Transplacental transmission of cutaneous Leishmania mexicana strain in BALB/c mice.

The vertical transmission of leishmaniasis has been reported in species that cause visceral leishmaniasis. However, this condition has scarcely been documented in species that cause cutaneous leishmaniasis. The aim of this study was to determine experimentally whether L. mexicana is transmitted vertically. A control group of BALB/c mice and a group infected with L. mexicana were mated, the gestation was monitored, and females were killed before delivery. Four resorptions (P = 0.023) and eight fetal deaths (P = 0.010) were observed in the infected female group; furthermore, the offspring body weight of the infected group was lower than the body weight of the healthy group (P = 0.009). DNA amplification by polymerase chain reaction (PCR) revealed that all placentas and maternal spleens as well as 39 of 110 fetal spleens obtained from the offspring of infected mothers tested positive for Leishmania. In conclusion, L. mexicana is transmitted transplacentally and causes fetal death, resorption, and reduction in offspring body weight.

The Neospora caninum-Spain 7 isolate induces placental damage, fetal death and abortion in cattle when inoculated in early gestation.

The Nc-Spain 7 isolate of Neospora caninum, which was newly obtained from an asymptomatic congenitally infected calf, demonstrated a similar virulence as Nc-1 strain in mouse models. The aim of this study was to characterize the pathogenesis of Nc-Spain 7 isolate in cattle after experimental infection at 65 days of gestation. For this purpose, thirteen pregnant heifers were divided into three groups as follows: group A: 7 heifers inoculated with 1 × 10(8) tachyzoites of Nc-Spain 7 isolate; group B: 4 heifers inoculated with 1 × 10(8) tachyzoites of Nc 1 strain; and group C: 2 heifers received PBS. Serum samples were collected weekly and heparinized blood samples were collected three times (0, 28 and 42 days after inoculation) by jugular venipuncture. Placenta and fetal tissue samples were collected at time of necropsy. Specific antibody response in the dams was tested by IFAT, indirect ELISA, and rNcGRA7 and rNcSAG4 based-ELISA. Specific antibody response in fetal fluids was tested by IFAT. IFN-γ production was measured after in vitro culture of PBMC and the supernatant was assessed using a commercial kit (BOVIGAM). A significant increase in N. caninum antibody responses was detected in groups A and B by IFAT and by i-ELISA from day 14 after inoculation onwards. Besides, antibody response against rNCGra7 protein was also detected in all inoculated heifers by rNcGra7-based ELISA. Four fetuses from group A and one from group B were aborted between 3 and 5 weeks after infection. In the recovered fetuses, only 3 out of 4 fetal fluids from fetuses of group A and 1 out of 3 of group B were seropositive by IFAT, but all of them were positive by PCR. Transplacental transmission could be determined in all fetuses from groups A and B by PCR and/or IHC. Heifers of group C and their fetuses remained negative by all techniques. The results of this study demonstrate that the NC-Spain 7 isolate could be transmitted transplacentally, and produced fetal death and abortion in cattle.

Effects of Neospora caninum infection at mid-gestation on placenta in a pregnant mouse model.

Neospora caninum is one of the more-efficient transplacentally-transmitted organisms. The goal of the present study was to investigate the pathologic and immunologic changes that occur at the materno-fetal interphase in pregnant BALB/c mice infected with N. caninum at mid-gestation. Parasite DNA was detected in feto-placentary units 3 days post-infection (PI). On day 7 PI, the DNA detection level and parasite burden were significantly higher in the placentas than in the fetuses, which may indicate that the parasite is mainly multiplying in the placenta during the initial infection. In the spleens of infected dams, we observed an increase in IFN-γ, IL-10, and IL-4. However, only IL-4 was upregulated in placentas from the infected dams; this may enhance susceptibility to N. caninum at the materno-fetal interphase and favor transmission to the progeny. Finally, an increase in TNF-α expression in nested-PCR-positive placentas combined with necrosis may compromise the viability of the fetuses.

