$('.top-carousel').on('changed.owl.carousel', function(event) {
$('.slide-title').addClass('animated fadeInDown');
setTimeout(function() { $('.slide-title').addClass('animated fadeInDown'); }, 0);
})
<input type="radio" name="slider" id="slide1" checked="">
<input type="radio" name="slider" id="slide2">
<input type="radio" name="slider" id="slide3">
<input type="radio" name="slider" id="slide4">