Occurrence of anti-Toxoplasma gondii antibodies and risk factors associated with infection in equids slaughtered for human consumption in Brazil

Abstract Toxoplasmosis is a worldwide zoonosis caused by Toxoplasma gondii. Ingestion of raw/undercooked meat is considering an important route of infection. Consumption of meat from equids is common in European and Asian countries and an increase in Brazil has been observed. The aim of this study was to evaluate occurrences of anti-T. gondii antibodies and risk factors relating to infection in equids slaughtered for human consumption in Minas Gerais, Brazil. Blood samples from 192 horses and 208 donkeys were collected in the exsanguination area during the slaughter. Serum samples were subjected to the indirect fluorescent antibody test (IFAT). Association analysis was performed using Pearson’s chi-square test (χ2) or Fisher’s exact test, to evaluate risk factors relating to the prevalence of seroreagents. Antibodies against T. gondii were found in 13.5% of the equids, with higher occurrence in horses (18.75%) than in donkeys (8.65%). Associations between seropositivity and the following variables were found (p ≤ 0.05): species, animal origin, purpose of rearing and source of water for animal consumption and contact with cats. Farms need to implement preventive measures to control T. gondii infection in these species and avert transmission of the parasite to the human population that will consume their meat.

摘要 弓形虫病（Toxoplasmosis）是一种由刚地弓形虫（Toxoplasma gondii）引起的全球性人畜共患病。生食或未充分煮熟的肉类摄入被认为是重要的感染途径。马属动物肉类的消费在欧亚国家较为普遍，且在巴西呈现上升趋势。本研究旨在评估巴西米纳斯吉拉斯州供人类食用的屠宰马属动物中抗刚地弓形虫抗体的检出情况，以及与感染相关的危险因素。研究在屠宰场的放血区域采集了192匹马和208头驴的血液样本，血清样本采用间接荧光抗体试验（indirect fluorescent antibody test, IFAT）进行检测。采用皮尔逊卡方检验（Pearson’s chi-square test, χ²）或费希尔精确检验（Fisher’s exact test）进行关联分析，以评估血清阳性率的相关危险因素。结果显示，13.5%的马属动物样本检出抗刚地弓形虫抗体，其中马的阳性率（18.75%）高于驴（8.65%）。研究发现血清阳性情况与以下变量存在显著关联（p≤0.05）：动物种类、动物来源、饲养用途、动物饮水来源以及与猫的接触情况。养殖场所需采取针对性防控措施，以控制此类动物的刚地弓形虫感染，阻断寄生虫向食用其肉类的人群传播。