Helping straw break down in a hazelip-style garden

What's the best way to get straw to break down faster on Hazelip-style straw-covered beds? I've had mine covered for 5 months now in barley straw (am in the UK, so over a warm summer) and there doesn't seem to be much movement. Presumably due to not enough nitrogen?

I'm reading the One Straw Revolution at the moment, and I noted that Fukuoka talks about putting chicken manure on his straw to help it rot. The chicken manure I can find is pelleted. Will that do?