HEMATOLOGICAL VALUES OF CRAB EATING FOXES (Cerdocyon thous) FROM PANTANAL, MATO GROSSO DO SUL, BRAZIL NATURALLY INFECTED AND NON INFECTED BY Trypanosoma cruzi AND T. evansi

Abstract The aim of this work was to evaluate the influence of sex, seasonality and infections by Trypanosoma cruzi and Trypanosoma evansi on the hematological values of crab-eating foxes (Cerdocyon thous) that inhabit the Pantanal from Mato Grosso do Sul. Between November of 2015 and October of 2016, 48 animals were sampled. The hematological values measured were erythrocyte and leukocyte counts, globular volume and mean corpuscular volume. We considered as parasitized the positive animals for T.cruzi and T. evansi in any of diagnostic tests used. We observed that seven (14.5%) of the crab-eating foxes were parasitized only by T.cruzi, seven by T. evansi, and nine (19%) were coinfected. The parasitized animals by T.cruzi showed a significant increase in leukocyte counts (14.7 x 103) compared to non-parasitized animals (10.4 x 103), parasitized by T. evansi (12.4 x 103) and coinfected (12.9 x 103). We observed a significant difference in relation to mean erythrocyte and mean corpuscular volume values between wet and dry periods: 2.6 x 106 and 165, and 3.4 x 106 and 132, respectively. All presented morphologically unconfirmed macrocytosis.摘要 本研究旨在评估性别、季节节律以及克氏锥虫（Trypanosoma cruzi）、伊氏锥虫（Trypanosoma evansi）感染对栖息于巴西南马托格罗索州潘塔纳尔湿地的食蟹狐（Cerdocyon thous）血液学指标的影响。2015年11月至2016年10月期间，本研究共采集48只食蟹狐的样本。本次检测的血液学指标包括红细胞计数、白细胞计数、红细胞容积（globular volume）及平均红细胞体积（mean corpuscular volume）。本研究将任意一项所用诊断检测结果呈阳性的克氏锥虫或伊氏锥虫感染个体判定为寄生虫感染宿主。结果显示，7只（14.5%）食蟹狐仅感染克氏锥虫，7只仅感染伊氏锥虫，另有9只（19%）为双重感染。与未感染个体（10.4×10³）、仅感染伊氏锥虫个体（12.4×10³）及双重感染个体（12.9×10³）相比，仅感染克氏锥虫的食蟹狐白细胞计数显著升高（14.7×10³）。研究发现，湿季与旱季的平均红细胞计数及平均红细胞体积存在显著差异：湿季对应数值为2.6×10⁶与165，旱季则为3.4×10⁶与132。所有受检个体均表现出形态学上未明确的大红细胞增多症。