Visceral infection by Porocephalus spp. (Pentastomida) in Neotropical wild mammals.

Larval stages of pentastomids were collected from different organs of small mammals from the Peruvian Amazon. These parasitized mammals included: a western Amazonian oryzomys (Hylaeamys perenensis), an elegant oryzomys (Euryoryzomys nitidus), a lowland paca (Cuniculus paca), two kinkajous (Potos flavus), two silvery woolly monkeys (Lagothrix poeppigii) and a brown-mantled tamarin (Leontocebus fuscicollis). Pentastomids were found in the mesentery and parenchyma of the liver and lungs of these animals. All pentastomids were morphologically identified as nymphs of Porocephalus spp. Only the nymphs collected from select animals (the western Amazonian oryzomys, the elegant oryzomys and the brown-mantled tamarin) were analysed molecularly. Molecular analysis was performed amplifying the mitochondrial cytochrome c oxidase subunit I gene from select nymphs collected from the western Amazonian oryzomys, the elegant oryzomys and the brown-mantled tamarin. The nucleotide sequences exhibited 95.8-97.7% similarity between them. Also, these sequences showed an identity of 95.8-97.9% to Porocephalus crotali (GenBank accession numbers MG559647-MG559655). Molecular analysis indicated the presence of at least two Porocephalus species. These findings represent the first record of Porocephalus in these mammals, thus adding new intermediate hosts for this pentastomid genus. This work represents the first molecular data of Porocephalus in a Neotropical climate.

A comparison of Taenia solium and Taenia hydatigena infection in pigs using serological diagnosis and post-mortem inspection methods in Benoué division, North Cameroon.

The metacestodes of Taenia solium and Taenia hydatigena are the cause of cysticercosis in pigs. T. solium is also responsible of the taeniosis/neurocysticercosis complex in humans, constituting a main cause of epilepsy cases across endemic countries. T. hydatigena is non-zoonotic, but its occurrence in pigs contributes significantly to false positive reactions should genus-species serological methods be used for diagnosis of T. solium porcine cysticercosis. T. hydatigena is often considered not common in pigs in Africa compared to T. solium. On the basis of the evidence that these two cestodes coexist in Cameroon, we examined the viscera of 305 pigs for the identification of the metacestodes of T. hydatigena in Bénoué division, North Region of Cameroon. Tongue, masticatory muscles and heart were sliced for the identification of T. solium cysticerci (TMH dissection test). Twenty seven (8.85%) and 16 (5.24%) pigs were found infected with the metacestodes of T. solium and T. hydatigena, respectively. The difference between the two rates of infection was not statistically significant (P > 0.05). Serum samples were also collected for the evaluation of an inhibition ELISA (i-ELISA) specific to antibodies anti- T. solium or anti-T. hydatigena cysticerci. After incubation of these sera with cyst fluid of T. solium, T. hydatigena, T. multiceps multiceps, T. multiceps gaigeri and T. saginata to eliminate cross-reactions among cestodes parasites, the i-ELISA indicated that 26.56% and 28.52% slaughtered pigs had predominant specific antibodies to cyst fluid of T. solium and T. hydatigena, respectively. Combination of TMH dissection test, i-ELISA and a standard indirect ELISA in a Bayesian simulation approach revealed a true prevalence of 19.27% (0.7-49.27, CI 95%) and 24.85% (5.17-48.34, CI 95%) of porcine cysticercosis due to T. solium and T. hydatigena, respectively. These results indicated that T. hydatigena is as prevalent as T. solium in pigs in the North of Cameroon.

Larva Migrans of Baylisascaris potosis In Experimental Animals.

