Abstract
Compost manure which is ordinarily found in rural areas of Japan is usually made of various vegetative residues and human nightsoil which is often added as a source of nitrogen. It is necessary to ascertain, therefore, whether the parasite ova and larvae are found living or not in the compost manure, because if they are found living, they must be able to infest human beings which will bring them in contact with such Maces of danger.
It has already been reported by several investigators (Nagano, 1950; Anzai et al., 1951; Sawada et al.., 1951; Kodama et al.., 1951) that the ascaris ova were killed in the course of fermentation which took place in the compost manure. Since those findings, they recommended so-called“compost treatment”as a useful method of the human nightsoil treatment, and we have also come to favour its application on the treatment of the stools separated with a new type of pit privy (Kodama et al., 1951; 1955) .
On the other hand, Mizushima and Yamashita (1952) have noted that the ascaris carriers in a village of Miyazaki Pref., where“compost treatment”of the nightsoil was usual in practice, were very few in number, but on the contrary, there were more hookworm carriers than that of the ascaris. They considered, therefore, that the inf ective hookworm larvae would migrate towards the perphery of the compost heap creeping out of its central area fermenting very actively, and this condition might be quite favourable for them to infest human beings. It has subsequently been proved by an experimental work carried out, by Miyasato and Yamashita (1952) that the hookworm ova would be able to develop into the inf ective stage in the compost manure.
As mentioned above, there are many questions to investigate the migratory behaviour of both hookworm ova and larvae living in the compost manure. To solve those questions, I studied the migration of the inf ective hookworm larvae when their living surroundings were gradually warmed up just like the compost, because it may be sure that the migratory behaviour of the hookworm larvae living in the compost would be controlled by the fermenting temperature which is kept in the course of its fermentation.
