Embodiments of a feed additive delivery device, a system comprising a micro weigh machine and the feed additive delivery device, and a method for using the device and system are disclosed. A particular exemplary feed additive delivery device comprised a feed additive hopper for suppling feed additive to a rotary valve. The rotary valve meters feed additive from the hopper to a blow through assembly having an assembly inlet that receives feed additive from the rotary valve, an assembly outlet through which feed additive is dispensed, and an air port for drawing air into the assembly to facilitate feed additive dispensation through the assembly outlet. A pressurized air source delivers pressurized air to first and second feed additive delivery lines coupled to the assembly outlet, the first and second feed additive delivery lines comprising independently controllable solenoid valves coupled to a control computer of a micro weigh machine. Actuation of the solenoid valves draws feed additive from the blow through assembly and through a feed additive delivery line. A system comprising a micro weigh machine and the feed additive delivery device also is disclosed. The system is useful for batching a composition comprising an animal feed and at least one coated animal feed additive, a delicate animal feed additive, or combinations thereof. For certain disclosed method embodiments, the animals are ruminants, particularly lactating cattle, and the coated feed additive is a coated methionine product.
