Ying Yuqing, Verma Shiv K, Kwok Oliver C H, Alibana Fatima, Mcleod Rima, Su Chunlei, Dubey Jitender P, Pradhan Abani K
Department of Nutrition and Food Science, University of Maryland, College Park, MD, 20742, USA.
United States Department of Agriculture, Animal Parasitic Diseases Laboratory, Agricultural Research Service, Beltsville Agricultural Research Center, Building 1001, Beltsville, MD, 20705, USA.
Parasitol Res. 2017 May;116(5):1591-1595. doi: 10.1007/s00436-017-5420-3. Epub 2017 Mar 24.
Chickens are considered important in the epidemiology of Toxoplasma gondii. Chicken hearts (n = 1185) obtained from grocery stores were tested for T. gondii infection. Antibodies to T. gondii were assayed in fluid removed from the heart cavity using the modified agglutination test (MAT) at 1:5, 1:25, and 1:100 dilutions. MAT antibodies were detected in 222 hearts at 1:5 dilution and 8 hearts at 1:25 dilution, but none were positive at 1:100 dilution. Seropositive (n = 230, 19.4%) chicken hearts were bioassayed in mice and seronegative (n = 157) chickens were bioassayed in cats. Viable T. gondii was not isolated from any hearts by bioassays in mice. The 2 cats fed 60 and 97 hearts did not excrete T. gondii oocysts. The results indicate a low prevalence of viable T. gondii in chickens from grocery stores. Molecular typing of 23 archived T. gondii strains isolated from free-range chickens from Ohio and Massachusetts using the 10 PCR-RFLP markers including SAG1, SAG2 (5'-3'SAG2 and altSAG2), SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico revealed that seven were ToxoDB PCR-RFLP genotype #1, 11 were genotype #2, one was genotype #3, three were genotype #170, and one was mixed genotype. These results indicate that the clonal genotypes #1 (type II), #2 (type III), and #3 (type II variant) are common in free-range chickens.
鸡在刚地弓形虫的流行病学中被认为很重要。对从杂货店获取的鸡心脏（n = 1185个）进行刚地弓形虫感染检测。使用改良凝集试验（MAT）在1:5、1:25和1:100稀释度下对从心脏腔中取出的液体检测抗刚地弓形虫抗体。在1:5稀释度下，222个心脏检测到MAT抗体，在1:25稀释度下有8个心脏检测到抗体，但在1:100稀释度下均无阳性。对血清阳性的鸡心脏（n = 230，19.4%）在小鼠中进行生物测定，对血清阴性的鸡（n = 157）在猫中进行生物测定。通过在小鼠中的生物测定，未从任何心脏中分离出活的刚地弓形虫。给2只猫分别喂食60个和97个心脏，它们未排出刚地弓形虫卵囊。结果表明，杂货店的鸡中活的刚地弓形虫患病率较低。使用包括SAG1、SAG2（5'-3'SAG2和altSAG2）、SAG3、BTUB、GRA6、c22-8、c29-2、L358、PK1和Apico在内的10种PCR-RFLP标记，对从俄亥俄州和马萨诸塞州的散养鸡中分离出的23株存档刚地弓形虫菌株进行分子分型，结果显示7株为ToxoDB PCR-RFLP基因型#1，11株为基因型#2，1株为基因型#3，3株为基因型#170，1株为混合基因型。这些结果表明，克隆基因型#1（II型）、#2（III型）和#3（II型变体）在散养鸡中很常见。