Fetal death in cows experimentally infected with Neospora caninum at 110 days of gestation.

Neospora caninum is a major cause of abortion in cattle, but the reasons why some animals abort and not others remain unclear. Most of the N. caninum experimental primary infections in cattle late in gestation, after 120 days of pregnancy, result in birth of full-term congenitally infected fetuses. In the present study, the distribution of parasites and pathogenesis of infection in both dams and fetuses after inoculation with 10(7) culture derived tachyzoites of N. caninum NC-Illinois cattle strain at 110 days of gestation were analyzed at 3 weeks, 6 weeks and 9 weeks after infection (WAI) in eight Angus heifers. One dam from the group euthanized at 6 WAI had a dead fetus at necropsy. Extensive lesions were observed in the placenta and tachyzoites were detected in both the placenta and the fetus. The fetus was seropositive and had high IFN-gamma g production in fetal fluids. Another fetus, still alive when euthanized at 3 WAI, had severe lesions and high IFN-gamma production and a similar fate could have been expected if the experimental period would have been longer. Lesions in the placenta of the remaining six dams that had live fetuses at necropsy were mild. In those dams, the fetal and maternal placentas had not separated and contained focal areas of placentitis at the materno-fetal junction. Transplacental infection took place on all fetuses based on detection of parasitic DNA in fetal tissues. The present study shows that experimental N. caninum infection of naïve dams after 110 days of pregnancy can lead to fetal death. The results suggest that the severity of placental lesions and the strong IFN-gamma response in some fetuses, possibly as part of the immune response trying to control the high parasitemia, might, in fact, be the cause of their death.

Vaccination with recombinant NcROP2 combined with recombinant NcMIC1 and NcMIC3 reduces cerebral infection and vertical transmission in mice experimentally infected with Neospora caninum tachyzoites.

We investigated the protective potential of recombinant his-tagged antigens recNcMIC1, recNcMIC3 and recNcROP2, applied either as single vaccines or as vaccine combinations, in BALB/c mouse models for cerebral and fetal infection. Subsequently, mice were mated and challenged by i.p. inoculation of 2 x 10(6)Neospora caninum tachyzoites at day 7 of pregnancy. The mortality and morbidity of adult mice (non-pregnant and dams) and of the newborn pups was studied for a period of 40 days following birth. Vaccination of non-pregnant mice with recNcROP2 or combinations of recNcROP2 with recNcMIC antigens significantly reduced the numbers of mice suffering from clinical signs, and morbidity was completely prevented with the combination of all three antigens. Of the dams, the groups receiving either recNcROP2 alone or the combination of all three antigens did not exhibit any morbidity, the groups receiving ROP2 mixed with either MIC1 or MIC3 exhibited reduced numbers of deaths, and in the infection control group and the adjuvant group 50% and 43% of mice, respectively, succumbed to disease. For pups, the highest survival rates were noted for the groups receiving recNcROP2 (50%) and recNcROP2/NcMIC1/NcMIC3 (35%), while in the infection- and adjuvant- control groups all pups died, the latest at days 25 and 30, respectively. Quantification of parasite DNA by N. caninum-specific real-time PCR revealed consistently lower parasite burdens in brain tissue of pups from vaccinated groups compared with the controls. However, dense granule antigen 2 (GRA2) real-time reverse transcriptase-PCR on brain tissue of surviving pups (applied here to detect viable parasites) demonstrated that only the pups from the group vaccinated with all three antigens in combination appeared free of viable tachyzoites, while in all other groups viable parasites were still present. Serological analysis of humoral (total IgG, IgG1 and IgG2a) and serum cytokine (IL-4 and IFN-gamma) responses showed that this effect was associated with a Th-2-biased immune response, with a clearly elevated IL-4/IFN-gamma ratio in the mice receiving all three antigens in combination. In conclusion, a mixture of recombinant antigens representing important secretory micronemal and rhoptry proteins leads to a significant protection against vertical transmission of N. caninum in mice.

