两株近交小鼠对周期型马来丝虫的易感性

SUSCEPTIBILITY OF TWO INBRED MOUSE STRAINS TO INFECTION WITH PERIODIC BRUGIA MALAYI

于长爪沙鼠体保种的周期型马来丝虫,其感染性幼虫(100条/只)接种于BALB/cCR和BALB/cJ两株小鼠腹腔内,都获得感染成功。在95只BALB/cCR株鼠(45,50)中,显性感染者8只(4,4),占8.42％;隐性感染者34只(17,17),占35.79％。共检获成虫110条,每鼠检获1—11条,平均2.62条。在30只BALB/cJ株鼠(18,12)中,12只雌鼠全部阴性;18只雄鼠中,2只为显性感染,4只为隐性感染,共检获成虫18条,每鼠检获1—5条,平均3.0条。两株小鼠中的10只显性感染鼠,有2只腹腔液内首次发现微丝蚴是在感染后80天,其最短潜隐期约为75天。

Of 13 mouse strains tested, BALB/c mice (including BALB/cCR and BALB/cJ strains) were the most susceptible for the development of the 3rd-stage larvae of periodic Brugia malayi. Ninety five BALB/cCR mice (45♂, 50♀) were inoculated i.p. with 100 infective larvae each. Microfilariae (mff) were found in the peritoneal fluid of 8 mice (4♂, 4♀), with a mean patent infection rate of 8.42%, Out of the 95 inoculoted mice necropsied 140-316 days post inoculation (p.i.), 34(17♂, 17♀) harbored only adult worms with no mff in the peritoneal fluid or blood with an occult infection rate of 35.79%. Altogether one hundred and ten (59♂, 51♀) adult worms were recorvered from both the 8 patent and 34 occult mice, with a mean of 2.62 (range 1-11) adult worms recovered per mouse. Seemingly age of mice had an important effect on susceptibility. Patent infection rate was higher in neonate mice than in the other 2 age groups of mice at the age of 2-5 and 6-10 days, and none of the mice inoculated at the age of 13-18 days harbored adult worms or mff (see Table).Thirty BALB/cJ mice were inoculated at the age of 1-79 days, 12 female mice were negative for both mff and adult worms. Of the 18 male mice, however, 4 harbored adult worms only and 1 harbored both adults and mff. In one of the 2 patent mice, inoculated at the age of 79 days, mff were first detected in peritoneal cavity 80 days p.i. and the mf density rose as high as 7,666 per 100 μl of peritoneal fluid on day 120 p.i. and 4 female and 1 male adult worms were found at autopsy 160 days p.i.. Totally eighteen (8♂, 10♀) adult worms were recovered from both the 2 patent and the four occult mice, with a mean of 3.0 (range 1-5) adult worms per mouse.The numbers of male and female worms recovered from both of the 2 mouse strains were roughly the same (67♂, 61♀). The mean±SE of body length was 28.02±0.72 (range 20.0-44.0) mm for the female worms and 16.87±0.39 (range 11.0-24.0) mm for the males. In 2 of the 10 patent mice, mff were first found in the peritoneal fluid on day 80 p.l., and the shortest prepatent period was about 75 days. Adult worms were found in the peritoneal cavity (60.2%), soaking of the carcass (15.6%), thoracic cavity (9.4%), heart and lungs (10.2%), testes (3.1%), liver (0.78%) and kidney (0.7%) respectively.