In a statement read on his behalf by the county Environment executive Vivian Sereti, he said close to 200,000 livestock will be vaccinated in the first phase.
Sereti was speaking on Friday during the vaccination launch at Ntulele trading centre.
Tunai said the vaccination is going on simultaneously in Narok East, Narok South, Narok West and Transmara East and will continue up to the end of next month.
The disease has killed thousands of livestock in areas bordering the Maasai Mara Game Reserve.
County director of veterinary services Dr Faith Gacheche said the government's procurement procedures for the vaccines took a long process and the county government had to intervene to save the situation.
Gacheche said the vaccines have also been taken to the Mara region and the exercise will be a routine in the county.