Upregulation of cytokines is detected in the placentas of cattle infected with Neospora caninum and is more marked early in gestation when fetal death is observed.

The protozoan parasite Neospora caninum causes fetal death after experimental infection of pregnant cattle in early gestation, but the fetus survives a similar infection in late gestation. An increase in Th1-type cytokines in the placenta in response to the presence of the parasite has been implicated as a contributory factor to fetal death due to immune-mediated pathological alterations. We measured, using real-time reverse transcription-PCR and enzyme-linked immunosorbent assay, the levels of cytokines in the placentas of cattle experimentally infected with N. caninum in early and late gestation. After infection in early gestation, fetal death occurred, and the levels of mRNA of both Th1 and Th2 cytokines, including interleukin-2 (IL-2), gamma interferon (IFN-gamma), IL-12p40, tumor necrosis factor alpha (TNF-alpha), IL-18, IL-10, and IL-4, were significantly (P < 0.01) increased by up to 1,000-fold. There was extensive placental necrosis and a corresponding infiltration of CD4(+) T cells and macrophages. IFN-gamma protein expression was also highly increased, and a modest increase in transforming growth factor beta was detected. A much smaller increase in the same cytokines and IFN-gamma protein expression, with minimal placental necrosis and inflammatory infiltration, occurred after N. caninum infection in late gestation when the fetuses survived. Comparison of cytokine mRNA levels in separated maternal and fetal placental tissue that showed maternal tissue was the major source of all cytokine mRNA except for IL-10 and TNF-alpha, which were similar in both maternal and fetal tissues. These results suggest that the magnitude of the cytokine response correlates with but is not necessarily the cause of fetal death and demonstrate that a polarized Th1 response was not evident in the placentas of N. caninum-infected cattle.

Impact of fetal and neonatal viral (and parasitic) infections on later development and disease outcome.

It is estimated that there are 4 million neonatal deaths and an equal number of stillbirths annually, the majority in the developing world. Neonatal deaths account for one third of deaths in children less than 5 years of age, and at least one third of neonatal deaths are related to infections. Infections also account for 80% of deaths in the postneonatal period through 5 years of age. There are several viral and parasitic infections which produce fetal and neonatal morbidity and mortality. Neonatal infections occur during one or more perinatal periods: in utero (congenital), intrapartum (during labor and delivery), and early or late postpartum. Here the term perinatal refers to all of these stages of fetal or neonatal infections. The mechanisms of perinatal viral and parasitic infections vary depending on the specific pathogen, however, all begin with maternal infection. Following maternal infection, organisms may produce indirect placental infection with or without fetal infection, direct fetal or neonatal infection, or primary maternal infection and subsequent perinatal sequelae without either placental or fetal infection. Some pathogens may produce infections by more than one mechanism. This brief report will provide an overview of the pathogenesis, general outcomes, and known pathogens associated with perinatal viral and parasitic infections.

The extent of parasite-associated necrosis in the placenta and foetal tissues of cattle following Neospora caninum infection in early and late gestation correlates with foetal death.

The protozoan parasite Neospora caninum is the most frequently diagnosed abortifacient in the UK and a leading cause of abortion worldwide but the mechanisms leading to abortion are not fully understood. The distribution of parasites and the histopathological changes in the placenta and foetus were compared in 12 cows following experimental infection of cattle with N. caninum in early (n=6) and late (n=6) gestation, by PCR, immunohistology, light microscopy and transmission electron microscopy. Twelve uninfected pregnant cattle were used as controls. Infection in early gestation led to foetal death. In the placentae of cattle immediately following foetal death, N. caninum DNA was detected and there was evidence of widespread parasite dissemination. This was associated with extensive focal epithelial necrosis, serum leakage and moderate maternal interstitial mononuclear cell infiltration. In the foetuses, parasites were evident in all tissues examined and were associated with necrosis. In the placenta of cattle infected in late gestation, N. caninum DNA was detected sporadically but parasites were not evident immunohistologically. Small foci of necrosis were seen associated with mild interstitial mononuclear cell infiltration. Detection of N. caninum DNA in the foetuses was sporadic and parasites were demonstrated immunohistologically in brain and spinal cord only, with an associated mononuclear cell infiltration. This data is consistent with uncontrolled parasite spread in an immunologically immature foetus and could, via multiparenchymal necrosis of foetal tissues or the widespread necrosis and inflammation observed in the placenta, be the cause of Neospora-associated abortions.

