Diagnosis of fasciolosis antibodies in Brazilian cattle through ELISA employing both native and recombinant antigens

Bovine fasciolosis is a parasitic disease with a global reach. Coprological based on egg detection in fecal samples and liver inspection to evaluate the presence of the parasite is currently the gold standard for diagnosing chronic fasciolosis in cattle. However, these techniques are labor-intensive and ineffective during the acute phase of the disease. Serodiagnosis using native and recombinant antigens has become an interesting alternative in efforts to identify cattle fasciolosis. We evaluated cattle from abattoir (n = 139) and farms (n = 500) through liver inspection and coprological examination, respectively. Our laboratory team optimized and validated enzyme-linked immunosorbent assay tests based on somatic antigen, excretory/secretory proteins, and the recombinant antigen cathepsin L-1 to detect serum antibodies against fasciolosis in cattle. For animals from abattoir, 10 were positive for fasciolosis according to liver inspection. Both FhES and FhrCL-1 presented an area under the receiver operating characteristic (AUROC) curve of 0.80, with a sensitivity of 0.80 (95% CI: 0.46-0.95) and 0.70 (95% CI: 0.38-0.90) and specificity of 0.81 (95% CI: 0.73-0.87) and 0.87 (95% CI: 0.80-0.92), respectively. For those cattle from farms, 28 were positive only for fasciolosis according to coprological examination. In this scenario, FhES gave the best performance, with an AUROC of 0.84, sensitivity of 0.79 (95% CI: 0.60-0.90), and specificity of 0.86 (95% CI: 0.82-0.89). In conclusion, our study highlights the potential of serodiagnosis for accurately screening cattle fasciolosis. The promising sensitivity and specificity values of FhES when compared to liver inspection or coprological examination enhance its importance for cattle fasciolosis diagnosis.

IMPORTANCE

The aim of this article was to identify antibodies against fasciolosis in cattle in Brazil. The methodology was reproduced in our laboratory and applied for the first time to the Brazilian cattle herd. The antigens tested can be used as a screening test and thus speed up the diagnosis of bovine fascioliasis.

Serological diagnosis of fasciolosis (Fasciola hepatica) in humans, cattle, and sheep: a meta-analysis

Fasciola hepatica can cause problems in both animals and humans. Fasciolosis can be diagnosed through the indirect ELISA immunodiagnostic test. Serological diagnosis of Fasciola is based on recombinant antigens secreted by this worm. We used PubMed and Google Scholar databases to review the published literature on 'antigens with immunogenic potential' used in serological tests to identify antibodies against F. hepatica in humans, cattle, and sheep. Studies that investigated diagnostic tests with common reference standards were included in the sensitivity and/or specificity bivariate meta-analysis. In the quality and susceptibility to bias analysis of the 33 included studies, 26 fulfilled at least six (75%) of the eight QUADAS criteria and were considered good-quality papers. We found that most of the studies used native excretory-secretory antigens and recombinant cathepsin in ELISA tests for serological diagnosis of fascioliasis in humans, cattle, and sheep. The meta-analysis revealed that all antigens demonstrated good accuracy. The best results in terms of sensitivity [0.931-2.5% confidence interval (CI) and 0.985-97.5% CI] and specificity (0.959-2.5% CI and 0.997-97.5% CI) were found in human FhES. FhrCL-1, FhES, and FhrSAP-2 antigens gave the best results for the serum diagnosis of human and animal fasciolosis.

