Fidelis Junior Otavio Luiz, Sampaio Paulo Henrique, Machado Rosangela Zacarias, André Marcos Rogério, Marques Luiz Carlos, Cadioli Fabiano Antonio
Faculdade de Ciências Agrárias e Veterinária, Universidade Estadual Paulista, Jaboticabal, SP, Brasil.
Faculdade de Medicina Veterinária, Universidade Estadual Paulista, Araçatuba, SP, Brasil.
Rev Bras Parasitol Vet. 2016 Jan-Mar;25(1):69-81. doi: 10.1590/S1984-29612016013. Epub 2016 Mar 18.
Infections by Trypanosoma vivax cause great losses to livestock in Africa and Central and South Americas. Outbreaks due this parasite have been occurred with increasing frequency in Brazil. Knowledge of changes caused by T. vivax during the course of this disease can be of great diagnostic value. Thus, clinical signs, parasitemia, hematologic and biochemical changes of cattle experimentally infected by this hemoparasite were evaluated. Two distinct phases were verified during the infection - an acute phase where circulating parasites were seen and then a chronic phase where fluctuations in parasitemia were detected including aparasitemic periods. A constant reduction in erythrocytes, hemoglobin and packed cell volume (PVC) were observed. White blood cells (WBC) showed pronounced changes such as severe neutropenia and lymphopenia during the acute phase of the illness. Decreases in cholesterol, albumin, aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and increases in glucose, globulin, protein, and alkaline phosphatase (ALP) were observed. The "Lins" isolate of T. vivax showed pathogenicity for cattle, and intense parasitemia was detected in the early stages of infection. Circulating parasites were detected for about two months. The most evident laboratory abnormalities were found in WBC parameters, including thrombocytopenia.
间日锥虫感染给非洲以及中南美洲的家畜造成了巨大损失。在巴西，由这种寄生虫引发的疫情发生频率不断增加。了解间日锥虫在该病病程中所引起的变化具有重要的诊断价值。因此，对感染这种血液寄生虫的牛的临床症状、寄生虫血症、血液学和生化变化进行了评估。在感染过程中验证了两个不同阶段——急性期可观察到循环寄生虫，随后是慢性期，在此期间检测到寄生虫血症波动，包括无寄生虫血症期。观察到红细胞、血红蛋白和红细胞压积（PVC）持续减少。白细胞（WBC）表现出明显变化，如在疾病急性期出现严重中性粒细胞减少和淋巴细胞减少。观察到胆固醇、白蛋白、天冬氨酸转氨酶（AST）、乳酸脱氢酶（LDH）降低，葡萄糖、球蛋白、蛋白质和碱性磷酸酶（ALP）升高。间日锥虫的“林斯”分离株对牛具有致病性，在感染早期检测到强烈的寄生虫血症。循环寄生虫被检测到约两个月。在白细胞参数中发现了最明显的实验室异常，包括血小板减少。
