Answer: Rabbit damage would consist of symptoms such as chewed off foliage and chewed bark/trunk damage. If the trunk is badly damaged the plant will not survive. To protect against rabbits you would need to put a wire mesh cylinder around the plant; it should reach upward to two feet above the expected snow line and also spread outward at ground level to deter them from digging in under it. There are also spray on repellents sold at garden centers that you could try.
However, based on your description, I am not certain what you are seeing is signs of rabbit damage. It might be drying out caused by a rooting problem underground, for instance if the roots have not spread out into the surrounding soil, or if the soil was kept too dry or too wet.
I would suggest you work with your county extension and/or the retailer where you purchased the plants to try to determine what is causing the problem and based on knowing that, determine how to proceed. I'm sorry you are having trouble with your shrubs.
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