Toxoplasma gondii
is a zoonotic protozoan of worldwide distribution. The present study provides information on risk factors affecting
T. gondii
infection in domestic and free-ranging wild ungulates ...sharing habitats in Mediterranean ecosystems in Spain. Serum samples from 482 extensively reared domestic ruminants and 2351 wild ungulates were tested for
T. gondii
antibodies using the modified agglutination test (MAT, cut-off 1:25).
Toxoplasma gondii
seroprevalence was 41.2% of 194 sheep, 18.6% of 199 cattle and 5.6% of 89 goats. The main risk factors associated with infection in livestock were the presence of cats, feeding on the ground and at stubble fields. In wild ungulates,
T. gondii
antibodies were detected in 10.5% of 1063 red deer, 15.6% of 294 fallow deer, 5.6% of 216 European mouflon, 5.6% of 90 Spanish ibex, 13.6% of 22 roe deer and 18.6% of 666 wild boars. The risk factors affecting
T. gondii
infection in wildlife were species, age and hunting season. Significantly higher seroprevalence was found in domestic ruminants, particularly in sheep, compared to the wild species tested. The present study indicates widespread exposure to
T. gondii
among domestic and wild ungulates in Southern Spain, with significant differences among species sharing the same ecosystem. The high seroprevalence observed in domestic ruminants, particularly in sheep, reinforces the need for farm management practices to control the risk factors associated with
T. gondii
infection in extensively reared livestock. Consumption of raw and undercooked food products from domestic and wildlife species may have important implications for public health.
In the present study, IFN-γ (Th1), IL-17A (Th17) and IL-4 (Th2) concentrations in response to concanavalin (ConA) and Neospora caninum antigen (Nc-1) stimulation were determined in cultures of cells ...from control uninfected (n=4), naturally N. caninum-infected (n=3) and experimentally N. caninum-infected (n=6) pregnant dams and their foetuses. Experimental animals were infected at 110days of gestation and euthanized 6weeks post-infection. In culture supernatants from the dams, significantly higher IFN-γ and IL-4 levels were found in the experimentally-infected animals compared to the control or naturally-infected dams. However, among the experimentally-infected dams no significant differences in IFN-γ production were observed regardless of the incidence of live or aborted/dead foetuses, though spleen cultures of dams carrying live foetuses showed the highest levels of IFN-γ. IL-17A production was very low and occasional in the dams infected with N. caninum and did not seem to be a major regulator of IFN-γ production in this model. Experimentally infected dams with live foetuses showed higher IL-4 levels and accordingly IFN-γ/IL-4 ratios were significantly lower than ratios recorded for cows with aborted/dead foetuses. In the infected foetuses of these dams, only spleen cultures showed high levels of IFN-γ and IL-4 after Nc-1 antigen and ConA stimulation, respectively. No IL-17A was detected in the foetuses. As conclusion, although we could not clearly relate a protective immune response against N. caninum abortion only to IFN-γ levels in cell cultures, our results highlight the important role of an inverse IFN-γ/IL-4 balance in conferring protection against abortion induced by this parasite.
•IFN-γ, IL-17A and IL-4 production in pregnant dams experimentally infected with Neospora caninum and in their foetuses.•Cytokine production compared in naturally infected and N. caninum experimentally infected dams, and in control pregnant dams.•Protective immunity against abortion could not definitively linked to IFN-γ levels in cell culture supernatants.•An important role was observed of an inverse IFN-γ/IL-4 balance in protecting against N. caninum abortion.
Abstract Antibodies to Toxoplasma gondii were determined in serum samples from 616 equids (454 horses, 80 mules and 82 donkeys) in a cross-sectional study of 420 herds in Andalusia (Southern Spain), ...the region with the highest number of equids in Spain. Antibodies to T. gondii were found in 10.8% horses, 15.0% mules and 25.6% donkeys by using the modified agglutination test (MAT) at a cut-off of 1:25. Herd seroprevalence for horses, mules and donkeys was 14.7% (48/327), 23.9% (11/46) and 34.0% (16/47), respectively, and 75 herds (17.8%) had at least one seropositive animal. Significant differences in T. gondii seroprevalence were observed among species, with donkeys having the highest seroprevalence and horses the lowest ( P = 0.04). Seroprevalence was significantly higher in herds with presence of domestic ruminants. This study is the first report of the presence of T. gondii antibodies in equine species in Spain and the first reporting T. gondii infection in donkeys in Europe. The presence of antibodies is indication of contact with the parasite and therefore, consumption of equine meat could be a potential source of human infection in Spain.
