Maternal transmission of Small Ruminant Lentivirus has no epidemiological importance.

The relative importance of maternal and horizontal transmission of small ruminant lentivirus (SRLV), the causative organism in maedi-visna, is poorly understood. Review of the literature shows that maternal transmission is inefficient, infecting only about 10-25 % of the lambs of infected ewes. Theory proves that maternal transmission alone cannot achieve the rates of transmission that would be required to start or maintain an outbreak. Maternal and horizontal transmission are additive in effect, and we use modelling to show that maternal transmission does not amplify or enhance prevalence in the presence of horizontal transmission. Taking steps to avoid maternal transmission by rearing lambs without infected maternal colostrum does have a role in producing a clean flock, but has no significance for the control of a disease outbreak if the conditions for horizontal transmission are present. Efforts to prevent disease by reducing the spread of SRLV must be focussed on minimising horizontal transmission.

Synergistic pathogenicity of vertically transmitted chicken infectious anemia virus and avian leukosis virus subgroup J coinfection in chickens.

Avian leukemia virus subgroup J (ALV-J) and chicken infectious anemia virus (CIAV) can be vertically transmitted; however, the pathogenicity of vertically transmitted coinfection with these 2 pathogens has not been studied. In this study, we created a model of chick morbidity in which chicks carried either ALV-J, CIAV, or both viruses via embryo inoculation. Thereafter, we analyzed the effects of vertically transmitted coinfection with CIAV and ALV-J on the pathogenicity of ALV-J and performed a purification assay based on hatching, mortality viremia positivity, and detection of fecal ALV-p27 antigen rates, and body weight. The hatching rate of the ALV-J+CIAV group was 68.57%, lower than those of the single infection and control groups. The survival curve showed that the mortality rates of the CIAV and ALV-J coinfection groups were higher than those of the single infection and control groups. Body weight statistics showed that coinfection aggravated the 7-d growth inhibition effect. The results of ALV-p27 antigen detection in cell culture supernatants showed that the positivity rates of the ALV-J and ALV-J+CIAV groups were 100% at all ages and 0% in the control group. The results of ALV-p27 antigen detection by anal swabs showed that the positivity rates of the ALV-J group were 92.86, 90.90, 88.89, and 93.33% at all ages, and that the ALV-J p27 positivity detection rate of anal swabs was lower than that of plasma virus isolation. The immune organ index of the ALV-J+CIAV group was significantly or very significantly lower than those of the single infection and control groups. The immune organ viral load showed that coinfection with CIAV and ALV-J promoted the proliferation of ALV-J and CIAV in immune organs. Coinfection with ALV-J and CIAV reduced chicken embryo hatchability and increased chick mortality and growth inhibition relative to their respective single infections. Additionally, coinfection with ALV-J + CIAV was even more detrimental in inducing immune organ atrophy (e.g., the thymus, spleen, and bursa), and promoted individual virus replication during coinfection.

Hemopathogens in naturally infected bovine fetuses in Brazil.

The transplacental transmission of parasites and hemoparasites is crucial for understanding the epidemiology of diseases. This study aimed to assess the prevalence of hemopathogens in bovine fetuses at various gestational periods. Samples were obtained from a slaughterhouse in the state of Minas Gerais, Brazil, and a total of 236 fetuses were collected. DNA extracted from blood samples (145) and organ samples (a pool of brain and spleen) (236) underwent a nested PCR (nPCR) assay to detect Babesia spp., Theileria spp., Trypanosoma vivax, Anaplasma marginale, Anaplasma bovis, Anaplasma phagocytophilum, Ehrlichia minasensis, and hemotropic Mycoplasma spp. Additionally, serological analysis of 145 plasma samples was conducted using the indirect fluorescent antibody test-IFAT to detect IgG against Babesia bovis, Babesia bigemina, A. marginale, and Trypanosoma vivax. The observed prevalence of transplacental transmission was 19.3 %, 6.2 %, 42.7 % and 2.7 %, for A. marginale, B. bigemina, 'Candidatus M. haemobos', and Mycoplasma wenyonii, respectively. The prevalence of A. marginale by gestational trimester was 16 % (13/81) in the second trimester and 23 % (14/60) in the third trimester, with no positive samples in the first trimester. Regarding the species B. bovis and B. bigemina, all evaluated animals tested negative by nPCR, and no serological evidence for B. bovis was found by the IFAT. Babesia bigemina demonstrated an overall seroprevalence of 6.2 % (9/145), with 4.8 % (7/145) in the last trimester and 1.3 % (2/145) in the second trimester of pregnancy. In total, 42.7 % (62/145) of blood samples were positive for 'Candidatus M. haemobos', with 42 % (34/81) in the middle trimester, and 43 % (26/60) in the final trimester of pregnancy. Mycoplasma wenyonni was detected in 2.7 % (4/145) blood samples, all in coinfection with 'C. M. haemobos'. The prevalence by pregnancy trimester was 25 % (1/4) in the first trimester; 1.2 % (1/81) in the second trimester and 3.3 % (2/60) in the third trimester of pregnancy. Hemopathogen DNA was detected in fetus blood samples but not the brain or spleen samples. All the samples were negative for T. vivax, Theileria spp., Anaplasma spp. and Ehrlichia spp. Overall, in this study, approximately 70 % of fetuses were positive for one or more of the studied parasites. No significant associations were observed between pairs of pathogens, except 'C. M. haemobos' and A. marginale.

