▁d eter ▁attacks ▁on ▁the ▁sheep ▁during ▁the ▁experiments . ▁Sho cks ▁( 3 0 0 0 V , ▁ 0 . 4 A , ▁duration ▁ 1 ▁second ) ▁were ▁delivered ▁when ▁dogs ▁came ▁within ▁a ▁distance ▁of ▁ 1 - 2 m ▁of ▁the ▁sheep , ▁and ▁were ▁repeated ▁until ▁the ▁dogs ▁left ▁the ▁area . ▁The ▁objective ▁was ▁to ▁suppress ▁an ▁attack , ▁but ▁not ▁to ▁damage ▁the ▁hunting ▁ability ▁of ▁the ▁dogs . ▁Despite ▁frequently ▁initi ated ▁ch ases ▁and ▁attacks , ▁few ▁shock s ▁were ▁delivered . ▁This ▁was ▁because ▁few ▁dogs ▁approached ▁closer ▁than ▁ 1 – 2 ▁m , ▁and ▁the ▁intention ▁was ▁to ▁d eter ▁proxim ity ▁to ▁sheep ▁rather ▁than ▁to ▁associate ▁hunting ▁behaviour ▁with ▁an ▁a vers ive ▁shock , ▁which ▁would ▁imp air ▁future ▁hunting ▁behaviour ▁in ▁other ▁context s . ▁ ▁Christians en ▁et ▁al . ▁study ▁( 2 0 0 1 b ) ▁The ▁dogs ▁used ▁in ▁the ▁first ▁study ▁were ▁re - test ed ▁using ▁the ▁same ▁procedures , ▁to ▁assess ▁long - term ▁impact ▁of ▁the ▁training ▁on ▁their ▁reaction ▁to ▁sheep . ▁Again , ▁in ▁the ▁free - running ▁tests ▁the ▁dogs ▁were ▁fitted ▁with ▁a ▁shock ▁col lar , ▁which ▁was ▁used ▁to ▁d eter ▁approaches ▁to ▁within ▁ 1 - 2 m ▁of ▁the ▁sheep . ▁D ogs ▁that ▁had ▁previously ▁been ▁shock ed ▁in ▁year ▁ 1 ▁showed ▁a ▁significant ▁increased ▁in ▁laten cy ▁to ▁approach ▁a ▁person ▁during ▁the ▁path ▁test ▁( p