Wildlife and notably deer species – due to the increasing relevance of deer farming worldwide – may contribute to the maintenance of Coxiella burnetii, the causal agent of Q fever. Currently, there ...are no precedents linking exposure to deer species with human Q fever cases. However, a human case of Q fever was recently diagnosed in a red deer (Cervus elaphus) farm, which led us to investigate whether deer could be a source for environmental contamination with C. burnetii and ascertain the implication of C. burnetii in reproductive failure in the farm. Blood serum and vaginal swabs were collected from hinds either experiencing or not reproductive failure and tested to detect the presence of antibodies and DNA, respectively, of C. burnetii, Chlamydia abortus, Neospora caninum and Toxoplasma gondii. Serology and PCR results suggest C. burnetii was the primary cause of the reproductive failure. We identified vaginal shedding of C. burnetii in hinds, confirming red deer as a source of Q fever zoonotic infection.
Toxoplasma gondii infections are prevalent in many avian species and can cause mortality in some bird hosts. Although T. gondii has been isolated from various species of birds, the role of many ...different species of wild birds in the epidemiology of T. gondii remains unknown. Neospora caninum, a closely related parasite to T. gondii, has been recently confirmed to infect domestic chickens and wild birds such as house sparrows (Passer domesticus). The present study reports the presence of T. gondii and N. caninum DNA by PCR in brain tissues of 14 species of wild birds from Spain. From a total of 200 samples analyzed, 12 samples (6%) were positive for T. gondii 5 Eurasian jays (Garrulus glandarius), 5 magpies (Pica pica), 1 black kite (Milvus migrans) and 1 Griffon vulture (Gyps fulvus), while 3 samples (1.5%) were positive for N. caninum 2 magpies and 1 common buzzard (Buteo buteo). This is the first report of detection of T. gondii in magpies, griffon vulture and black kite and of N. caninum in common buzzard and magpies, extending the list of natural intermediate hosts for T. gondii and N. caninum infections to these species.
Wild felids are considered important in maintaining the sylvatic cycle of
Toxoplasma gondii. Although,
T. gondii antibodies have been reported in several species of wild felids, little is known of ...the epidemiology and risk factors associated with
T. gondii infection in wild cats. The Iberian lynx (
Lynx pardinus) is the most endangered felid species in the world. In the present study, seroprevalence and associated risk factors for
T. gondii infection in a large population of Iberian lynx in Spain were determined. Serum samples from 129 Iberian lynx collected from 2005 to 2009 and 85 wild rabbits (
Oryctolagus cuniculus), sharing the habitat with the Iberian lynx, were tested for antibodies to
T. gondii by the modified agglutination test (MAT) using a cut-off value of 1:25. Antibodies to
T. gondii were found in 81 of 129 (62.8%) Iberian lynx. Seroprevalence to
T. gondii in Iberian lynx significantly increased with age (
P
<
0.001).
T. gondii seroprevalences were similar in free-ranging (66.7% of 93) and wild-caught captive lynx (69% of 84) but significantly lower in captive-born lynx (22.5% of 40). Seroprevalence was higher in lynx with concurrent
Cytauxzoon
felis (88% of 25) but not with concurrent Feline Leukemia Virus (FeLV) infection (53.8% of 13)
. There were no significant differences in seroprevalence between sexes, geographic region and year of sample collection (2005–2009). Oocysts of
T. gondii were not detected microscopically in fecal samples from 58 lynx. Wild rabbits are considered the most important food for the lynx. Antibodies to
T. gondii were found in 14 (11.9%) of 85 rabbits tested. The present results indicate that
T. gondii infection is widespread in the two areas where Iberian lynx survive in Spain. The fact that four captive-born lynx seroconverted was indication of contact with
T. gondii also in the Captive Breeding Centers, hence, control measures to prevent
T. gondii infection would be necessary in these centers.
Toxoplasmosis is often fatal in captive wallabies, but the causes of this high susceptibility are not well understood. Here, we report fatal toxoplasmosis in a Bennet's wallaby (Macropus rufogriseus) ...due to an atypical Toxoplasma gondii strain for the first time in Europe. The wallaby was from a colony of 7 Bennet's wallabies that died over a 17-month period at a safari-zoological park in northeastern Spain. Only one of these wallabies was examined at necropsy. T. gondii-like organisms were detected by histological examination in several tissues and the diagnosis was confirmed through detection of T. gondii DNA by PCR. A nested PCR-based assay detected the 200- to 300-fold repetitive 529bp DNA fragment of T. gondii in a sample of brain tissue. Genotyping analysis with 15 single-copy microsatellite markers was performed on this positive DNA sample and revealed an atypical genotype. Atypical genotypes are frequently associated with severe forms of toxoplasmosis in humans. The present report highlights the possible implications of the introduction of new atypical, more pathogenic T. gondii strains, to non-endemic areas.
