ABSTRACT: Cattle are considered intermediate hosts of Sarcocystis, which can cause clinical signs and lower performance in the acute phase of infection. Sarcocystis spp. are usually not visible to the naked eye during the post mortem inspection. Moreover, fresh microscopic examination and transmission electron microscopy techniques are difficult to apply to large samples. Therefore, extensive studies on Sarcocystis infection in cattle using molecular and serological methods are required. Here, we investigated Sarcocystis spp. infection in cattle using fresh microscopic examination and polymerase chain reaction of myocardium samples and compared the results with the presence of antibodies against Sarcocystis spp. in corresponding serum samples detected using indirect fluorescent antibody test. Microscopic Sarcocystis were observed in 100% of the myocardial samples, and Sarcocystis DNA was present in 86% (43/50) of these samples. Antibodies against Sarcocystis spp. were detected in 96% (48/50) and 80% (40/50) of the serum samples at 1:25 and 1:200 dilutions, respectively. The three associated methods (fresh microscopic examination, PCR and serology) showed good sensitivity and detection for Sarcocystis spp. compared with fresh microscopic examination (only), and they may facilitate diagnosis in live animals on a large scale as well as monitoring of the herd status.

RESUMO: Os bovinos são considerados hospedeiros intermediários de Sarcocystis, podendo causar sinais clínicos e menor desempenho na fase aguda da infecção. Sarcocystis spp. geralmente não são visíveis a olho nu durante a inspeção post mortem. Além disso, o exame microscópico a fresco e as técnicas de microscopia eletrônica de transmissão são difíceis de aplicar a uma amostras de grande tamanho. Portanto, são necessários extensos estudos sobre a infecção por Sarcocystis em bovinos usando métodos moleculares e sorológicos. Aqui, investigamos a infecção de Sarcocystis spp. em bovinos por meio de exame microscópico a fresco e reação em cadeia da polimerase de amostras de miocárdio e comparado os resultados com a presença de anticorpos contra Sarcocystis spp. em amostras de soro correspondentes detectadas usando o teste de anticorpos fluorescentes indiretos. Sarcocistos microscópicos foram observados em 100% das amostras de miocárdio, e o DNA de Sarcocystis estava presente em 86% (43/50) dessas amostras. Anticorpos contra Sarcocystis spp. foram detectados em 96% (48/50) e 80% (40/50) das amostras de soro nas diluições 1:25 e 1:200, respectivamente. Os três métodos associados (exame microscópico a fresco, PCR e sorologia) mostraram boa sensibilidade e detecção para Sarcocystis spp. em comparação com o exame microscópico fresco (apenas) e podem facilitar o diagnóstico em animais vivos em larga escala, bem como o monitoramento do status do rebanho.

Abstract: We define a new lifetime model based on compounding the Lindley and Nadarajah-Haghighi distributions. The proposed distribution is very competitive to other lifetime models. Some of its mathematical properties are investigated including generating function, mean residual life, moments, Bonferroni and Lorenz curves and mean deviations. We discuss the estimation of the model parameters by maximum likelihood. We provide a simulation study and two applications to real data for illustrative purposes. We prove empirically that the new distribution yields good fits to both data sets, and it can be a useful alternative for other classical lifetime models.

Abstract We propose a new lifetime model called the exponentiated power generalized Weibull (EPGW) distribution, which is obtained from the exponentiated family applied to the power generalized Weibull (PGW) distribution. It can also be derived from a power transform on an exponentiated Nadarajah-Haghighi random variable. Since several structural properties of the PGW distribution have not been studied, they can be obtained from those of the EPGW distribution. The model is very flexible for modeling all common types of hazard rate functions. It is a very competitive model to the well-known Weibull, exponentiated exponential and exponentiated Weibull distributions, among others. We also give a physical motivation for the new distribution if the power parameter is an integer. Some of its mathematical properties are investigated. We discuss estimation of the model parameters by maximum likelihood and provide two applications to real data. A simulation study is performed in order to examine the accuracy of the maximum likelihood estimators of the model parameters.

RESUMO: A colibacilose é a principal causa infecciosa de condenação total de carcaça em frangos de corte no sul do Brasil. Esse trabalho tem por objetivo determinar o grau de concordância entre a condenação total por colibacilose de frangos de corte abatidos em estabelecimento sob Serviço de Inspeção Federal (SIF) com o diagnóstico anatomopatológico e bacteriológico. O estudo foi realizado com 45 frangos de corte condenados totalmente por colibacilose (caso) e seus respectivos 45 controles (frangos sem lesões). Em todos os frangos condenados pelo SIF havia lesões macroscópicas e, nos controles não se observou. Através do teste Kappa-Cohen´s essas duas variáveis apresentaram concordância quase perfeita. As aves condenadas apresentaram lesões em fígado (27/45); em fígado e sacos aéreos (11/45); em fígado e coração (2/45); fígado, sacos aéreos e coração (2/45); fígado, sacos aéreos e oviduto (1/45); fígado, sacos aéreos, coração e tecido subcutâneo (1/45); e fígado, sacos aéreos, oviduto e baço (1/45). Observou-se concordância quase perfeita entre condenação e lesão hepática. Histologicamente, em 41 casos e 12 controles observaram-se lesões, sendo os mais frequentes hepatite necrosante aleatória, bronquite fibrino-heterofílica, pericardite aguda e traqueíte linfoplasmocitária. Nas aves com hepatite identificou-se E. coli, Enterococcus sp. e Streptococcus sp. (10/38) e, nas aves com bronquite ou broncopneumonia isolou-se Escherichia coli e Staphylococcus coagulase positiva (9/14). O PCR em tempo real e a imuno-histoquímica para Mycoplasma gallisepticum e M. synoviae foram negativos. Nos casos de condenação total por colibacilose o fígado foi o principal órgão acometido, portanto, o critério de condenação deveria ser revisto, sugerindo condenação por hepatite nesses casos, já que outras bactérias podem causar hepatite, como foi demonstrado nesse estudo.

