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In a 500 head dairy sheep flock in Northern Greece, massive abortions (60%) were observed at 110-130 days of gestation. Attempts were made to treat the abortions with oxytetracyclin L.A. 20% but they were not successful. Toxoplasmosis was confirmed by laboratory examination of blood sera of ewes, aborted fetuses, and fetal brain samples. The remain...
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Toxoplasmosis is a zoonotic protozoan parasitic disease caused by Toxoplasma gondii. The aim of the present study was to determine the prevalence of T. gondii infection in sheep, goats and cattle in Chattogram division. In his study a total of 220 sera samples from different animals were collected from different herds of Chattogram division. Among...
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... Different cross-sectional studies, mainly serological ones, and case reports are available on T. gondii in both domestic and wild animals in Greece, namely in domestic swine and wild boars [38][39][40], sheep [41][42][43][44][45][46][47][48][49][50], goats [41][42][43][45][46][47][48]51], cattle [52][53][54], birds [55][56][57], hares [58], equines [59], cats [60][61][62], wildcats [63], and in one camel [64] (Table 1). Some of these animal species, i.e., cats, chickens, or even hares, can be used as sentinels for human infection in specific regions, and their seropositivity can prove helpful in assessing the environmental contamination with oocysts [7,14,57,60]. ...
... Toxoplasma gondii seroprevalence in Greek sheep has been extensively studied throughout the years [41][42][43][44][45][46][47][48][49][50]. Estimations ranged from 23% in Crete in 1995 [48] to 90% in Trikala in 2019 [44], with most studies finding seropositivity of around 50% and an upward trend throughout the years, as seen in Table 1. ...
... These seropositivity rates are similar to the global pooled seropositivity of T. gondii in abortive sheep calculated at 56% [34]. In one case report, 60% of pregnant ewes aborted, and T. gondii was diagnosed as the causative agent [50]. However, other studies demonstrated no association between T. gondii seroprevalence and abortions in ewes [41,43]. ...
Toxoplasma gondii is a zoonotic protozoon with a complex life cycle and the second most important foodborne pathogen in Europe. Surveillance of toxoplasmosis is based on national considerations since there are no mandatory controls along the food chain in the European Union, and underreporting of meat is still a problem in many countries like Greece. The current review provides an overview of T. gondii prevalence, associated risk factors, and surveillance in animals in Greece, focusing on the transmission role of meat and highlighting the control measures that should be adopted by consumers. Sows, wild boars, hares, equines, and cats had lower, while sheep and goats generally had higher seroprevalence than their respective pooled European and global values. Seroprevalence in chickens was similar between Greece and Europe, while there was high variation in cattle studies, with no data regarding dairy products. Though a comprehensive meat safety assurance system is the most effective approach to control the principal biological hazards associated with meat, such as T. gondii, the prerequisite risk categorisation of farms and abattoirs based on EFSA’s proposed harmonised epidemiological indicators has not materialised as yet in Greece. Therefore, comprehensive control strategies are still required to ensure food safety and safeguard public health.
... T. gondii is the second most common cause of abortions in sheep in the UK [65], and was the abortifacient most commonly detected in both ovine (18.1%) and caprine (13%) fetuses in Sardinia, Italy [62]. This protozoon was responsible for a massive outbreak of abortions (60%) in a Greek dairy sheep flock [71]. Rates of T. gondii-specific DNA detected in ovine-abortion derived tissues submitted for diagnosis were 10% in Ireland and 4.5% in Germany [63,72]. ...
