M33 cluster bomb

The U.S. Army Chemical Corps selected Brucella suis as its first mass-produced biological agent in 1949.

[2] The M33 was an air-released munition: released at high altitude, it would eject its bomblets while still aloft.

[1] In addition, experts calculated that to attain a proper infection rate over an area of one square mile up to 16 separate M33s were required;[1] around 1,500 individual bomblets.

At Dugway Proving Ground, Utah, the Army Chemical Corps exposed over 11,000 guinea pigs to B. suis via air-dropped M33s.

[3] Although the guinea pig trials caused one Chemical Corps general to remark, "Now we know what to do if we ever go to war against guinea pigs",[3] the tests resulted in the realization that the M33 could not compete with the casualty volume caused by atomic weapons.