Exposure of Domestic Cats to Distinct Ehrlichia canis TRP Genotypes

Cats naturally exposed to Ehrlichia canis have been described in different regions of the world, but little is known about the genotypes associated with infection in these animals. To detect E. canis-specific antibodies and investigate the E. canis TRP genotypes in cats, serum samples from 76 domestic cats reactive to crude E. canis antigens by the indirect fluorescence antibody test (IFAT) were analyzed by ELISA, using E. canis-specific peptides (i.e., TRP19 and TRP36 /BR/US/CR). Of these, 25 (32.9%) cats reacted to at least one TRP peptide, confirming their specific exposure to E. canis. Eighteen (23.7%) cats reacted to TRP19, 15 (19.8%) to BRTRP36, and 11 (14.5%) to USTRP36, but none of them reacted to CRTRP36. Eight (10.5%) cats reacted to TRP19 but not to any TRP36 genotype, demonstrating the possible existence of a new E. canis genotype infecting felines. Nevertheless, this study provides the first report of anti-E. canis-specific antibodies in domestic cats.

Association between Neospora caninum seropositivity and reproductive disorders in girolando cows

ABSTRACT The aim of this study was to investigate the presence of anti-Neospora caninum antibodies in Girolando cows, in order to evaluate the association between seropositivity and reproductive disorders. Blood samples were collected from 40 dairy cows in their reproductive phase from the cranial superficial epigastric vein. The blood samples were tested using the Indirect Fluorescence Antibody Test (IFAT) to detect anti-N.caninum antibodies. The serological results were used to verify whether there was any association with the manifestation of reproductive disorders based on data from the records of reproductive history from 2017 to 2018 as well as the clinical observations of the herd throughout this study. The Fisher exact test was used to verify the existence of an association between the serology and reproductive disorders, adopting a 95% confidence level. The serological results showed a 27.5% seroprevalence in the herd for N. caninum, however, after statistical analysis, no association between seropositivity and reproductive disorders was found in the evaluated herd. Although the studied population is infected with Neospora caninum, we can infer that anti-Neospora caninum antibodies present in Girolando dairy cows at the UFRRJ Dairy Cattle Facility are not associated with the occurrence of reproductive disorders.

Serological Survey of Neospora caninum and Toxoplasma gondii Co-Infection in Rodents in Northwestern Iran

Background: Our knowledge of the epidemiology of rodents’ parasitic agents in Iran is scarce, although some of these pathogens play an important role in human and veterinary medicine, such as Toxoplasma gondii and Neospora caninum. The purpose of this study was to determine the seroprevalence of Toxoplasma gondii and Neospora caninum in rodents of northwestern Iran between Mar and Dec 2015. Methods: Overall, 157 serum samples from rodents (101 Meriones persicus, 41 Mus musculus, and 15 Cricetulus migratorius) were assayed by the indirect fluorescence antibody test (IFAT) for antibodies to T. gondii and N. caninum Results: We found a prevalence of 20.38% (32/157) for N. caninum, 35% (55/157) for T. gondii. Co-presence of antibodies to N. caninum and T. gondii was found in 10 (6.36%) rodents. A significant association was found between the rodents species and seropositivity to N. caninum (P<0.05) but there was no association with rodents species for T. gondii. The overall prevalence of the aforementioned parasites was higher in male versus female rodents. Conclusion: The high seroprevalence of toxoplasmosis and neosporosis in rodents in the study area has implications for translocation of these infections across wider geographical regions since these rodents are mostly preyed on by cats or dogs; hence, which can transfer the parasite to other hosts.