Occurrence of clinical signs by infection with Baylisascaris potosis, the roundworm of kinkajous ( Potos flavus), in mice, rats, and rabbit were studied, and the migration behavior of larvae in mice were compared with that of Baylisascaris transfuga, the roundworm of bears ( Ursus spp.). Three groups of 8 mice, 3 groups of 6 rats, and 3 groups of 2 rabbits were inoculated with either 10, 100, or 1,000 B. potosis eggs. The other 8 mice were inoculated with 1,000 B. transfuga eggs. Animals were monitored for the occurrence of clinical signs until 60 days postinoculation (DPI). The carcass, viscera, brain, and eyes of each of 6 mice inoculated with 1,000 eggs of B. potosis or B. transfuga at 60 DPI were removed individually, and the number of larvae was counted. One mouse inoculated with 100 B. potosis eggs showed rolling at 27 DPI, and 1 larva was found in the medulla oblongata of this mouse. No clinical signs were observed in the other mice or in the rats and rabbits. A mean of 387.2 larvae was recovered from mice inoculated with 1,000 B. potosis eggs, and a mean of 422.0 larvae from mice inoculated with 1,000 B. transfuga eggs. The highest number of larvae was recovered from the carcasses for both B. potosis and B. transfuga. In the viscera, higher numbers of B. transfuga larvae (mean 131.8) were seen than B. potosis larvae (mean 33.1). In the brain, only 1 larva was detected in 1/6 mice inoculated with 1,000 B. potosis eggs, whereas a mean of 21 larvae was detected in mice inoculated with 1,000 B. transfuga eggs. A few larvae (range 0-1) were detected in the eyes of both mice inoculated with B. potosis or B. transfuga eggs. The result indicated that B. potosis larvae do not show a higher tendency to migrate into the brain of mice than B. transfuga larvae. However, 1 mouse inoculated with 100 eggs had 1 larva in the central nervous system and showed a serious neurological sign. This result may underline a potential risk of B. potosis to cause neural larva migrans in humans.

Light and Scanning Electron Microscopic Studies of Unionicola tetrafurcatus (Acari: Unionicolidae) Infecting Four Freshwater Bivalve Species and Histopathological Effect On Its Hosts.

Water mites of the genus Unionicola are the most common symbionts of freshwater bivalves. During the current investigation, a total of 120 live freshwater mussels representing 5 species, Corbicula fluminea (Veneroida), Coelatura aegyptiaca (Unionoidea), Mutela rostrata, and Chambardia rubens (Mutelidae), were collected from 2 localities in Tura (Helwan Governorate) and El Kanater (Qaluobiya Governorate), Egypt. Only 3 of the 4 bivalve species listed are considered freshwater bivalves (members of Unionoidea). Corbicula fluminea belong to the family Cyrenidae within Veneroida. Collected mussels were dissected and examined for the presence of unionicolid mites. It was found that 30.83% (37/120) were infected with a single mite species, Unionicola tetrafurcatus (Unionicolidae). The highest prevalence was observed during the summer with 83.33% (25/30) whereas the least was observed in autumn, i.e., 33.33% (10/30). Mites were recovered from the gills, gonads, and visceral mass of mussel hosts. Gills of host mussels were the primary site of oviposition for Unionicola mites. Smaller bivalves in size had significantly greater numbers of mites than did larger ones in size. Numbers of mites per host species was variable and the highest prevalence level of 83.33% (25/30) was recorded in Cor. fluminea while the lowest one of 16.66% (5/30) was found in Ch. rubens. Morphological and morphometric characterizations of mites revealed some differences between the present species and other related Unionicola. Histopathological responses of host mussels to the eggs, larvae, and cuticular remnants of U. tetrafurcatus were also studied. Therefore, the present study demonstrated that freshwater bivalves have a new host and locality records for infection with U. tetrafurcatus. Future studies are recommended to include advanced molecular characteristics for these mites.

Cystic Echinococcosis in Turkana, Kenya: The Role of Cross-Sectional Screening Surveys in Assessing the Prevalence of Human Infection.

Cystic echinococcosis (CE) is a neglected zoonotic disease caused by Echinococcus granulosus. Infection leads to formation of cysts within the viscera of the human host. In the 1980s, the transhumant population of northwest Turkana, Kenya, was found to have the highest prevalence of CE in the world. In 1983, AMREF Health Africa and the Kenya Medical and Research Institute launched a CE Control Program in northwest Turkana, screening and treating the local people. This epidemiological study of CE in Turkana analyses approximately 30 years of surveillance and surgical data. Cyst data were categorized using the World Health Organization CE ultrasound classification system before being analyzed for cyst, patient, and population characteristics, and surveillance data from 1985 are compared with more recent surveillance data to assess changes in prevalence in the control region since the commencement of control activities. In 1985, the prevalence of CE among the Turkana was 5.6%. In 2010-2011 and 2011-2012, calculated CE prevalence rates were 1.9% and 3.8%, respectively. Since the 1980s, the age distribution of people with CE in Turkana has shifted: initially, cases of CE appeared predominantly within younger age groups, but recent data reveal a higher prevalence within older age groups. The frequency of infection in females also significantly decreased. The reduction in CE prevalence from 5.6% in the 1980s to 1.9-3.8% in 2010-2012 and the shift in age distribution of CE-infected individuals over time indicate that the prevalence of CE in Turkana has decreased since the control program began.

