mediante una técnica copro-parasitológica. Además, en cada granja se aplicó una encuesta epidemiológica. El protozoario se encontró en 55 granjas (82,1%) y 210 camadas (36,7%). Al referirlo a camadas, se observaron ooquistes en lechones menores de tres días de edad, lo que podría indicar la existencia de rutas alternativas de la infección. En cerdos adultos se encontró correlación significativa (rho = 0,35; P < 0,05) entre la excreción de ooquistes en lechones y en madres, lo que sugiere que estas podrían actuar como fuentes de infección. Se constató correlación entre el número de partos de la cerda y la prevalencia en camadas y cerdas lactantes (P < 0,05), pues, a mayor número de partos, disminuye la prevalencia. Probablemente estos hallazgos están asociados con mecanismos inmunológicos desconocidos. El tamaño de la granja no afectó la presencia del parásito; sin embargo, las granjas con pisos plásticos mostraron mayor control de la infección. Se concluye que algunos mecanismos inmunológicos, aún sin dilucidar, podrían estar involucrados en la cadena de transmisión del protozoario, los cuales podrían jugar un papel importante en el desarrollo de la cystoisosporosis porcina.

It was carried out an investigation in Venezuela with the aim of studying the epidemiological aspects of Cystoisospora suis in intensive swine herds. Sixty-seven intensive swine herds were included. For parasite determination 572 litters with signs of diarrhea, as well as 1,712 faecal samples from mature pigs were selected. Stool samples were cultured in a 2.5% potassium dichromate solution and later processed by copro-parasitological technique. Epidemiological surveys were applied on each farm. The results indicated that C. suis was observed in 55 herds (82.1%) and 210 litters (36.7%). Regarding to litters, oocysts were observed in piglets less than three days of life, which could indicate the existence of alternative infection way. Regarding to mature pigs, there was a significant correlation (rho = 0.35; P < 0.05) among oocysts excretion in piglets and sows, suggesting that sows may act as infection sources. Sows parity was statistically correlated with the prevalence values in litters as in lactating sows (P < 0.05). This might indicate that as parity increase, prevalence decreases in these groups. Probably, these findings are associated with unknown immunologic mechanisms. The herd size did not affect the presence of the parasite, however, farms with plastic floors showed greater control of the infection. It is concluded that non elucidated immunologic mechanisms might be involved in the protozoa transmission cycle and play an important role in the development of porcine cystoisosporosis.