Differences in virulence and oocyst shedding profiles in lambs experimentally infected with different isolates of Cryptosporidium parvum

A wide spectrum of disease severity associated with cryptosporidiosis has been described, ranging from asymptomatic to fatal in both human and animal hosts. The reasons for the variations in severity are likely to be multifactorial, involving environmental, host and parasite factors. This paper describes two experimental infection trials in lambs, a symptomatic host for the parasite, to investigate variation in the clinical manifestations following infection with two distinct isolates of Cryptosporidium parvum. In the first experiment, groups of naïve lambs were challenged with one of two isolates (CP1 or CP2) at ​< ​1 week of age, to test the effect of the isolates on disease outcome. In a second experiment one group of lambs challenged at < 1 week of age (CP1) was then re-challenged with the same isolate at 6 weeks of age (CP1), while a second group was challenged for the first time at 6 weeks of age (CP1). This experiment examined age-related disease symptoms, oocyst shedding and the effect of prior exposure to the parasite on a subsequent homologous challenge. The two isolates were associated with significant differences in the demeanour of the animals and in the numbers of oocysts shed in the faeces. There were also differences in the duration and severity of diarrhoea, though these were not significant. The age of the lamb, at the time of a primary challenge (<1 week or 6 weeks), also resulted in differences in clinical outcomes, with younger lambs showing more severe clinical disease than the older lambs (feeding profiles and presentation of diarrhoea), while older lambs showed virtually no signs of infection but still produced large numbers of oocysts

Sero-occurrence of anti-Toxoplasma gondii antibodies and vertical transmission in slaughtered beef cows (Bos indicus) Soro ocorrência de anticorpos contra Toxoplasma gondii e transmissão vertical em vacas de corte (Bos indicus) abatidas

Abstract Toxoplasma gondii is a protozoan parasite recognized as an important public health problem. The objective of the present study was to evaluate the occurrence of anti-T. gondii antibodies in pregnant and non pregnant zebus' breed beef cows (Bos indicus), their fetuses, killed at an abattoir in northern of Paraná state. In the present study 169 cows were evaluated, 92 pregnant (in different stages of gestation) and 77 non pregnant. Sero-occurrence of anti-T. gondii antibodies was performed by Indirect uorescent antibody test (IFAT) considering positive animals with titers ≥ 50 for cows and ≥ 25 for fetuses. Blood (with EDTA) from pregnant cows and blood and tissue samples (brain, lung, heart, and liver) from their fetuses were collected and used for mouse bioassay. Antibodies against T. gondii were observed in 26.0% of cows and 2.5% of fetuses. There was no statistical difference when prevalence of toxoplasmosis was compared between pregnant (23.9%), and non-pregnant (28.6%) animals, and age of gestation (p > 0.59). However, the occurrence of anti-T.gondii antibodies increased with age of animals (p=0.004). Mouse bioassay showed three fetuses positives (3.2%), however, none T. gondii strain was isolated. The present study showed that transplacental transmission of T. gondii naturally occurs in zebu beef cows from Brazil, however, in low rate (5.4%). The anti-T. gondii antibodies occurrence increase with the age of animals, which could be related to the fact that main transmission in cattle T. gondii is horizontal. Key words: Toxoplasmosis, zebu, vertical transmission Resumo Toxoplasma gondii é um protozoário reconhecido como um dos mais importantes parasitas em saúde pública. O objetivo do presente estudo foi avaliar a ocorrência de anticorpos contra T. gondii em vacas de corte zebuínas (Bos indicus) gestantes, e seus fetos, bem como, em vacas não gestantes abatidas em um matadouro no norte do Paraná. No presente estudo foram avaliadas 169 vacas, 92 prenhas (em diferentes fases de gestação) e 77 não prenhas. A ocorrência de anticorpos contra T. gondii foi realizada por meio da reação de imuno uorescência indireta (IFI) considerando animais positivos aqueles com títulos ≥ 50 para as vacas e ≥ 25 para os fetos. Sangue (EDTA) de vacas prenhas e amostras de sangue e tecidos (cérebro, pulmão, coração, e fígado) de seus fetos foram coletadas e utilizadas para o bioensaio em camundongos. Anticorpos contra T. gondii foram observados em 26,0% das vacas e em 2,5% dos fetos Não houve diferença quando a soropositividade de anticorpos foi comparado entre vacas gestantes (23,9%), e não gestantes (28,6%), bem como, a idade da gestação (p > 0,59). No entanto, a ocorrência de anticorpos aumentou com a idade dos animais (p = 0,004). O bioensaio mostrou três fetos positivos (3,2%), porém, nenhuma cepa foi isolada. O presente estudo mostrou que a transmissão transplacentária de T. gondii ocorre naturalmente em vacas de corte zebuínas do Brasil, no entanto, esta ocorrência foi baixa (5,4%). A maior ocorrência de anticorpos associada com a idade dos animais poderia estar relacionada a transmissão horizontal do T. gondii nestes animais