Toxoplasma gondii in cattle in Brazil: a review

Toxoplasma gondii is an apicomplexan protozoan that is frequently found in both humans and animals worldwide. The aim of this review was to list important aspects of Toxoplasma gondii infection in cattle in Brazil. The frequency of occurrence of T. gondii antibodies in Brazilian cattle ranges from 1 to 89.1%, depending on the region evaluated, based on data from 1978 to 2018. However, some characteristics of T. gondii infection in cattle remain uncertain, such as the role of meat intake in transmitting the parasite to humans. Most information regarding T. gondii infection among Brazilian cattle is limited to evaluations of the frequency of occurrence of antibodies. About 70% of the diagnoses of infection in these ruminants in Brazil are made via the indirect fluorescence antibody test (IFAT). Nevertheless, little is known about the population structure of this protozoan in cattle. It is necessary to expand the studies on toxoplasmosis in cattle, in order to better understand T. gondii infection in these animals and its implications for Brazilian public health.

Occurrences of anti-Toxoplasma gondii and anti-Neospora caninum antibodies in sheep from four districts of Tocantins state, Brazilian Legal Amazon Region

Toxoplasmosis and neosporosis have been recognized as economically important diseases with considerable impact on the livestock industry. Little is known concerning the occurrence of Toxoplasma gondii and Neospora caninum in sheep from Tocantins state, Brazil. Here, we investigated antibodies against these parasites and associated factors in 182 sheep from Araguaína, Santa Terezinha do Tocantins, Arguianópolis and Palmeiras do Tocantins districts, Tocantins. Sheep sera were assayed for T. gondii and N. caninum IgG antibodies by indirect fluorescence antibody test (IFAT), using cut-off point at a dilution of 1:40 and 1:25 respectively. The prevalence of seropositive animal for T. gondii was 13.74% and 13.74% for N. caninum. None of the characteristics studied including reproductive problems, presence of cats, presence of dogs and veterinary care (p>0.05) was associated with occurrence of T. gondii or N. caninum infection. Only breed was identified as associated factor for the occurrence of toxoplasmosis in sheep (p<0.05). The present study is the first report on serum occurrence of T. gondii and N. caninum in sheep from the state of Tocantins, Brazil.

Detection of anti-Toxoplasma gondiiantibodies in carthorses in the metropolitan region of Curitiba, Paraná, Brazil

Toxoplasma gondii, the agent for toxoplasmosis, has worldwide distribution. Horses normally play a secondary role in its life cycle, but movement around urban areas, feeding on grass and the increasing use of carthorses for gathering recyclable material in some urban areas of Brazil may increase their exposure to T. gondii infection. The aim of the present study was to investigate the frequency of anti-T. gondii antibodies in carthorses in the metropolitan region of Curitiba, PR. IgG antibodies against T. gondii were detected using the indirect fluorescence antibody test (IFAT) (titers ≥ 64). Seventeen (17.0%) of the 100 horses sampled were seropositive. There were no statistical differences in relation to sex (p = 0.28) or age (p = 0.15). Our findings suggest that carthorses are exposed to T. gondii infections and that no associations with age or sex exist.

Toxoplasma gondii in experimentally infected Bos taurus and Bos indicus semen and tissues

Eighteen young steers were inoculated with Toxoplasma gondii and randomly distributed into three groups of six animals each: GI, 2.5x10(5) "P" strain oocysts, GII, 5.0x10(6) "RH" strain tachyzoites, and GIII (Control). Clinical, serological and parasitemia exams were realized. Parasite investigation by bioassay and PCR was realized on semen and fragments of skeletal musculature, lymph nodes, brain, retina, spleen, liver, lung, testicle, epididymis and seminal vesicle. Blood and semen samples were collected on days -2, -1, 1, 3, 5, 7, 14 and weekly thereafter, up to postinfection day (PID) 84. The inoculated steers (GI and GII) presented hyperthermia from PID 3 to 16. Antibodies against T. gondii were detected through the indirect fluorescence antibody test (IFAT) on PID 5 (1:16) in both inoculated groups (oocysts and tachyzoites), reaching peaks of 1:4096 on PID 7. Parasitemia outbursts occurred in all infected bovines, principally from PID 7 to 28, independent of the strain and inoculate used. Bioassays revealed the presence of parasites in semen samples of animals infected with oocysts (GI) and tachyzoites (GII) on several experimental days between PID 7 and 84. Tissue parasitism by T. gondii was diagnosed by bioassay and the PCR technique in several organ and tissue fragments. These findings suggest the possibility of sexual transmission of T. gondii in the bovine species.

