Here are some things to consider:
* Prey Drive: Even the most well-behaved dog can have an instinctual reaction to chase small animals.
* Size Difference: A Shih Tzu could easily injure or even kill a guinea pig accidentally.
* Safety: Guinea pigs are delicate creatures and can be easily frightened by a dog, leading to stress and health issues.
Instead of leaving them unsupervised, it's best to supervise all interactions between your Shih Tzu and guinea pig. This includes:
* Introducing them slowly: Let them sniff each other through a barrier, then gradually increase their interactions.
* Positive reinforcement: Reward your Shih Tzu for calm behavior around the guinea pig.
* Never leaving them alone: Always supervise their interactions to ensure the guinea pig's safety.
Remember: Even if your Shih Tzu seems friendly and gentle, it's crucial to prioritize the safety of your guinea pig.