Coxiella burnetii is an intracellular bacterium causing human Q fever and reproductive disorders in domestic ruminants. We analyzed the occurrence of C. burnetii and co-infections with six other major pathogens causing abortion in sheep (1242 cases) and goat (371 cases) flocks from Spain and Portugal. After real-time PCR detection, co-infections were established by principal component and cluster analysis that grouped cases based on the joint presence/absence of several microorganisms. C. burnetii and Chlamydia abortus were the most common abortifacient agents with approximately 75% of cases from both hosts testing positive, followed by Toxoplasma gondii, Campylobacter sp., Salmonella enterica, border disease virus and Neospora caninum. C. burnetii was significantly more common than C. abortus in goat abortions (p < 0.001). Co-infections with at least two pathogens were found in more than 66% cases of ovine abortions and 36% cases of caprine abortions testing positive for C. burnetii, mostly including mixed infections with only C. abortus. These findings indicate that both pathogens are the most significant ones to be readily prevented by vaccination in this geographical area. Biosecurity and biocontainment measures are also steadfastly recommended to prevent both the economic losses and public health risks associated with most of these abortifacient agents.
... The infrequent vaccination against contagious ecthyma is the consequence of the requirement for a specific import licence on a farm-by-farm basis, in accord with the incidence of the infection in the farms. Finally, despite the presence of T. gondii infections in small ruminants in Greece and the widespread cases of abortions caused by this pathogen [38,39], also with zoonotic implication [40], issues in the marketing of the relevant commercial product have likely impeded the use of the vaccine in the farms. ...
This paper reports findings regarding patterns of vaccine usage in sheep and goat farms, in 325 sheep flocks and 119 goat herds throughout Greece. The objectives of the study were (a) to describe the patterns of vaccine administration in small ruminant farms and (b) to highlight factors that were associated with vaccinations in the farms. Vaccination against brucellosis was performed in all farms into the study. Among optional vaccinations, anti-clostridial vaccination was most frequently performed (in 97.8% of farms), followed by vaccination against contagious agalactia, (56.5% of farms), pneumonia (41.2%), chlamydial abortion (38.1%), staphylococcal mastitis (36.0%), and paratuberculosis (9.5%). Vaccinations against pneumonia and staphylococcal mastitis were performed more frequently in sheep flocks, whilst vaccinations against paratuberculosis were performed more frequently in goat herds. On average, 2.8 and 2.7 optional vaccinations (i.e., additionally to vaccination against brucellosis) were performed in sheep and goat farms, respectively. The increased number of vaccines administered was associated with a higher average milk production in the respective farms. There was an association of vaccination against staphylococcal mastitis with a reduced recovery of staphylococci from the bulk-tank raw milk. In multivariable analyses, significant associations of the administration of the various optional vaccines were seen with 15 variables, 11 related to health management practices and 4 related to the demographic characteristics of farmers; the collaboration with a veterinarian, the daily number of milking sessions, and the period spent daily by the farmer at the farm premises were each associated with the administration of vaccines against three infections.
... 53 Tedavi öncesinde %60 oranında abortusların görüldüğü bir koyun sürüsünde sülfadimidin iki farklı dozda İM olarak 48 saat ara ile 4 kez uygulanmış abortus oranının 20 mg/kg'lık dozda %25'e, 33mg/kg dozda ise %7'ye düştüğü tespit edilmiştir. 54 Keçilerde de dekokuinat ve monensin'in koyunlardakine benzer şekilde uygulanmasının faydalı olabileceği belirtilmektedir. 41 Neosprosis'de ise triazinon grubu ilaçların yeni doğan enfekte buzağı ve kuzularda humoral immün yanıtı modüle ettiği, klinik semptomları ve doku kistlerini azalttığı bildirilmiştir. ...
Toxoplasmosis ve neosporosis küçük ruminantlarda abortuslara ve ekonomik kayıplara neden olmaktadır. Günümüzde Toxoplasma gondii ve Neospora caninum konusunda yapılan çok sayıda çalışmaya
rağmen hâlâ elimizde istenilen düzeyde etkin bir ilaç ve dünya genelinde yaygın bir aşı bulunmamaktadır. Her iki hastalığın epidemiyolojik özellikleri tam olarak anlaşılmadığından dolayı kontrol ve eradikasyona yönelik bilgilerimiz ise yeterli değildir. Bu bölümde koyun ve keçilerde toxoplasmosis ve
neosporosis konusunda toplu ve güncel bilgilerin sunulması hedeflenmiştir.
