and Implications Although past research has proven the organism, Tritrichomonas foetus, can survive freezing technologies utilized in the 1950's, it is unknown if it can survive freezing in liquid nitrogen, the current freezing media for bovine semen. Live organisms were identified after thawing in five of the twelve straws evaluated. Between 0.5 and 6 live organisms were identified in the samples taken from these straws. The number of live organisms within each of these 0.5 mL straws was

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... ted to be between 25 and 300 live organisms. The ability of T. foetus organisms to survive current freeze-thaw techniques for bovine semen suggests that artificial insemination using semen from T. foetus positive bulls poses a significant risk for spreading this pathogen to other cattle in breeding herds.