It is a common misconception held by many that Noah’s ark had to hold every kind of cow, and every kind of horse, and every kind of all the other animals, in which case it would have had to be truly, incredibly, mind-bogglingly enormous!!! But this was just not so!
To get some idea of the capacity of the ark, it could hold 125,280 sheep! Now considering the average size of most animals, which is about the size of a sheep, it is obvious that there was plenty of room for all the animals.
But what people forget is that from one breeding pair we can get a lot of different varieties. For example the dog. From one breeding pair of dogs we can get everything from Chihuahuas to Great Danes.
From one breeding pair of horses we can get everything from Arabs to draft. From two cats we can get Persians, Manx and tortoiseshell through to Siamese. All Noah had to take on board was one breeding pair of each basic kind, or gene pool, from which all the varieties we have today could come after the flood.
As usual the difficulties disappear when we apply a little common sense to what the Bible says.

The Bible says; ‘Forty years long was I grieved with this generation, and said, It is a people that do err in their heart, and they have not known my ways.” Psalm 95:10 (King James version)