Aborto ovino associado com infecção por Sarcocystis sp / Ovine abortion associated with Sarcocystis sp. infection

Infecções por protozoários têm distribuição mundial e podem causar aborto, nascimentos prematuros e ou morte fetal em diversas espécies animais. Em julho de 2004, oito ovinos Corriedale apresentaram problemas reprodutivos caracterizados por aborto e natimortalidade no terço final da gestação. Dessas oito perdas, um natimorto macho foi enviado ao Setor de Patologia Veterinária para necropsia. Alterações macroscópicas não foram observadas durante a necropsia. Lesões histológicas foram observadas principalmente no cérebro e coração e se caracterizaram por encefalite não-supurativa multifocal acentuada associada à presença de protozoários no interior de células endoteliais e vasos sanguíneos e miocardite não-supurativa focal leve. Alguns desses organismos apresentaram formato de roseta. O teste de imunoistoquímica anti-Toxoplasma gondii foi negativo, mas houve reação cruzada com anticorpo anti-Neospora caninum. O exame de imunofluorescência direta para Leptospira sp. foi negativo. A bacteriologia aeróbica e micro-aeróbica não revelou crescimento significativo. Esses achados foram compatíveis com o diagnóstico de Sarcocystis sp.

Protozoal infection has worldwide distribution and may cause abortion, premature parturition or fetal death in almost all domestic animals. In July 2004, eight Corriedale sheep showed abortion and stillbirth in the third trimester of gestation. Of these reproductive losses, one stillborn male was submitted to the Laboratory of Veterinary Pathology for necropsy investigation. The direct immunofluorescence test for Leptospira sp. was negative. No significant bacteria was isolated from lung and liver by aerobic and microaerobic cultures. Macroscopic lesions were not found in any fetal tissue. The histological lesions were observed mainly in the brain and heart and consisted primarily of severe multifocal nonsupurative encephalitis and nonsuppurative myocarditis. Schizonts of a protozoan parasite consistent with Sarcocystis sp. were found in the endothelial cells and vascular endothelium in several organs. Many schizonts with merozoites arranged in a rosette-like pattern were observed in brain and kidney tissues. In sections stained with periodic acid-Schiff (PAS), the limiting membrane of some schizonts appeared to be weakly PAS-positive. Merozoites and nuclei were PAS-negative. Protozoa did not react immunohistochemically to the antibody anti-Toxoplasma gondii; however, cross-reactivity was observed with Neospora caninum antibody. These findings were consistent with the diagnosis of Sarcocystis sp.

Immunization of cattle with live tachyzoites of Neospora caninum confers protection against fetal death.

Neospora caninum is an obligate intracellular protozoan parasite that causes abortion in cattle. It is normally found as a latent infection controlled by a T-helper-cell type 1 response involving CD4(+) cytotoxic T cells and gamma interferon. Cattle may be infected by two different routes: transplacentally as a result of activation of the latent infection in the mother causing congenital infection or abortion and by ingestion of oocysts, which, if it occurs during gestation, can also result in abortion. Here, for the first time, we establish proof that live vaccination protects against fetal death, whereas immunization using whole-tachyzoite lysate in different adjuvants fails to protect against fetal death. Strong antibody responses were induced in all the vaccinated groups, and the quality and magnitude of these responses were similar in the live- and the lysate-vaccinated groups. In contrast, only the group immunized with live tachyzoites had strong cellular and gamma interferon responses prior to challenge, and these responses correlated with protection against fetopathy. These results suggest that a cellular immune response may be important in the mechanisms involved in protection against N. caninum-associated abortions.

