Detecção de Circovírus suíno 2 (PCV2) por reação em cadeia pela Polimerase (PCR) nas fezes e baia de suínos em granja sem vacinação / Porcine circovirus 2 detection in feces and sty samples from an unvaccinated farm using PCR

The circovirosis caused by porcine circovirus 2 (PCV2) is responsible for generating economic losses in swine production in Brazil. Infected animals can develop post weaning multisystemic wasting syndrome (PMWS), reproductive disorders and respiratory diseases. An important subclinical manifestation leads to arrested development. Feces are the main form of contamination. Vaccination is the most effective way to decrease the viral circulation, because it minimizes viral shedding in feces. Unfortunately, the high cost prevents the use of the vaccine for many producers. The objective of this study was to detect PCV2 in stool samples collected from piglets and from the sty of a pig farm, unvaccinated for the agent. A total of 16 samples were collected using swabs, six from the rectum of animals and 10 from the sty. DNA extraction was performed using the Qiagen QIAamp kit, followed by PCR amplification. The amplicons were checked on agarose gel electrophoresis. Our results showed that 87.5% of the samples were positive for PCV2 (14/16), 83.3% of tested animals were infected (5/6) as well as 90% of the sty samples (9/10), indicating a high spread of the virus in the environment. These results were similar to those described in the literature for farms that also did not use vaccination to control PCV2 infection.

A circovirose causada pelo circovírus suíno 2 (PCV2) é responsável por gerar prejuízos econômicos na atividade suinícola no Brasil. Os animais infectados podem desenvolver a síndrome multissistêmica do definhamento, distúrbios reprodutivos e doenças do complexo respiratório. Há uma manifestação subclínica importante onde observa-se a queda no desempenho. A disseminação ocorre primariamente pelas vezes. A vacinação é a forma mais eficaz para a diminuição da circulação viral, pois minimiza a eliminação viral pelas fezes. Infelizmente, o alto custo inviabiliza a utilização da vacina por muitos produtores. O objetivo deste trabalho foi detectar o PCV2 em amostras de fezes coletadas de leitões e da baia de uma granja de suínos não vacinados para o agente. Foram coletadas 16 amostras usando suabes, sendo seis delas da ampola retal de animais e dez da baia. A extração do DNA foi feita com o kit QIAamp da Qiagen, seguida de amplificação por PCR. Os amplicons foram verificados em eletroforese em gel de agarose. 87,5% das amostras foram positivas para o PCV2 (14/16), sendo que 83,3% dos animais testados estavam infectados, (5/6) bem como 90% das amostras da baia (9/10), indicando uma alta disseminação do vírus no ambiente. Esses resultados foram semelhantes aos descritos em literatura para granjas que, também, não utilizavam a vacinação para o controle da infecção por PCV2.

Detecção de Circovírus suíno 2 (PCV2) por reação em cadeia pela Polimerase (PCR) nas fezes e baia de suínos em granja sem vacinação / Porcine circovirus 2 detection in feces and sty samples from an unvaccinated farm using PCR

The circovirosis caused by porcine circovirus 2 (PCV2) is responsible for generating economic losses in swine production in Brazil. Infected animals can develop post weaning multisystemic wasting syndrome (PMWS), reproductive disorders and respiratory diseases. An important subclinical manifestation leads to arrested development. Feces are the main form of contamination. Vaccination is the most effective way to decrease the viral circulation, because it minimizes viral shedding in feces. Unfortunately, the high cost prevents the use of the vaccine for many producers. The objective of this study was to detect PCV2 in stool samples collected from piglets and from the sty of a pig farm, unvaccinated for the agent. A total of 16 samples were collected using swabs, six from the rectum of animals and 10 from the sty. DNA extraction was performed using the Qiagen QIAamp kit, followed by PCR amplification. The amplicons were checked on agarose gel electrophoresis. Our results showed that 87.5% of the samples were positive for PCV2 (14/16), 83.3% of tested animals were infected (5/6) as well as 90% of the sty samples (9/10), indicating a high spread of the virus in the environment. These results were similar to those described in the literature for farms that also did not use vaccination to control PCV2 infection.(AU)

A circovirose causada pelo circovírus suíno 2 (PCV2) é responsável por gerar prejuízos econômicos na atividade suinícola no Brasil. Os animais infectados podem desenvolver a síndrome multissistêmica do definhamento, distúrbios reprodutivos e doenças do complexo respiratório. Há uma manifestação subclínica importante onde observa-se a queda no desempenho. A disseminação ocorre primariamente pelas vezes. A vacinação é a forma mais eficaz para a diminuição da circulação viral, pois minimiza a eliminação viral pelas fezes. Infelizmente, o alto custo inviabiliza a utilização da vacina por muitos produtores. O objetivo deste trabalho foi detectar o PCV2 em amostras de fezes coletadas de leitões e da baia de uma granja de suínos não vacinados para o agente. Foram coletadas 16 amostras usando suabes, sendo seis delas da ampola retal de animais e dez da baia. A extração do DNA foi feita com o kit QIAamp da Qiagen, seguida de amplificação por PCR. Os amplicons foram verificados em eletroforese em gel de agarose. 87,5% das amostras foram positivas para o PCV2 (14/16), sendo que 83,3% dos animais testados estavam infectados, (5/6) bem como 90% das amostras da baia (9/10), indicando uma alta disseminação do vírus no ambiente. Esses resultados foram semelhantes aos descritos em literatura para granjas que, também, não utilizavam a vacinação para o controle da infecção por PCV2.(AU)

Impacto do desmame no comportamento e bem-estar de leitões: revisão de literatura / Impact of weaning on behavior and welfare of piglets: A review

The swine production is characterized by high productivity due to improvements especially in environmental conditions, genetics and animal nutrition and is constantly evolving to meet the demands of the consumer market. In this context, a confl ict of interest occurs when combining high production rates in short time with the welfare animal. However some changes directly impact on production rates, as the weaning phase which is considered the most traumatic, with direct refl ection on the performance and welfare of animals. Weaning has a direct impact on the development of piglets and several factors corroborate that this phase is considered the most traumatic in the lives of animals. Early weaning can increase stress, raise the diarrhea index, reduce growth and increase mortality in swine. It is necessary to be more careful on weaning due to the inherent mellow process and all behavioral physiological, endocrine and productive issues involved.

