If you study Eschatology carefully, you'll find that Jesus descends to the mount of Olives before anything else. These white horses are mounted afterward, then the armies of heaven and Jesus comes to the valley of Jehoshaphat for Armageddon.
In addition to that. Animals expire, it says so in psalm 104. They are not body soul and spirit like we are, otherwise they would be made in the image of God too. Only humans are made in God's image.
Yes, there will be animals in heaven, just not the ones from this earth.