Prevalence of anti-Neospora caninum antibodies in cattle from the state of Mato Grosso do Sul, Brazil

Neospora caninum is an obligate intracellular parasite that can infect domestic and wild canids, as well as ruminants and equines. It was described in 1988 and has been known as a major cause of abortion in bovines and neuromuscular alterations and death in dogs. To estimate the prevalence of bovine neosporosis in the 22 municipalities of the so-called Estrato 1 subregion of the Brazilian state of Mato Grosso do Sul, blood samples were collected from cows aged 24 months and older, from December 2003 to March 2004. During sample collection, a questionnaire was used to gather data of epidemiological interest. The samples were subjected to serological diagnosis (indirect fluorescence antibody test - IFAT). Prevalences of 14.9% (449/2488) and 69.8% (143/205) were found for the animals and herds sampled, respectively. The variable found to be associated with seropositivity to N. caninum was abortion (OR 2.52; CI 1.25-5.06). The results revealed the presence of infection by N. caninum in the herds investigated, drawing attention to its role as a potential cause of abortion in cattle in Mato Grosso do Sul.

Clinical, epidemiological and laboratory criteria for the diagnosis of human cysticercosis in Brazilian patients

Cysticercosis (CC) is a polymorphous disease, which makes its diagnosis difficult. This study had the objective of evaluating the clinical, epidemiological and laboratory criteria in human CC. An epidemiological questionnaire was applied, and indirect fluorescence antibody test (IFAT) and ELISA-IgG were utilized together with computerized tomography and/or magnetic resonance imaging on 90 patients with clinical signs suggestive of neurocysticercosis (NCC). Most patients had previously lived under deficient basic sanitary conditions. The imaging techniques showed that 92.2% of the cysticerci were in the cerebral parenchyma, 5.5% had a ventricular location, 1.1% were periventricular and 1% was ocular. The cysticerci were observed to be predominantly in the inactive phase. Seropositivity to the IFAT and/or ELISA was shown by 32.2% (29/90). Of the 29 seropositive patients, 72.4% presented cysticerci in the inactive form, and of the 61 seronegative patients, 78.7% also presented cysticerci in the inactive form. There was no correlation between active CC and seropositivity, since 72.4% of the seropositive patients presented calcified cysticerci. The results demonstrated that imaging techniques contributed significantly to elucidate the laboratorial diagnosis and to evaluate the stage of cysticercus development.

Cytoplasmic, Nuclear, and Platelet Autoantibodies in Human Granulocytic Ehrlichiosis Patients

Serum samples from patients with confirmed human granulocytic ehrlichiosis (HGE) were tested for cytoplasmic, nuclear, and platelet autoantibodies and rheumatoid factor. The indirect fluorescence antinuclear antibody test on Hep-2 cells demonstrated antinuclear titers of ≥40 and ≥160 in 44 and 10%, respectively, of serum samples from HGE patients. Two patients (4%) had anticytoplasmic (mitochondrial and spindle apparatus) antibodies with a titer of 80 and two patients (4%) had anticytoplasmic (mitochondrial) antibodies with a titer of 160 or greater. Flow cytometry was used to demonstrate antiplatelet antibodies in 80% of first serum samples from HGE patients. Rheumatoid factor was not detected. Nuclear and cytoplasmic autoantibodies are a major cause of interference when the indirect fluorescence antibody test is used to detect fluorescence of morulae inEhrlichia-infected equine neutrophils or HL-60 promyelocytes. Antiplatelet antibodies may contribute to the profound thrombocytopenia which is a characteristic laboratory feature during the acute phase of HGE infection. Whether autoantibodies precede infection or are caused by immune activation of HGE deserves further study.