A produção suína se caracteriza pela alta produtividade decorrente de melhorias principalmente em condições de ambiente, genética e nutrição animal, estando em constante evolução para atender as exigências do mercado consumidor. Neste contexto, um conflito de interesse acontece ao associar altos índices produtivos em curto espaço de tempo com o bem-estar dos animais. No entanto algumas mudanças impactam diretamente nos índices produtivos, como a fase de desmame que é considerada a mais traumática, com reflexo direto no desempenho e bem-estar dos animais. O desmame tem impacto direto no desenvolvimento dos leitões e vários fatores corroboram para que esta fase seja considerada a mais traumática na vida dos animais. O desmame precoce pode aumentar o estresse, elevar o índice de diarreia, reduzir o crescimento e aumentar a taxa de mortalidade na suinocultura. É preciso ser mais criterioso no desmame em virtude da delicadeza inerente ao processo e a todas as questões comportamentais, fisiológicas, endócrinas e produtivas envolvidas.

Impacto do desmame no comportamento e bem-estar de leitões: revisão de literatura / Impact of weaning on behavior and welfare of piglets: A review

The swine production is characterized by high productivity due to improvements especially in environmental conditions, genetics and animal nutrition and is constantly evolving to meet the demands of the consumer market. In this context, a confl ict of interest occurs when combining high production rates in short time with the welfare animal. However some changes directly impact on production rates, as the weaning phase which is considered the most traumatic, with direct refl ection on the performance and welfare of animals. Weaning has a direct impact on the development of piglets and several factors corroborate that this phase is considered the most traumatic in the lives of animals. Early weaning can increase stress, raise the diarrhea index, reduce growth and increase mortality in swine. It is necessary to be more careful on weaning due to the inherent mellow process and all behavioral physiological, endocrine and productive issues involved.(AU)

A produção suína se caracteriza pela alta produtividade decorrente de melhorias principalmente em condições de ambiente, genética e nutrição animal, estando em constante evolução para atender as exigências do mercado consumidor. Neste contexto, um conflito de interesse acontece ao associar altos índices produtivos em curto espaço de tempo com o bem-estar dos animais. No entanto algumas mudanças impactam diretamente nos índices produtivos, como a fase de desmame que é considerada a mais traumática, com reflexo direto no desempenho e bem-estar dos animais. O desmame tem impacto direto no desenvolvimento dos leitões e vários fatores corroboram para que esta fase seja considerada a mais traumática na vida dos animais. O desmame precoce pode aumentar o estresse, elevar o índice de diarreia, reduzir o crescimento e aumentar a taxa de mortalidade na suinocultura. É preciso ser mais criterioso no desmame em virtude da delicadeza inerente ao processo e a todas as questões comportamentais, fisiológicas, endócrinas e produtivas envolvidas.(AU)

Concomitant zearalenone ingestion and porcine circovirus-2 infection

Background: Researches have suggested that mycotoxins could corroborate the pathogenesis of porcine viral diseases. Zearalenone (ZEA), one of the most import mycotoxicosis in pigs result significant reproductive disorders. The circovirosis syndromes in pigs have been associated with multifactorial or predisposing conditions. No previous data have correlated ZEA with viral syndromes in Sus scrofa. In this report are described anamnesis, clinical and histological findings with zearalenone ingestion and PCV-2 infection in a Brazilian livestock. Case: Feeding ration was mixed and produced at the farm with low quality corn that was stored in barn with cement floor. During ten months, 28 farrowing occurred. Fifteen of them were normal and produced 145 animals, mean of 9.66 piglets per litter. Thirteen sows presented reproductive disorders, and one died. Eight of them had the delayed farrowing and three aborted. These animals produced 57 mummified fetuses (10-16cm crown-rump length), 23 aborted fetuses (60-72 days of gestation), four stillborn, two teratogenic fetuses and only 16 normal piglets. Skin pustules, hemorrhagic spots and petechiae, as well as coughing were observed in 88% of the animals and four piglets died. Diarrhea outbreaks frequently occurred in this period. Twenty five of 34 gilts (75%) showed longer estrous cycle, estrus returning, vulvae volume and mammary glands enlargement. Necropsies showed enlarged lymphatic nodes and kidneys. Histopathological and immunohistochemical analysis indicated the presence of Porcine Circovirus type 2 (PCV-2) in analyzed tissues. Toxicological tests demonstrated the presence of zearalenone (ZEA) in stomach contents with average of 8.75 µg/g and pesticides and aflatoxins were not detected. Discussion: The history, the clinical signs, the necropsy and histological findings suggested a mix of zearalenone mycotoxicosis and PVC-2 syndrome that was confirmed by PVC-2 tissue detection in immunohistochemical assay, and by food toxicological analysis. The ZEA average founded in stomach contents (8.75 µg/g could produce the reproductive disorders and could has exacerbated the circovirosis. The most frequent reproductive alteration observed in the farrowing was mummified fetuses that corresponded 66.7% of its products. The several reproductive disorders as abortion, stillborn, mummified fetuses, estrus returning, vulvae volume and mammary glands enlargement in gilts are frequently related to zearalenone mycotoxicosis. Appetite loss, apathy, wasting, cough and diarrhea and increased mortality and withdrawal rate in growth and post-weaning phases observed in this study are liked as the several descriptions in the Post-Weaning Multisystemic Wasting Syndrome. The hemorrhagic skin spots and increased kidneys, with multifocal glomerulonephritis, lymphohistiocytic interstitial nephritis to remember the several alterations in Porcine Dermatitis and Nephropathy Syndrome. Both syndromes by PCV-2 could be simultaneity occurring in this herd and could have a co-participation of the ZEA ingestion as aggravated factor. After contaminated corn to sorghum free of ZEA exchange at ration, the reproduction returned to normal level and no PCV-2 lesions were observed, suggesting the ZEA ingestion as one initial or aggravating factor for the PCV-2 syndromes. For the first time, this report describes historical, anamnesis, clinical and histological findings possibly associated with zearalenone contamination and PCV-2 infection in pigs.

