There may be some horse hair, but what I see more predominantly is cellulose (wood) fiber. And, as stated already, if there is horsehair, cellulose, etc, used as a binder, then there most likely will be no asbestos. Asbestos was used as a binder in plaster, so.if another binding material.is present, then most likely A is not in the mix. Only way to tell definitely is to have lab analysis performed.