Development of Haemogregarina boueti in the toad Bufo regularis.

Abstract

SYNOPSIS. Haemogregarina boueti França, 1910, was found to be the commonest blood parasite in the common toad, Bufo regularis Reuss, in Egypt. The rate of infection was about 30% (of 689 toads examined).In properly fixed blood films, the parasites were almost exclusively intraerythrocytic. Most characteristic was the encapsulated “elongate” form averaging 22.3 by 6 μ with a more‐or‐less central nucleus and a pointed, slightly bent, posterior end. Infected red cells were conspicuously hypertrophied and their nuclei were markedly displaced and frequently broken into 2‐4 parts.Young and growing blood forms as well as two types of hepatic schizonts are described for the first time.Schizonts of the first type develop in hepatic cells, are 28–30 μ in diameter and produce numerous elongate oval merozoites about 8 × 2.2 μ radially arranged around a residual body about 10 μ in diameter.Schizonts of the second type start their growth in erythrocytes but later complete their development as free bodies in the liver sinusoids. When mature, they are 32–35 μ in diameter and produce a larger number of thin merozoites about 8 × 1.5 μ, surrounding a larger residual body about 19 μ in diameter.