“And In the cattle there is a lesson for you. We give you to drink of that which is in their bellies, from between the refuse and the blood, pure milk palatable to the drinkers.”
The Holy Quran 16:66
In quadrupeds nursing is naturally commenced just after childbirth. Actually needed ingredients for the production and secretion of milk are supplied from the digested food in the stomach which spreads out by blood. And also the lymph nodes in the breast forbid the milk’s infection by perishing its penetrated bacteria. It’s while the bloodstream and its rule in the transmission of digested foods was discovered many years after the descent of the Quran by William Harvey.
In conclusion who has been able to inform his Prophet about this issue except Allah?