It is with or without collars. The collars are there for the people to know which ewes to keep and which ones to get rid of.
Yes, the livestock readily sense the attitude of the dogs (in control, not in control, confident, hesitant, calm, anxious, etc) and the dogs sense the attitude of the sheep (nervous, calm, followers, leaders, wanting to challenge, etc). This interaction between dog and livestock intrigues me and I strive to capture in photos.
Also the interaction between the individual livestock impacts how the group of livestock must be managed. Like any group of individuals there are those that really want to be together, those that don't care, those that don't want to be together, those that get roudy when together, those that stay calm when together, etc. Once you start splitting off sheep from the group you'll often find there is one or more that really want to be with those you split off; requiring more effort to keep the remaining sheep together. Occasionally you'll get a group where there are two that really don't want to be with each other. Years ago I watched a run where two ewes spent the entire run moving away from the dog to stopping and head butting each other, and then moving away from the dog.
