"Ladies and gentlemen,
This is the captain speaking. I apologise for the sudden deceleration but we are not taking off at this moment. Unfortunately a rather large pig decided to cross the runway and put itself in our path, and it appeara we have hit.
If we manage to stop before running off the end of the runway into the lagoon, we will return to stand, survey the possible damage to the aircraft, and be off agiain in a few more minutes."
RTO succesful, return to stand. Passengers not allowed off. Forward pax door opened. Different sort of smell in the air. FO sent to inspect undercarriage, engine intakes.
Fire engine appears, directs hose at nose undercarriage, then nose, then (after closing port pax door) foward fuselage, both sides, inner halves of wings, main U/C. Pig guts slide down hull past forward windows as the fire engine hose works its way over the fuselage.
FO returns, a shade or two paler and after a detour to the tower toilet. Fire up again (WhooshWhump, whooshWhump, it's a 1-11).
"Ladies and gentlemen, we do offer our apologies for the delay. We are now departing the stand and expect to be en route to xxxxx within six minutes. On behalf of YYYY airlines I hope you have enjoyed your stay in this exotic corner of our country and we hope that you will come again".
No, of course the dialogue didn't happen. The event did, though, and it was a minor one amongst many at a fairly remote outpost; I just happened to be the airline's agent and on board at the time.