Question
Can animals attain moksha?
Answer
No, animals don't attain moksha. Because the natural order is as below:
sthāvarāḥ krimayo'vjāśca pakṣiṇaḥ paśavo narāḥ
dārmmakāstridaśāstadūnamokṣiṇaśca yathākramam [VP - 2.6.34]Meaning
After experiencing the sufferings of hell, the sinners go through the various stages of existence in the following order: immovable trees, worms, birds, animals, men, pious men, gods and liberated souls.
Moreover, if by moksha you mean, the advaita one, then by no means animals can attain that because they cannot cultivate the knowledge to ward away ignorance.
However, due to the grace of the Lord an animal certainly can attain mukti, just like Gajendra did [SB - 8.4.6]. But these are special cases when they were devotees of Lord in their previous births. For example, Gajendra was a devotee of the Lord:
This Gajendra had formerly been a Vaiṣṇava and the king of the country known as Pāṇḍya, which is in the province of Draviḍa [South India]. In his previous life, he was known as Indradyumna Mahārāja. [SB - 8.4.7]
Other than that, I have also heard that god-realized saints can also liberate animals if they want. But in anyway, animals can't attain moksha naturally by their own, because unlike humans, those are bhoga yonis (where one only experiences the deeds of his actions, doesn't accumulate newer ones).
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