... 53 Tedavi öncesinde %60 oranında abortusların görüldüğü bir koyun sürüsünde sülfadimidin iki farklı dozda İM olarak 48 saat ara ile 4 kez uygulanmış abortus oranının 20 mg/kg'lık dozda %25'e, 33 mg/kg dozda ise %7'ye düştüğü tespit edilmiştir. 54 Keçilerde de dekokuinat ve monensin'in koyunlardakine benzer şekilde uygulanmasının faydalı olabileceği belirtilmektedir. 41 Neosprosis'de ise triazinon grubu ilaçların yeni doğan enfekte buzağı ve kuzularda humoral immün yanıtı modüle ettiği, klinik semptomları ve doku kistlerini azalttığı bildirilmiştir. ...
Toxoplasmosis and neosporosis cause abortions and economic losses in small ruminants.
Today, despite a lot of studies on Toxoplasma gondii and Neospora caninum, we still do not have a drug
producing the desired effect and a vaccine used worldwide. Since the epidemiological features of both
diseases are not fully understood, our knowledge on control and eradication is insufficient. In this section, it is aimed to present collective and up-to-date information on toxoplasmosis and neosporosis in
sheep and goats.
... All the above examinations were found negative. Abortion of the camel was related to toxoplasmosis infection, based on the positive fetus direct smear results, PCR and the mother's antibody titer, therefore toxoplasmosis treat-Available at: http://ijpa.tums.ac.ir ment, already applied in small ruminants, with sulphadimidine (Sulfadimidine ® -CEVA) at a dose of 33 mg/kg (14,15), immediately initiated. The camel responded quickly to treatment since 24 h after the first treatment the animal started to eat. ...
... In described spontaneous and experimental cases of toxoplasmosis in small ruminants (14,19,20) the affected animals usually have fever and inappetence, some hours before the abortion, but these signs resolve without medical treatment after abortion. In the present case, the camel was probably bought pregnant about 12 months ago, since there were no other camels in the farm and gestation period in camels lasts 15 months, and the owner was unaware of the animal's pregnancy. ...
A female, 5 yr old Bactrian camel was presented to the Exotic and Wildlife Medicine Unit, School of Veterinary Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece, with severe dehydration, depression, anorexia, mild dyspnea and diarrhea. Supportive treatment immediately initiated with fluids, electrolytes and broad-spectrum antibiotics. The general condition of the animal was stable for the next 3 days, but at 4th day became worse, since the camel remained in sternal recumbency, denied to drink water and abortion of a mummified fetus was noticed. The aborted fetus and fetal membranes were submitted for laboratory examinations (bacterial cultures, MZN, cytology, PCR) that revealed Toxoplasma gondii infection. Treatment with sulfadimidine improved the situation of the animal that returned to its farm 1 week later. This seems to be the first reported case in the literature of confirmed toxoplasmic abortion in camels.
... Edwards and Dubey (2013) reported toxoplasmosis in a small sheep flock (n = 41) in Texas where 31 (75%) lost some or all of their lambs. Similarly, Giadinis et al. (2011) reported a 60% abortion rate in a large dairy sheep flock (n = 500) in Greece, and Gabardo (2013) reported a 40% abortion rate in a small meat-sheep flock (n = 250) in Brazil. ...
This study estimates the economic losses due to outbreaks of toxoplasma abortions in a dairy (1928 sheep) and a meat (700 sheep) flock in Spain raised under intensive and semi-extensive management conditions, respectively. In both flocks, sheep were divided into multiple groups to synchronise reproduction. The outbreaks resulted in abortion rates in individual lots of 12.6% (30/239) in the dairy flock and 33.3% (70/210) in the meat flock. Toxoplasma gondii was definitively diagnosed in most submitted cases and the only abortifacient pathogen identified despite extensive investigation. Upon completion of lambing and lactation, veterinarians and farmers completed a questionnaire to gather the data to determine the direct economic impact. The calculated total direct economic losses were €5154.5 (€171.8/abortion) in the dairy flock and €4456 (€63.6/abortion) in the meat flock. Results suggest that flock size, production system, abortion rate and control measures are the key factors influencing economic losses, which vary greatly between individual flocks.
