摘要
Pigs represent an important source of food in many countries, and undercooked pork containing tissue cysts is one of the most common sources of Toxoplasma gondii infection for humans. A magnetic capture method for the isolation of T gondii DNA and quantitative real-time PCR targeting the 529 bp TOXO repeat element were used to estimate the parasite burden in different tissues of pigs experimentally infected with T gondii oocysts, and to determine the predilection sites of T gondii in this host species. The highest concentration of T gondii DNA was found in brain tissues, equivalent to [median] 553.7 (range 3857.7-121.9) parasites per gram, followed by lungs, heart and dorsal muscles with median values corresponding to 0.3 (range 61.3-0.02); 2.6 (range 7.34-0.37) and 0.6 (range 2.81-0.31) parasites per gram of tissue, respectively. Skeletal muscles from fore and hindlimb, liver and kidney presented very low infection burdens equivalent to [median] <= 0.2 parasites per gram of tissues, and no parasite DNA could be detected in the spleen. This study contributes to understanding the value of different pig tissues as a source of T gondii infection for humans and shows that the brain, while not being of major importance as human food source, may represent a first-line selection tissue when performing non-serological surveys (e.g. bioassays, histopathological, immunohistochemical or molecular studies) to detect T. gondii infections in pigs.
- 出版日期2014-4