Study on the course of Cryptosporidium baileyi infection in chickens treated with interleukin-1 or indomethacin.

The effects exerted by human recombinant interleukin-1 beta (hrIL-1 beta) and the prostaglandin inhibitor indomethacin on the course of Cryptosporidium baileyi infection in chickens were studied. Daily oocyst shedding was monitored by a quantitative method throughout the experiment. Humoral immune response to C. baileyi was assessed by ELISA at 3 weeks of age while the level of cellular immune response to phytohaemagglutinin-P (PHA-P) by a skin test at 23 days of age. Parenteral application of hrIL-1 beta decreased oocyst shedding to 62%, but the infection ran a similar course in treated and control birds. The PHA-P skin test demonstrated increased cellular immune reaction in chickens receiving IL-1 beta, but there was no significant difference in the humoral responses of the two groups as detected by ELISA. On the other hand, indomethacin mixed to the feed lessened oocyst shedding to 13.7% and also shortened its duration. Immunological parameters as reflected by PHA-P skin test and ELISA results indicated enhanced cellular but unaltered humoral immune response. These data suggest that the systemic application of interleukin-1 can induce partial protection against C. baileyi in chickens and that prolonged, abundant oocyst shedding is due to an indomethacin-sensitive immunodepression via the prostaglandin pathway.

[Intranuclear development of the macrogametes of the coccidian, Tyzzeria parvula]. / Vnutriiadernoe razvitie makrogamet koktsidii Tyzzeria parvula.

The fine structure of macrogametes of a goose coccidium Tyzzeria parvula has been studied, intranuclear localization of these being discovered. Unlike other coccidia, macrogametes of T. parvula display only one type of wall-forming bodies. Deep invaginations are formed on the surface of macrogametes, in which fragments of host cell nucleoplasm, separated with the membrane of parasitophorous vacuole, are invaginating. They may be connected with process of parasite's feeding.

[Ultrastructure of goose intestinal epithelial cells infected with Eimeria kotlani]. / Ul'trastruktura kletok kishechnogo épiteliia gusia, zarazhennykh koktsidiiami Eimeria kotlani.

The ultrastructure of goose intestinal epithelial cells infected with various stages of E. kotlani has been described. No changes in the ultrastructure of the nucleus and cytoplasm were detected in cells, containing asexual stages. Damage of host cell structures, except Golgi complex, was not observed until gamogenesis. It is suggested that these changes are caused by the intensive "exploitation" of differentiated epithelial cells by large coccidian stages (macro- and microgametocytes). It is concluded that the epithelial cell of the goose, as of other animals, may function beyond crypts without the regulating influence of the nucleus.