... Therefore, our first goal was to investigate the effect of the protozoan T. gondii on mature ram sperm quality after the experimental infection of premature males since there are no such data in the literature. Moreover, the treatment of toxoplasmosis in ewes involves the administration of monensin [22], sulphadimidine [23,24], or sulphamezathine and pyrimethamine in combination [25]. Since there are no reports about the effect of sulphadimidine administration on T. gondii contaminated rams, the second goal of the present study was to explore the possible efficacy of sulphadimidine treatment in T. gondii experimentally infected premature rams. ...
... The administration of sulphadimidine has been reported to reduce the abortion rate in naturally infected sheep and goat flocks [23,24]. It has also been reported that following toltrazuril treatment, the decrease of seropositivity rates in lambs indicates a significant reduction of new tissue cyst formation [30]. ...
... Research data indicate the beneficial effect on infected female sheep of monensin [22] or sulphadimidine administration [23,24]. A similar beneficial effect is also reported for the administration of sulphamezathine and pyrimethamine [25]. ...
The aim of this study was to investigate the effect of experimental Toxoplasma gondii infection on ram sperm quality. Five months old, pre-pubertal, rams were divided into four groups (n = 8 per group). Group A was the control group; the remaining animals received per os (p.o.) 5000 oocysts per ram. Group B did not receive treatment post-infection (p.i.). Group C received sulphadimidine (intermuscular injection (i.m.) 33 mg/kg for eight days; every 48 h) two months p.i. and Group D received the same drug twice (24 h p.i. and two months later). Blood samples were collected every 15 days to detect serum immunoglobulin G (IgG). Epididymal sperm samples were analyzed for concentration, kinetics, morphology/viability, functional membrane integrity, DNA integrity, and the presence of parasite DNA. Histopathological examination was performed on the testes. The IgG titres in infected groups raised two weeks p.i. and remained high for four months. Higher values were noticed in viability and functional membrane integrity in positive spermatozoa in the control group compared to other groups, level of significance p < 0.05. Abnormal sperm was higher in groups C and D vs. A and C vs. B (p < 0.05). T. gondii DNA was detected in three sperm samples of the infected rams (12.5%). Histopathology revealed similar findings with little variation among all infected groups, characterized mostly by increased interstitial connective tissue, non-purulent inflammation, and presence of seminiferous tubules with spermatogenic cell depletion, which increased gradually from D to C and B groups. In conclusion Toxoplasmosis in pre-pubertal age negatively affected mature ram sperm quality, while sulphadimidine administration failed to alter this.
... Midgestation infections usually result in the birth of a stillborn or weak lamb, while infection in later gestation may result in the birth of a live, clinically healthy, but infected lamb [13]. According to another study, massive abortion occurs at 110-130 days of gestation [27]. e frequency of T. gondii infection in the age group ≥120 days was higher than other age groups of aborted fetuses. ...
Toxoplasma gondii is a zoonotic obligate intracellular protozoan parasite that infects warm-blooded animals as well as humans worldwide. The purpose of this study was to delineate the prevalence of Toxoplasma infection in aborted fetuses of sheep in North Khorasan province, Iran. Three hundred and ninety-nine samples of the liver (133 samples), placenta (133 samples), and brain (133 samples) from 133 aborted fetuses of sheep were collected from 2015 to 2017. The ages of aborted fetuses were higher than 120 days’ gestational age in this study. According to the samples, sixteen out of 133 aborted fetuses of sheep were infected with T. gondii. Toxoplasma DNA was found in the placenta (68.75%) and liver (31.25%) samples of infected fetuses using the PCR method. The highest and lowest rates of Toxoplasma infection were observed during 2016 and 2017, respectively. Shirvan and Faruj provinces were recognized as the two most infected districts among others. There was a significant difference between the year and abortion rate in sheep due to infection by the Toxoplasma parasite (P0.05) in different areas. According to the present study, T. gondii infection can be one of the causes of fetus abortion of sheep in North Khorasan province, Iran.
