I currently use some bedded pack cattle manure on a few acres. I also run another farm that used to get quite a bit of pig and cattle manure, but the livestock have been gone for about 12 years. Soil test are still really high in P and K. I really dont have enough acres covered with manure each year to worry about how much N I am getting from it. You can get manure sampled to check the N content though. I have been trying to get some chicken shit for a couple years, but we have quite a few organic guys around that they give preference to. Its usually all gone by the time they could get to a small grower like me. They just recently built 7 HUGE barns a few miles from where I farm so it might get a little easier to get some.
If I can get my hands on it either this fall or next spring I would send a sample of the manure off and figure my N needs off that. My neighbor is raising organic corn and soybeans and has been using pelletized poo, but the drawback is the cost. Its working good for him. You can burn seed/roots with manure. I think its most likely to happen with hog manure from a finisher barn with few water leaks, followed by a high rate of chicken shit. Burning is most likely to happen on coarse textured soils (sand/ gravel types). Pretty tough to burn the seed in our heavy, fine-textured soil with cattle manure. My goal for my corn ground next year is to get 5 tons of chicken litter per acre. It smells awful.