>>>  The first time dairy cows are impregnated is at 13-15 months of age, so that they give birth and first start producing milk at about 20 - 24 months of age (http://animsci.agrenv.mcgill.ca/courses/450/topics/6.pdf ).  From then on, the most common standard is that all cows are impregnated 70 to 90 days after each time they give birth with the ( Read more... )