Study of ecological niches from pathogenic yeasts of the species Cryptococcus neoformans and Cryptococcus gattii in Londrina City, PR

Os fungos patogênicos das espécies Cryptococcus neoformans e Cryptococcus gattii podem ser encontrados no meio ambiente em guano de pombos, solo com excrementos de pombos e pássaros, além de matéria vegetal de árvores. O objetivo deste estudo foi investigar a presença das espécies patogênicas de Cryptococcus em solo com excrementos de pombos, solo com matéria vegetal e em madeira em decomposição de partes ocas de árvores existentes em lugares públicos da cidade de Londrina, PR. Trinta locais foram selecionados dentre praças, parques e ruas da região central da cidade onde amostras foram coletadas de: solo com excretas de pombos (n=120), solo com matéria vegetal da base das árvores (n=120) e swab de matéria vegetal em decomposição de partes ocas de árvores, no período de junho de 2009 a março de 2010. As coletas abrangeram três estações do ano: inverno, primavera e verão, nesse período 360 amostras foram obtidas e analisadas em quatro diferentes etapas. As espécies foram identificadas por meio de análise microscópica da cultura e crescimento em meios seletivos. Um total de cinco amostras foi positivo para Cryptococcus spp. (1,38%), três amostras foram identificadas como C. neoformans (0,84%), duas amostras de solo com excrementos de pombos e uma amostra vegetal do solo. As amostras eram provenientes de um parque, uma rua e uma praça localizados na área central de Londrina. C. gattii foi isolado das outras duas amostras (0,54%), uma em solo com excrementos de pombos e outra em amostra de matéria vegetal do solo obtida de dois parques da cidade localizados em área desprotegida contra insolação e chuvas. Não foi obtido isolamento de Cryptococcus spp. das 120 amostras de swab de madeira em decomposição de partes ocas das 12 espécies de árvores amostradas. Os resultados das análises do meio ambiente confirmaram a ocorrência das espécies patogênicas Cryptococcus neoformans e Cryptococcus gattii em locais onde a população suscetível de humanos e animais podem ser expostos aos propágulos infecciosos dos fungos.The pathogenic fungi of the species Cryptococcus neoformans and Cryptococcus gattii could be found in the environment on pigeon guano, soil with pigeon and bird excreta and vegetable material from trees. The aim of this study was analyze the presence of the Cryptococcus pathogenic species on soil with pigeon excreta, soil with vegetable material and decayed wood of trunk hollows of trees from public places in the city of Londrina, PR. Thirty public places were selected from squares, parks and streets in the city centre where samples were collected from: soil with pigeon excreta (n=120), soil with vegetable material (n=120) and decayed wood of trunk hollows of trees (n=120), during June 2009 until March 2010. These collect comprised the seasons: winter, spring and summer, during this period 360 samples were obtained and analyzed in four different times. The species were identified by means of microscopic analysis from culture and their rising on selective medium. A total of five samples were positive to Cryptococcus spp. (1,38%) three were positive to Cryptococcus neoformans (0,84%) in two samples of soil with pigeon excreta, the other one on soil with vegetable material. The samples were originated from a park, a street and a square, placed in the city centre area of Londrina. Cryptococcus gattii was isolated from two samples (0,54%), one in soil with pigeon excreta and another in vegetable material obtained from the soil of two parks that were not protected against sunshine and rain. Cryptococcus spp. was not isolated in none of the 120 swabs samples of decayed wood trunk hollows from the 12 species of trees sampled. The results of the analyses from the environment confirmed the occurrence of the pathogenic species Cryptococcus neoformans e Cryptococcus gattii in places were the human and animal susceptible populations could be exposure to infectious fungi propagators

