Two isolates of B. melitensis Rev1 from an ovine foetus and caprine milk confirmed the propensity of Rev1 to be shed in milk and causing abortion in the small ruminants particularly if the timing of vaccination is not optimal.50 The attenuated B. melitensis Rev 1 strain is currently administrated as the exclusive vaccine for the prevention of brucellosis in sheep and goat in Iran. Here, REV1 is linked to abortion.