Someone in my Twitter feed said today:
TIL starbucks put ground up insects in stuff, and milk has blood in it.
The ground up insects part is true for now, but I'm not sure about the blood-in-milk one. It sounds half-way plausible, considering that breastfeeding mothers can sometimes suffer bleeding.
A more specific example of the claim, from notmilk.com:
Also, all cows' milk contains blood! The inspectors are simply asked to keep it under certain limits. You may be horrified to learn that the USDA allows milk to contain from one to one and a half million white blood cells per millilitre. (That's only 1/30 of an ounce). If you don't already know this, I'm sorry to tell you that another way to describe white cells where they don't belong would be to call them pus cells.
Snopes says (no links due to its dodgy advertising) that the blood in milk (specifically, blood in chocolate milk) is false, but doesn't provide any specific references. Most of the other top Google hits for
cow's blood milk are for anti-milk sites, user-generated content, or pages unrelated to this topic.
For convenience, assume that the claim is about the processed and government-approved milk that people in the USA drink, not what immediately comes from the cow.