Remember you need high-carbon material (which straw or shavings is) along with high-nitrogen material (that would be the chicken-poo - it's pretty low in carbon) in order to get effective composting.
If you are wanting the poo to mix in with other carbonaceous material you have in a compost pile, consider building a droppings board under the roost to collect each night's droppings, which will be somethinglike 50% of they daily output. Scrape it off each morning into a bucket to take to the compost. Use something like that plasticky-covered particleboard stuff that cheap shelves are made of, or use a board covered in a vinyl flooring scrap, to make it easy to scrape clean.
Most people, tho, just wait til all the litter is good 'n' pooey and compost the whole enchilada. It may end up a little more tilted towards the carbon (rather than nitrogen) side of the equation and take a little longer to compost than if you had the optimal ratio but it does work pretty well.
Good luck,
Pat