I'm not so sure why people are trying to make analogies between copyright law pertaining to software and patent law pertaining to genetic material. All of these analogies seem so strained that they lose all their power.
You patent a specially engineered cow to taste good with your specially engineered steak sauce. One day your specially engineered steers jump my fence and rape my cows. Upon realizing this, I begin buying your special steak sauce from you and eating my new cows with it.
When your analogy is not about "patent law pertaining to genetic material", you wash out the absurdity.
Steers, per se, lack the (ahem, equipment) capacity to impregnate cows. I think you mean your bull jumps my fence.
Also I believe it could be argued that a specially engineered bull would rise to the level of a "dangerous animal" (such as keeping an elephant or a lion) for purposes of trespass and liability. The owner of a genetically engineered, patent-encumbered, bull would know and have prior knowledge about the unique danger involved in having such an animal escape and be held especially liable.
