Therefore the devotional service of the Lord with perfect knowledge through the training of a bona fide spiritual master is advised for everyone, even if one happens not to be a human being. This is confirmed in the Garuda
Purana as follows:
kita-paksi-mrganam ca
harau sannyasta-cetasam
urdhvam eva gatim manye
kim punar jnaninam nrnam
"Even the worms, birds and beasts are assured of elevation to the highest perfectional life if they are completely surrendered to the transcendental loving service of the Lord, so what to speak of the philosophers amongst the human beings?"

(From Srila Prabhupada's purport to SB 2.9.36)