Differences in virulence and oocyst shedding profiles in lambs experimentally infected with different isolates of Cryptosporidium parvum

A wide spectrum of disease severity associated with cryptosporidiosis has been described, ranging from asymptomatic to fatal in both human and animal hosts. The reasons for the variations in severity are likely to be multifactorial, involving environmental, host and parasite factors. This paper describes two experimental infection trials in lambs, a symptomatic host for the parasite, to investigate variation in the clinical manifestations following infection with two distinct isolates of Cryptosporidium parvum. In the first experiment, groups of naïve lambs were challenged with one of two isolates (CP1 or CP2) at ​< ​1 week of age, to test the effect of the isolates on disease outcome. In a second experiment one group of lambs challenged at < 1 week of age (CP1) was then re-challenged with the same isolate at 6 weeks of age (CP1), while a second group was challenged for the first time at 6 weeks of age (CP1). This experiment examined age-related disease symptoms, oocyst shedding and the effect of prior exposure to the parasite on a subsequent homologous challenge. The two isolates were associated with significant differences in the demeanour of the animals and in the numbers of oocysts shed in the faeces. There were also differences in the duration and severity of diarrhoea, though these were not significant. The age of the lamb, at the time of a primary challenge (<1 week or 6 weeks), also resulted in differences in clinical outcomes, with younger lambs showing more severe clinical disease than the older lambs (feeding profiles and presentation of diarrhoea), while older lambs showed virtually no signs of infection but still produced large numbers of oocysts

Molecular characterization of Eurytrema coelomaticum in cattle from Paraná, Brazil

This study investigated the occurrence of Eurytremaspp. in cattle by analysis of the partial 18S rRNA gene sequence. Trematodes from 44 bovine pancreas were collected and classified based on typical morphological features. PCR assay and sequence analyses of amplified products confirmed that the trematodes classified as Eurytrema coelomaticum were phylogenetically distinct from those identified as E. pancreaticum. The results of this study represent the first molecular characterization of E. coelomaticum within the Americas, and provide an efficient method to differentiate digenean trematodes of domestic animals

Effect of a symbiotic on average weight gain and egg per gram of feces account of confined lambs

Este trabalho teve como objetivo avaliar o desempenho de cordeiros confinados por 45 dias, suplementados com simbiótico comercial. O experimento foi conduzido no Norte do Paraná.  Cordeiros Santa Inês, Suffolk e seus cruzamentos (n=44), alimentados com feno de aveia e concentrado (30:70), foram divididos em dois grupos: Controle (n=22), sem suplementação com simbiótico, e Simbiótico (n=22). Foram avaliados peso médio, ganho de peso médio diário (GMD) e contagem de ovos por grama de fezes (OPG) com intervalos de 15 dias. Não houve diferença em relação ao peso vivo médio (P > 0,05). O GMD do grupo Simbiótico durante o confinamento (280g/dia) foi superior ao Controle (238g/dia) (P 0.05). During the confinement, the ADWG in Symbiotic group (280g/day) was higher than in Control one (238g/day) (P < 0.05), achieving maximum value on the last 15 days of confinement (288g/ day). At the end of confinement, EPG decreased in Symbiotic group (864) (P < 0.05), as it increased in Control group (2864) (P < 0.05). Economic analysis showed economic return of R$ 782.31 for Simbiotic 1 Aluno (a) do Programa de Pós-graduação em Ciência Animal, Universidade Estadual de Londrina – UEL, Londrina-Pr

Detection and dissemination of Toxoplasma gondii in experimentally infected calves, a single test does not tell the whole story.