The role of soluble tumor necrosis factor receptor types I and II and tumor necrosis factor-alpha in malaria during pregnancy.

In a prospective study of rhesus monkeys inoculated with Plasmodium coatneyi or saline on an infection/gestational timeline, we determined the serum levels of tumor necrosis factor-alpha (TNF-alpha), soluble tumor necrosis factor receptor type I (sTNFR-I), and soluble tumor necrosis factor receptor type II (sTNFR-II) in peripheral blood throughout primigravid pregnancy, malaria infection, and a combination of the two. Our goal was to determine the association between levels of TNF-alpha and of its 2 soluble receptors and the course of pregnancy and/or malaria and infant outcome. We found that any detectable level of TNF-alpha was always associated with fetal death and that the sTNFRs may be important for fetal protection, possibly through neutralizing the toxic effects of TNF-alpha. Our findings also showed that increased levels of sTNFR-II were associated specifically with malaria and not with normal pregnancy or even pregnancy with low birth weight due to other causes. In contrast, increases in sTNFR-I levels during the later half of normal pregnancies indicate that sTNFR-I may be important in regulating TNF-alpha levels in preparation for normal labor and delivery.

Neosporosis in dairy cattle: an update from an epidemiological perspective.

Our understanding of the epidemiology of bovine neosporosis is advancing rapidly with considerable research activity being facilitated by improving methods. The dynamics of the infection in the known definitive hosts, the dog and the coyote, are being described. Improved procedures for production of oocysts enables the horizontal transmission to intermediate hosts and the subsequent more natural infection process to be studied. Details of the sylvatic cycles, potentially involving other animals in the dairy environment, are also emerging.

Comparative effect of Neospora caninum infection in BALB/c mice at three different gestation periods.

Neospora caninum has been recognized as a major cause of infectious bovine abortion worldwide. In the present study, the effect of N. caninum infection in mice at the 3 gestation periods (first, second, and third period) was investigated. In dams, tissue distribution of N. caninum was evaluated by nested polymerase chain reaction. In the progeny, fetal mortality, stillbirth, litter size, neonatal mortality/morbidity, vertical transmission, and parasite burden in neonatal tissues were evaluated. Pregnant BALB/c mice were infected subcutaneously with 2 x 10(6) NC-1 tachyzoites on days 0, 7, or 14 of gestation. Dams from each group were sequentially killed during gestation and postpartum (PP). Pups were killed on days 1 and 7 PP. Infection on day 0 of gestation produced a high vertical transmission rate, although no changes in fetal mortality, stillbirth, and littermate size were observed. The highest level of vertical transmission, together with an increase in fetal mortality and stillbirth and a decrease in litter size, were observed when infection was done on day 7 of gestation. Finally, infection on day 14 of gestation produced the lowest vertical transmission. Furthermore, infection at any time during gestation compromised the postnatal development of pups, because neonates from infected dams showed less body weight and a delay in the hair development.

[Effects of acute and chronic Trypanosoma cruzi infection in pregnant mice]. / Efectos de la infección aguda y crónica por Trypanosoma cruzi en la gestación de los ratones.

