Of course every day is a a cat day, but there are specific dates in several countries. I remember when the Festa del gatto or Giornata del gatto was proclaimed in Italy, as I was studying there for part of that year (and during some years before).
https://it.wikipedia.org/wiki/Festa_del_gatto on the 17th of February. There are artistic events and of course adoptions of the many stray cats living amidst ruins and ancient walls in Italian towns.
World or International Cat Day takes place on August 8th, so we must keep that in mind!
This rather arch article contests the very surfeit of world or national “days”. While I agree that many of them are obvious advertising ventures (often for junk food), there can never be too many days devoted to animal welfare or protecting nature, and certainly not to our dear moggies and their wild cousins.
http://www.vogue.it/en/people-are-talking-about/that-s-too-much/2012/04/world-cat-day
World Animal Day is the Feast of St Francis, but is celebrated far beyond Catholics and other Christians. Many Buddhists travel to visit Assisi, for example.
The list omits World Toilet Day (October 19th) which sounds like an excuse for loo humour, but it actually highlights the lack of facilities in many countries and for such groups as women (including pregnant women) and disabled people. It does involve jokes, as a way of talking about an important but malodorous topic.
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