Growth and Maturation of the Cestode Hymenolepis diminuta in Bileless Hosts

Tapeworms, with few exceptions (Smyth, 1954), have resisted attempts at in vitro cultivation. Failure of in vitro maintenance is due, in part, to our incomplete knowledge of their normal in vivo requirements. Since the enteric habitat is complex, their total requirements are extremely difficult to determine in normal infections. However, by altering this environment, factor-by-factor, relative dependencies on normal factors may be fractionated. Previous work (cf. von Brand, 1952 for review of literature prior to about 1950) has attempted this fractionation (1) by dietary methods (Beck, 1951; Read and Rothman, 1957), (2) by altering the host's endocrine balance (Beck, 1952; Chandler, et al, 1952; Landt, 1954), (3) by introducing, withholding, or determining the presence of various supplementary food factors (Coleman, 1953, 1956; Dacres, et al, 1953; Kaipainen, et al, 1954a, 1954b), (4) by use of tracer substances (Read, 1950; Nyberg, 1953), and (5) by various in vitro techniques (Hopkins, 1950; Read, 1951; Hopkins, 1952; Garson and Daugherty, 1953; Goldberg and Nolf, 1954; Read, 1956; Daugherty, 1957; Laurie, 1957). These studies, constituting only a part of the many papers on these phases of cestode physiology have given a clearer, but by no means a complete, insight into the role of luminal as compared to mucosal nutrients.