Transfer of CD11c+ lamina propria mononuclear phagocytes from post-infectious irritable bowel syndrome causes mucosal barrier dysfunction and visceral hypersensitivity in recipient mice.

The role of low-grade inflammation in the development of post­infectious irritable bowel syndrome (PI­IBS) has attracted increasing attention. Abnormal CD11c+ mononuclear phagocytes, such as dendritic cells (DCs), macrophages, and monocytes, are involved in the disruption of immune tolerance in organisms, which can lead to the development of chronic inflammatory diseases. The present study tested the hypothesis that CD11c+ lamina propria mononuclear phagocytes (CD11c+ LPMPs) contribute to increased mucosal permeability and visceral hypersensitivity in a PI­IBS mouse model. CD11c+ LPMPs were isolated and purified via the digestion of intestinal tissues and magnetic­activated cell sorting. We detected increased mucosal permeability, visceral hypersensitivity and intestinal inflammation during both the acute and chronic stages of Trichinella infection. Following the transfer of CD11c+ LPMPs from PI­IBS mice into normal mice, low­grade inflammation was detected, as demonstrated by increased IL­4 expression in the ileum, as well as enhanced mucosal permeability, as indicated by decreased transepithelial electrical resistance and the pre-sence of ultrastructural alterations. More importantly, the mice that underwent adoptive transfer of CD11c+ LPMPs from the PI­IBS mice also exhibited increased abdominal withdrawal reflex scores and a decreased threshold. Our data demonstrated that the CD11c+ LPMPs from this PI­IBS mouse model were not only able to transfer enteric inflammation to the normal mice but also caused abnormal intestinal function, characterized by epithelial barrier disruption and visceral hyperalgesia.

Visceral larvae as a predictive index of the overall level of fish batch infection in European anchovies (Engraulis encrasicolus): A rapid procedure for Food Business Operators to assess marketability.

The European anchovy (Engraulis encrasicolus), one of the most important pelagic fish resources in the Mediterranean Sea, is frequently infected by anisakid larvae. Food Business Operators (FBOs) should use appropriate sampling plans and analytical methods to avoid commercialization of massively infected batches and reduce the risk of transmission of viable zoonotic larvae. In this study, performed at FishLab (Department of Veterinary Sciences of the University of Pisa) during 2016, an official sampling plan was associated with a digestion protocol for the inspection of anchovies. Considering that anisakid larvae are usually located in the fish visceral cavity and in the adjacent muscles (VM), this part was analyzed. In particular, we assessed the reliability of the digestion of a subsample of 150g (±30g) of VM, randomly collected from 29 specimens, in estimating the marketability of the anchovies' batch. Fifty-seven samples of 29 anchovies were collected. Each anchovy was sectioned to separate VM. All the subsamples were digested, and visible larvae counted. A high correlation between the number of larvae in VM regions and in the total batch was observed, indicating a very significant contribution of the VM region on total number of parasites. The Mean Abundance (MA) was used to assess the batch marketability according to a threshold calculated on the basis of the maximum number of nematodes tolerated per sample. Considering that the MA can be calculated only when the number of examined specimens is known, the number of visible Larvae per gram of tissue (LpG) was calculated on 150g (±30g) of VM subsamples. A LpG marketability threshold was calculated dividing the maximum number of tolerated nematodes by the average weight of a sample of 29 anchovies calculated considering data available in literature. To evaluate the diagnostic performance of the LpG threshold, the marketability of 57 batches assessed on the basis of the MA threshold was assumed as the gold standard. The proposed LpG showed very high Specificity and Sensitivity. These findings suggest that the analysis of VM is representative of the overall infestation of the batch, both when considering the absolute number of parasites and the LpG, and may represent a valid alternative to the whole anchovy digestion. In particular, the use of an automated digestive method, coupled with the aforesaid sampling plan, could allow the procedure to be used by FBOs in operational conditions.

ZOONOTIC ENCOUNTERS AT THE SLAUGHTERHOUSE: PATHWAYS AND POSSIBILITIES FOR THE CONTROL OF CYSTIC ECHINOCOCCOSIS IN NORTHERN MOROCCO.

