保护动物的海报可以包含以下五句英文宣传语：

1. Protect animals, treat creatures kindly.

2. Love animals, love the world.

3. Preserve the ecological balance.

4. Every creature has its place, protect it.

5. Join hands to safeguard wildlife.

这些宣传语强调了保护动物的重要性，并鼓励人们采取行动维护生态平衡和地球家园