Areas where mucocutaneous leishmaniasis, kala-azar and Chagas' disease are prevalent often overlap in Latin America. Due to a variable degree of cross-reactivity between the three etiological agents and antibodies synthesized during the course of the disease, a test able to distinguish between them is greatly needed. Saline-extracted antigen from live Trypanosoma cruzi epimastigotes behaved towards Chagas' disease sera in immunoenzymatic assays (ELISA) with the same specificity and sensitivity as the antigen used routinely for such tests. In tests using mucocutaneous leishmaniasis or kala-azar sera, the live T. cruzi antigen showed a much lower geometric mean titer (GMT) than the standard T. cruzi antigen. In ELISA tests with L. braziliensis antigen a higher GMT was seen with kala-azar sera than with those from cases of mucocutaneous leishmaniasis. Also, sera from Vale do Ribeira leishmaniasis showed higher GMT with an L. donovani antigen than with a homologous one. Such discrepancies were not seen in immunofluorescence tests employing the same sera and antigens.

ABSTRACT. The aim of this study was to investigate antibodies against brucellosis, leptospirosis, bovine rhinotracheitis (IBR/ BoHV-1), bovine viral diarrhea (BVD) and neosporosis through immunodiagnostic. These agents may directly or indirectly compromise the female bovine reproductive tract as well as embryonic and fetal development, therefore we also tried to establish a probable relation between those antibody with the utilization rates of fixed-time embryo transfer (FTET) protocols, with pregnancy rate per embryo transfer (ET) and the occurrence of miscarriages. Embryos were obtained by in vitro fertilization of the ovum and sperm from the Gyr dairy breed, which were transferred to 235 zebu-crossbred cows under FTET protocols. The blood samples to obtain serum were collected by venous puncture from coccygeal vein, only a few days of the completion of ET. For the immunodiagnostic research of brucellosis, leptospirosis, IBR/BoHV-1, BVD and neosporosis, the complement fixation assay, the microscopic agglutination test, virus neutralization, and linked immunosorbent assay to enzymes in conjunction with the indirect immunofluorescence were used. The utilization rates of the FTET protocols related to pregnancy and abortion in D16, D35, and D75 were 67.23%, 34,18% and 20,37% respectively. The immunodiagnostic results related to seropositive animals were obtained for brucellosis (7/235 = 2.89%), leptospirosis (128/235 = 54.47%), IBR (103/235 = 43.83%), BVD (174/235 = 74.04%), and neosporosis (150/235 = 63.82%). In seropositive recipients, there was an observed influence (P < 0.05) of leptospirosis and neosporosis on the rate of protocol utilization of brucellosis on both the pregnancy and abortion rate, and of BVD and IBR on abortion rate.Key words: reproductive, embryo, recipients, cattle. RESUMEN.El estudio tuvo por finalidad evidenciar, mediante técnicas de inmunodiagnóstico, anticuerpos contra Brucelosis, Leptospirosis, Rinotraqueítis Infecciosa Bovina (IBR), Diarrea Viral Bovina (DVB) y Neosporosis, agentes que directa o indirectamente pueden comprometer el tracto reproductor de las hembras así como el desarrollo embrionario y fetal. Se estableció una probable relación entre la presencia de anticuerpos contra los agentes con la tasa de aprovechamiento de protocolos de transferencias de embriones en tiempo fijo (TETF), la tasa de preñez por transferencia de embriones (TE) y la ocurrencia de abortos. Los embriones fueron obtenidos por fertilización in vitro (FIV) a partir de aspiración folicular y semen de toros, ambos de raza Gyr lechero, y tranferidos a 235 vacas receptoras cruzadas con Cebú sometidas a protocolos para TETF. Se obtuvo suero de muestras de sangre mediante venopunción de la vena coccígea solamente en los días de realización de TE. Para evidenciar Brucelosis, Leptospirosis, IBR, DVB y Neospora se emplearon las técnicas de fijación de complemento, seroaglutinación microscópica, seroneutralización y test de inmunoensayo (ELISA) junto con la inmunofluorescencia indirecta (RIFI), respectivamente. El ...