GENOMAS DE VÍRUS DE DNA DE FITA SIMPLES DETECTADOS EM SOROS DE SUÍNOS COM SÍNDROME MULTISSISTÊMICA DO DEFINHAMENTO DO SUÍNO ATRAVÉS DE METAGENÔMICA

As doenças associadas ao circovírus suíno (DACS) causam impacto econômico negativo nos sistemas de criação de suínos no mundo todo. As perdas incluem tratamento da doença, mortalidade, bem como diminuição no desempenho dos animais. Uma das manifestações mais relevantes das DACS é a síndrome multissistêmica do definhamento dos suínos (SMDS). O principal agente patogênico na causa da SMDS é o circovírus suíno tipo 2 (PCV2), no entanto, estudos observacionais e experimentais demonstraram que outros agentes estão envolvidos na patogênese e manifestação dos sinais clínicos. O sequenciamento de alto desempenho aliado a metagenômica são ferramentas que tornam possível a identificação da microbiota total de uma determinada amostra, independentemente de cultivo dos microrganismos. Visando contribuir para o conhecimento dos possíveis vírus envolvidos na SMDS, o presente trabalho realizou o sequenciamento genético de alto desempenho de soros de suínos e posterior análise do metagenoma resultante. Foram utilizadas amostras de soro coletadas em 2008, de 16 suínos com sinais clínicos da SMDS, entre 80 e 100 dias de idade, em uma granja no interior do Rio Grande do Sul. Os dados revelaram sequências virais de PCV2, parvovírus suíno tipo 1 a 6 (PPV1-6), torque teno vírus de suínos (TTSuV) tipo 1b, k2a e k2b e vírus de DNA circular de fita simples codificador de proteína associada a replicação (CRESS). A ocorrência de PCV2, PPV1-5 e TTSuV já foi descrita em suínos com SMDS, portanto este estudo reforça resultados anteriores. O PPV6 foi recentemente descrito na China, Europa e Estados Unidos, e os estudos não relacionaram o vírus com nenhuma doença específica de suínos. Os CRESS já foram identificados em todos os continentes, em vários tipos de amostras, incluindo fezes de suínos, mas sem nenhuma conexão com doenças de animais. Portanto, este é o primeiro relato de PPV6 e CRESS em suínos apresentando sinais de SMDS. Porém estudos posteriores são necessários para poder atribuir relação entre PPV6 e CRESS no desenvolvimento da SMDS.

Porcine circovirus associated disease (PCVAD) is one of the causes of negative economic impact on pig farming systems described worldwide. Losses include expenditures with treatment, increased mortality rates, and decreased productivity. One of the most relevant manifestations of PCVAD is the post-weaning multisystemic wasting syndrome (PMWS). The main pathogen present in PMWS is porcine circovirus type 2 (PCV2). However, observational and experimental studies have shown that other agents may be involved in the pathogenesis and clinical manifestation. High-throughput sequencing combined with metagenomics analyses make it possible to identify the total microbiota in a given sample, regardless of microorganism culture. In order to contribute to the knowledge of the viruses involved in PMWS, the present study carried out the high-throughput sequencing of swine sera and subsequent analysis of the resulting metagenome. Sixteen serum samples collected in 2008 on a farm in Rio Grande do Sul, from 80 and 100 days old pigs with clinical signs of PMWS, were examined. Data revealed viral sequences of PCV2, porcine parvovirus type 1 through 6 (PPV1-6), torque teno sus virus (TTSuV) types 1b, k2a and k2b and circular replication-associated protein (Rep) encoding single-stranded (CRESS) DNA viruses. The occurrences of PCV2, PPV1-5 and TTSuV have already been described in pigs with PMWS, so this study reinforces previous results. PPV6 was recently described in China, Europe and the United States, and the studies did not correlate the virus to any specific disease. CRESS DNA viruses have been identified on all continents in various types of samples, including swine feces, but without any connection to animal diseases. The present study is the first report of PPV6 and CRESS in pigs presenting PMWS signals. However, further studies are necessary to be able to attribute the relationship between PPV6 and CRESS in the development of SMDS.

Supply of porcine spray-dried plasma diluted in acidic water to pigs affected by post-weaning multisystemic wasting syndrome (pmws) at the beginning of finishing / Fornecimento de plasma suíno spray-dried diluído em água acidificada para leitões com sintomas de circovirose no início da fase de crescimento e terminação

The effect of the spray-dried porcine plasma diluted in drinking acidified water for recovery of piglets with clinical signs of the Post-Weaning Multisystemic Wasting Syndrome (PMWS) was studied. The experiment was conducted in eight finishing units of an agroindustry of Santa Catarina State, Brazil, with positive diagnosis of PMWS by histopathology, immunohistochemistry (IHC) and polimerase chain reaction (PCR). The study was initiated around 14 days after the lodging of the piglets and concluded 42 days later. The experiment was randomly designed by weight and sex with two treatments: T1 - water ad libitum as a control group and T2 a solution constituted of porcine plasma (250g) in drinking acidified water (10L). The animals were distributed into two batch pens in the same facility with nine or ten piglets per pen, being one the control pen and the other one the treated pen. The following variables were evaluated: pH of water and solution; individual weight and clinical conditions of the piglets; solution intake within the period from 0 to 14 days, feed intake and feed conversion rate; mortality rate, histopathology and IHC analysis of the animals that died. The piglets of T2 presented clinical improvement during the 14 days of the experiment and a better feed conversion rate at 28 days of the experiment. Performance data did not show statistical difference between the trea

