(A member of the audience asked and question and it was audible)
The horse was not being scarified. Do you know what Ashwa means? Shwa means for yesterday and tomorrow. Ashwa means atma which means self purification. So what were they doing for self purification? They used to let loose a chosen horse free to roam about and whatever ground he walked on was considered purified. Therefore it is nowhere mentioned that the horse used in the Ashwamehda Yagna was sacrificed. All this was imagination of people.