So, to explain the gap between Europe and the US on farm animal welfare, we should look to the political system. In Europe, the concerns of voters about animal welfare have been effective in influencing members of national parliaments, as well as members of the European Parliament, resulting in national legislation and EU directives that respond to those concerns.
因此，要解释欧洲和美国在农场动物福利方面的差距，我们要从政治制度上寻找根源。在欧洲，选民有关动物福利的忧虑有效地影响了国家议会和欧洲议会的议员，导致国家和欧盟制定法律对此做出回应。