Background:
9 working sheep dogs (collies and huntaways)
1 pet dog
All of them are very well behaved we compete and put A LOT of effort into training.
Anyhow! One of our working dogs is constantly slipping his collar unless it is on so tight that we can't slip a finger under. this is obviously not a good idea even though it's not choking him it's surely not uncomfortable for him. He doesn't run away or anything naughty but we often have bitches on heat etc
What type of collar can you reccomend? It has to be a collar and not a harness as he needs to be able to be clipped to the fence during musters he isn't taking part in.
Thanks!