[Diagnostic methods in chlamydial abortion in sheep]

Vast serologic, virologic, and morphologic investigations were carried out into the Chlamydial abortion in sheep. Use was made of the complement-fixation test, passive hemagglutination, chick embryos, electron microscopy, concentration, and purification. The disease was demonstrated on a number of farms with the single or combined employment of the above methods. Discussed was the problem of the diagnostic value of the single and twofold titrations of serum samples from sheep that had miscarried. Prerequisites were developed for the modern use and improvement of the serodiagnostics through the application of more sensitive serologic reactions on the base of purified and concentrated Chlamydial antigens. An important condition to confirm and accelerate the isolation of the strains was said to be the employment of electron microscopy both as a prompt and precise method for the early morphologic identification of the Chlamydial isolates and as a precise control on the serial culturing of the strains. Perfected was the morphologic diagnosis of the Chlamydial abortion in sheep through introducing for the first time of direct electron microscopy of negatively contrasting suspensions and ultrathin cross sections of placentae and viscera of aborted fetuses. The method was shown to be precise, demonstrative, and highly effective. It was employed successfully in sheep with mixed infections--Chlamydia and Salmonella, Chlamydia and Listeria, etc.