Pathogens may impair reproduction in association or not with congenital infections. We have investigated the effect of acute infection with Trypanosoma cruzi, the protozoan agent of Chagas disease, on reproduction of female mice. In the acute, parasitemic, phase of the infection, female mice were totally unable to reproduce. Most of them (80%) were infertiles and did not develop any gestation. In the few gravid infected mice, implantation numbers were as in uninfected control mice. However, their fetuses presented a weight meanly reduced by 40% as compared to those of uninfected females, and all of them died during the gestation or whithin 48 h after birth. Such massive mortality did not result from congenital infection, which did not occur. The infertility and the fetal mortality occuring early in gestation (resorptions) were significantly correlated with a high maternal parasitemia, whereas later fetal mortality was associated with the presence of intracellular parasites in the utero-placental unit. The decidua was particularly receptive to T. cruzi multiplication, since this tissue harboured 125 fold more amastigotes than the maternal heart or other placental tissues. In addition, placentas of dead fetuses presented histopathological lesions (inflammatory infiltrates, fibrine deposits and ischemic necrosis). Such harmfull effects of acute infection were not observed when female mice were in the chronic phase of the infection, since these reproduce normally. Their fetuses only suffered from moderate and reversible growth retardation. These results indicate that, following the maternal parasite burden, T. cruzi infection may induce very deleterious effects on gestation.

Efectos de la infección aguda y crónica por Trypanosoma cruzi en la gestación de los ratones / Effects of acute and chronic Trypanosoma cruzi infection in pregnant mice

Pathogens may impair reproduction in association or not with congenital infections. We have investigated the effect of acute infection with Trypanosoma cruzi, the protozoan agent of Chagas disease, on reproduction of female mice. In the acute, parasitemic, phase of the infection, female mice were totally unable to reproduce. Most of them (80%) were infertiles and did not develop any gestation. In the few gravid infected mice, implantation numbers were as in uninfected control mice. However, their fetuses presented a weight meanly reduced by 40% as compared to those of uninfected females, and all of them died during the gestation or whithin 48 h after birth. Such massive mortality did not result from congenital infection, which did not occur. The infertility and the fetal mortality occuring early in gestation (resorptions) were significantly correlated with a high maternal parasitemia, whereas later fetal mortality was associated with the presence of intracellular parasites in the utero-placental unit. The decidua was particularly receptive to T. cruzi multiplication, since this tissue harboured 125 fold more amastigotes than the maternal heart or other placental tissues. In addition, placentas of dead fetuses presented histopathological lesions (inflammatory infiltrates, fibrine deposits and ischemic necrosis). Such harmfull effects of acute infection were not observed when female mice were in the chronic phase of the infection, since these reproduce normally. Their fetuses only suffered from moderate and reversible growth retardation. These results indicate that, following the maternal parasite burden, T. cruzi infection may induce very deleterious effects on gestation.

Placental pathology associated with fetal death in cattle inoculated with Neospora caninum by two different routes in early pregnancy.

Pregnant cattle were inoculated with N. caninum strain NC-1 tachyzoites intravenously (iv) (group 1, n = 8) or subcutaneously (sc) (group 2, n = 8) at 70 days' gestation. Control animals (group 3; n = 8) received uninfected Vero cells iv. Two animals from each group were killed at 14, 28, 42 and 56 days post-inoculation (dpi). Fetal mortality was 100% and 50%, respectively, in groups 1 and 2 from 28 dpi. In group 1 foci of degenerative fetal placental villi were observed at 14 dpi, with clusters of N. caninum tachyzoites in the affected mesenchyme. There was also inflammation of maternal septal tissues, with necrotic cell debris and serum exudate at the interstitium. At 28 dpi pregnancy had ended and the fetal cotyledons had become detached from the maternal caruncles. Immunohistochemically, particulate N. caninum antigen was detected in the cotyledons. At 42 and 56 dpi, fetal tissues had disappeared, the caruncles were greatly reduced in size, and the uterine epithelium had been largely restored. In group 2, lesions were either severe or absent ("all or nothing" response). In one animal carrying a dead fetus at 28 dpi, placentitis was much more severe than that seen in group 1 at 14 dpi. Lesions contained neutrophils, eosinophils and N. caninum antigen. In animals carrying dead fetuses at 42 and 56 dpi, fetal remains were found and the cotyledons contained N. caninum antigen. Antigen was also detected in fetal tissues. No significant pathological changes were detected in group 2 animals carrying live fetuses or any animal in group 3. Thus, N. caninum administered iv or sc in early pregnancy resulted in rapid fetal death, with parasite-associated lesions in the placenta and fetus. Of the two inoculation routes, the intravenous induced the more acute placental lesions and greater mortality.

