Well the common denominator to every animals run is its elapsed Time.
But you need a standard to compare it against.

You could use the Race Record for the Track and Distance.
A better method is to use the Average.
Another could be to average the past 200 races.
Another could be to average the top 10 times.
Another could average only races of todays Grade.

I have my own suck it and see standards which i choose not to divulge , they prolly wrong anyway.

Are you using a Time standard raven , and if you are , what are you using?