I might equally wonder if you are being serious in weighing anecdotal evidence against a huge body of failed research trials that consistently demonstrate no impact beyond placebo (in humans, and apparently in animals as well); while any trial that might appear to support homeopathy as an effective treatment almost invariably has a flawed methodology, or skewed data.
As to whether or not there exists a placebo effect in animals -- I believe the answer is as yet unknown, but it is a misconception that "having no idea what you are being given" negates the possibility of placebo. Moreover there is anyway the problem of separating the animal's actual response to the treatment from a human's perception of it -- just as you can't persuade a dog that a sugar pill is more than sugar, you can't really ask how it feels afterwards. Animals have a tendency sometimes to appear deceptively fine one moment and dead virtually the next, for that matter -- or even vice versa, carrying horrific injuries and apparently ignoring them.
No, there is no evidence beyond hearsay and anecdote to support homeopathy as an effective, active treatment in humans or animals. Whether there exists an active placebo effect in animals (or, alternatively, a "proxy placebo"/ conditioning effect), is an active area of debate. The efficacy of homeopathy is not.
"The assumption ... is that any effect in a baby or animal cannot be due to the placebo effect, because placebo effects are dependent upon the expectation of benefit. This is a gross misconception, however. Placebo effects can result from the attention of the caregiver or other non-specific effects. Or they can simply be an artifact of observation – the person observing for an effect in the animal or baby may be the one responding to the placebo... there is no good evidence for the effectively [sic] of any homeopathic remedy in any population."
(from sciencebasedmedicine.org, 2010)