0000000000001615
AUTHOR
D. W. T. Crompton
Acanthocephala in fish from the Bothnian Bay, Finland
A sample of 7266 fish from 31 species was obtained from the north-eastern Bothnian Bay, Baltic Sea, from 1975 to 1982. Twenty-six fish species were found to be infected with seven acanthocephalan species identified as Echinorhynchus salmonis, E. bothniensis, E. borealis, E. gadi, Acanthocephalus anguillae, A. lucii and Neoechinorhynchus rutili. Acanthocephalus lucii was the only acanthocephalan not to attain sexual maturity M at least one species of fish. Fourteen new host records were found for E. bothniensis. A total of 1576 acanthocephalan infections was found; in most cases these were single species infections, but in 108 cases infections of two, and in two cases of three species were o…
Ovarian development of Corynosoma semerme (Acanthocephala) during experimental infections in rats.
SUMMARYThe general structure and aspects of the development of the ovaries of the palaeacanthocephalan Corynosoma semerme were studied by transmission electron microscopy using worms varying in age from 18 to 90 h obtained from experimental primary infections in hydrocortisone-treated rats instead of seals, which serve as the natural definitive hosts. The observations can be interpreted to show that the immature ovaries become transformed relatively rapidly from cellular spheres to the more complex mature ovaries consisting of the supporting and oogonial syncytia and the germ-line cells. The supporting syncytium developed before the oogonial syncytium. The cytological appearance of ovaries …
Ovarian tissue in juvenile palaeacanthocephalans: Corynosoma semerme, C. strumosum and Echinorhynchus gadi
SUMMARYThe structure of the ovarian tissue in juvenile Corynosoma semerme and C. strumosum from a fish paratenic host and in the cystacanth stage of Echinorhynchus gadi from an amphipod intermediate host was investigated by means of transmission electron microscopy. The species were obtained from hosts living in the Baltic Sea. The observations indicate that ovarian development was more advanced in cystacanths of E. gadi than in juveniles of C. semerme and C. strumosum. Free ovaries were present in E. gadi with an obvious supporting syncytium and surface microvilli. The biological significance of the different stages of ovarian development in these species is discussed briefly in relation t…