Epidemiological Survey and Confirmation of Autochthonous Cases of Bovine Fasciolosis in the Serrana Mesoregion of Santa Catarina, Brazil

Fasciola hepatica is reported as a trematode of great importance, causing fasciolosis, one of the most neglected zoonotic parasitic diseases in the world. In Brazil, potential losses of around US$ 210 million per year were calculated, with bovine fasciolosis alone. The State of Santa Catarina is located in the South Region of Brazil, with a herd of more than 4 million ruminants. The Serrana Mesoregion, historically free of fasciolosis, is composed of 30 municipalities, which have a consolidated agricultural tradition, mainly in extensive ruminant livestock. The objective of the present work was to investigate the occurrence and distribution of autochthonous cases of bovine fasciolosis in the region. For this, different analyzes were carried out in rural properties from eight municipalities, and in three slaughterhouses under the State Inspection Service (SIE), which received animals from all the Serrana Mesoregion. The rural properties were randomly selected, and up to 20 fecal samples were collected from random cattle older than 1 year, for analysis by coproparasitological sedimentation test. The traceability records of the positives were checked, for identifying autochthonous cases. Additionally, the tracking data of cattle slaughtered between the years of 2018 and 2021, which presented liver condemnations, were analyzed for defining autochthonous cases of bovine fasciolosis. In total, there were fecal samplings in 106 farms, with 1,927 tested cattle. From these, 178 (9.2%) were positive and autochthonous, but the overall result did not reflect the heterogeneity found between the evaluated municipalities. During the analyzed period, 11,556 cattle were slaughtered, with 1,744 (15.1%) liver condemnations due to fasciolosis in animals that never left the Serrana Mesoregion. The present study confirmed the presence of autochthonous cases of bovine fasciolosis in municipalities of the Serrana Mesoregion, and verified a high rate of positivity in animals slaughtered in the regional slaughterhouses. When the prevalence of bovine fasciolosis in vivo was compared with the postmortem positivity index in five municipalities, the results disagreed in four municipalities (p-value < 0.05), emphasizing the need for field investigation for the better understanding of the distribution and frequency of the parasitosis.

Razão de prevalência e distribuição espacial de fasciolose bovina em propriedades de Orleans, Santa Catarina

A fasciolose é uma zoonose com quadro subclínico e que leva a perdas econômicas na criação de bovinos. Casos da doença foram identificados em matadouro localizado em Orleans, Santa Catarina, Brasil. Para identificação de casos e cálculo do soro prevalência de fasciolose bovina em propriedades rurais do município de Orleans foi realizado um teste de ELISA (enzyme-linked immunosorbent assay). Foi elaborado um mapa para análise da distribuição dos casos de fasciolose no município. Foram aplicados questionários, com o objetivo de identificar o tipo de manejo realizado por propriedade, fatores associados e possíveis medidas de intervenção a serem adotadas. Através de testes estatísticos, a ocorrência da fasciolose foi comparada ao tipo de manejo e criação dos animais além de dados ambientais. Dos animais testados, 29,78% apresentaram resultado soropositivo para fasciolose. Das 35 propriedades visitadas, 24 possuíram bovinos com soropositividade para fasciolose. Houve significância estatística para as variáveis “local de compra” e “tipo de sistema produtivo”. Esses resultados são importantes para que médicos veterinários e principalmente os produtores conheçam a situação sanitária da propriedade e assim promovam medidas preventivas.

Virulence factors, antimicrobial resistance, and plasmid content of Escherichia coli isolated in swine commercial farms

Virulence factors and antimicrobial resistance patterns of Escherichia coli isolates were evaluated. A total of 80 E. coli isolates were evaluated, being 64 from clinical samples (intestinal content and fragments of organs from diarrheic piglets), seven from feces of clinically healthy piglets and sows, and nine environmental samples (five from facilities, two from feed, one from insect, and one from waste). Molecular characterization was performed by PCR detection of fimbriae and toxin genes and plasmid content determination. The isolates were also characterized according to their resistance or sensitivity to the following drugs: ampicillin, trimethoprim:sulfamethoxazole, tetracycline, amikacine, colistin, norfloxacin, florfenicol, enrofloxacin, cefalexin, trimethoprim, neomycin, chloramphenicol, and gentamicin. From 80 E. coli isolates, 53.8% were classified as enterotoxigenic E. coli (ETEC), 2.5% were shiga toxin-producing E. coli (STEC), and 43.8% showed a non specific pattern and were unclassified. One fecal isolate from non-diarrheic piglet was classified as ETEC by PCR. Clinical isolates showed resistance mainly for tetracycline and trimethoprim:sulfamethoxazole. Plasmidial DNA was observed in 70 isolates, being 78.5% of clinical isolates, 8.57% of non-diarrheic feces, and 12.8% of environment.

