Background: Leishmania is a single cell parasite causing leishmaniasis, which is a common disease between humans and animals. Due to the importance of in-vitro culture of the parasite in leishmania research, developing new methods for in-vitro cultivation of the parasite has always been a goal for leishmania researchers. The main objective of this study was to use sheep and bovine hydatid cyst fluids as alternatives for fetal calf serum (FCS) in leishmania in-vitro culture.

Materials and Methods: A total of 1 million leishmania promastigotes were added to 4 flasks as follow. A flask containing DMEM medium with 10% fetal bovine serum, a flask containing DMEM and 10% sheep hydatid cyst fluid, a flask containing DMEM medium with 10% bovine hydatid cyst fluid and a flask containing DMEM medium alone. After 2, 4, 7, 9, 11, 21 and 24 days, the number of parasites were counted and compared.

Results: The result of this study showed that, DMEM medium enriched with 10% sheep hydatid cyst fluid in 168 hours and medium enriched with 10% bovine hydatid cyst fluid in 96 hours can act as a good alternative for  fetal bovine serum in the culture Leishmania major.

Conclusion: The results showed that sheep and bovine hydatid cyst fluid can be used as alternatives to FCS for dense cultivation of leishmania. The results also showed that, the growth of promastigotes in medium enriched with bovine cyst fluid is more rapid than the medium enriched with sheep cyst fluid in the beginning of cultivation.