Survival of Aegyptianella pullorum, Anaplasma marginale and various parasitic protozoa following prolonged storage in liquid nitrogen

Abstract

Various protozoa species were examined using in vivo and in vitro methods to determine their ability to survive prolonged periods of storage in liquid nitrogen. The following protozoan species were successfully recovered after they had been cryopreserved for a period over 10 years: Trypanosoma lewisi, T. cruzi, T. congolense, T. brucei, T. rhodesiense, T. gambiense, T. evansi, T. equinum, T. equiperdum, Leishmania donovani, Plasmodium berghei, P. praecox (relictum), Babesia rodhaini and B. canis. The longest survival period that has been successfully tested so far is between 5 and 7 years for Eimeria species, for monoxenically (A--C) and axenically grown E. histolytica cultures between 2 and 7 years and trichomonades, including Crithidia sp., between 6 and 8 years. Aegyptianella pullorum was successfully recovered after 6.97 years and Anaplasma marginale after 1.92 years. The freezing techniques are briefly described.

Ultrastructural changes on various Trypanosoma spp. after a 30-year storage period in liquid nitrogen

“…It is known that various protozoans, among them Trypanosoma species, are suitable for cryopreservation (Mühlpfordt 1960;Diamond 1964;Gitatha 1968;Raether and Seidenath 1977). With the continuing development of freezing techniques, the efficiency of cryopreservation increased (Allain 1964;Doebbler 1966;James 1983James , 1986), but freezing injuries leading to a loss of virulence and infectivity nonetheless remained (Michel et al 1979;Schupp et al 1980).…”

The viability of cryopreservedAegyptianella pullorum carpano, 1928 in the vectorArgas (Persicargas) walkerae Kaiser and hoogstraal, 1969

“…The ticks were applied to the chickens, when the parasitaemia had reached levels of approximately 60%. The cryopreserved aegyptianellas had been stored in liquid nitrogen continuously for five years according to the method of Raether and Seidenath (1977).…”