Estudou-se o efeito do plasma suíno spray-dried ultrafiltrado (AP920â) diluído em água de bebida acidificada com ácido Selkoâ-pH, para recuperação de leitões com sinais clínicos da Síndrome Multissistêmica do Definhamento (SMD). O experimento foi conduzido em oito unidades de terminação de uma agroindústria de Santa Catarina com confirmação da SMD pela histopatologia, imunoistoquímica (IHQ) e reação em cadeia da polimerase. As granjas manejavam as instalações no sistema de todos dentro todos fora com vazio sanitário de sete dias entre lotes. O estudo foi iniciado aos 14 dias após o alojamento dos leitões e finalizado 42 dias depois. O experimento foi delineado aleatoriamente por peso e sexo com dois tratamentos: T1 (controle) com água à vontade e T2 (tratado) com solução composta por 250g de plasma suíno em 10L de água de bebida acidificada com 12mL de ácido. Os animais foram distribuídos em duas baias na mesma instalação com nove ou dez leitões por baia, sendo uma controle e a outra tratado. As variáveis avaliadas foram: pH da água e da solução; peso individual e condição clínica dos leitões; consumo das soluções no período de 0 a 14 dias, consumo de ração e conversão alimentar; taxa de mortalidade, exame histopatológico e imunoistoquímico dos animais que morreram. Os leitões do T2 apresentaram melhora clínica nos 14 dias e melhor conversão alimentar nas avaliações aos 28 dias

Pesquisa de antígenos e anticorpos contra Circovírus Suíno II em suínos com e sem sintomatologia da síndrome multisistêmica do definhamento em granjas comerciais mineiras / Research of antigen and antibodies against Porcine Circovirus Type - 2 in pigs with and without postweaning multsystemic wasting syndrome from commercial farms of Minas Gerais state

Circovirus Suíno Tipo-2 (CSV-2) é um vírus não-envelopado, DNA fita única circular, classificado na família de Circoviridae, relacionado à Síndrome Multisistêmica do Definhamento de Suínos (SMDS) de leitões. A técnica de Imuno-Histoquímica (IHQ) é aplicada na detecção de antígenos do (CSV-2) em tecido lesionados. Entretanto, suínos infectados com CSV-2 assintomáticos ou com infecções subclínicas podem disseminar o vírus no plantel. A pesquisa de anticorpos contra o CVS-2 em porcos aparentemente saudáveis pode sugerir o risco de ingresso de vírus. Neste trabalho foram investigados antígenos e anticorpos contra CVS-2 de porcos de granjas comerciais de sete e oito mesorregiões de Estado de Gerais de Minas (MG). 32 porcos com idades de cinco a onze semanas que apresentaram sinais clínicos de SMDS foram necropsiados. Antígenos do CVS-2 foram investigados nos porcos sacrificados (grupo I) e amostras de demanda de diagnóstico (grupo II) pela IHQ. 7.60% e mais de 60%do primeiro e segundo grupo, respectivamente, foram positivos para antígeno viral. Em todos, marcação intensa de macrófagos e histiócitos, especialmente nos linfonodos e pulmão, evidenciou antígenos a CVS-2. Em paralelo, 955 amostras de soros de porcos de 35 granjas comerciais de ciclo completo sem sintomatologia clínica de SMDS foram investigadas para a detecção de anticorpos contra o CVS-2 aplicando a técnica de Imunoperoxidase em Monocamada de Células (IPMC). Todos os rebanhos de suínos (100%) apresentaram animais positivos (nível de confiança 90% a 100%) com freqüência de 96,6% de porcos reagentes (nível de confiança 94.7% a 98,6%). Os títulos de anticorpos contra o CVS-2 variou 1:320 (médio) a 1:10.240 (alto). Os resultados sugerem que pelo menos 2,66% e 9% dos porcos das regiões Triângulo Mineiro e Zona da Mata, respectivamente, nesta amostragem poderiam desenvolver SMDS clínica e esta porcentagem alcança 3,35% no total dos soros.

Porcine Circovirus Type 2 (PCV-2) is a non-enveloped circular single stranded DNA virus classified in the Circoviridae family related to post weaning multi systemic wasting syndrome (PMWS) in piglets.Immune-Histochemical (IHC) techniques are applied to detected PCV-2 antigen in the animal tissue injuries. Although, asymptomatic or sub clinic PCV-2 infected pigs could disseminate the virus in the flock. Serologic survey on apparently health pigs could suggest the virus ingression risk. In this work, antigens and antibodies against PCVS-2 in swine from commercial farms of seven and eight mesorregions of Minas Gerais State (MG) were investigated. 32 pigs with ages from five to eleven weeks which presented SMDS clinical signs were submitted to necropsy. PCV-2 antigens were investigated either from sacrificed pigs (Group I) and diagnosis demand samples (Group II) by IHC. 7,60% and more than 60% of the first and second groups, respectively, were positive for viral antigen. In both of them, intense marking of macrophages and histiocytes, especially in the lymph nodes and lung, evidenced antigens to CVS-2. In parallel, Immunoperoxidase Monolayer Assay (IPMA) was applied to antibody against PCV-2 screened in 955 pigs from 35 complete cycle commercial farms from same mesorregions. All pig flocks (100%) presented positive animals (confidence level 90% to 100%) and the frequency of reacting pigs varied 96.6% (confidence level 94,7% to 98,6%). PCV-2 antibody titers ranged 1:320 (medium) to 1:10.240 (high). The results suggest that 2.66% and 9% of pigs from Triângulo Mineiro and Zona da Mata regions respectively, would be able to develop clinical SMDS and that percentage reach 3.35% in the total serum.