... Neospora caninum and Toxoplasma gondii are closely related cyst-forming apicomplexan parasites identified as important causes of reproductive failure in cattle [13,14]. Abortion cases attributed to N. caninum [12,21,35] and T. gondii [10,20,28,44] infection have been occasionally reported in sheep. These parasites have already been identified in 77% of 74 brain samples from aborted sheep fetuses [23]. ...
Background: Neospora caninum and Toxoplasma gondii are closely related cyst-forming apicomplexan parasites identified as important causes of reproductive failure in cattle. Moreover, abortion cases attributed to N. caninum and T. gondii infection have been occasionally reported in sheep. Due to the relatively scarce information on the molecular detection of N. caninum in the semen of naturally infected rams, this study aimed to detect parasitic DNA in fresh semen samples and in frozen extended semen straws from male sheep from artificial inseminations centers in Southern Brazil.Materials, Methods & Results: Semen samples of 38 rams from artificial insemination centers were evaluated. Eleven rams were naturally infected (seropositive for anti-N. caninum and/or anti-T. gondii IgG) and were selected for fresh semen collection. We tested all the samples for the closely related protozoan T. gondii to detect a possible cross-reaction and co-infection, due to the close similarity with N. caninum. The indirect fluorescent antibody test was used to detect IgG antibodies in the 11 serum samples from rams. Fresh semen samples were collected from 11 rams on days 1, 50, 55, and 58 using an artificial vagina and ewe in estrus. Other 27 rams had their frozen extended semen straws analyzed. A total of 20 fresh semen samples and 27 frozen extended semen straws samples were used to detect the presence of N. caninum and T. gondii DNA by polymerase chain reaction (PCR). Nc-5 and B1 genes were used as target regions to detect N. caninum and T. gondii DNA, respectively. The presence of N. caninum DNA was confirmed in the third collection of a fresh semen sample of one seropositive ram. T. gondii DNA was detected in a fresh semen sample of one seropositive ram. The DNA sequences of 186 bp from N. caninum (GenBank accession: MH806393) and 492 bp from T. gondii (GenBank accession: MH793503) were obtained by sequencing, and analysis revealed 99% and 100% identity, respectively, compared with other sequences deposited at GenBank. N. caninum and T. gondii DNAs were not detected in any of the 27 frozen extended semen straws used for artificial insemination.Discussion: This study demonstrated the presence of N. caninum and T. gondii DNA in fresh semen samples of naturally infected rams. The non-detection of N. caninum and T. gondii DNA in frozen semen samples of rams could be due to the dilution that was used to prepare the semen straws (GGL diluent and 5% glycerol), since fresh semen samples were not diluted prior to the test. Moreover, in our study, the volume of frozen semen samples (0.25 mL) used for PCR was lower than the volume of sediment obtained from fresh semen (0.5 mL), and the fresh semen centrifugation to obtain the sediment may have grouped the tachyzoites, increasing the sensitivity of the technique employed. No high IgG serological titers were detected in the rams at the time they were eliminating the parasite through fresh semen. The final titer of anti-N. caninum and anti-T. gondii IgGs in serum was 1:100, suggesting chronic infection. It is suggested that a new parasite elimination pathway is occurring among rams used for reproduction, due to the presence of N. caninum and T. gondii DNA in fresh semen samples from seropositive animals. Although the detection of genomic DNA of N. caninum and T. gondii in semen does not necessarily imply the presence of infectious stages of the parasites and does not determine their viability, these results demonstrate the need for further studies. Our study also indicates the need to reinforce preventive measures for sheep in artificial insemination centers until the risks are evaluated, by performing serological examinations with anti-N. caninum and anti-T. gondii antibodies, for instance, to select the rams that will be used for breeding.