This study traces the biosocial dynamics of Echinococcus granulosus - a zoonotic tapeworm spread between dogs, livestock and people - at slaughterhouses in Morocco. One of the most important parasitic zoonoses worldwide, this neglected cestode is responsible for a debilitating, potentially life-threatening, human disease and significant livestock production losses. Transmission can be interrupted, among other ways, by restricting dogs from eating cyst-infected livestock viscera. Recent epidemiological studies in Sidi Kacem province, northern Morocco, found that government-operated slaughterhouses were 'hotspots' for hydatid cysts in livestock and infection in dogs. An ethnographic approach was used to compliment these studies, exploring 'how' and 'why' cysts were being openly discarded. All seven visited slaughterhouses had low levels of hygiene, oversight and infrastructure. This was described locally as perpetuating a sense of 'chaos' that normalized (un)hygienic practices and justified the ignoring of state rules and regulations. However deference to 'poor' infrastructure, both physically and symbolically, served to under-emphasize local institutional logics, which were mediated by prevailing risk perceptions, economic practices and local socio-political norms. These included inter-departmental government relationships, the motivation of veterinary technicians, the political lobbying of butchers and market-based mitigation strategies. The study shows the importance of understanding E. granulosus from a biosocial perspective, and the need for more long-term, participatory and integrated 'One Health' approaches for neglected zoonotic diseases.

Human pentastomiasis in Sub-Saharan Africa.

Pentastomiasis is a rare zoonotic infection but it is frequently observed in Africa and Asia. Most human infections are caused by members of the Armillifer armillatus species. They are responsible for visceral pentastomiasis in Western and Central Africa. Humans may be infected by eating infected undercooked snake meat or by direct contact with an infected reptile. An increasing number of infections are being reported in Congo, Nigeria, and Cameroon. Despite an occasionally high number of nymphs observed in human viscera, most infections are asymptomatic and often diagnosed by accident during surgery or autopsy. The clinical presentation of pentastomiasis is quite varied and depends on infected tissues. The liver, lungs, and pleura are most frequently involved. Abdominal emergencies have been reported. Diagnostic delays always occur and diagnosis focuses on the patient's lifestyle and living environment. It is mainly based on the morphological description of the parasite's calcified cuticle, the site of the lesion, and the parasite's region of origin. Most patients do not require any treatment. Personal measures such as avoidance of contact with snake droppings are recommended to prevent transmission. Imported pentastomiasis has been observed in African migrants.

Survey for Toxoplasma gondii by PCR detection in meat for human consumption in Colombia.

The overall risk for toxoplasmosis in meat produced in Colombia is unknown. We analyzed by PCR assay meat samples for human consumption in two types of plants in Colombia: 120 samples from class I plants (60 samples from chicken, 30 from swine and 30 from beef) and 60 from class II plants (30 samples from beef and 30 from swine). Presence of Toxoplasma DNA was established by targeted B1 nested PCR assay. We detected 79 (43%) samples that were positive by B1 nested PCR (33 from chicken, 22 from beef, and 24 from pork). No differences were found by region or species. Eleven positive samples were confirmed by sequencing of the B1 repeated region. Some polymorphisms were detected without relation with clonal groups nor meat species. Food animals are highly exposed to Toxoplasma in Colombia. Detailed studies are needed to establish the reasons for differences in Toxoplasma prevalence between farms, regarding practices of animal food production.

Comparative study of viscerotropic pathogenicity of Leishmania major amastigotes and promastigotes based on identification of mitochondrial and nucleus sequences.

Experimental viscerotropic leishmaniasis is regularly caused by Leishmania tropica promastigotes. In the current investigation, the viscerotropic pathogenicities of Leishmania major amastigotes and promastigotes were compared and evaluated based on their heterogeneity traits and number of inoculated parasites in experimental mammalian hosts. Serous exudate from 50 patients was infected, 44 with L. major and 6 with L. tropica; only BALB/c mice inoculated with 1-2 × 10(4-6) L. major amastigotes manifested cutaneous lesions at the base of their tails. Five out of the 44 BALB/c mice inoculated with L. major died of sequela of viscerotropic adverse effect, while 2 × 10(6) L. major promastigotes showed viscerotropic signs in four BALB/c mice. The sequencing of the Cyt b gene showed a strain of L. major (GenBank accession number KM393221: haplotype diversity 0.9) containing two codon mutations, 86 and 126 in dead mice, whereas no significant mutant was observed in internal transcribed spacer (ITS)-ribosomal DNA (rDNA) sequences (haplotype diversity 0). Findings show that a lower dose of L. major amastigotes than promastigotes has more potential viscerotropic intensity in susceptible hosts. It illustrates that testing Cyt b as an evolutionary mitognome marker because of having its semi-conserved structure and low copy number is able to be utilized in the discrimination of new mutants.