Perfil sorológico, viremia e eliminação do circovírus suíno tipo 2 em animais naturalmente infectados pertencentes a granjas com ou sem a síndrome da refugagem multissistêmica / Serological profile, viremia and PCV2 shedding in naturally infected pigs of herds with or without postweaning multisystemic wasting syndrome

Um estudo virológico e sorológico seccional (E1) e outro longitudinal (E2) foram realizados em granjas com (G2 e G3) e sem (G1) a síndrome de refugagem multissitêmica (SRM) no Brasil. Foram coletadas amostras de sangue, soro, swabs nasal e retal de animais de cada categoria do ciclo produtivo: porcas, leitões maternidade, creche, recria e terminação. Em E1, nas granjas G1a e G2, foram amostrados 40 animais de cada categoria. Em E2, nas granjas G1b e G3, 35 leitões na maternidade foram identificados e amostrados ao longo do ciclo produtivo. O soro foi avaliado para presença de anticorpos contra circovírus suíno tipo 2 (CVS2) e sangue e swabs para presença do ácido nucléico viral. Em E1, a categoria porcas possuía altas taxas de animais virêmicos e soropositivos, com porcentagem de porcas com títulos altos superior a G2. Em G1a a queda de imunidade passiva ocorreu entre o final da fase de creche e início da recria com aumento da eliminação viral em swabs e subsequente soroconversão. Em G2 a queda ocorreu entre a fase final da maternidade e início da creche, com diminuição da eliminação viral. Em E2, a queda da imunidade materna ocorreu entre a 1ª e 2ª coleta em G1b; e em G3, entre a 2ª e 3ª coleta. Em ambas as granjas, a queda de imunidade passiva coincidiu com o aumento da viremia e eliminação viral e a soroconversão ocorreu entre a 3ª e 4a coleta em ambas as granjas com aumento da média de título de anticorpos e declínio da viremia. Viremia e eliminação viral foram detectadas em todas as coletas realizadas; 42% dos animais amostrados em E2 foram virêmicos em todas as coletas e todas as amostras de tecido coletadas no abate foram positivas para o CVS2. Este estudo confirma a persistência da viremia mesmo em presença de altos títulos de anticorpos e que o perfil sorológico em um rebanho com e sem a presença da síndrome pode ser diferente, principalmente em relação à duração da imunidade passiva.(AU)

A virological and serological cross-sectional study (E1) and a longitudinal study (E2) were performed on herds with (G2 and G3) and without (G1) post weaning multisystemic syndrome (PMWS) in Brazil. Blood, serum, nasal and rectal swabs samples were collected of sows, farrowing piglets, nursery, growing and finishing pigs. In E1, were sampled 40 animals in each category (G1a and G2). In E2, (G1b and G3), 35 farrowing piglets were identified and sampled along the production cycle. Porcine circovirus type 2 (PCV2) antibodies were assayed. A PCR was used to detected PCV2 genome in blood and swabs. In E1, sows had high rates of viremic and seropositives animals, with percentage of sows with high antibodies titers greater than G2. Passive antibodies decline occurred between nursery and growing area with increased viral shedding in swabs and subsequent seroconversion in G1. In G2, the passive antibodies decay occurred in nursery, with a reduction in viral shedding. In E2, the decline of maternal immunity occurred between the 1st and 2nd collection in G1b, and between 2nd and 3rd collections in G3. In both herds, the decay of passive immunity coincided with increased viremia and viral shedding; and seroconversion occurred between the 3rd and 4th collection in both herds with decline of viremia. Viremia and viral shedding was detected in all samples days, 42% of animals sampled in E2 were viremic and all tissue samples collected at slaughterwere positive for PCV2. This study confirms the persistence of viremia even in the presence of high titers of antibodies and the serological profile in a herd with or without PMWS may be different, especially with regard to the passive immunity duration.(AU)

Frequência de suínos soropositivos para Salmonella sp. em granjas afetadas em diferentes níveis de severidade pela Síndrome Multissistêmica de Definhamento do Leitão Desmamado / Frequency of Salmonella seropositive pigs in farms affected by different severity levels of the Post-weaning Multisystemic Wasting Syndrome

The Post-weaning Multisystemic Wasting Syndrome (PMWS) has caused considerable losses due to mortality and wasting of pigs and has been often associated with co-infections with other viral or bacterial agents. At the present time, PMWS is the most important infectious disease syndrome in the Brazilian swine production. With a variety of symptoms, this syndrome affects the immune system and can thus open the door for co-infections, which results in performance losses. Positive results of immunohistochemistry for PCV2 in pigs, we obtained the isolation of Salmonella enterica in 36.2% cases, demonstrate that co-infection occurs in Brazilian herds. However, there is still determining whether there is an increase in the number of carriers of Salmonella sp. in swine herds affected by PCV2. From this, the present study aimed to investigate the frequency of animals positive for Salmonella sp. in pig herds with different levels of intensity of involvement by PMWS.

Frequência de suínos soropositivos para Salmonella sp. em granjas afetadas em diferentes níveis de severidade pela Síndrome Multissistêmica de Definhamento do Leitão Desmamado / Frequency of Salmonella seropositive pigs in farms affected by different severity levels of the Post-weaning Multisystemic Wasting Syndrome

The Post-weaning Multisystemic Wasting Syndrome (PMWS) has caused considerable losses due to mortality and wasting of pigs and has been often associated with co-infections with other viral or bacterial agents. At the present time, PMWS is the most important infectious disease syndrome in the Brazilian swine production. With a variety of symptoms, this syndrome affects the immune system and can thus open the door for co-infections, which results in performance losses. Positive results of immunohistochemistry for PCV2 in pigs, we obtained the isolation of Salmonella enterica in 36.2% cases, demonstrate that co-infection occurs in Brazilian herds. However, there is still determining whether there is an increase in the number of carriers of Salmonella sp. in swine herds affected by PCV2. From this, the present study aimed to investigate the frequency of animals positive for Salmonella sp. in pig herds with different levels of intensity of involvement by PMWS.(AU)

Perfil sorológico para circovírus suíno tipo 2 em granjas comerciais de suínos no Brasil / Serological profiles to porcine circovirus type 2 antibodies in Brazil

A técnica de imunoperoxidase em monocamada de células (IPMC) para demonstração de anticorpos contra o circovírus suíno tipo 2 (CVS2) foi empregada para a investigação sorológica em oito granjas de suínos destinadas à produção comercial. Das 240 amostras de soros testadas, 229 (95,4%) foram reagentes com títulos que variaram de 20 até 10.240. Títulos de anticorpos foram detectados nas faixas etárias de duas a três semanas até animais acima de 24 semanas e encontrados em granjas com e sem a síndrome multissistêmica do definhamento (SMD). A média dos títulos de anticorpos revelou diferenças estatísticas (P<0,05) nas faixas etárias de 11 a 13 e 14 a 22 semanas nos animais oriundos de granjas com e sem a SMD. Os resultados refletem a importância de conhecer o perfil sorológico do rebanho e assegurar a implantação de um efetivo cronograma de vacinação contra o CVS2.(AU)

