The Type and height of animal Will determine the type and height of post
It can be a bit daunting knowing which posts are the best to get for using with your electric fence. So hopefully this page can help you decide what posts are suitable for your field.
Firstly look at the height of the animal and also whether they are likely to stretch over a top line. For instance goats will only need a 3' fencepost as they are fairly short and are unlikely to reach over a top line whereas a pony may well be deterred by 3' electric fence but may try and reach over or jump. so depending it may be bett going for a taller post. We have customers who have quite small horses who are frightened by an electric line so will never lean over but if tempted by better grass on the other side will think nothing of jumping over for a feed.