It is said that animal state of consciousness is like a mirror, which is covered by dust. So in a mirror that is covered by dust, one cannot get a clear picture at all. At best one may see some contours - a shadow. We can still see some dark form of shadow, otherwise you can’t see anything - the mirror is totally covered by dust. So the animals’ consciousness is like that. The animal cannot see clearly – cannot see the Supreme Lord clearly.
Therefore, the animal practically has no chance! No chance to engage in devotional service, so there is a very precarious condition. The only way that the animal can engage in devotional service is through the arrangement of the human being.
Normally the human being engages in the worship of the Lord and can engage the animals also: Elephants carry deities, animals take prasadam and so in that way animals can certainly partake in devotional service. They can hear kirtan and there are various ways that they can engage in service but always in connection with the mercy of the human being.
Kadamba Kanana Swami, Canberra, October 2010)