Why consider the use of Shock Collars (E-Stimulus, E-Touch) carefully

Why consider the use of Shock Collars (E-Stimulus, E-Touch) carefully This is a bit technical but brief overview on this issue. I will do my best to make it easy for everyone to understand. In the JVB (2007) Overall evaluated the molecular and cellular use of shock on the learning process. She suggested, "we may be changing other behaviors or processes” with these collars technically called E-Stimulus Devices. Overall (2007) uses what she describes as “a landmark study” by Schilder and van der Borg published in Applied Animal Behavior (2004). Schilder and van der Borg noticed dogs exhibiting more stress related behavior when using these types of devices. Stress related behavior continued with the control group, during free time in the handlers presence while at parks, when dogs should be relaxed. Stress behaviors and/or conflict resolution behaviors is extensively defined in recent dog literature.