Diagnosis of Sarcocystis cruzi, Neospora caninum, and Toxoplasma gondii infections in cattle

Laboratorio de Inmunoparasitología, Cátedra de Parasitología y Enfermedades Parasitarias, Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata, 60 y 118, 1900 La Plata, Argentina.
Parasitology Research (Impact Factor: 2.1). 04/2008; 102(4):671-5. DOI: 10.1007/s00436-007-0810-6
Source: PubMed


The aim of the study was to diagnose Sarcocystis sp. infections in cattle and to detect coinfections by Toxoplasma gondii and/or Neospora caninum. Blood, diaphragm, esophagus, and myocardium from 90 beef cattle from Argentina were collected. Histopathological, immunohistochemical, polymerase chain reaction assays, and direct microscopical examination were carried out. Sarcocysts from myocardium were measured and counted. Indirect fluorescent antibody test (IFAT) for the three protozoans was performed. Sarcocystis cruzi sarcocysts were found in 100% of myocardium samples. Sarcocysts per gram ranged from 8 to 380 with higher values found in adult cattle (p < 0.001). T. gondii and N. caninum were not detected by immunohistochemistry. T. gondii DNA was found in myocardium of 2/20 seropositive animals, while N. caninum DNA was not found. Antibodies against S. cruzi were detected in all samples, those against N. caninum in 73% and against T. gondii in 91% of the samples (IFAT titer > or =25). It is concluded that serology by IFAT is a suitable method to diagnose these protozoan infections due to its specific IgG detection; therefore, IFAT may be a useful tool to evaluate the impact of each protozoan infection in coinfected animals.

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    • "IFAT titers equal or higher than 1:400). Our results contrast with those reported byMoré et al. (2008), where most Argentine cattle showed anti-S. cruzi antibody levels equal to or higher than 1:200. "
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    Full-text · Article · Sep 2015 · Veterinary Parasitology
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    • "Conrad et al. [33] urged caution when interpreting the serologic results if they are to be used in strategies for the control of neosporosis in cattle. In the USA Paré et al. [33], and in Argentina Moré et al. [35] reported that 8/170 (5%) and 1/33 (3%) of seronegative cows gave birth to seropositive calves, respectively. "
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    ABSTRACT: The aim of the present study was to evaluate anti-Neospora caninum antibodies and the vertical transmission rate in naturally infected pregnant zebu beef cows (Bos indicus) reared on pasture. The present study began with 200 cows from four farms (50 cows from each farm), and these animals were submitted to timed artificial insemination (TAI). After ultrasonography, 76 pregnant cows were selected, 22, 15, 22, and 17, respectively, from farms 1, 2, 3, and 4. Blood samples were taken from cows thrice during the first, second, and third trimester of gestation, and a blood sample was collected from 31 calves before colostrum milking. From 76 cows 23 (30.3%) had anti-N. caninum antibodies detected by indirect ELISA (Idexx), and 53 (69.7%) did not. Sixty-four cows that initiated the experiment were negative to N. caninum and 11 became positive either during the second or third trimester of gestation, this mean an infection incidence of 17.2% (11/64). OD for ELISA was higher (OD = 2.08) during the second and third (OD = 2.10) trimesters of pregnancy when compared with the first (OD = 1.81), however, there were no statistical differences (P = 0.45). The vertical transmission was calculated to be 29.0% (9/31), and the risk of vertical transmission of N. caninum in seropositive dams was 26.25 times higher than seronegative animals (OR = 26.25, 2.38 < OR < 289, P = 0.007). In conclusion, the rate of vertical transmission of N. caninum in pregnant zebu beef cows was 29%, and the risk was 26.25 higher in seropositive dams relative to than seronegative animals.
    Full-text · Article · Sep 2014 · Comparative Immunology Microbiology and Infectious Diseases
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    • "Sera were diluted twofold in PBS starting at 1:25 dilution. Positive and negative control sera were used as control (Moré et al. 2008). Positive reactions in sera dilutions ≥1:100 were considered as indicative for the presence of Sarcocystis spp. "
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    ABSTRACT: Water buffalo industry has become a profitable activity worldwide, including the Northeast of Argentina (NEA). However, research on diseases affecting this species is scarce. The aim of the present study was to detect antibodies against Brucella abortus, Leptospira spp., Neospora caninum, Toxoplasma gondii, and Sarcocystis spp. in 500 water buffalo cows from five ranches (100 animals each) in the NEA. Serum samples were tested for B. abortus by fluorescence polarization assay, Leptospira spp. by microagglutination test, and N. caninum, T. gondii, and Sarcocystis spp. by indirect fluorescent antibody tests. Overall, the proportion of seropositive animals was 6.4, 22.2, 42.2, 25.4, and 50.8 % for brucellosis, leptospirosis, neosporosis, toxoplasmosis, and sarcocystosis, respectively. The proportion of seropositive animals for all diseases was statistically different among herds (p < 0.05). Statistical differences were also detected among age groups for brucellosis and neosporosis (p < 0.05). The detection of specific antibodies to B. abortus, Leptospira spp., and several Apicomplexa protozoans in water buffaloes in the NEA is reported in this study.
    Full-text · Article · Jun 2013 · Tropical Animal Health and Production
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