The author divised a new method to obtain aseptic encysted larvae of dog hookworms, which was described in the 1st report of theses studies. As no description on the cultivation of the encysted larvae of the hookworm in vitro has been found, the author achieved their further cultivation with a new method, as follow.
The aseptic encysted larvae are cultivated anew in No.4 glassfilter with dog serum containing hemoglobin produced by hemolysis of erythrocytes.
The medium is added with a small amount of penicillin and streptomycin powder and a few drops of 0.005% merzonin solution to prevent a putrefaction. The cultivation fluid, namely hemolytic serum, is exchanged daily for 17 days.
After one night all larvae ecdysed. After 7 days the author found the larvae with the thick coating, notchy cyst, partially casting off the thick notchy cyst and also the thick saw-like cyst mixed with the thin ecdysis, but found no larvae with the origin oral capsel. Thick, notchy encysted larvae were still found after 17 days, but the body of the larvae had not grown any longer.
After the cultivation of a certain number of larvae for a delinite period, the auther confirmed that the number of cyst predominated that of larvae.
From the above finding it could be inferred that another stage of coating of the larvae is possible before the formation of the origin capsel in addtion to those found in the past.

View full abstract