Trypanosoma vivax in and outside cattle blood: Parasitological, molecular, and serological detection, reservoir tissues, histopathological lesions, and vertical transmission evaluation.

This study reports assessment of the sensitivity of diagnostic techniques to detect T. vivax in experimentally infected cattle. Additionally, it describes T. vivax extravascular parasitism during the acute and chronic phases of trypanosomosis and congenital transmission. The T. vivax diagnosis was compared using blood samples collected from the jugular, coccygeal and ear tip veins. For this study, 13 males and two females were infected with ≈ 1 × 106 viable T. vivax trypomastigotes (D0). One animal was kept as a negative control during the entire study. The 13 infected males were euthanized between 14 and 749 days post-infection (DPI). After confirming the cyclicity of both females (9 months of age), they were naturally mated with a bull. One female was euthanized at 840 DPI, and the other at 924 DPI. The two calves, one from each female, were euthanized at six months of age (924 DPI), and the negative control at 924 DPI. During this period, T. vivax in blood was assessed using direct methods (Woo test, cPCR, microscopic examination of fresh wet blood films and parasite quantification - Brener method), and serological methods (IFAT, ELISA, and IA). Tissue samples were collected from the liver, spleen, brain, cerebellum, heart, testicles, epididymis, kidneys, eyeballs, pre-scapular lymph nodes, ear tips, mammary glands, uterus, and ovaries. The protozoan DNA was examined using LAMP. There was no difference in the detection of T. vivax using the Woo test and Brener method among the jugular, coccygeal, and ear tip veins. The sensitivity of the detection methods varied depending on the disease phase. Direct methods (Woo test, Brener method, and cPCR) demonstrated higher sensitivity during the acute phase, while serological methods (IFAT, ELISA, and IA) were more sensitive during the chronic phase. Anti-T. vivax antibodies were detected up to 924 DPI. Tissue evaluation using LAMP demonstrated the presence of T. vivax DNA and associated histopathological changes up to 840 or 924 DPI. Only in mammary glands and ovaries was no DNA detected. The most frequently observed histopathological alteration was lymphohistioplasmocytic inflammatory infiltrate. No transplacental transmission of T. vivax was observed.

Effect of parity segregation on Mycoplasma hyopneumoniae infection dynamics and pneumonic lesions in pigs / Efeito da ordem de parto segregada sobre a dinâmica de infecção de Mycoplasma hyopneumoniae e lesões pulmonares ao abate

Gilts represent a group risk for Mycoplasma hyopneumoniae vertical transmission in swine herds. Therefore, parity segregation can be an alternative to control M. hyopneumoniae infections. The study evaluated the effect of parity segregation on M. hyopneumoniae infection dynamics and occurrence and severity of lung lesions at slaughter. For that, three multiple site herds were included in the study. Herd A consisted of the farm where gilts would have their first farrowing (parity order (PO) 1). After the first farrowing PO 1 sows were transferred to herd B (PO2-6). Herd C was a conventional herd with gilt replacement (PO1-6). Piglets born in each herd were raised in separated nursery and finishing units. Sows (n = 33 (A), 37 (B), 34 (C)) in all herds were sampled prior to farrowing and piglets (n = 54 (A), 71 (B), 66 (C)) were sampled longitudinally at 21, 63, 100, 140 days of age and at slaughter for M. hyopneumoniae detection by PCR and lung lesions scoring. M. hyopneumoniae prevalence in sows did not differ among herds. Prevalence of positive piglets was higher at weaning in the PO1 herd (A) (P < 0.05). However, prevalence of positive pigs from 100 days of age to slaughter age was higher in the PO2-6 herd (B) (P < 0.05). Lung lesion occurrence and severity were higher in herd B. The authors suggested that the lack of a proper gilt acclimation might have influenced the results, leading to sows being detected positive at farrowing, regardless of the parity.

As leitoas consistem em um grupo de risco na transmissão vertical de Mycoplasma hyopneumoniae dentro do sistema de produção de suínos. Dessa forma, a segregação de partos poderia ser utilizada como alternativa para controlar as infecções por M. hyopneumoniae. O objetivo deste estudo foi avaliar o efeito da segregação de partos sobre a dinâmica de infecção de M. hyopneumoniae e a ocorrência e severidade das lesões pulmonares ao abate. Para isso três sistemas de produção de suínos com três sítios cada foram incluídos no estudo. A granja A consistia da unidade onde as leitoas tem o primeiro parto, ou seja, alojava somente de fêmeas de ordem de parto 1 (Granja OP1). Após o primeiro parto as fêmeas OP1 foram transferidas para a granja B (Granja OP2-6), ou seja, consistia de fêmeas de ordem de parto 2 a 6, e a granja C consistiu em uma granja convencional com reposição de leitoas (Granja OP1-6), com fêmeas de ordem de parto 1 a 6. Os leitões nascidos de cada granja foram transferidos e criados em creches e terminações segregadas. As matrizes (n = 33 (A), 37 (B), 34 (C)) de todas as granjas do estudo foram amostradas previamente ao parto e os leitões (n = 54 (A), 71 (B), 66 (C)) foram amostrados longitudinalmente aos 21, 63, 100 e 140 dias de idade e ao abate. Em todos os momentos de coleta, as amostras foram avaliadas por PCR para detecção de M. hyopneumoniae. As lesões pulmonares foram avaliadas e escores de lesão foram atribuídos ao abate. A prevalência de matrizes positivas para M. hyopneumoniae não diferiu entre as granjas (P > 0,05). A prevalência ao desmame foi maior na granja A (OP1) (P < 0,05). No entanto, dos 100 dias de idade até o abate a prevalência de leitões positivos para M. hyopneumoniae foi maior na granja B (OP2-6) (P < 0,05). A ocorrência e severidade de lesões pulmonares foram maiores na granja B. Os autores sugerem que a falta de uma aclimatação adequada das leitoas pode ter influenciado nos resultados, levando à detecção de matrizes positivas ao parto, independente da ordem de parto.

