镜检法与贝氏法对肉类中旋毛虫成囊前幼虫的检验效果

目的观察镜检法（trichinelloscopy）与贝氏法（Baermann’s technique）对肉类中旋毛虫成囊前幼虫（pre-encap-sulated larvae,PEL）检验的效果。方法将80只昆明小鼠随机分为8组（每组10只）,每只感染旋毛虫肌幼虫300条,感染后14～21d每天剖杀1组,应用贝氏法检查小鼠肌肉中的PEL（9～16日龄）,用镜检法检查膈肌中的PEL,用ELISA检测鼠血清抗旋毛虫抗体。另取12只小鼠,用于观察消化法对旋毛虫感染后17～19d（12～14日龄）PEL存活率的影响。结果小鼠感染旋毛虫后14和15d镜检法幼虫检出率分别为50.0%和89.0%,感染后16～21d检出率均为100%。感染后14～21d贝氏法的检出率均为100%;ELISA检测血清抗体阳性率为11.1%～40.0%。感染后14d贝氏法的PEL检出率与镜检法比较差异有统计学意义（χ^2=5.333,P〈0.05）;观察期间ELISA检测的抗体阳性率均显著低于镜检法和贝氏法的幼虫检出率（χ^2=18.9,P〈0.05）。感染后17～19d,小鼠肌肉消化4h的幼虫存活率均明显低于消化1h的存活率（χ^217=117.56,χ^218=37.48,χ^219=96.73,P均〈0.05）。结论旋毛虫感染后17～19d的成囊前幼虫不能完全抵抗胃蛋白酶的消化作用;对肉类中旋毛虫成囊前幼虫的检疫效果,贝氏法优于镜检法。

Comparison of trichinelloscopy and Baermann＇s technique for the inspection of Trichinella spiralis preencapsulated larvae in meat

Objective To observe the efficiency of trichinelloscopy and Baermann＇s technique for the inspection of Trichinella spiralis pre--encapsulated larvae （PEL） in meat. Methods Eighty male Kunming mice were randomly divided into 8 groups （10 mice per group）. Each mouse was orally inoculated with 300 muscle larvae of T. spiralis. One group of the infected mice were sacrificed daily from 14 21 days post infection （dpi）, and the muscles were cut into pieces. Baermann＇s technique was used to inspect the EEl. at 9 16 days of age in the infected muscle, and it＇s results were compared with those of trichmelloscopy and EI.ISA. Another 12 mice were used to observe the effects of the digestion method on the viability of the Phi. at 12--15 days of age collected on 17-19 dpi. Results When trichinelloscopy was applied to the test. the detection rate of PEL in muscles taken 14 and 15 dpi was 50.0% and 89.0% , respectively, and the detection rate of PEL in muscle taken 16-21 dpi was 100%. On 14--21 d dpi, the detection rate of PEL by Baer mann＇s technique was 100%, while the serum antibody positive rate was only 11. 1% to 40.0%. On 14 dpi,the detection rate of PEL by Baermann＇s technique was higher than that by trichinelloscopy（χ^2= 5. 333, P〈0.05）. The positive rate of ELISA was still obviously lower than that of trichinelloscopy and Baermann＇s technique during the experiment（χ^2=18.9, P〈0.05）. The larval viability of Phi. in muscles on 17--19 days digested for 4 h was evidently lower than that of PEL digested for 1h （χ^217=117. 56,P〈0.05;χ^218=37.48,P〈0.05;χ^219=96.73,P〈0.05）. Conclusion The pre encapsula- ted larvae （PEL） of T..spiralis collected on 17--19 day after infection are not resistant enough to the digestion of pepsin, Baermann＇s technique is superior to trichinelloscopy and EI.ISA for the detection of T. spiralis pre encapsulated larvae in meat.