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Ticks parasitize various hosts, including humans, and are known to transmit pathogens that can be harmful not only to animals but also to humans. To evaluate the possible presence of pathogens in ticks, we aimed to collect and identify tick fauna specimens in Lagoa Comprida Municipal Natural Park, an anthropogenic urban area located in Aquidauana, Mato Grosso do Sul, Brazil. A total of 1216 ticks, of which 51.2% were Amblyomma sculptum, 1.2% were Amblyomma dubitatum, and 41% were Amblyomma spp. were collected. These results show that the prevalence of A. sculptum is significantly higher than that of A. dubitatum across all four seasons. Molecular analyses revealed positive samples for the genus Babesia, including the confirmation of Babesia bigemina in an A. sculptum specimen, marking the first record of this relationship. This unexpected finding demands greater attention and deeper analysis in the context of the epidemiology of tick-borne diseases., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The main agents for tick control are chemical acaricides. However, when used without technical guidance, they can lead to environmental damage and the development of resistant tick strains. In this context, vaccines are alternative o be used in integrated tick management format by combining with other effective tools. We isolated RNA from ticks Rhipicephalus microplus, prepared the library, and performed next-generation sequencing; a pipeline analysis was applied to identify the hypothetical proteins having immunogenic potential and their predicted immunogenic peptides. Twelve peptides, ranging from 12 to 38 amino acid residues, containing the selected epitopes from different targets were selected and synthesized in two forms: the pure peptide; and the peptide conjugated to keyhole limpet hemocyanin (KLH) carrier. These peptides were divided into two groups of six peptides each. The antigen formulations (groups 1 and 2) were prepared with conjugated peptides containing 200 µg of each peptide per dose emulsified with Montanide ISA 61VG (SEPPIC); the control treatment had the adjuvant formulation without peptides (group 3). To evaluate the protective efficacy, 15 weaned male calves (Angus breed) aged around 6 months to one year and weighing approximately 200-250 kg were divided into three groups of five animals each; they were immunized thrice, at an interval of 28 days. After immunization, all the calves infested with 15,000 larvae of Rhipicephalus microplus. Peptide epitopes were recognized by antibodies against host-specific IgGs using indirect ELISA. The mean of the antibody level was determined for each group and compared using analysis of variance with two factors (ANOVA). F-test was used to determine the significance of differences observed between the groups. The percentage efficacy was calculated based on the number of ticks, the weight of teleoginas, and the weight and hatchability of the eggs, compared to that in the control group. The evaluation of immunoprotection indicated efficacies of 69 and 51 %, respectively in Group 1 and 2., Competing Interests: Declaration of Competing Interest The authors declare no conflicts of interest with respect to the conduct, authorship, and/or publication of this study., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The objective of this study was to evaluate the survival of Rhipicephalus microplus females under low temperature, to determine the influence of temperature and relative humidity (RH) on the biological parameters of this tick. In total 300 viable engorged female ticks collected from cattle were used. On the day of collection (D0), 30 female ticks were divided into three groups: G1, kept at 28 °C and 80% RH; G2, kept at 20 °C and 80% RH; and G3, kept at 20 °C and 30% RH. The remaining females were stored in a refrigerator at 4 °C. Over the next 9 days (D+1 to D+9), 30 female ticks were removed daily from the refrigerator and distributed among the three treatments. Egg mass, feed conversion rate, egg incubation period, larval hatch rate, number of dead females per group, weight of female tick removed from the refrigerator, and female tick weight loss were recorded. At 20 °C and 80% RH hatching was delayed. Among the female ticks kept in the refrigerator and then allocated to groups G1, G2, and G3, there was a reduction in reproductive efficiency and a rise in mortality as time in the refrigerator increased. The female ticks expressed their best reproductive capacity when subjected to the refrigeration temperature for a maximum of 3 days and then kept at 28 °C and 80% RH. Thus, although female ticks can be stored in the refrigerator before being sent to research centers for use in bioassays, the storage time should be as short as possible, not exceeding 3 days.

Neospora caninum is an obligate intracellular protozoan with canids (Canis domesticus, Canis lupus dingo, Canis latrans, Canis lupus) as its definitive hosts. The objective of this study was to detect anti-N. caninum antibodies in pregnant women seen at referral center for prenatal screening in the state of state Mato Grosso do Sul, Brazil. A total of 188 serum samples from pregnant women provided by the Instituto de Pesquisa, Ensino e Diagnósticos da APAE de Campo Grande (IPED/ APAE) were subjected to IFA test and western blot analysis. The samples were divided into three groups: 23/99 samples from the seropositive group for toxoplasmosis were positive for anti-N. caninum IgG antibodies, and 9/99 positive for IgM; in the HIV group, 7/33 were positive for IgG; and in the HIV+toxoplasmosis group, 13/56 were positive for IgG and two positive for IgM. The seropositivity for IgG was assessed by western blot by testing 43 IFA test positive samples using rNcSRS2 (Nc-p43) as antigen. The serological results of the present study suggest that exposure of these pregnant women to the parasite N. caninum and presence of IgM antibodies are indicative of recent infection. Further studies are needed to establish the possibility of active infection.