Vertical transmission and kinetic of antibodies anti-Neospora caninum in naturally infected lambs in the semiarid region of Brazil / Transmissão vertical e cinética de anticorpos anti-Neospora caninum em cordeiros naturalmente infectados na região Semiárida do Brasil

Abstract Aimed with this study to evaluate vertical transmission of Neospora caninum in naturally infected sheep and to monitor the kinetics of antibodies against this protozoon in their lambs. Therefore, 48 pregnant ewes, from five herds, were divided into two groups: G1 - positive for anti-N. caninum antibodies, with 19 animals; and G2 - seronegative, with 29 animals. Blood samples were taken from the ewes and their lambs, immediately after birth, before ingesting colostrum, and 2, 7, 14, 21, 28, 35, 42, 49 and 56 days after birth. Analysis on serum antibodies was performed using the indirect immunofluorescent antibody test. Among the 19 seropositive mothers, six (31.6%) gave birth to lambs seropositive before ingesting colostrum and it was found that these lambs remained positive until the end of the study (56 days). Only one of the lambs, from a ewe that presented an antibody titer of 200, seroconverted after ingestion of colostrum. All the lambs that had been born from negative mothers remained negative throughout the experimental period. It was concluded that transplacental transmission was an important form of diffusion of N. caninum in the herds studied and that seropositive lambs maintained circulating antibodies during the period analyzed.

Resumo Objetivou-se avaliar a ocorrência da transmissão vertical de Neospora caninum em ovelhas naturalmente infectadas e monitorar a cinética de anticorpos para esse protozoário nos cordeiros. Portanto, foram selecionadas 48 matrizes prenhes, provenientes de cinco propriedades, e estas foram divididas em dois grupos: G1- 19 matrizes positivas para anticorpos anti-N. caninum antes da prenhez; e G2 - 29 matrizes soronegativas. Foram realizadas colheitas sanguíneas nas mães e cordeiros, no G1 e G2, imediatamente após a parição, antes da ingestão do colostro. Também foi possível realizar colheitas de sangue com 2, 7, 14, 21, 28, 35, 42, 49 e 56 dias após o nascimento. A pesquisa de anticorpos séricos foi realizada por meio da Reação de Imunofluorescência Indireta (RIFI). Das 19 matrizes soropositivas, seis (31,6%) pariram cordeiros soropositivos antes da ingestão do colostro, os quais mantiveram-se positivos até o final do experimento (56 dias). Apenas um dos cordeiros, filho de uma ovelha com título de anticorpos 200, soroconverteu após ingestão do colostro. Todos os cordeiros, filhos de mães negativas, mantiveram-se negativos durante todo o período experimental. Conclui-se que a transmissão transplacentária é uma importante forma de difusão do N. caninum nos rebanhos estudados e que os descendentes infectados, durante a gestação, mantiveram anticorpos circulantes durante o período analisado.

Transplacental transmission of Neospora caninum in naturally infected small ruminants from northeastern Brazil / Transmissão transplacentária de Neospora caninum em pequenos ruminantes infectados naturalmente do Nordeste do Brasil

Toxoplasma gondii and Neospora caninum are causative agents of abortion in sheep and goats. Thus, the present study aimed to describe the transplacental transmission of these protozoans in small ruminants of northeastern Brazil. Seventeen fetuses (6 goats and 11 sheep) from farms with history of abortion were necropsied and samples were collected from different tissues (brain, liver, lung, kidney and heart). The samples were analyzed by PCR, histopathology (HP) and immunohistochemistry (IHC) to evaluate whether T. gondii and/or N. caninum infection were the cause of abortion. None of the samples was positive for T. gondii according to PCR and IHC results. Some brain, liver, lung, kidney and heart samples of goat fetuses were positive for N. caninum by PCR. In the histopathology, mild mononuclear infiltration and necrosis with calcification were observed in the liver and brain of one goat fetus, respectively, that also was positive for N. caninum by PCR and IHC. The results confirmed vertical transmission of N. caninum in naturally infected goats of northeastern, Brazil.(AU)

Toxoplasma gondii e Neospora caninum são reconhecidos como protozoário causadores de aborto em ovinos e caprinos. Desta forma, objetivou-se descrever a transmissão transplacentária desses agentes em pequenos ruminantes na região Nordeste do Brasil. Foram examinados seis fetos caprinos e onze fetos ovinos, totalizando 78 amostras de diferentes tecidos (cérebro, fígado, pulmão, rim e coração) provenientes de propriedades rurais com histórico de aborto. As amostras foram analisadas por Reação em Cadeia da Polimerase (PCR), Histopatologia (HP) e Imunohistoquímica (IHQ), com a finalidade de associar o abortamento a T. gondii e/ou N. caninum. Nenhuma amostra foi positiva na PCR e IHQ para T. gondii. Algumas amostras de cérebro, fígado, pulmão, rim e coração de fetos de caprinos e ovinos foram positivas na PCR para N. caninum. Na histopatologia foi observado leve infiltrado mononuclear no fígado e necrose com calcificação no SNC de um caprino, associada à imunomarcação positiva para N. caninum na IHQ e PCR positiva. Os resultados confirmam a transmissão vertical de N. caninum em caprinos naturalmente infectados na região nordeste do Brasil.(AU)

