Nó bị tịch thu và nuôi nhốt.

Nó most likely means it in this sentence.

A few important notes:

• For animals or objects, nó is very common.
• For people, nó can sound rude, dismissive, or only natural in certain close-family situations when talking about a child.
• Because the sentence uses tịch thu and nuôi nhốt, the thing being talked about is probably an animal or possibly something treated like property in the context.

So in this sentence, a learner should usually understand nó as it.

Bị marks that the subject is undergoing something, often something negative, unwanted, or harmful.

So:

• bị tịch thu = to be confiscated / seized
• bị nuôi nhốt = to be kept in captivity / caged

This is one of the most common ways Vietnamese expresses a passive-like idea, especially when the event is bad for the subject.

A very useful comparison is:

• bị → something bad or unfavorable happens
• được → something good or favorable happens

Since being confiscated and confined are negative, bị is the natural choice.

Vietnamese usually does not need a separate word like English was.

Instead, Vietnamese often relies on:

• context
• time words
• particles such as đã, đang, sẽ

So Nó bị tịch thu và nuôi nhốt can mean:

• It was confiscated and kept in captivity
• It is being confiscated and kept in captivity
• or something similar, depending on context

If you want to make the past clearer, you could say:

• Nó đã bị tịch thu và nuôi nhốt.

That makes the past meaning more explicit.

Tịch thu means to confiscate, to seize officially, or to take away by authority.

It is stronger and more official than just take. It often suggests:

• police
• customs
• forest rangers
• government authorities
• school staff or other authority figures

For example:

• Cảnh sát tịch thu hàng lậu.
  The police confiscated the smuggled goods.

In your sentence, bị tịch thu means the subject was seized/confiscated, probably by some authority.

Yes, but usually only in certain contexts.

It sounds natural when talking about:

• wild animals
• illegally kept pets
• animals seized by authorities

For example, if someone illegally keeps a monkey or rare bird, Vietnamese can say the animal was bị tịch thu.

It would not normally be used for a human being. So this sentence strongly suggests that nó is probably an animal, not a person.

Nuôi nhốt means something like to keep in captivity, to keep caged, or to confine and raise/keep an animal.

It combines two ideas:

• nuôi = to raise, feed, keep
• nhốt = to shut in, cage, confine

Together, nuôi nhốt usually suggests that an animal is being kept enclosed rather than living freely.

This is more specific than just nuôi:

• nuôi chó = raise/keep a dog
• nuôi nhốt động vật hoang dã = keep wild animals in captivity

So in your sentence, the meaning is not just that it was cared for, but that it was kept confined.

Because bị can apply to both verbs at once.

So:

• Nó bị tịch thu và nuôi nhốt.

means:

• It was confiscated and kept in captivity.

Vietnamese often avoids repeating words when the meaning is already clear. Here, bị covers both tịch thu and nuôi nhốt.

You could repeat it:

• Nó bị tịch thu và bị nuôi nhốt.

But that is usually less smooth unless you want extra emphasis.

Normally, no.

Được usually suggests something beneficial, lucky, or welcome. For example:

• được khen = to be praised
• được giúp đỡ = to be helped

But in your sentence, the events are negative:

• confiscated
• confined

So bị is the correct and natural choice.

Using được here would sound wrong unless the speaker had some very unusual perspective and considered those actions beneficial.

Yes, it is natural, but it suggests a fairly specific context.

It sounds most natural in situations like:

• an illegally kept wild animal was seized
• an animal was taken by authorities
• an animal ended up in captivity after being confiscated

So the sentence gives a strong hint that:

• nó is probably an animal
• the speaker views the situation negatively
• the agent is not important or is already known from context

For a human being, this sentence would sound very odd because tịch thu is not normally used for people.

You can add the agent right after bị or before the verb phrase, depending on how you build the sentence.

For example:

• Nó bị kiểm lâm tịch thu và nuôi nhốt.
  It was confiscated and kept in captivity by the forest rangers.

• Nó bị cơ quan chức năng tịch thu.
  It was confiscated by the authorities.

In everyday Vietnamese, people often leave the agent out if it is obvious or unimportant. That is why the original sentence sounds perfectly normal without saying who did it.