More than 70 tick species are found in Brazil, distributed over five genera and including main vectors of infectious disease agents affecting both animals and humans. The genus Amblyomma is the most relevant for public health in Brazil, wherein Amblyomma aureolatum, Amblyomma ovale and Amblyomma sculptum have been incriminated as vectors of Rickettsia and Borrelia pathogens. The objective of this study was to investigate the presence of Rickettsia spp. and Borrelia spp. in ticks in the Brazilian mid-western savannah. DNA extraction, PCR for Borrelia spp. (flgE gene) and Rickettsia spp. (ompA and gltA genes) and subsequent sequencing were performed. A total of 1875 ticks were collected and identified as A. sculptum except for two Amblyomma coelebs ticks. Molecular evidence for Borrelia spp. and Rickettsia parkeri was found in A. sculptum. This is the first molecular evidence for R. parkeri in A. sculptum ticks in the Midwest region and Borrelia spp. circulating in a tick of the Amblyomma genus in Brazil.

Neosporosis primarily affects cattle and dogs and is not currently considered a zoonotic disease. Toxoplasmosis is a zoonosis with a worldwide distribution that is asymptomatic in most cases, but when acquired during pregnancy, it can have serious consequences. The seropositivity rates determined by the indirect fluorescent antibody test for Neospora caninum (N. caninum) and Toxoplasma gondii (T. gondii) were 24.3% (49 samples) and 26.8% (54 samples), respectively. PCR positivity for N. caninum was observed in two samples of cord blood (1%) using the Nc5 and ITS1 gene, positivity for T. gondii was observed in 16 samples using the primer for the B1 gene (5.5% positivity in cord blood and 2.5% positivity in placental tissue). None of the samples showed structures characteristic of tissue cysts or inflammatory infiltrate on histopathology. Significant associations were observed only between N. caninum seropositivity and the presence of domestic animals (p = 0.039) and presence of dogs (p = 0.038) and between T. gondii seropositivity and basic sanitation (p = 0.04). This study obtained important findings regarding the seroprevalence and molecular detection of N. caninum and T. gondii in pregnant women; however, more studies are necessary to establish a correlation between risk factors and infection.

Introduction: Neospora caninum and Toxoplasma gondii belong to the Sarcocystidae family, and both have one definitive and various intermediary hosts. Owing to their weak immune systems, immunocompromised persons might be prone to opportunistic infections. The aim of this study was to investigate the presence of anti- N. caninum and anti- T. gondii antibodies in immunocompromised individuals., Methods: This cross-sectional study investigated the rates of N. caninum and T. gondii , as assessed using immunofluorescent antibody reaction (IFAT) with 1:50 and 1:16 dilution, respectively, in patients with human immunodeficiency virus (HIV)., Results: The seropositivity for N. caninum was 26.1% (81/310) in Mato Grosso do Sul and 31.2% (10/32) in Paraná and for T. gondii was 76.8% (238/310) in Mato Grosso do Sul and 68.7% (22/32) in Paraná., Conclusions: There is evidence of anti- N caninum and anti- T. gondii antibodies in patients with HIV. Other aspects of T. gondii , which is a zoonosis, and N. caninum , which might affect immunodeficient individuals, need to be evaluated and reported.

Neosporosis is of alarming economic concern in the cattle industry. The effectiveness of diagnostic tests for detecting specific antibodies against Neospora caninum is hampered by potential cross-reaction with other coccidia. Use of a single specific antigen might improve test specificity. An indirect enzyme-linked immunosorbent assay (ELISA) was developed using the truncated protein NcSRS2 expressed in Escherichia coli. The ELISA results were compared with those of the indirect fluorescence antibody test (IFAT). Receiver Operating Characteristic (ROC) and Tests in the Absence of a Gold Standard (TAGS) analysis revealed an assay having 96% specificity and 95% sensitivity when applied to 145 positive and 352 negative sera from two distinct cattle populations. Using OD ≤ 0.095 as the cut-off point, the assay's negative and positive predictive values ranged from 98.8% to 50.8% and from 58.8% to 99.1%, respectively, depending on neosporosis prevalence in a given area. The novel ELISA-NcSRS2 format described in the present report constitutes a specific and sensitive method for detecting N. caninum in cattle., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Neospora caninum is an obligate intracellular parasite that can infect domestic and wild canids, ruminants, and horses. The purpose of this study was to evaluate the association between the presence of antibodies to N. caninum and reproductive loss in beef heifers in the South Pantanal region of Mato Grosso, Brazil. A total of 1098 heifers were evaluated from breeding to calving with regard to reproductive performance, and serology for neosporosis was assayed by indirect immunofluorescence reaction. The prevalence of N. caninum in cows that had failed to conceive was 22.13% higher than in those that had conceived (p > 0.0001), indicating a significant correlation between non-conception and presence of anti-N. caninum antibodies. The extraction rates for seropositive and seronegative heifers were 28.24 and 50.12%, respectively, with a statistically significant value (p > 0.0001) that showed a decrease of 44% in the extraction rate of seropositive animals. The results emphasize the importance of diagnosis for monitoring of neosporosis in primiparous cows, and indicators of seropositive females as a factor in strategies for culling the beef cattle herd.

