Vetoquinol Zylkene Equine Behavior Support Horse Supplement Powder 2000mg, 20ct

Q: Can you use this just once for a stressful event, or do you have to use it several days in advance? I'm thinking just for a horse who is hard to load

I think the product is intended for longer term use. I did not find it helped my horse who was having trouble adjusting to a new stable after a move. I finally just moved him somewhere else.

Q: If it takes 3 days to become effective, How long do the effects last?

Maybe a day or 2 after coming off of steady state dosing, depending on the root cause of your horse's anxiety, and stimuli in the environment.

Q: How many pouches come in this?

20 pouches - depending on your horse's weight, you need 1 to 2 pouches per day. I don't remember exact cutoff, but I think it was 1 pouch up to 1,250 lbs, 2 pouches if over that. By the way, I was extremely pleased with the results!

Q: Can you use this at an open/4h type show or would they test + for something?

There are not usually any blood tests pulled at Open or 4H shows. Only approved higher level shows regularly test for drugs. With that being said, I do not know if the tryptophan will show up as a prohibited substance. You would do well to check with whichever governing body disapproving the show to see if there are any prohibitions.