Systemic and placental productions of tumor necrosis factor contribute to induce fetal mortality in mice acutely infected with Trypanosoma cruzi.

Blood levels and placental productions of IFN-gamma and TNF, known to be harmful for pregnancy, were determined in pregnant mice acutely infected with Trypanosoma cruzi and suffering massive fetal losses without congenital infection. INF-gamma was detected mainly at day 9 and TNF at days 17 and 19 of pregnancy in plasma of infected mice. TNF levels were significantly correlated to the percentages of dead fetuses. Placental cells produced TNF but not IFN-gamma, and addition of T. cruzi lysate to such cells strongly stimulated TNF production. Treatment of infected mice with pentoxifylline, known to decrease IFN-gamma production and to inhibit the TNF-alpha gene transcription, reduced the placental production of TNF, and the fetal mortality in comparison to control animals. Altogether these result suggest that TNF produced at systemic and placental levels plays a role in the fetal mortality induced in mice acutely infected with T. cruzi.

[Extra uterine pregnancy associated with a tubal schistosomiasis due to Schistosoma haematobium. A case report from Niger]. / Grossesse extra utérine et schistosomose tubaire due à Schistosoma haematobium. A propos d'un cas au Niger.

We are reporting the case of a 21-year-old woman hospitalized for pelvic pains in a context of secondary amenorrhoea, whose examinations revealed a tubal pregnancy After surgical operation, the examination of the operative part showed a schistosomal tubal obstruction. Schistosomal tubal obstructions are the cause of ectopic pregnancies and infertility not to be forgotten in endemic areas. The implementation of a control programme based on chemotherapy by praziquantel will enable the reduction of their frequency.

Isolation of Toxoplasma gondii from goats with history of reproductive disorders and the prevalence of Toxoplasma and chlamydial antibodies.

The prevalence of antibodies to Toxoplasma gondii and Chlamydia psittaci was assessed in goats with a history of abortion, stillbirth and neonatal mortality. Antibodies were detected in 540 (30%) and 57 (3.2%) goats out of 1799 tested by indirect haemagglutination and complement fixation tests, respectively. Toxoplasma gondii was isolated for the first time in Botswana from 22 out of 81 sets (27.2%) of foetal tissues, maternal and foetal cotyledons and uterine tissues of goats which had previously aborted or given birth to stillborn or weak kids that died within two days of birth. These results implicate T. gondii and C. psittaci, but especially the former, to be associated with caprine reproductive problems and require appropriate control measures.

Evaluation by different diagnostic techniques of bovine abortion associated with Neospora caninum in Spain.

Eighty foetuses from some of the main cattle-producing regions in Spain were analysed to investigate the participation of Neospora caninum in cases of bovine abortion. Diagnosis of the infection was determined by histopathological analysis complemented with immunohistochemistry, serology (IFAT and ELISA) and PCR tests. A total of 38.8% of the bovine foetuses analysed were considered to be infected by at least one of the diagnostic techniques used. Microscopic lesions consistent with Neospora infection in brain were identified in 31.3% of the samples, whereas only 10.7 and 15.3% were positive using serological and PCR analysis, respectively. Perfect agreement was shown between IFAT and ELISA, although there was little agreement among results of the other diagnostic techniques. Gestational age of aborted foetuses checked ranged from <3 to 9 months, with a mean of 5.9 months, and no difference in age was found between infected and non-infected foetuses (P>0.05). This study confirms the importance of N. caninum as a cause of abortion in Spain and underlines the need to use different diagnostic techniques to increase the chance to detect the infection in aborted foetuses.