Welll they know that something nasty is going to happen if they see a syringe, though if they previously had the worming stuff by mouth without hassle.
They also remember who was there, as evidenced by my horse turning away when YO turned up. The vet assured me they know nothing, but my horse made movements when nasty things were being done to him.
Yes my 3 year old had a cut right on his stifle when he was one and was heavily sedated to inspect it. The vet probed into it about an inch obviously causeing him pain. Its only just now i can touch the leg and pick it up. He was fine up until then he was traumatised must have really hurt him but he was heavily sedated!!! The vet was a newly qualified vet and treated him really bad (had to report her). So yes horses do remember
I'm going with no, they can't. My friend was sedated to have her wisdom teeth removed and she can't remember any of it really. She has slight, confused, non-traumatic flashbacks but in her mind it is a bit of a dream-like non-event.
Personally I think my horse moves away from the syringe because she doesn't like getting stuck by needles. She seems to have some control when she's sedated, depending on how traumatic/painful the procedure is. For example, we can get her teeth done under sedation but she needs to have her hocks and hind fetlocks injected for arthritis which is quite painful and she can bring herself round from sedation the moment she senses the vet going anywhere near her back legs with a needle. I still think she doesn't remember it though and she's still 'talking' to the vet!
I had an interesting discussion with a vet on this subject not so long ago. Apparently the practice I use are moving away from using ACP because it has been shown (how I dont know) that whilst the horse is sedated, it is still conscious, just unable to do anything about it... Not such a pleasant experience....
I also know that ACP can have an adverse effect on the liver.
I asked the vet this question when he sedated my horse to have her teeth done. They do know what is going on and the drug they give them does not make them forget, it is just sedation.
I asked this because I am a nurse and the sedation we give people for endoscopies for example does interfere with short term memory and people don't remember what they have had done.
The sedation humans have, and horses have, are not the same, so you cannot compare them. Humans are given drugs to knock us out, relax our muscles and block the memory.
I currently have a horse who is proving difficult to shoe behind, the farrier has asked that she have a full tube of sedalin before each shoeing, he maintains that after 3 x shoeings like this, she will have learned that shoeing is not bad news. I am hoping he is right...
I think they can. My mare was sedated for a thorough internal examination and for weeks afterwards she didn't want anyone anywhere near her bottom. This is a horse who had always loved having her teats and belly-button tickled by sticking your hand up between her hind legs, and the underside of her dock scratched. It didn't last forever though and she eventually realised I wasn't going to invade her privacy