Assessment of transplacental transmission of Neospora caninum in dairy cattle in the Agreste region of Pernambuco / Avaliação da transmissão transplacentária do Neospora caninum em bovinos de leite na região Agreste de Pernambuco

Abstract The transplacental transmission is the primary route of Neospora caninum infection in bovine herds around the world. This study aimed to determine the frequency of transplacental transmission of the parasite in dairy cattle of Agreste region of Pernambuco through serological tests (IFAT and ELISA). Three hundred sixteen serum samples from cows and heifers and their offspring were analyzed. The transplacental transmission rate was 72.22% (13/18) for cows and 69.23% (9/13) for heifers by IFAT. ELISA test showed transplacental transmission rate of 43.58% (17/39) for cows and 50% (9/18) for heifers. The transplacental transmission rates were similar, in both groups in test, but a higher seropositivity was found in cows by IFAT. Data were statistically analyzed using the chi-square and Fisher’s exact test. A significant relationship of dependence between seropositivity of mothers and their offspring was found. The more frequent IFAT antibody titers and ELISA levels for N. caninum were, respectively, 200 and between four (cows) and five (heifers and offspring). In the Spearman correlation, no association was found between the magnitude of antibody titers for N. caninum between mothers and their offspring. The kappa test showed an index of 0.35, indicating a mild correlation between the serological tests used. The study suggests that cows and heifers are the main transmitters of N. caninum in the studied region and that vertical transmission is the major form of transmission in dairy herds of the Agreste region of Pernambuco.

Resumo A transmissão transplacentária é a principal via de infecção do Neospora caninum nos rebanhos bovinos em todo o mundo. O presente estudo teve como objetivo determinar a frequência da transmissão transplacentária do parasita em bovinos leiteiros do Agreste Pernambucano, por meio de testes sorológicos (RIFI e ELISA). Foram analisadas 316 amostras de soro de fêmeas bovinas (vacas e novilhas) e de suas crias. A taxa de transmissão transplacentária pela RIFI foi de 72,22% (13/18) para vacas e 69,23% (9/13) para as novilhas. O ELISA teste mostrou taxa de transmissão transplacentária de 43,58% (17/39) para as vacas e 50% (9/18) para as novilhas. As taxas de transmissão transplacentária foram similares para os dois testes em geral, porém uma maior soropositividade foi encontrada nas vacas pela RIFI. Os dados foram estatisticamente analisados pelo teste de qui-quadrado e teste exato de Fischer. Foi encontrada uma relação significativa de dependência entre a soropositividade das mães e de suas crias. Os títulos de anticorpos anti- N. caninum foi de 200 na RIFI e posicionados entre o nível quatro (vacas) e cinco (novilhas e bezerros) pelo ELISA. Pela correlação de Spearman, não foi observada associação entre a magnitude de títulos de anticorpos anti- N. caninum de fêmeas com o de suas crias. O teste de concordância kappa revelou um índice de 0,35, indicando uma concordância leve entre os testes sorológicos utilizados. O estudo sugere que vacas e novilhas são as principais transmissoras do N. caninum na região estudada, sendo a transmissão vertical, a principal forma de transmissão do agente em rebanhos leiteiros do Agreste de Pernambuco.

Verificação da transmissão vertical de Neospora spp. em equinos / Verification of vertical transmission of Neospora spp. in horses.

O gênero protozoário Neospora é reconhecido como causador de desordens reprodutivas e abortos em bovinos. Entre os equinos pouco se sabe sobre os efeitos da infecção por estes protozoários. Atualmente é admitido que os efeitos da infecção por Neospora hughesi em equinos possam ocorrer no sistema nervoso central e, os efeitos provocados pela infecção por Neospora caninum recaiam sobre o sistema reprodutor de éguas. O presente trabalho verificou a presença de imunoglobulinas da classe G no soro sanguíneo de uma população de éguas de cria e, em seus respectivos potros antes da ingestão do colostro. Para execução deste trabalho foi empregada técnica de imunofluorescência indireta (RIFI), utilizando como antígeno taquizoítos de Neospora caninum, a diluição inicial dos soros das éguas foi de 1:50 e a diluição do soro dos potros empregada foi de 1:16. Foram assistidos 78 partos e todos os potros tiveram seu soro sanguíneo coletado imediatamente após o nascimento. A pesquisa de anticorpos contra Neospora spp. apontou que 50 (64%) éguas e 32 (41%) potros foram positivos. Das 50 éguas que apresentaram anticorpos contra Neospora spp. 24 geraram potros positivos. Entre as 28 éguas que não reagiram, oito deram a luz a potros positivos. De posse dos resultados encontrados podemos concluir que ocorreu a transmissão vertical de Neospora spp. nos equinos pesquisados...

