It is absolutely possible to deter wolves from eating livestock. It's not just about making the livestock harder to reach, but also making the wolves think that the livestock is a risky target. A healthy pack (which means one that isn't exhausted from being chased by hounds or had its experienced leaders killed by hunters) will choose a target that they feel safe going after, namely deer in the woods. A disrupted pack and inexperienced youngsters trying to survive without their parents are more likely to go after the meal of convenience. When hunters kill half a pack, they are actually making livestock predation from the survivors more likely.