Manchester airport and its owner Manchester Airports Group, which includes Stansted and East Midlands airports, declined to comment, saying it was a commercial matter. However, TTG understands such ads at Manchester have previously been refused because of perceived conflicts of interest. Back in March, easyJet holidays said it would no longer offer zoos and marine parks as part of a wide-ranging new animal welfare policy. A fortnight later, Jet2holidays followed suit, leaving Tui alone among the UK’s three main operators continuing to sell attractions with captive cetaceans. WDC claimed Tui’s…