The immunoperoxidase in monolayer cells (IPMC) technique for the demonstration of antibodies against type 2 porcine circovirus (PCV2) was used for the serological investigation in eight industrial swine farms. Out of the 240 tested sera, 229 (95,4%) were reactive with titers which varied from 20 up to 10.240. Titers of antibodies were detected in pigs from two to three weeks of age up to above 24 weeks of age, and were observed in farms with and without clinical signs indicative of the post-weaning multisystemic wasting syndrome (PMWS). Analysing the mean titers, statistical differences (P<0.05) were evidentiated in two age intervals, of 11 to 13 and 14 to 22 weeks of age. The results indicate the importance of determining the serological profiles of commercial swine herds, in order to enable the implantation of effective hygiene and vaccination protocols for PCV2 prevention.(AU)

Transmission of porcine circovirus 2 (PCV2) by semen and viral distribution in different piglet tissues

Porcine circovirus infections are caused by the porcine circovirus 2 (PCV2). Among six different clinical manifestations involving respiratory, enteric, nervous and reproductive signs, the postweaning multisystemic wasting syndrome (PMWS) is the most important and studied disease. However, reproductive failures associated with PCV2 have been increasingly reported. Some studies have shown the possible contamination of sows by semen of PCV2 positive boars. In order to investigate the transmission of PCV2 by contaminated semen and its ability to infect the sow and piglets, 20 PCV2 negative sows were inseminated, 10 with negative boar semen and 10 with previously nested-PCR tested positive boar semen. The sows were weekly monitored and blood samples were collected. Based on the results, 4 out 20 sows were selected (1 sow was PCR negative and inseminated with a negative semen, 2 sows were PCR negative and inseminated with a positive semen and 1 sow was PCR negative and inseminated with a positive semen, but became PCR positive around the 30 days of pregnancy). After weaning, 12 male piglets, 3 of each sow, were selected and maintained under isolation. In order to investigate which organs harbored the virus, the young pigs were necropsied around 9 months of age. Samples of serum collected monthly were tested by immunocitochemistry (ICC), and all 12 pigs serum converted. Samples of lymphoid, systemic and reproductive organs were analyzed by nested-PCR and immunohistochemistry (IHC). Evaluation of the samples by nested-PCR, revealed that several tissues were positive in 10 of 12 pigs, mainly the lymph nodes, bone marrow and spleen. Various samples were positive by IHC in 8 of 12 piglets, being the lymph nodes, tonsils and bulbourethral glands the most frequently positive. Thus, the results of testing different samples, in the 3 tests (ICC, nested-PCR and IHC) were complementary. These results show that PCV2 transmission through semen to the sows...(AU)

Identificação do circovírus suíno tipo 2 por reação em cadeia da polimerase e por imunoistoquímica em tecidos suínos arquivados desde 1988 no Brasil

Postweaning multisystemic wasting syndrome (PMWS) is of economical importance a disease caused by porcine circovirus type 2 (PCV2). A retrospective investigation was performed on paraffin-embedded organs samples from swine submitted to Embrapa Swine and Poultry Research Center between 1985 and 1998 for histopathologic diagnosis. A total of 25 cases were chosen from the archival collection of the Animal Health Laboratory at Embrapa Swine and Poultry based on characteristic pathological lesions of PMWS, such as lymphadenopathy, interstitial pneumonia, hepatitis and interstitial nephritis. The sections were investigated by nested-PCR (polymerase chain reaction) which used specific primers for the ORF2 sequence of the PCV2 and by immunohistochemistry using a monoclonal antibody specific for PCV2 capsid antigen. Virus specific DNA and antigen were detected in tissue samples of two out of 25 analyzed cases. The earliest positive sample originated from 1988. These results indicate that PCV2 is present in Brazil since 1988.

A síndrome multissistêmica do definhamento dos suínos (SMDS) é uma doença de importância econômica causada pelo circovírus suíno tipo 2 (PCV2). Uma pesquisa retrospectiva foi realizada em amostras de órgãos de suínos fixados em blocos de parafina arquivados, que haviam sido submetidos à Embrapa Suínos e Aves entre 1985 e 1998 para o diagnóstico histopatológico. Vinte e cinco casos foram selecionados com base nas lesões histológicas características da SMDS, tais como linfoadenopatia, pneumonia intersticial, hepatite e nefrite intersticial. A presença de PCV2 nos cortes histológicos foi pesquisada por reação em cadeia da polimerase interna (nested-PCR), na qual utilizou-se primers específicos para a seqüência da ORF2 do PCV2 e também por imunoistoquímica, utilizando um anticorpo monoclonal específico para o capsídeo do PCV2. O DNA viral e os antígenos específicos do PCV2 foram detectados em amostras de tecidos de dois dos 25 casos analisados, sendo um desses datado de 1988. Esses resultados indicam que o PCV2 já estava presente no Brasil desde 1988.

Identificação do circovírus suíno tipo 2 por reação em cadeia da polimerase e por imunoistoquímica em tecidos suínos arquivados desde 1988 no Brasil

Postweaning multisystemic wasting syndrome (PMWS) is of economical importance a disease caused by porcine circovirus type 2 (PCV2). A retrospective investigation was performed on paraffin-embedded organs samples from swine submitted to Embrapa Swine and Poultry Research Center between 1985 and 1998 for histopathologic diagnosis. A total of 25 cases were chosen from the archival collection of the Animal Health Laboratory at Embrapa Swine and Poultry based on characteristic pathological lesions of PMWS, such as lymphadenopathy, interstitial pneumonia, hepatitis and interstitial nephritis. The sections were investigated by nested-PCR (polymerase chain reaction) which used specific primers for the ORF2 sequence of the PCV2 and by immunohistochemistry using a monoclonal antibody specific for PCV2 capsid antigen. Virus specific DNA and antigen were detected in tissue samples of two out of 25 analyzed cases. The earliest positive sample originated from 1988. These results indicate that PCV2 is present in Brazil since 1988.

