A while ago, a man was arrested for trying to ship a live alligator through the United States Postal System - simply packing it in a cardboard box. The reason he was charged? The USPS does not allow customers to ship live alligators which exceed two feet in length.
I'm now realizing that this comic might not make sense if you don't know that shepherds will use the process described above to track sheep mating patterns. I just assumed everyone else spent their Saturday nights looking up ungulate husbandry on the internet too.