[Detection certainty of the contamination of bull sperm with mycoplasma]

Tests for presence of mycoplasmas were conducted on 20 insemination bulls known as mycoplasma spreaders, with 5 sperm pellet batches of 20 pellets each being investigated for each animal. Mycoplasma contamination was positively recorded from 83 of the above 100 batches. Mycoplasma (M.) bovigenitalium, M. californicum. M. arginini, M. bovirhinis, and Acholeplasma laidlawii were typed by means of indirect immunofluorescent technique, which confirmed the presence also in the GDR of mycoplasma species described in the literature and detected in sperm samples. The solid culturing media used in the above tests, medium-B agar and cattle blood agar with staphylococcal nutrix, proved to be equally suitable for isolation of mycoplasma from sperm samples. Mycoplasma was positively identified in about one third of all pellets/batches tested. 3 pellets to one batch should be sufficient a random sample size from which to obtain information at least very close to real contamination.