Ebrahim Hosseinabdai - Department of Theriogenology،Faculty of Veterinary Medicine،University of Tehran,Tehran،Iran.
Massoud Talebkhan Garoussi - Department of Theriogenology،Faculty of Veterinary Medicine،University of Tehran,Tehran،Iran.
Ali Reza Khosravi - Mycology Research Center، Faculty of Veterinary Medicine، University of Tehran، Tehran, Iran.
Faramarz Gharaghozloo - Department of Theriogenology،Faculty of Veterinary Medicine،University of Tehran,Tehran،Iran.
Babak Khorramian Toosi - Department of Clinical Sciences، Faculty of Veterinary Medicine، Ferdowsi University of Mashhad،Mashhad، Iran
Farhad Moosakhani - Department of Pathobiology، Veterinary Medicine faculty، Karadj branch, Islamic Azad University، Karadj،Iran.

 BACKGROUND: Prototheca spp. belongs to the family Chlorellaceae and can cause mastitis in dairy cattle herds. Several Prototheca species could be isolated in different parts of the dairy herds. OBJECTIVES: The objectives were to determine: (۱) the investigation status of bulk milk tank Prototheca Spp prevalence in industrial dairy cattle herds in different area of Iran. And (۲). To evaluate the fungal agent prevalence of bulk milk tank of dairy cattle herds in different seasons. METHODS: Bulk milk tank for the presence of Prototheca and fungal agents from ۱۶۵ industrial dairy cattle herds complexes were tested. The population of each herd was about ۸۵۰–۳۵۰۰ Holstein dairy cows. The samples were taken from ۳۲ cities and ۱۶ provinces of Iran, respectively. In total, almost ۶۶۸۰۰ Holstein dairy cows were repre-sented. The population of lactating cows included about ۲۵۸۰۰. Samples were cultured on sabouraud glucose agar (SGA) medium with chloramphenicol (۱۰۰ mg/L). RESULTS: Only ۸ (۴.۸۴%) out of ۱۶۵ samples were isolated for Prototheca spp. It had been isolated in different seasons. They were ۲, ۴, ۱, and ۱ samples in spring, summer, autumn and winter, respectively. Candida, Fusarium, and Trichosporon spp. were isolated from ۱۳۷, ۲ and ۱ samples, respectively. According to the obtained results, Prototheca and fungal agents are present in bulk milk tanks of industrial dairy cattle herds in different provinces of Iran. CONCLUSIONS: It is concluded that exposure to Prototheca and different fungal agents could be common in the dairy cattle herds in Iran. The results are important as dairy cattle health and human sanitation hazar

Bulk milk tank, Dairy cattle herds, fungi, Iran, Prototh