Department of Parasitology, Medical College, Zhengzhou University, Zhengzhou, The People's Republic of China.
Foodborne Pathog Dis. 2012 Jan;9(1):27-31. doi: 10.1089/fpd.2011.0985. Epub 2011 Oct 11.
Artificial digestion method is widely used for the detection of Trichinella larvae (mainly the mature larvae, e.g., encapsulated larvae in encapsulated Trichinella) in meat. The previous studies demonstrated that Trichinella spiralis pre-encapsulated larvae (PEL) at 14-18 days postinfection (dpi) had the infectivity to new hosts. However, to our knowledge, there is no report on the detection methods of PEL in meat. The purpose of this study was to compare the efficiency of artificial digestion and Baermann's methods for detection of T. spiralis PEL in meat, and to test the factors affecting the sensitivity of the two methods. Forty-five male Kunming mice were randomly divided into 3 groups (15 mice per group), and each group of mice was orally inoculated with 20, 10, or 5 muscle larvae of T. spiralis, respectively. All infected mice were slaughtered at 18 dpi, and the muscles were minced. The digestion method that was recommended by International Commission on Trichinellosis and Baermann's method were used to detect the PEL in the infected mice. The detection rate of PEL in both mice infected with 20 muscle larvae by digestion and Baermann's method was 100% (15/15); the detection rates of PEL in mice infected with 10 larvae by the two methods just mentioned were 93.33% (14/15) and 100% (15/15), respectively; when the mice infected with 5 larvae were tested, the different detection rate of PEL was achieved by using digestion method (63.33%) and Baermann's method (100%). Additionally, the number of PEL collected from the mice infected with 20, 10, or 5 larvae by Baermann's method was greater than that by digestion methods. The mortality of PEL increased along with the prolongation of digestion duration, because the PEL were not resistant to enzymatic digestion. The results revealed that the Baermann's method is superior to the digestion methods for detection of T. spiralis PEL in muscle samples with low-level infections.
人工消化法广泛用于检测肉中的旋毛虫幼虫（主要是成熟幼虫，例如包囊旋毛虫中的包囊幼虫）。先前的研究表明，感染后 14-18 天的旋毛虫预包囊幼虫（PEL）具有感染新宿主的能力。然而，据我们所知，目前尚无关于肉中 PEL 检测方法的报道。本研究旨在比较人工消化法和巴氏法检测肉中旋毛虫 PEL 的效率，并检测影响两种方法敏感性的因素。45 只雄性昆明小鼠随机分为 3 组（每组 15 只），每组小鼠分别口服感染 20、10 或 5 条旋毛虫肌肉幼虫。所有感染小鼠于 18dpi 处死，肌肉组织绞碎。采用国际旋毛虫病委员会推荐的消化法和巴氏法检测感染小鼠的 PEL。用消化法和巴氏法检测感染 20 条肌肉幼虫的小鼠 PEL 的检出率均为 100%（15/15）；用上述两种方法检测感染 10 条幼虫的小鼠 PEL 的检出率分别为 93.33%（14/15）和 100%（15/15）；当感染 5 条幼虫的小鼠进行检测时，消化法（63.33%）和巴氏法（100%）的 PEL 检出率不同。此外，用巴氏法从感染 20、10 或 5 条幼虫的小鼠中收集的 PEL 数量多于消化法。随着消化时间的延长，PEL 的死亡率增加，因为 PEL 不耐酶消化。结果表明，巴氏法优于消化法，用于检测低水平感染肌肉样本中的旋毛虫 PEL。
