What the Standards say about the origins of livestock
Section 205.236 of the NOP Standards states that to be sold as organic, an animal must be managed organically for its entire life plus a third of its time in the womb. Special circumstances apply for poultry, breeder stock and dairy animals, as follows:
• Poultry must be managed organically from the second day of life.
• Breeder stock "may be brought from a non-organic operation onto an organic operation at any time" (§205.236(a)(3)). Bulls, rams, billy goats, etc., do not need to be managed organically. Of course, if you buy a non- organic pregnant ewe and you want to sell its offspring as organic, you must bring the ewe to the farm prior to the last third of gestation, and you must manage it organically from then on.
• Dairy animals must be managed organically for a full year prior to the sale of any milk or milk products as organic. Once a farm's entire herd has been converted to organic, all dairy animals on the farm must be managed organically from the last third of gestation. (In other words, it's not okay to move your organic heifer calves to non-organic feed for the first part of their young lives, then shift them back to organic feed one year prior to their first lactation.)
Once they've transitioned, some organic farmers seek to keep a closed herd in order to minimize the possibility of introducing disease organisms with new stock. Note that artificial insemination (AI) is allowed under organic standards, but the use of hormones to regulate breeding cycles is not.