Eimeria Avium and the Diagnosis of Avian Coccidiosis.

Coccidiosis in the turkey

“…He had supervised experiments by Dr C. Guzman, and states ''It had previously been noted that sporulated oocysts obtained from the turkey invariably failed to produce infection in young chickens. This observation made independently, tended to bear out Johnson's (1923) suggestion as to the occurrence of a distinct species of Eimeria in the turkey '' (Tyzze 1929, p. 272). Tyzzer had previously described E. meleagridis (the parasite he believed had been seen by Johnson) in an abstract published in the Journal of Parasitology (Tyzzer, 1927).…”

“…He provided a photograph of an oocyst from the caeca of a turkey to illustrate an article in the journal Poultry Science, but did not name the species involved (Johnson, 1923(Johnson, , 1923(Johnson, /1924.…”

The long view: a selective review of 40 years of coccidiosis research

“…When reflecting on the science being undertaken in the 1970s, it is appropriate to acknowledge the pioneering studies carried out in the 1920s and 1930s by Walter Johnson at the Oregon State University Experiment Station and Ernest Tyzzer at the Harvard Medical School in the 1920s (Johnson, 1923;Johnson, 1923Johnson, /1924Tyzzer, 1929;Tyzzer et al, 1932) upon which the 1970s research on the species and strains of Eimeria was still building. Anyone with an interest in the biology of the avian coccidia is encouraged to read the two seminal texts by Tyzzer (1929Tyzzer ( , 1932 because they give wonderful descriptions of the parasites, contain exquisite drawings and provide data that remain relevant today.…”