Luckily, there are exceptions to this nonsensical practice and some trespassers are spared the tragic outcome.
Penka, the unlucky cow who put her life on the line by crossing the EU border and was sentenced to be put down, will live on after Bulgarian authorities said she posed no health danger.
"Laboratory analyses of the cow, that spent 15 days in Serbia and crossed the border back (into Bulgaria) are negative for all the tested diseases," Bulgaria's Food Safety Agency announced on Monday.
"She will not be killed and will return to her herd by the end of the week," agency spokeswoman Ekaterina Stoilova told AFP.
Penka’s predicament quickly made international headlines and invited a huge outpouring of sympathy after her owner went to social media with an appeal to save the poor bovine.
Calling her "the most famous Bulgarian woman,"Penka's fans, shared her story and even wrote a poem about her.
On May 12, Penka, only three weeks away from giving birth, wandered away from her herd in Bulgaria and strayed into the country’s non-EU neighbor, Serbia.
The four-legged trespasser was later returned to her Bulgarian owner but even though Serbian veterinarians had given her a clean bill of health, Bulgarian officials said the cow would have to be put down due to the EU’s no-nonsense health rules.
According to European Commission guidelines, cows must be presented at border checkpoints with documents verifying they are healthy.