[robert waddell]

the general opinion is the horses are scarred because when horses were small millions of years ago pigs hunted them if not it is a good story

[smallholder in the city]

We've only just got our pigs but my cob and shetland seem fine. The cob ignores them and the shetland seems keen to make friends. I guess that might change when the pigs get bigger. 

[waterhouse]

The pigs in question were evil-looking little black things - Vietnamese pot-bellied, i think - rather than proper pink pigs (no offence meant, not my area of interest)

The whole thing arose because the Ag college where we kept the horse at the time (15 years ago) brought them in as an experiment and installed them in some pens 10m from the main entrance to the horse yard.  OH's horse literally took one look and reared, then bolted.   There were a lot of problems with other horses, and the side entrance to the yard had to be brought into use.

OH horse is generally reliable and sensible, though we bought him as a 12yo and have no knowledge of his youth.  He reacted similarly when confronted on a local road with a driving horse pulling a cart.  And a well-known local hazard is the group of alpacas who live on a lethal bend.  But the reaction there is a spook rather than fear.  Other friends' horses have trouble with curious young cows who tend to charge over to the fence for a look. 

[nickif]

My 13.2 is fine with my Kune Kune luckily but did see a 16.2 grow to 18 hands whilst puffing like a steam train lol

[Remy]

I have a couple of pet pigs and mine are fine with them, I'm sure it would be a different matter if I didn't have any and we met them on a hack!  Horses and ponies just get used to what they live with - my horse spooks a mile if she meets a sheep on a hack - but at home, happily shares her hay with them ... 

[darkbrowneggs]

I wonder if it is that pig are omnivores and hence smell of something that eats meat, and also smells disproportionately in regard to its size

I often keep pigs but only when I need to, so a lovely cheeky little Shetland pony 8hh, who had obviously never come across pigs in his life was very perturbed by the smell in the barn, when he was in his stable. 

I thought the best thing would be an introduction ------- I wouldn't have ever imagined a "horse" of any description could have fainted, but by the time I had got him near enough to open the barn door, he was nearly on the brink of it.  Of course once he actually saw the pigs he quickly re-gained confidence.

My interpretation is that an equine has a nasal overload of something that eats meat and imagines and "enormous elephant size" predator. 

Although I feel horses and pigs may rarely become firm friends once they are properly and calmly introduced things calm down.

[Amy4]

What a brave horse you have. My boy would of legged it before they'd even got that close! Mind you he is scared of his own reflection

I think horses have a natural fear of pigs in general but some adapt to them better than others. I've known of horses living in fields near pigs with no problems.
I used to ride a TB who was fearless and the best mannered horse I've ever ridden. Never put a foot wrong. There was a field of pigs along one of our hacking routes and he would walk past it no problem but if I asked him to stand still there was no chance in hell he was stopping anywhere near the pigs! Only time he ever refused to listen to me. Think it was just his mindset that they were a predator and he had to move away from them.