A síndrome multissistêmica do definhamento dos suínos (SMDS) é uma doença de importância econômica causada pelo circovírus suíno tipo 2 (PCV2). Uma pesquisa retrospectiva foi realizada em amostras de órgãos de suínos fixados em blocos de parafina arquivados, que haviam sido submetidos à Embrapa Suínos e Aves entre 1985 e 1998 para o diagnóstico histopatológico. Vinte e cinco casos foram selecionados com base nas lesões histológicas características da SMDS, tais como linfoadenopatia, pneumonia intersticial, hepatite e nefrite intersticial. A presença de PCV2 nos cortes histológicos foi pesquisada por reação em cadeia da polimerase interna (nested-PCR), na qual utilizou-se primers específicos para a seqüência da ORF2 do PCV2 e também por imunoistoquímica, utilizando um anticorpo monoclonal específico para o capsídeo do PCV2. O DNA viral e os antígenos específicos do PCV2 foram detectados em amostras de tecidos de dois dos 25 casos analisados, sendo um desses datado de 1988. Esses resultados indicam que o PCV2 já estava presente no Brasil desde 1988.

Coinfecção experimental de circovírus suíno tipo 2 isolado no Brasil e parvovírus suíno em suínos SPF / Experimental coinfection of SPF pigs with porcine circovirus type 2 isolated in Brazil and porcine parvovirus

Avaliou-se a patogenicidade do circovírus suíno tipo 2 (PCV2) isolado no estado de Santa Catarina mediante coinfecção experimental com parvovírus suíno (PPV). Foram utilizados 24 leitões specific pathogen free (SPF) com cinco dias de idade, distribuídos em quatro grupos (G), alojados em salas independentes e inoculados por via intranasal: G1 - controle (n=4); G2 - inoculados com PCV2 (n=7); G3 - inoculados com PPV (n=6); G4 - inoculados com PCV2 e PPV (n=7). Os animais foram monitorados diariamente para avaliação clínica e necropsiados 48 dias após a infecção. As principais lesões anatomopatológicas observadas nos suínos do G2 e G4 foram: aumento do volume dos linfonodos, depleção linfocitária com redução dos folículos linfóides nos órgãos linfocitários e presença de infiltrado eosinofílico nos linfonodos. A técnica de nested-PCR para PCV2 foi utilizada detectando DNA viral em órgãos de todos os animais do G2 e G4. O PCV2 infectou suínos SPF por via intranasal e foi detectado em outros órgãos, com mais lesões histopatológicas e em maior proporção nos animais coinfectados com PPV (G4), quando comparados aos infectados somente com PCV2 (G2).(AU)

The virulence of porcine circovirus type 2 (PCV2) isolated in Santa Catarina State by coinfection with porcine parvovirus (PPV) was investigated. Twenty-four, 5-day-old SPF pigs were distributed into four groups, housed in separate rooms and inoculated by intranasal route: G1 - control (n=4); G2 - inoculated with PCV2 (n=7); G3 - inoculated with PPV (n=6); G4 - inoculated with PCV2 and PPV (n=7). The animals were monitored daily for clinical evaluation and were necropsied 48 days after the infection. The pathological lesions seen in G2 and G4 pigs were: enlargement of lymph nodes, mild to moderate lymphoid cell depletion, affecting lymphoid follicles in lymphoid organs and presence of infiltration by eosinophils in lymph nodes. PCV2 DNA was detected by a nested-PCR in all pigs of G2 and G4. These findings confirmed that pigs were successfully infected intranasally with PCV2. The presence of PCV2 DNA in tissue samples and the pathological lesions were more evident in pigs infected with both PCV2 and PPV than in pigs infected with PCV2 alone.(AU)

Frequência de suínos soropositivos para Salmonella sp. em granjas afetadas em diferentes níveis de severidade pela Síndrome Multissistêmica de Definhamento do Leitão Desmamado

Background:   The Post-weaning Multisystemic Wasting Syndrome (PMWS) has caused considerable losses due to mortality and wasting of pigs and has been often associated with co-infections with other viral or bacterial agents. At the present time, PMWS is the most important infectious disease syndrome in the Brazilian swine production. With a variety of symptoms, this syndrome affects the immune system and can thus open the door for co-infections, which results in performance losses. Positive results of immunohistochemistry for PCV2 in pigs, we obtained the isolation of Salmonella enterica in 36.2% cases, demonstrate that co-infection occurs in Brazilian herds. However, there is still determining whether there is an increase in the number of carriers of Salmonella sp. in swine herds affected by PCV2. From this, the present study aimed to investigate the frequency of animals positive for Salmonella sp. in pig herds with different levels of intensity of involvement by PMWS. Material, Methods and Results: Productive performance data and most prevalent symptoms were investigated in herds associated to 11 Brazilian swine companies that reported the occurrence of PMWS. The production systems, where the presence of S. enterica in pigs had been previously confirmed, was selected. A three-site management system was adopted, with each stage (breeding, nursery and finishing) housed in separa

Frequência de suínos soropositivos para Salmonella sp. em granjas afetadas em diferentes níveis de severidade pela Síndrome Multissistêmica de Definhamento do Leitão Desmamado

Background:   The Post-weaning Multisystemic Wasting Syndrome (PMWS) has caused considerable losses due to mortality and wasting of pigs and has been often associated with co-infections with other viral or bacterial agents. At the present time, PMWS is the most important infectious disease syndrome in the Brazilian swine production. With a variety of symptoms, this syndrome affects the immune system and can thus open the door for co-infections, which results in performance losses. Positive results of immunohistochemistry for PCV2 in pigs, we obtained the isolation of Salmonella enterica in 36.2% cases, demonstrate that co-infection occurs in Brazilian herds. However, there is still determining whether there is an increase in the number of carriers of Salmonella sp. in swine herds affected by PCV2. From this, the present study aimed to investigate the frequency of animals positive for Salmonella sp. in pig herds with different levels of intensity of involvement by PMWS. Material, Methods and Results: Productive performance data and most prevalent symptoms were investigated in herds associated to 11 Brazilian swine companies that reported the occurrence of PMWS. The production systems, where the presence of S. enterica in pigs had been previously confirmed, was selected. A three-site management system was adopted, with each stage (breeding, nursery and finishing) housed in separa

