Brucella melitensis and Chlamydia abortus are the correct answers.

B. melitensis usually infects goats, sheep and camels but is not found in Australia. Though neither are differentials in this case, B. abortus (the agent in bovine brucellosis) was eradicated from Australia in 1989 and B. suis is now the only significant form of brucellosis in Australia. C. abortus is the cause of enzootic abortion in ewes globally, but is not present in Australia. C. psittaci is endemic, and is notifiable depending on State and species. Bluetongue is commonly mistaken as exotic - while some highly pathogenic serotypes are exotic, others are seasonally endemic in northern Australia. These are not a significant risk to livestock due to the lack of a reservoir sheep population in areas where the Culicoides vector is active. The other viral agents (Akabane, Caprine Herpes Virus, Border Disease Virus) are also endemic.