The genre protozoan Neospora is recognized as causing reproductive disorders and miscarriages in cattle. Among the horses little is known about the effects of infection by these protozoa. It is currently accepted that the effects of infection by Neospora hughesi in horses may occur in the central nervous system, and effects of Neospora caninum infection occur in the reproductive system of mares. The present study examined the presence of class immunoglobulin G in blood serum of a population of brood mares and their foals before colostrum ingestion. For this assignment was employed indirect immunofluorescence assay (IFA) using as antigen tachyzoites of Neospora caninum, the initial dilution employed in sera of the mares was 1:50 and dilution in the serum of foals was 1:16. Were assisted 78 deliveries and all foals had their blood serum collected immediately after birth. The presence of antibodies against Neospora spp. found in mares was 50 (64%) and 32 (41%) foals were positive. Of the 50 mares that had antibodies to Neospora spp. 24 generated positive foals. Among the 28 mares unreacted eight gave birth to foals positive. Having the results we can conclude that vertical transmission occurred Neospora spp. researched in horses...

Transplacental transmission of Anaplasma marginale in beef cattle chronically infected in southern Brazil / Transmissão transplacentária de Anaplasma marginale em bovinos de corte cronicamente infectados no sul do Brasil

In this study, we have investigated the incidence of transplacental transmission of Anaplasma marginale in chronically infected cows with no history of acute anaplasmosis during gestation. In addition, we evaluated various techniques for detection of transplacental transmission of A. marginale. Blood samples were collected from 30 cows at three different periods: at the time of artificial insemination, at gestational diagnosis, and after calving. Also, blood was collected from the newborn calves, including one sample before colostrum intake, and another three days after birth. A. marginale-specific antibodies were detected in 100% of the cows with an indirect fluorescent antibody test (IFAT), and in 97% of them, using an indirect enzyme-linked immunosorbent assay (ELISA). Also, we observed that all of the three-day-old newborn calves were seropositive by IFAT. According to polymerase chain reaction, 63.3% of the cows were carriers of A. marginale, as well as 6.7% of the newborn calves. This represented a transplacental transmission rate of 10.5%. Furthermore, a correlation of 93.3% was observed between the two serodiagnostic techniques, demonstrating that both ELISA and IFAT can be used in epidemiological surveys of A. marginale. These results confirm the occurrence of transplacental transmission of A. marginale in chronically infected cows and suggest the importance of this transmission route in areas of enzootic instability.

O objetivo do estudo foi avaliar a transmissão transplacentária de A. marginale em bovinos de corte cronicamente infectados utilizando diferentes testes de diagnóstico. Amostras de sangue foram colhidas de trinta matrizes durante o período de inseminação artificial, no diagnóstico de gestação e após o parto. Foi colhido sangue dos bezerros antes da ingestão do colostro e três dias após o nascimento. Anticorpos foram detectados em 100% das matrizes pela Reação de Imunofluorescência Indireta (RIFI) e 97% pelo Ensaio de Imunoadsorção Enzimático Indireto (ELISA). Aos três dias de idade 100% dos bezerros estavam soropositivos na RIFI. Conforme os resultados da PCR, 63.3% das matrizes e 6.7% dos bezerros eram portadores do agente, representando taxa de transmissão transplacentária de 10.5%. Correlação de 93.3% foi observada entre os resultados das técnicas sorológicas, demonstrando que tanto ELISA quanto RIFI podem ser utilizadas em levantamentos epidemiológicos do agente. Os resultados confirmaram a transmissão transplacentária do agente em vacas cronicamente infectadas. Isto demonstra a importãncia desta via de transmissão do A. marginale em áreas de instabilidade enzoótica.

Respuesta humoral y consecuencias reproductivas en ovejas desafiadas con Brucella ovis al final de la gestación / Immune response and reproductive consequences in experimentally infected ewes with Brucella ovis during late pregnancy

La brucelosis ovina por Brucella ovis es una enfermedad de prevalencia alta en Argentina. Para evaluar la patogenicidad de B. ovis y la respuesta serológica durante el último mes de gestación, 6 ovejas se distribuyeron en dos grupos: G1, ovejas preñadas, n = 4 y G2, ovejas no preñadas, n = 2. Tres ovejas del G1 (15 días preparto) y una del G2 fueron inoculadas con B. ovis. Se analizaron muestras de suero mediante diferentes pruebas serológicas. Se realizó aislamiento y PCR a partir de mucus cérvico-vaginal (mcv), placenta y leche. En las muestras de placenta se realizó histopatología. Las hembras del G1 parieron corderos vivos; se detectaron anticuerpos en las ovejas desafiadas del G1 a partir de los 5 días posinoculación. El mcv de las ovejas desafiadas resultó negativo al aislamiento en ambos grupos. Las muestras de leche del G1 fueron positivas por cultivo y PCR a B. ovis. La técnica de PCR resultó positiva en las placentas de las ovejas desafiadas del G1. La histopatología reveló una placentitis necrótica supurativa en una de las ovejas desafiadas. El desafío con B. ovis preparto resultó en la invasión de la placenta y de la glándula mamaria, con la consecuente excreción de la bacteria por leche. La infección con B. ovis indujo una respuesta humoral temprana en las ovejas. La colonización de la placenta por B. ovis y la excreción de la bacteria por la leche sugieren un potencial riesgo de infección activa para los corderos y la posibilidad de que estos se comporten como portadores latentes de la infección.

