“The cow is milked from her head”–the food that is put under a cow’s head determines the amount of milk she will give. Metaphorically speaking, getting a good story (or milking) from someone by offering good food.
“It went where it was needed.” In Ireland, it is believed that if a cow kicked over the milking can and spilled the milk, it was because the fairies wanted a drink.
“The day will come when the cow will have use for her tail”–there are better days ahead.
