Location: Animal Parasitic Diseases LaboratoryTitle: Isolation and genetic characterization of viable Toxoplasma gondii from tissues and feces of cats from the central region of China
|Yang, Yuomg - Henan Agricultural University|
|Ying, Yuging - University Of Maryland|
|Verma, Shiv - Non ARS Employee|
|Cassinelli, Ana - Non ARS Employee|
|Liang, Hongde - Henan Agricultural University|
|Pradhan, Abni - University Of Maryland|
|Su, Chunlei - University Of Tennessee|
|Zhu, Xing-quan - Chinese Academy Of Agricultural Sciences|
Submitted to: Veterinary Parasitology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/11/2015
Publication Date: 7/30/2015
Citation: Yang, Y., Ying, Y., Verma, S., Cassinelli, A., Kwok, O.C., Liang, H., Pradhan, A., Su, C., Zhu, X., Dubey, J.P. 2015. Isolation and genetic characterization of viable Toxoplasma gondii from tissues and feces of cats from the central region of China. Veterinary Parasitology. 211(3-4):283-288.
Interpretive Summary: Toxoplasma gondii is a single-celled parasite of all warm-blooded hosts worldwide. It causes mental retardation and loss of vision in children, and abortion in livestock. Cats are the main reservoir of T. gondii because they are the only hosts that can excrete the resistant stage (oocyst) of the parasite in the feces. Humans become infected by eating under cooked meat from infected animals and food and water contaminated with oocyst. Why some people become ill and even die from toxoplasmosis whereas others remain asymptomatic is largely unknown. Recently, it has been found that certains strains of Toxoplasma are dominant in certain geographic localities. One genotype of Toxoplasma (Toxo DB #9) is most prevalent in China whereas Toxo DB type #2 is most prevalent in USA and Europe. Because most of the literature on toxoplasmosis in cats from China is in Chinese, the authors have summarized their own findings and in the Chinese literature in English. These results will be useful for Parasitologists and epidemiologists.
Technical Abstract: Cats are important in the epidemiology of toxoplasmosis because they are the only definitive hosts that excrete environmentally resistant Toxoplasma gondii oocysts. Little is known of feline toxoplasmosis in China and most of the literature is in Chinese. Here we summarized all published reports on feline toxoplasmosis in English and report first identification of oocyst excretion by naturally infected cats in China. Unfrozen tissues of 42 cats and feces of 360 cats from China were bioassayed in mice for isolation of T. gondii. Antibodies to T. gondii were found in 21 of 42 (50%) of cats by the modified agglutination test (cut-off 1:25). Viable T. gondii was isolated from tissues of eight of 21 seropositive but not from 21 seronegative (<1:25) cats. Viable T. gondii was isolated from feces of one cat. DNA derived from cell cultured tachyzoites of all nine T. gondii isolates was characterized by PCR-RFLP of 10 loci (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico). Four genotypes were found; the genotypes of tissue isolates were ToxoDB#9 in six, ToxoDB#2 in one, and Toxo DB # 17 in one. The fecal isolate was ToxoDB# 1.To our knowledge, the present study is the first isolation of T. gondii from cat feces from China.