Ovine brucellosis by Brucella ovis is a highly prevalent disease in Argentina. This study aimed to evaluate the pathogenicity of B. ovis and the serological response in ewes during late pregnancy and in their offspring. Six adult ewes were distributed in two groupsGI (pregnant females, n = 4) and G2 (nonpregnant females, n = 2). Three pregnant ewes at 15 days prepartum and one nonpregnant eve were inoculated with B. ovis. Sera of sheep and their offspring were analyzed by different serological tests. Samples of cervicovaginal mucus, placenta and milk were studied by bacteriology. A Brucella genus-specific PCR assay was carried out in placenta and milk samples. Placenta samples were hystopathologically processed. G1 females gave birth to live lambs, but one died hours postpartum. Serological techniques employed detected antibodies in serum of inoculated pregnant animal 5 days postchallenge. Sera of female controls G1 and G2 remained negative throughout the study. Cervicovaginal mucus of infected ewes in G1 and G2 yielded negative results to bacteriology, but B. ovis was isolated from milk. The PCR assay was positive for the placenta and milk from inoculated pregnant ewes. Histopathology revealed necrotic suppurative placentitis in one placenta. However, although results demonstrated that B. ovis can invade the placenta and mammary gland, this bacterium did not cause abortion when it was inoculated intravenously at 15 days prepartum. B. ovis infection induced an early humoral response in pregnant ewes, but their lambs remained seronegative, indicating that there was no transfer of antibodies in infancy. Placenta colonization and milk excretion of B. ovis involves a potential source of infection for lambs, which could play a role as latent carriers of infection.

Respuesta humoral y consecuencias reproductivas en ovejas desafiadas con Brucella ovis al final de la gestación / Immune response and reproductive consequences in experimentally infected ewes with Brucella ovis during late pregnancy

La brucelosis ovina por Brucella ovis es una enfermedad de prevalencia alta en Argentina. Para evaluar la patogenicidad de B. ovis y la respuesta serológica durante el último mes de gestación, 6 ovejas se distribuyeron en dos grupos: G1, ovejas preñadas, n = 4 y G2, ovejas no preñadas, n = 2. Tres ovejas del G1 (15 días preparto) y una del G2 fueron inoculadas con B. ovis. Se analizaron muestras de suero mediante diferentes pruebas serológicas. Se realizó aislamiento y PCR a partir de mucus cérvico-vaginal (mcv), placenta y leche. En las muestras de placenta se realizó histopatología. Las hembras del G1 parieron corderos vivos; se detectaron anticuerpos en las ovejas desafiadas del G1 a partir de los 5 días posinoculación. El mcv de las ovejas desafiadas resultó negativo al aislamiento en ambos grupos. Las muestras de leche del G1 fueron positivas por cultivo y PCR a B. ovis. La técnica de PCR resultó positiva en las placentas de las ovejas desafiadas del G1. La histopatología reveló una placentitis necrótica supurativa en una de las ovejas desafiadas. El desafío con B. ovis preparto resultó en la invasión de la placenta y de la glándula mamaria, con la consecuente excreción de la bacteria por leche. La infección con B. ovis indujo una respuesta humoral temprana en las ovejas. La colonización de la placenta por B. ovis y la excreción de la bacteria por la leche sugieren un potencial riesgo de infección activa para los corderos y la posibilidad de que estos se comporten como portadores latentes de la infección.(AU)

Ovine brucellosis by Brucella ovis is a highly prevalent disease in Argentina. This study aimed to evaluate the pathogenicity of B. ovis and the serological response in ewes during late pregnancy and in their offspring. Six adult ewes were distributed in two groupsGI (pregnant females, n = 4) and G2 (nonpregnant females, n = 2). Three pregnant ewes at 15 days prepartum and one nonpregnant eve were inoculated with B. ovis. Sera of sheep and their offspring were analyzed by different serological tests. Samples of cervicovaginal mucus, placenta and milk were studied by bacteriology. A Brucella genus-specific PCR assay was carried out in placenta and milk samples. Placenta samples were hystopathologically processed. G1 females gave birth to live lambs, but one died hours postpartum. Serological techniques employed detected antibodies in serum of inoculated pregnant animal 5 days postchallenge. Sera of female controls G1 and G2 remained negative throughout the study. Cervicovaginal mucus of infected ewes in G1 and G2 yielded negative results to bacteriology, but B. ovis was isolated from milk. The PCR assay was positive for the placenta and milk from inoculated pregnant ewes. Histopathology revealed necrotic suppurative placentitis in one placenta. However, although results demonstrated that B. ovis can invade the placenta and mammary gland, this bacterium did not cause abortion when it was inoculated intravenously at 15 days prepartum. B. ovis infection induced an early humoral response in pregnant ewes, but their lambs remained seronegative, indicating that there was no transfer of antibodies in infancy. Placenta colonization and milk excretion of B. ovis involves a potential source of infection for lambs, which could play a role as latent carriers of infection.(AU)

Neospora caninum: evaluation of vertical transmission in slaughtered dairy cows (Bos taurus) / Neospora caninum: avaliação da transmissão vertical em vacas leiteiras (Bos taurus)

Neospora caninum is a worldwide parasite recognized as one of the main parasites responsible for abortion in cattle. The objective of this study was to evaluate vertical transmission of N. caninum in dairy cows (Bos taurus) that were slaughtered at an abattoir in the state of Santa Catarina, southern Brazil. Blood samples (with and without EDTA) from 60 pregnant dairy cows and blood and tissue samples (brain, lung, heart and liver) from their fetuses were collected and used for PCR and serological evaluation. Blood samples from 60 non-pregnant cows were collected and used to detect antibodies. Anti-N. caninum antibodies were detected by indirect ELISA. Antibodies against N. caninum were observed in 41.6% (25∕60) of the pregnant cows and in 43.3% (26∕60) of the non-pregnant cows. Antibodies against the parasite were detected in sera from three fetuses (5.5%). PCR analysis revealed that 3.3% (2∕60) of the cows and 6.6% (4∕60) of the fetuses evaluated were positive for specific N. caninum primers. These positive fetuses were between 4-6 months of age. Therefore, considering PCR and serological tests to be indicative of vertical transmission in fetuses, 11.6% (7∕60) of the fetuses were infected by N. caninum during gestation.

