I don't spin and I don't do one day mail and I send it flat rate. I pull blood, or colostrum, wrap each one in bubble wrap, wrap all them in bubble wrap, cut pieces of syrofoam to fit the flat rate box, put the bubble wrapped colostrum in the middle and put in hard iced containers from wallmart. More styrofoam pieces. I put a key (goat A is Shoofly, goat B is blah blah, my name addy, customer number and send it $8.95. I have never had blood, colostrum or milk samples come back as too warm to process. But it's also why I use people friendly labs

When using WSU for blood, my vet sends it in. Vicki