Although the detection of Toxoplasma gondii in bovine tissues is rare, beef might be an important source of human infection. The use of molecular techniques, such as magnetic capture qPCR (MC-qPCR), in combination with the gold standard method for isolating the parasite (mouse bioassay), may increase the sensitivity of T. gondii detection in infected cattle. The risk of transmission of the parasite to humans from undercooked/raw beef is not fully known and further knowledge about the predilection sites of T. gondii within cattle is needed. In the current study, six Holstein Friesian calves (Bos taurus) were experimentally infected with 106 T. gondii oocysts of the M4 strain and, following euthanasia (42 dpi), pooled tissues were tested for presence of the parasite by mouse bioassay and MC-qPCR

Soro ocorrência de anticorpos contra Toxoplasma gondii e transmissão vertical em vacas de corte (Bos indicus) abatidas

Toxoplasma gondii is a protozoan parasite recognized as an important public health problem. The objective of the present study was to evaluate the occurrence of anti-T. gondii antibodies in pregnant and non pregnant zebus’ breed beef cows (Bos indicus), their fetuses, killed at an abattoir in northern of Paraná state. In the present study 169 cows were evaluated, 92 pregnant (in different stages of gestation) and 77 non pregnant. Sero-occurrence of anti-T. gondii antibodies was performed by Indirect fluorescent antibody test (IFAT) considering positive animals with titers ? 50 for cows and ? 25 for fetuses. Blood (with EDTA) from pregnant cows and blood and tissue samples (brain, lung, heart, and liver) from their fetuses were collected and used for mouse bioassay. Antibodies against T. gondii were observed in 26.0% of cows and 2.5% of fetuses. There was no statistical difference when prevalence of toxoplasmosis was compared between pregnant (23.9%), and non-pregnant (28.6%) animals, and age of gestation (p > 0.59). However, the occurrence of anti-T.gondii antibodies increased with age of animals (p=0.004). Mouse bioassay showed three fetuses positives (3.2%), however, none T. gondii strain was isolated. The present study showed that transplacental transmission of T. gondii naturally occurs in zebu beef cows from Brazil, however, in low rate (5.4%). The anti-T. gondii antibodies occurrence increase with the age of animals, which could be related to the fact that main transmission in cattle T. gondii is horizontal.Toxoplasma gondii é um protozoário reconhecido como um dos mais importantes parasitas em saúde pública. O objetivo do presente estudo foi avaliar a ocorrência de anticorpos contra T. gondii em vacas de corte zebuínas (Bos indicus) gestantes, e seus fetos, bem como, em vacas não gestantes abatidas em um matadouro no norte do Paraná. No presente estudo foram avaliadas 169 vacas, 92 prenhas (em diferentes fases de gestação) e 77 não prenhas. A ocorrência de anticorpos contra T. gondii foi realizada por meio da reação de imunofluorescência indireta (IFI) considerando animais positivos aqueles com títulos ? 50 para as vacas e ? 25 para os fetos. Sangue (EDTA) de vacas prenhas e amostras de sangue e tecidos (cérebro, pulmão, coração, e fígado) de seus fetos foram coletadas e utilizadas para o bioensaio em camundongos. Anticorpos contra T. gondii foram observados em 26,0% das vacas e em 2,5% dos fetos Não houve diferença quando a soropositividade de anticorpos foi comparado entre vacas gestantes (23,9%), e não gestantes (28,6%), bem como, a idade da gestação (p > 0,59). No entanto, a ocorrência de anticorpos aumentou com a idade dos animais (p = 0,004). O bioensaio mostrou três fetos positivos (3,2%), porém, nenhuma cepa foi isolada. O presente estudo mostrou que a transmissão transplacentária de T. gondii ocorre naturalmente em vacas de corte zebuínas do Brasil, no entanto, esta ocorrência foi baixa (5,4%). A maior ocorrência de anticorpos associada com a idade dos animais poderia estar relacionada a transmissão horizontal do T. gondii nestes animais