人工消化法检验旋毛虫效果及其对肌幼虫的影响

Evaluation of artificial digestion method on inspection of meat for Trichinella spiralis contamination and influence of the method on muscle larvae recovery

目的观察人工消化法检验旋毛虫的效果及对肌幼虫活性、感染性的影响。方法将小鼠感染100条肌幼虫后30 d剖杀,分别应用3组消化法检验,即:消化2 h组(磁力搅拌法)、消化12 h组、消化20 h组,每组取肉样10份,每份含300个囊包,消化后分别计数每份肉样的幼虫数;同时对幼虫活性进行观察。40只昆明小鼠随机分为对照组和3个消化组(消化2、12、20 h组),共4组,每组10只。对照组:每鼠感染100个囊包;消化组:将3组方法收集的幼虫分别感染小鼠,每鼠经口感染100条幼虫。感染后30 d剖杀,取膈肌压片镜检,并用磁力搅拌法收集幼虫、计数。结果消化2、12、20 h组的幼虫检出率分别为78.47%、76.73%、68.63%,死亡率分别为0.59%、4.60%、7.43%。3组收集的幼虫分别感染小鼠,30 d后剖杀,与对照组相比,消化2、12、20 h组的减虫率分别为60.56%、61.94%、73.07%。结论磁力搅拌法(消化2 h)在幼虫检出率、幼虫活性、幼虫感染性等方面均优于消化12、20 h实验组,为进行旋毛虫检验和动物实验,优先选择的方法。

Objective To evaluate the effect of artificial digestion method on inspection of meat for Trichinella spiralis contamination and its influence on activity and infectivity of muscle larvae.Methods The mice were inoculated orally with 100 muscle larvae of T.spiralis and sacrificed on the 30th day following the infection.The muscle larvae of T.spiralis were recovered by three different test protocols employing variations of the artificial digestion method,i.e.the first test protocol evaluating digestion for 2 hours（magnetic stirrer method）,the second test protocol evaluating digestion for 12 hours,and the third test protocol evaluating digestion for 20 hours.Each test group included ten samples,and each of which included 300 encapsulated larvae.Meanwhile,the activity of the recovered muscle larvae was also assessed.Forty mice were randomly divided into a control group and three digestion groups,so 4 groups（with 10 mice per group） in total.In the control group,each mouse was orally inoculated with 100 encapsulated larvae of T.spiralis.In all of the digestion test groups,each mouse was orally inoculated with 100 muscle larvae of T.spiralis.The larvae were then recovered from the different three test groups by the artificial digestion protocol variations.All the infected mice were sacrificed on the 30th day following the infection,and the muscle larvae of T.spiralis were examined respectively by the diaphragm compression method and the magnetic stirrer method.Results The muscle larvae detection rates were 78.47%,76.73%,and 68.63%,the death rates were 0.59%,4.60%,and 7.43%,and the reduction rates were 60.56%,61.94%,and 73.07%,in the Test Group One（2-hour digestion）,Test Group Two（12-hour digestion） and Test Group Three（20-hour digestion）,respectively.Conclusion The magnetic stirrer method（2-hour digestion method） is superior to both 12-hour digestion and 20-hour digestion methods when assessed by the detection rate,activity and infectivity of muscle larvae.