ABSTRACT: Colibacillosis is the main infectious cause of total carcass condemnation in broilers in southern Brazil. This study aims to determine the degree of agreement between the total carcass condemnation for colibacillosis in broilers slaughtered in establishments under Federal Inspection Service (SIF) with the pathological and bacteriological diagnosis. The study was conducted with 45 broilers totally condemned by colibacillosis (case) and theirs 45 respective controls (chickens without lesions). All broilers condemned had gross lesions and the controls had not. The Kappa-Cohen’s test showed that these two variables had almost perfect agreement. Broilers condemned showed lesions in liver (27/45); liver and air sacs (11/45); liver and heart (2/45); liver, heart and air sacs (2/45); liver, air sacs and oviduct (1/45); liver, air sacs, heart and subcutaneous (1/45); and liver, air sacs, oviduct and spleen (1/45). There is almost perfect agreement between carcass condemnation and liver damage. Histologically, in 41 cases and 12 controls were observed lesions, the most frequent diagnoses were random necrotizing hepatitis, fibrinous-heterophilic bronchitis, acute pericarditis and lymphoplasmacytic tracheitis. In hepatitis cases was isolated Escherichia coli, Enterococcus sp. and Streptococcus sp. (10/38) and in bronchitis or bronchopneumonia E. coli and coagulase positive Staphylococcus (9/14). The polymerse chain reaction (PCR) and immunohistochemistry (IHC) tests for Mycoplasma gallisepticum and M. synoviae were negative. In cases of total carcass condemnation by Colibacillosis the liver was the main organ affected. Therefore, the condemnation criteria should be revised, suggesting conviction for hepatitis in these cases, because other bacteria can cause hepatitis, as demonstrated in this study.

A micoplasmose aviária é causada por bactérias da família Mycoplasmataceae. Mycoplasma gallisepticum (MG) é a espécie mais patogênica e que tem a maior importância econômica para a produção avícola. Este estudo teve por objetivo utilizar a técnica de imuno-histoquímica (IHQ) como método de diagnóstico da infecção por MG em aves. No presente relato são descritos dois surtos de micoplasmose por MG em galinhas de subsistência. Clinicamente as aves apresentaram prostração, hiporexia, dificuldade respiratória, secreção nasal e ocular. Na necropsia foram observados secreção serosa, edema e deposição de cáseo em conjuntiva (7/10) e seios nasais (4/10), sacos aéreos espessados com espuma e cáseo (6/10); traqueia difusamente avermelhada (4/10); pulmões com pontos esbranquiçados de 0,5cm (2/10); e saco pericárdico com deposição de fibrina (2/10). No exame histopatológico foram evidenciados traqueíte (10/10), sinusite (5/5) e conjuntivite (3/4) hiperplásica linfoplasmocitária aguda; broncopneumonia fibrinonecrótica (5/10); pericardite fibrinosa aguda (2/10); e aerossaculite fibrinonecrótica (1/1). No exame de IHQ anti-MG foi evidenciada marcação na superfície extracelular dos cílios e/ou topo do epitélio da traqueia (10/10), brônquios (5/10) e seios nasais (4/5). Em sete dos dez casos analisados foi detectada a presença de MG por PCR em tempo real realizado a partir de amostras de suabe traqueal. A técnica de IHQ anti-MG utilizada como método de diagnóstico apresentou boa concordância com os sinais clínicos, as lesões histopatológicas e os resultados de PCR em tempo real.

Avian mycoplasmosis is caused by bacteria from the Mycoplasmataceae family. Mycoplasma gallisepticum (MG) is the most pathogenic and economically significant species affecting poultry. The aim of this study was to use the immunohistochemistry technique (IHC) as a diagnostic method for the MG infection in poultry. In this report we described two outbreaks of mycoplasmosis caused by MG in free-range chickens. Clinical signs were characterized by prostration, decreased appetite, difficult breathing, nasal and ocular discharge. Necropsy findings were serous secretion in conjunctiva (7/10) and seioses (4/10), edema and caseous exudate; air sacs thickened with foam and caseous exudate (6/10); trachea diffusely reddish (4/10); lungs with 0.5 cm whitish spots (2/10); and pericardial sac with fibrin exudate (2/10). Histologically was observed a lymphoplasmacytic hyperplastic acute tracheitis (10/10), seiositis (5/5) and conjunctivitis (3/4); fibrinonecrotic bronchopneumonia (5/10); acute fibrinous pericarditis (2/10); and fibrinonecrotic aerosaculitis (1/1). IHC anti-MG stained in the extracellular surface of ciliated brush border and/or in the top of epithelium of trachea (10/10), bronchi (5/10) and sinuses (4/5). In seven out of ten cases it was possible to detect MG by real-time PCR from tracheal swabs. IHC anti-MG used as a diagnostic method showed good correlation with clinical signs, lesions and real-time PCR results.