Serological responses to Neospora caninum in experimentally and naturally infected water buffaloes ( Bubalus bubalis)

• Published in: Veterinary parasitology 2005-04, Vol.129 (1), p.21-24
• Main Authors: Rodrigues, A.A.R., Gennari, S.M., Paula, V.S.O., Aguiar, D.M., Fujii, T.U., Starke-Buzeti, W., Machado, R.Z., Dubey, J.P.
• Format: Article
• Language: English
• Subjects: Animals; Antibodies; Antibodies, Protozoan - blood; Brazil - epidemiology; Bubalus bubalis; Buffaloes - parasitology; Coccidiosis - blood; Coccidiosis - epidemiology; Coccidiosis - transmission; Coccidiosis - veterinary; Congenital transmission; Experimental; Female; Fluorescent Antibody Technique, Indirect - veterinary; Injections, Subcutaneous - veterinary; Natural; Neospora - immunology; Neospora caninum; Random Allocation; Seroepidemiologic Studies; Time Factors; Water buffaloes
• ISSN: 0304-4017; 1873-2550
• DOI: 10.1016/j.vetpar.2004.12.024

The water buffalo ( Bubalus bubalis) is an important natural host for Neospora caninum. Serologic responses to N. caninum were studied in experimentally and naturally infected water buffaloes in Brazil. Antibodies were assayed by the indirect fluorescent antibody test (IFAT) using a cut off value of 1:25. Six buffaloes were each inoculated subcutaneously with 5 × 10 6 live culture-derived tachyzoites of the cattle Illinois strain of N. caninum, and two calves were kept as uninoculated controls. Post-inoculation (p.i.) blood samples were collected weekly for 8 weeks and then monthly until 1 year p.i. All inoculated buffaloes developed IFAT titers of 1:100 or more between 7 and 11 days p.i. and the titers remained elevated until 7 weeks p.i. Antibody titers peaked to 1:1600 in 1, 1:800 in 3 and 1:400 in 2, usually by 3 weeks p.i. Antibody titers declined to 1:25 or 1:50 in all the six buffaloes by 12 months p.i. IFAT titers to N. caninum remained at an undetectable level (