Neospora caninum é um parasita de distribuição mundial reconhecido como um dentre os principais parasitas, responsável por abortamento em bovinos. O objetivo deste estudo foi avaliar a transmissão vertical de N. caninum em vacas leiteiras (Bos taurus) que foram submetidas ao abate em matadouro no Estado de Santa Catarina, sul do Brasil. Sangue (com e sem EDTA) de 60 vacas leiteiras prenhas e amostras de sangue e tecidos (cérebro, pulmão, coração e fígado) de seus fetos foram coletados e utilizados para PCR e avaliação sorológica. Amostras de sangue de 60 vacas não-gestantes foram obtidas e utilizadas para detecção de anticorpos. A detecção de anticorpos séricos anti-N. caninum foi avaliada pelo ELISA-teste indireto. Anticorpos anti-N. caninum foram observados em 41,6% (25∕60) das vacas prenhas e em 43,3% (26∕60) das vacas não-gestantes. Três fetos (5,5%) foram soros positivos para N. caninum. Análise pela PCR revelou que 3,3% (2∕60) das vacas e 6,6% (4∕60) dos fetos avaliados foram positivos paraN. caninum. As idades dos fetos positivos eram de 4 a 6 meses. Portanto, considerando a PCR e a sorologia como indicativo de transmissão vertical em fetos, 11,6% (7∕60) dos fetos foram infectados por N. caninum durante a gestação.

Respuesta humoral y consecuencias reproductivas en ovejas desafiadas con Brucella ovis al final de la gestación. / [Immune response and reproductive consequences in experimentally infected ewes with Brucella ovis during late pregnancy].

Ovine brucellosis by Brucella ovis is a highly prevalent disease in Argentina. This study aimed to evaluate the pathogenicity of B. ovis and the serological response in ewes during late pregnancy and in their offspring. Six adult ewes were distributed in two groupsG1 (pregnant females, n = 4) and G2 (nonpregnant females, n = 2). Three pregnant ewes at 15 days prepartum and one nonpregnant eve were inoculated with B. ovis. Sera of sheep and their offspring were analyzed by different serological tests. Samples of cervicovaginal mucus, placenta and milk were studied by bacteriology. A Brucella genus-specific PCR assay was carried out in placenta and milk samples. Placenta samples were hystopathologically processed. g1 females gave birth to live lambs, but one died hours postpartum. Serological techniques employed detected antibodies in serum of inoculated pregnant animal 5 days postchallenge. sera of female controls G1 and G2 remained negative throughout the study. Cervicovaginal mucus of infected ewes in G1 and G2 yielded negative results to bacteriology, but B. ovis was isolated from milk. The PCR assay was positive for the placenta and milk from inoculated pregnant ewes. Histopathology revealed necrotic suppurative placentitis in one placenta. However, although results demonstrated that B. ovis can invade the placenta and mammary gland, this bacterium did not cause abortion when it was inoculated intravenously at 15 days prepartum. B. ovis infection induced an early humoral response in pregnant ewes, but their lambs remained seronegative, indicating that there was no transfer of antibodies in infancy. Placenta colonization and milk excretion of B. ovis involves a potential source of infection for lambs, which could play a role as latent carriers of infection.

Quando eu descobri tive um baque: os desafios da prevenção da transmissão vertical do HIV

A eficácia da quimioprofilaxia da transmissão vertical do HIV tem contribuído para minimizar o numero de crianças infectadas pelo vírus. No entanto é essencial para essa finalidadeo uso correto do protocolo pela mãe. Mas onde estão as falhas desse processo? Porque ainda há crianças sendo desnecessariamente expostas ao vírus HIV? Foi objetivo desse estudo conhecer as concepções sobre gravidez, HIV/AIDS e transmissão vertical de gestantes e mães soropositivas. A partir disso, fornecer subsídios para o aperfeiçoamento da prevenção da transmissão vertical. Partiu-se da hipótese de que aspectos sociais, culturais e econômicos das mulheres podem estar envolvidos na adesão ou não da prevenção da transmissão vertical da AIDS. Quatorze mulheressoropositivas, sendo onze com filhos já nascidos e três gestantes, deram seus depoimentos através de entrevistas semi-estruturadas orientadas por roteiro. Os Fatores sócio culturais das mulheres não foram investigados de forma direta, mas foi possível registrar através das falas uma possívelassociação destes com a quimioprofilaxia da transmissão vertical do HIV. Ainda que de forma incompleta todas realizaram a quimioprofilaxia, com exceção de uma mulher que teve odiagnostico somente após o parto. Através da análise dos depoimentos foi possível identificar que as mulheres que possuíam nível sócio cultural mais elevado demonstraram maior domínio quanto à importância do tratamento, embora a principal motivação para a realização do tratamento tenhasido a não contaminação de seus filhos. Foram descritos alguns determinantes envolvidos na adesão das mulheres ao tratamento, dentre eles; o conhecimento acerca do tratamento e aspectosligados aos serviços de saúde. Algumas falhas no pré-natal foram apontadas como ponto negativo neste processo. Dentre os resultados encontrados ocasionalmente foi ressaltado a forma que os companheiros reagiram à doença...

