Early in her career, Grandin was asked to work on a difficult problem in cattle raising. Cattle were being infested with small bugs called mites that caused a skin disease called scabies. At the time there was no vaccine to treat scabies. Instead, the cattle had to be dipped in a vat of liquid pesticide to kill the mites. However, the cattle did not like this process. They acted terrified of the vats. Some panicked so much that they drowned. A feed yard manager approached Grandin at a livestock show and asked her for help. She visited some dip vats and realized the cows feared the slippery metal slope down to the vat. Grandin started working on a design with a non-slip, concrete ramp at a gentler slope so the cattle could enter the water safely and swim calmly.

However, when the design was first tested, it did not work right: The cattle continued to panic. Grandin was at first disappointed, then realized that workers ignored her instructions and installed a slippery metal ramp. She insisted that the ramp be taken off, and then her system worked as designed. The cattle calmly and safely entered and exited the dip vats.

This system design drew more attention to Grandin, and she became sought out as a consultant.