Prevalence and Mean Intensity of Anisakidae Parasite in Seafood Caught in the Mediterranean Sea Focusing on Fish Species at Risk of Being Raw-consumed. A Meta Analysis and Systematic Review.

OBJECTIVE: To assess the prevalence and mean intensity of anisakids in seafood caught in the Mediterranean Sea, focusing on fish species at risk of being raw-consumed. DESIGN: Systematic review and meta-analysis of studies published from 1960-2012. STUDY SELECTION: Main criteria for the inclusion of studies were as follows: Findings of anisakid larvae, in both muscles and viscera; fish species for human consumption caught in the Mediterranean Sea; prevalence and mean intensity data for each species; and sample size equal to or more than 40 fishes. RESULTS: Twelve studies were identified. Among these, four studies considered the following three fish species that are often consumed raw or preserved lightly, or not cooked thoroughly: anchovy, pilchard, and Atlantic mackerel. DATA SYNTHESIS: All pooled analyses were based on the random-effect model. Anisakids prevalence in fish muscle was 0.64% (P < 0.0001), in viscera it was 1.34% (P < 0.0001), and overall prevalence was 0.95% (P < 0.0001). Mean intensity in muscle was 2.31 (P = 0.0083), in viscera it was 1.55 (P = 0.0174), and overall it was 1.81 (P < 0.0005). Heterogeneity indices (I(2)) were significantly high with the exception of viscera mean intensity. CONCLUSIONS: Anchovy, pilchard, and Atlantic mackerel have a low prevalence and mean intensity of anisakidae larvae in both viscera and muscles. Mean Intensity was also low.

Fatal Toxoplasma gondii infection in the giant panda.

Toxoplasma gondii can infect nearly all warm-blooded animals. We report an acute fatal T. gondii infection in the endangered giant panda (Ailuropoda melanoleuca) in a zoo in China, characterized by acute gastroenteritis and respiratory symptoms. T. gondii infection was confirmed by immunological and molecular methods. Multilocus nested PCR-RFLP revealed clonal type I at the SAG1 and c29-2 loci, clonal type II at the SAG2, BTUB, GRA6, c22-8, and L358 loci, and clonal type III at the alternative SAG2 and SAG3 loci, thus, a potential new genotype of T. gondii in the giant panda. Other possible pathogens were not detected. To our knowledge, this is the first report of clinical toxoplasmosis in a giant panda.

Helminth Parasites of Juvenile Green Turtles Chelonia mydas (Testudines: Cheloniidae) in Brazil.

The present study offers a parasitological analysis of juvenile individuals of the green turtle ( Chelonia mydas ) found on the Brazilian coast between 2004 and 2011. Helminths were found in 90 out of 136 individuals (66.2%, CI = 57.7-74.0). In total, 29,411 helminths were collected, belonging to the families Brachycoeliidae, Cladorchiidae, Microscaphidiidae, Pronocephalidae, Rhytidodidae, and Spirorchiidae. Mean species richness was 4.74 (CI = 4.03-5.46), the mean intensity was 327 (CI = 223-489), and the mean abundance was 216 (CI = 146-339). This study also reports new geographical records for: Angiodictyum longum, Angiodictyum parallelum, Rameshwarotrema uterocrescens, Pyelosomum cochlear, Schizamphistomum scleroporum, Cymatocarpus solearis, and Neospirorchis sp. This is the first analysis of helminth composition in juveniles of green turtles.

[Disseminated cysticercosis: report of three cases in Togo]. / Cysticercose disséminée: trois cas au Togo.

We report 3 cases of disseminated cysticercosis (DC) in adult male subjects in Togo. All had consulted in dermatology for asymptomatic subcutaneous nodules. The diagnosis was confirmed by histology of a resected nodule. Computed tomography allowed us to bring out the widespread dissemination of cysticerci. The skin, brain, muscle, eye, thyroid, and pleura were the affected organs. Treatment was based on albendazole and betamethasone, with adverse side effects in 2 of our 3 patients. Our 3 observations seem to be the first of their kind in Togo. The mechanism of contamination in these disseminated forms is not yet elucidated, however ingesting a gravid proglottis could be the basis of the widespread dissemination of cysticerci in the body. No consensus has yet been established in the treatment of DC and the management should follow the guideline for treatment of neurocysticercosis and ocular cysticercosis.