Quantification of vertical transmission of Neospora caninum in dairy cows in Minas Gerais, Brazil / Quantificação da transmissão vertical de Neospora caninum em vacas leiteiras de Minas Gerais, Brasil

The objective of this cross-sectional study was to estimate the rate of vertical transmission and to investigate horizontal transmission of Neospora caninum and occurrences of reproductive abnormalities in seropositive dairy cows on two farms in the state of Minas Gerais, Brazil. The frequency of cows seropositive for N.caninum according to the indirect fluorescent antibody test (IFAT) was 39.4% (93/236) for Farm A and 31.4% (32/102) for the Farm B (p > 0.05). The mean vertical transmission rates for N. caninum were 29% and 9% for the herds of Farms A and B, respectively. No negative effects (p > 0.05) from infection by N.caninum were observed regarding milk production and occurrences of reproductive abnormalities in herds A and B.

O objetivo deste estudo transversal foi estimar a taxa de transmissão vertical e investigar a transmissão horizontal de Neospora caninum, e a ocorrência de alterações reprodutivas em vacas leiteiras soropositivas em duas fazendas no Estado de Minas Gerais, Brasil. A frequência de vacas soropositivas a N. caninum pelo teste de imunofluorescência indireta (RIFI) foi de 39,4% (93/236) e 31,4% (32/102) para as fazendas A e B, respectivamente. A taxa média de transmissão vertical de N. caninum, respectivamente, foi de 29% e 9% para os rebanhos A e B. Não foi observado nenhum efeito negativo (p > 0,05) da infecção por N. caninum sobre a produção de leite e a ocorrência de alterações reprodutivas nos rebanhos A e B.

Rabies virus in a pregnant naturally infected southern yellow bat (Lasiurus ega)

Current knowledge on bat lyssavirus infections in their native hosts is limited and little is known about the virulence, virus dissemination and transmission among free-living insectivorous bats. The present study is a brief description of rabies virus (RABV) dissemination in tissues of a naturally infected pregnant southern yellow bat (Lasiurus ega) and its fetuses, obtained by reverse-transcriptase polymerase chain reaction (RT-PCR). The RT-PCR was positive in samples from the brain, salivary gland, tongue, lungs, heart, kidneys and liver. On the other hand, the placenta, three fetuses, spleen, intestine and brown fat tissue tested negative. This research demonstrated the absence of rabies virus in the fetuses, thus, in this specific case, the transplacentary transmission was not observed.

Neosporose equina: ocorrência de anticorpos anti-Neospora spp. e associação entre status sorológico de éguas e de suas crias / Equine neosporosis: occurrence of antibodies against Neospora spp. and association between the serological status of the mares and of their offspring

Os protozoários Neospora caninum e N. hughesi infectam os equinos e podem provocar diferentes sinais clínicos associados a problemas reprodutivos ou a distúrbios neurológicos, respectivamente. A patogenia da neosporose é pouco conhecida nos equinos, bem como as fontes de infecção horizontal de N. hughesi. Além disso, há dúvidas quanto ao papel da transmissão vertical de Neospora spp. na sua manutenção em populações equinas. Neste estudo avaliaram-se: (1) a ocorrência da infecção por Neospora spp. na população de éguas em idade reprodutiva em um haras de cavalos da raça Crioula; e (2) a possível associação entre o status sorológico destas éguas com o de suas crias, como meio de investigar, indiretamente, a relevância da transmissão transplacentária na ocorrência da infecção por Neospora spp. nestes animais. A associação entre o status sorológico das éguas e o de suas crias foi altamente significativa. Os animais descendentes de éguas soropositivas tiveram maior ocorrência de anticorpos anti-Neospora spp. do que os descendentes de éguas soronegativas, embora expostos aos mesmos fatores de risco ambientais. A associação entre parentesco em primeiro grau e status sorológico indica a influência da infecção vertical (transplacentária) na ocorrência de Neospora spp. na população equina estudada.

Neospora caninum and N. hughesi are protozoa which can infect horses and can cause reproductive and neurological diseases, respectively. The pathogenesis of neosporosis in horses is poorly understood, as well as the sources of horizontal infection of N. hughesi. Furthermore, there are doubts about the role of the vertical transmission of Neospora spp. in maintenance of these parasites in equine populations. In this study, we evaluated: (1) the occurrence of infections by Neospora spp. in a population of mares (in reproductive age) on a farm of Crioula breed horses; and (2) the possible association between the serological status of mares and of their offspring, aiming to investigate, indirectly, the relevance of transplacental transmission for the occurrence of Neospora spp. in these horses. We found a highly significant association between the serological status of mares and their offspring. Although had been exposed to the same environmental risk factors, the descendants of seropositive mares had a higher percentage of seropositivity against Neospora spp. compared to the descendants of seronegative mares. The association between kinship and serological status indicates an influence of vertical (transplacental) infection raising the occurrence of Neospora spp. in the studied equine population.