Identificação diferencial de Rhodococcus equi e Dietzia maris em bubalinos

Foram analisados 24 isolados bacterianos oriundos de leite e pele de búfalas (Bubalus bubalis), os quais foram previamente identificados como Rhodococcus equi com o auxílio de fenotipia concisa. Testes fenotípicos complementares e ferramentas moleculares foram utilizados com o objetivo de caracterizar esses isolados, bem como diferenciá-los de outros microrganismos intimamente relacionados. Observaram-se três fenótipos distintos, porém a identificação dos isolados foi inconclusiva. Apenas um dos isolados foi comprovado como sendo R. equi com a realização da PCR espécie-específica, sequenciamento e análise dos fragmentos de DNA. Os demais isolados só foram identificados pelo sequenciamento de fragmento do gene que codifica a região 16S do rRNA universal de bactérias, indicando tratar-se de Dietzia maris. O perfil de susceptibilidade aos antimicrobianos revelou maior resistência dos isolados de D. maris para oxacilina (96%) e rifampicina (87%). O isolado de R. equi apresentou resistência à amicacina, oxacilina, penicilina, rifampicina e tetraciclina. Alerta-se para o risco da incorreta identificação dos isolados baseados em testes fenotípicos concisos e para a necessidade de utilização de testes complementares para diferenciação entre R. equi e D. maris.

Virulence factors and antimicrobial resistance of escherichia coli isolated from urinary tract of swine in southern of Brazil

The present study determined the molecular and resistance patterns of E. coli isolates from urinary tract of swine in Southern of Brazil. Molecular characterization of urinary vesicle samples was performed by PCR detection of virulence factors from ETEC, STEC and UPEC. From a total of 82 E. coli isolates, 34 (38.63%) harbored one or more virulence factors. The frequency of virulence factors genes detected by PCR were: pap (10.97%), hlyA (10.97%), iha (9.75%), lt (8.53%), sta (7.31%) sfa (6.09%), f4 (4.87%), f5 (4.87%), stb (4.87%), f6 (1.21%) and f41 (1.21%). Isolates were resistant to penicillin (95.12%), lincomycin (93.9%), erythromycin (92.68%), tetracycline (90.24%), amoxicillin (82.92%), ampicillin (74.39%), josamycin (79.26%), norfloxacin (58.53%), enrofloxacin (57.31%), gentamicin (39.02%), neomycin (37.8%), apramycin (30.48%), colistine (30.48%) and cefalexin (6.09%). A number of 32 (39.02%) E. coli isolates harbored plasmids.

Mediterranean diet pyramid: a cultural model for healthy eating

We present a food pyramid that reflects Mediterranean dietary traditions, which historically have been associated with good health. This Mediterranean diet pyramid is based on food patterns typical of Crete, much of the rest of Greece, and southern Italy in the early 1960s, where adult life expectancy was among the highest in the world and rates of coronary heart disease, certain cancers, and other diet-related chronic diseases were among the lowest. Work in the field or kitchen resulted in a lifestyle that included regular physical activity and was associated with low rates of obesity. The diet is characterized by abundant plant foods (fruit, vegetables, breads, other forms of cereals, potatoes, beans, nuts, and seeds), fresh fruit as the typical daily dessert, olive oil as the principal source of fat, dairy products (principally cheese and yogurt), and fish and poultry consumed in low to moderate amounts, zero to four eggs consumed weekly, red meat consumed in low amounts, and wine consumed in low to moderate amounts, normally with meals. This diet is low in saturated fat (< or = 7-8% of energy), with total fat ranging from < 25% to > 35% of energy throughout the region. The pyramid describes a dietary pattern that is attractive for its famous palatability as well as for its health benefits.