This is pre-refrigeration, pre-pasteurization, and milk is an awesome growth medium for bacteria plus a direct vector to various cow born diseases. Even with refrigeration and a much better disease model, modern medicine, etc raw milk regularly kills people so historically you would expect a high lifetime risks even if people where drinking it within hours of milking it.

https://www.cdc.gov/foodsafety/rawmilk/rawmilk-outbreaks.htm...