Question Range for animals finding the SF feeder and eating

Is there a range for animals (such as horses) for eating from the SF Feeder? We have some that get hungry and thirsty when they appear relatively close to the feeder.

In animal versions below 4.0 it is the their walk range. For version 4 onwards it's now twice that value. Note that for the SF Feeder (grass) it's the centre of the water container that is the the reference point.

Also I have noticed that sometimes animals do stop feeding when close to a feeder but this can be sorted by giving them a loving 'Pet'