Antigenicity of Anisakis simplex s.s. L3 in parasitized fish after heating conditions used in the canning processing.

BACKGROUND: Some technological and food processing treatments applied to parasitized fish kill the Anisakis larvae and prevent infection and sensitization of consumers. However, residual allergenic activity of parasite allergens has been shown. The aim here was to study the effect of different heat treatments used in the fish canning processing industry on the antigen recognition of Anisakis L3. Bigeye tuna (Thunnus obesus) and yellowfin tuna (Thunnus albacares) were experimentally infected with live L3 Anisakis. After 48 h at 5 ± 1 °C, brine was added to the muscle, which was then canned raw (live larvae) or heated (90 °C, 30 min) (dead larvae) and treated at 113 °C for 60 min or at 115 °C for 90 min. Anisakis antigens and Ani s 4 were detected with anti-crude extract and anti-Ani s 4 antisera respectively. RESULTS: Ani s 4 decreased in all lots, but the muscle retained part of the allergenicity irrespective of the canning method, as observed by immunohistochemistry. Dot blot analysis showed a high loss of Ani s 4 recognition after canning, but residual antigenicity was present. CONCLUSION: The results indicate that heat treatment for sterilization under the conditions studied produces a decrease in Ani s 4 and suggest a potential exposure risk for Anisakis-sensitized patients.

Monsters of the sea serpent: parasites of an oarfish, Regalecus russellii.

Examination of a small portion of the viscera of an oarfish ( Regalecus russellii ) recovered from Santa Catalina Island, southern California, revealed numerous tetraphyllidean tapeworm plerocercoids, Clistobothrium cf. montaukensis; 2 juvenile nematodes, Contracaecum sp.; and a fragment of an adult acanthocephalan, family Arhythmacanthidae. This suggests that the fish was relatively heavily parasitized. The presence of larval and juvenile worms suggests that oarfish are preyed upon by deep-swimming predators such as the shortfin mako shark, Isurus oxyrinchus , known to be a definitive host for the adult tapeworm, and also by diving mammals such as sperm whales, Physeter catodon L., hosts of Contracaecum spp. nematodes.

Short report: Genetic variation of Echinococcus canadensis (G7) in Mexico.

We evaluated the genetic variation of Echinococcus G7 strain in larval and adult stages using a fragment of the mitochondrial cox1 gen. Viscera of pigs, bovines, and sheep and fecal samples of dogs were inspected for cystic and canine echinococcosis, respectively; only pigs had hydatid cysts. Bayesian inferences grouped the sequences in an E. canadensis G7 cluster, suggesting that, in Mexico, this strain might be mainly present. Additionally, the population genetic and network analysis showed that E. canadensis in Mexico is very diverse and has probably been introduced several times from different sources. Finally, a scarce genetic differentiation between G6 (camel strain) and G7 (pig strain) populations was identified.

Immunization of Wistar female rats with 255-Gy-irradiated Toxoplasma gondii: preventing parasite load and maternofoetal transmission.

Toxoplasmosis, caused by an obligate intracellular protozoan parasite, Toxoplasma gondii, is an worldwide parasitic disease, with significant importance for animal production and considerable impact to the public health. This study was aimed to evaluate the dynamic of the distribution of T.gondii in tissues of female Wistar rats and their puppies tissues, after the immunization by oral rote with irradiated tachyzoites. One week after pregnancy confirmation, rats was challenged by gavage with T. gondii bradyzoites, oocysts or tachyzoites of T. gondii. Forty-eight pregnant rats were grouped as follow: immunized and challenged with bradyzoites (BZ*); non-immunized and challenged with bradyzoites (BZ); immunized and challenged with oocysts (OC*); non-immunized and challenged with oocysts (OC); immunized and challenged with tachyzoites (TZ*); non-immunized and challenged with tachyzoites (TZ); only immunized (I); control group (C). After parturition the rats were sacrificed and the tissues were researched for the DNA of T. gondii by polymerase chain reaction (PCR) and the parasite load determined by the quantitative PCR (qPCR). It was verified that the immunization with irradiated tachyzoites of T. gondii induced the reduction of parasitic load in most organs analyzed, although not prevent the establishment of infection with the parasite. And also, the immunization showed a favorable effect on the birth rate and litter size.