Cow blowing, per Wikipedia:
Kuhblasen, phooka, or doom dev, is a process used in many countries according to ethnographers, in which forceful blowing of air into a cow's vagina (or sometimes anus) is applied to induce her to produce more milk.
Cow blowing was the reason why Gandhi abjured cow milk, saying that "since I had come to know that the cow and the buffalo were subjected to the process of phooka, I had conceived a strong disgust for milk."
There is, of course, a video that shows how it's done - for those with delicate sensibilities (and if this is true of you, what the hell are you doing here?) it's below the break.
Previously in the "disgusting things having to do with cattle" department, there's this:
Urine-drinking Hindu cult believes a warm cup before sunrise straight from virgin cow cures cancer, baldness.