Diagnosis of post-weaning multisystemic wasting syndrome in pigs in Brazil caused by porcine circovirus type 2 / Diagnóstico da síndrome da refugagem multissistêmica em suínos no Brasil causada pelo circovírus suíno tipo 2

This report describes the first preliminary characterization of porcine circovirus type 2 (PCV2) isolates from pigs affected with post-weaning multisystemic wasting syndrome (PMWS) in Brazil. Diseased pigs were examined at necropsy and by histopathology. Macroscopic and microscopic analyses revealed lesions reported to be typical of PMWS, which included, respectively, emaciation, enlargement of lymph nodes, thymus atrophy and interstitial pneumonia, and granulomatous lymphadenitis with syncytial cells, among others. Using nested polymerase chain reaction (PCR) or imunoperoxidase it was possible to detected DNA or antigen of PCV2, respectively. The PCR' s amplified fragment could be differentiated from PCV1 and PCV2 from one another by restriction fragment length polymorphism (RFLP) analysis. PCV2 DNA was detected in 70% (14/20) of samples of pigs with clinical signs and lesions associated with PMWS. This study shows that PCV2 is associated with lesions and symptoms indicative of PMWS in pigs. It is also shown that the Brazilian PCV2 isolates may have variation in their genome.(AU)

Este trabalho descreve a primeira caracterização preliminar de isolados de circovírus suíno tipo 2 (PCV2) a partir de órgãos de suínos acometidos pela síndrome da refugagem multissistêmica (SRM) no Brasil. Leitões doentes foram examinados à necropsia e por histopatologia. Análises macroscópicas e microscópicas demonstraram lesões típicas de SRM, respectivamente, emagrecimento, aumento do volume dos linfonodos, atrofia de timo e pneumonia intersticial, e linfadenite granulomatosa com células sinciciais, entre outras. A presença de antígeno ou DNA do PCV2 foi demonstrada por imunoperoxidase ou reação da polimerase em cadeia "nested" (nested PCR), respectivamente. Foi possível diferenciar PCV1 e PCV2 por análises de polimorfismo de fragmento de restrição (RFLP) do fragmento amplificado da PCR. O DNA do PCV2 foi detectado em 70% (14/20) das amostras obtidas de suíno com sintomatologia clínica e lesões associadas com SRM. Este estudo apresenta a associação de PCV2 com lesões e sinais clínicos de SRM em suínos e também indica que os isolados do PCV2 brasileiros podem apresentar variações genômicas.(AU)

SUPPLY OF PORCINE SPRAY-DRIED PLASMA DILUTED IN ACIDIC WATER TO PIGS AFFECTED BY POST-WEANING MULTISYSTEMIC WASTING SYNDROME (PMWS) AT THE BEGINNING OF FINISHING / FORNECIMENTO DE PLASMA SUÍNO SPRAY-DRIED DILUÍDO EM ÁGUA ACIDIFICADA PARA LEITÕES COM SINTOMAS DE CIRCOVIROSE NO INÍCIO DA FASE DE CRESCIMENTO E TERMINAÇÃO

The effect of the spray-dried porcine plasma diluted in drinking acidified water for recovery of piglets with clinical signs of the Post-Weaning Multisystemic Wasting Syndrome (PMWS) was studied. The experiment was conducted in eight finishing units of an agroindustry of Santa Catarina State, Brazil, with positive diagnosis of PMWS by histopathology, immunohistochemistry (IHC) and polimerase chain reaction (PCR). The study was initiated around 14 days after the lodging of the piglets and concluded 42 days later. The experiment was randomly designed by weight and sex with two treatments: T1 - water ad libitum as a control group and T2 a solution constituted of porcine plasma (250g) in drinking acidified water (10L). The animals were distributed into two batch pens in the same facility with nine or ten piglets per pen, being one the control pen and the other one the treated pen. The following variables were evaluated: pH of water and solution; individual weight and clinical conditions of the piglets; solution intake within the period from 0 to 14 days, feed intake and feed conversion rate; mortality rate, histopathology and IHC analysis of the animals that died. The piglets of T2 presented clinical improvement during the 14 days of the experiment and a better feed conversion rate at 28 days of the experiment. Performance data did not show statistical difference between the trea

Estudou-se o efeito do plasma suíno spray-dried ultrafiltrado (AP920â) diluído em água de bebida acidificada com ácido Selkoâ-pH, para recuperação de leitões com sinais clínicos da Síndrome Multissistêmica do Definhamento (SMD). O experimento foi conduzido em oito unidades de terminação de uma agroindústria de Santa Catarina com confirmação da SMD pela histopatologia, imunoistoquímica (IHQ) e reação em cadeia da polimerase. As granjas manejavam as instalações no sistema de todos dentro todos fora com vazio sanitário de sete dias entre lotes. O estudo foi iniciado aos 14 dias após o alojamento dos leitões e finalizado 42 dias depois. O experimento foi delineado aleatoriamente por peso e sexo com dois tratamentos: T1 (controle) com água à vontade e T2 (tratado) com solução composta por 250g de plasma suíno em 10L de água de bebida acidificada com 12mL de ácido. Os animais foram distribuídos em duas baias na mesma instalação com nove ou dez leitões por baia, sendo uma controle e a outra tratado. As variáveis avaliadas foram: pH da água e da solução; peso individual e condição clínica dos leitões; consumo das soluções no período de 0 a 14 dias, consumo de ração e conversão alimentar; taxa de mortalidade, exame histopatológico e imunoistoquímico dos animais que morreram. Os leitões do T2 apresentaram melhora clínica nos 14 dias e melhor conversão alimentar nas avaliações aos 28 dias