Why does a piglet tremble while sleeping?

The piglet trembles while sleeping, eating, normal. Pooping, normal. What is the reason?
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It should be low ambient temperature.
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Right! It should be low ambient temperature! Just like people, trembling is also a way to guard against the cold!
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Maybe it's talking in its sleep?
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Low ambient temperature, talking in sleep, or abdominal pain are all possible
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It's probably congenital; it's more obvious right after birth, maybe it's just not adapting to the outside world
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Maybe it's talking in its sleep?
Rover in the Mountains posted on 2009-5-19 00:32

What an extraordinary imagination!!!!
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Could it be dreaming!
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Hehe, how can the person above have such a high imagination?
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When you're cold while sleeping, you tremble too, hehe!!!!
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It might be dreaming!!!!
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Maybe it's flies causing trouble.