Neospora caninum is a major cause of abortion in cattle but it is not known why some infected animals suffer abortion while others do not. An essential role in protective immunity against N. caninum ...has been proposed for Th1 cytokines such as IFN-γ and IL-12 although cytokine patterns in N. caninum infected pregnant cattle have been scarcely addressed. In this study, gene expression of the cytokines IFN-γ, IL-12, IL-10, IL-4 and TNF-α was analyzed by real time RT-PCR in peripheral blood mononuclear cells in N. caninum naturally infected dams throughout pregnancy. Blood samples were drawn from 18 cows (13 N. caninum seropositive and 5 N. caninum seronegative) on Days 45, 90, 120, 150, 180 and 210 of pregnancy or until abortion. Four seropositive animals aborted. Compared to the seronegative animals, N. caninum infected dams showed up-regulated mRNA levels of the Th1 cytokines, IFN-γ, TNF-α and IL-12p40, along with up-regulation of the T regulatory (Treg) cytokine IL-10. In contrast, expression levels of IL-4 (Th2 cytokine) did not differ significantly among the different groups throughout the study period. Our findings indicate clear differences in peripheral blood cytokine gene expression levels during pregnancy between animals naturally infected with N. caninum and seronegative control animals. To the best of our knowledge, this is the first study to examine the gene expression of Th1, Th2 and regulatory cytokines in the peripheral blood of pregnant cows naturally infected with N. caninum.
Previous studies have shown that the use of beef bull semen significantly reduces the rate of abortions due to
Neospora caninum in artificially inseminated (AI) seropositive dairy cows. In addition, ...certain beef breeds could be more resistant to
N. caninum infection and abortion than others. The aim of the present study was to determine whether different crossbreed pregnancies, those derived from Limousin, Charolais, Piedmontese or Belgian Blue semen, carry different risks of abortion in
Neospora-infected dairy cows. The effects of possible interactions between maternal levels of
N. caninum antibodies and the different breed crosses were also evaluated. The study was performed on five commercial Holstein–Friesian dairy herds in Northeast Spain with previously confirmed diagnoses of
N. caninum infection in aborted foetuses. The study population was comprised of 1115 pregnancies: 633 pregnancies recorded after AI using Holstein–Friesian semen from 18 bulls and 482 after AI using beef semen from 27 bulls (304 inseminations using semen from Limousin bulls, 191 from Belgian Blue bulls, 89 from Piedmontese bulls and 49 from Charolais bulls). Abortion rates were 32.2% (155/482) and 15.2% (96/633) for seropositive cows inseminated with Holstein–Friesian and beef breed semen, respectively. Logistic regression analysis revealed the herd and the interaction between maternal
N. caninum antibody titre and the different crossbreeds as significant factors affecting the abortion rate. Lowest abortion rates, similar to that shown by seronegative animals in the analysed herds (3.2%, 239/7432), were observed in dams AI using Limousin semen that had low (<30 relative index (RI) units)
N. caninum antibody titres (2.1% abortion, 3/145) and these cows were used as reference. Compared to the cows used as reference, cows with low
N. caninum antibody titres (<30 RI units) showed a similar risk of abortion when inseminated with Piedmontese or Charolais bull semen, but higher risk of abortion when inseminated with Holstein (17.9 times) or Belgian Blue (7.2 times) bull semen. All cows with high
N. caninum antibody titres (≥30 RI units) had a higher risk of abortion, ranging from 8.9 times (cows inseminated with Limousine semen) to 37.8 times (cows inseminated with Piedmontese semen), compared to the cows used as reference. In conclusion, different crossbreed pregnancies carried different abortion risks in
Neospora-infected dairy cows. The use of beef bull semen dramatically reduced the risk of abortion in dairy cows, especially if Limousin breed semen was used. Moreover, this reduction was found to be dependent on the
N. caninum antibody titre such that the lowest incidence of abortions was recorded in Limousin semen inseminated cows with low antibody titres. Insemination of
Neospora-seropositive cows with beef bull semen could both reduce the risk of abortion and avoid breeding replacements for infected cattle.
Infection with Neospora caninum is the leading cause of abortion in cattle. In cows naturally infected with N caninum, plasma concentrations of pregnancy-associated glycoproteins (PAG) 1 and 2 ...indicate fetal-placental well-being, whereas an excess of progesterone in the second trimester of gestation has been related to high abortion rate. The immunosuppressive action of progesterone on the uterus during gestation has been attributed in part to the uterine serpins (SERPINA14). This study examines expression patterns of the genes SERPINA14, PAG, and PAG2 at the fetal-maternal interface in dairy heifers experimentally infected with N caninum during the second trimester of pregnancy, when most abortions takes place in natural conditions. Irrespective of infection, expression of SERPINA14 was higher, and expression of PAG1 and PAG2 lower, for intercaruncular endometrium than for caruncles or cotyledons. Cotyledonary tissues showed the highest expression of both PAG genes but lowest expression of SERPINA14. The expression of SERPINA14 was significantly higher in intercaruncular endometrium of control dams than for infected animals, pointing to potential disruption of modulation of maternal immune function during infection. Dramatically reduced SERPINA14 was particularly apparent in infected dams with aborted fetuses. There was also a negative association between N caninum antibody titers with SERPINA14 and PAG expression in infected animals, further suggesting that N caninum infection downregulates the uterine immunosuppressive function of SERPINA14.
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