Neospora caninum, an Apicomplexan parasite that can causes abortion, is responsible for considerable economic and reproductive losses in livestock. The purpose of the present study was to determine whether recombinant NcSRS2 is a suitable indirect ELISA antigen for determining specific immune response to N. caninum in sheep. A total of 441 serum samples were subjected to IFAT and rNcSRS2 based-ELISA, with both tests performing similarly. The sensitivity and specificity of indirect ELISA were 98.6 and 98.3%, respectively. The kappa index shows 0.98 concordance between the two tests, which is considered excellent. Seroprevalences of 30.8 and 32.0% were detected by IFAT and indirect ELISA, respectively, showing these tests did not differ significantly on this measure (p > 0.05). Serological analysis showed that HisG tag was detected by Western Blotting recognizing rNcSRS2 protein. The potential value of rNcSRS2-based ELISA as a highly specific and sensitive tool for serological diagnosis is also supported by the strong agreement found between IFAT and ELISA. The results support the potential use of recombinant protein NcSRS2 as an antigen in indirect ELISA in sheep.

The objective of this study was to provide information on the histological characteristics of the gonads of male and female Armases rubripes crabs, and to try to establish a relationship between the microscopic and macroscopic stages previously identified. Thirty-six crabs were collected by hand between February 2003 and January 2004 in banks of Spartina alterniflora on Sahy Beach in Mangaratiba, Rio de Janeiro state, Brazil. The histological analysis of the ovaries of A. rubripes demonstrated a gradual process of development of the oocytes. According to their cellular characteristics, five types of cells were distinguished: oogonia, oocyte I, oocyte II, oocyte III and oocyte IV. The ovaries showed four stages during gonadal activity: stage I (rudimentary), stage II (developing or maturing), stage III (developed or mature) and stage IV (resting). The results of the histochemical analyses showed that the ovaries vary according to the gonad development stage. The histological aspect of one section of the male gonad was always the same in all of the seminiferous tubules, where the lumen of these tubules always contained spermatozoa and/or spermatids. It was not possible to characterize the three stages of gonad development in the males. This agrees with previous reports in the literature. However, in the females there was a relationship between the gonad stages distinguished macroscopically and the results obtained through the histological and histochemical analysis, due to the presence of different cell types, as well as the lysis process and reabsorption of the oocytes in spent females.

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.

Neospora caninum is an obligate intracellular protozoan that can infect domestic and wild canids, as well as ruminants and equines, and is described as causing neuromuscular alteration and death in dogs. Visceral leishmaniasis (VL) is an infectious disease that affects both humans and animals, being caused by protozoan parasites of the genus Leishmania, of which Leishmania (Leishmania) chagasi is found in Brazil -- transmitted by sand flies, such as Lutzomyia longipalpis, in most of the American continent. The immunosuppression caused by VL can promote the occurrence of co-infections with other agents. In order to determine the frequency of N. caninum and its relationship to VL in Campo Grande, MS, Brazil, 345 blood sera were collected from dogs. The sera were submitted to an indirect fluorescent antibody test (IFAT) for detection of anti-N. caninum antibodies and VL antibodies. N. caninum was found in 26.5% of VL-negative dogs and in 29% of VL-positive ones. Among males, it was found in 30.7% of VL-negative animals and in 30.4% of VL-positive ones; among females, in 21% of VL-negative animals and in 27.7% of VL-positive ones. Among juvenile dogs (under 1 year), N. caninum was detected in 10.5% of VL-negative animals and in 11.2% of VL-positive ones. For adult dogs (1 year and older) the results were 31.4% for VL-negative animals and 28.8% of VL-positive ones. The study revealed a statistically significant association with age (chi(2)=9.76, P<0.05) in the N. caninum results for VL-negative animals. No significant correlation in N. caninum seroprevalence was found when VL-positive or VL-negative dogs were compared (chi(2)=0.21, P=0.64). The findings suggest that in Campo Grande N. caninum and VL co-infection is common in dogs, though VL does not appear to enhance susceptibility to N. caninum.