▁in ▁Oak land , ▁California , ▁the ▁department ▁of ▁public ▁health ▁and ▁safety ▁issued ▁an ▁order ▁to ▁" put ▁your ▁ro ost ers ▁in ▁a ▁light [- ] proof ▁co op , ▁or ▁dev ise ▁appar atus ▁that ▁will ▁hold ▁the ▁ro oster ' s ▁head ▁down ▁so ▁he ▁can ' t ▁crow " ▁in ▁response ▁to ▁compla ints ▁about ▁the ▁noise ▁they ▁were ▁making . ▁ ▁Od or ▁Od or ▁concerns ▁can ▁be ▁mit ig ated ▁somewhat ▁by ▁limit ing ▁the ▁number ▁of ▁ch ick ens ▁that ▁a ▁household ▁can ▁own . ▁Un like ▁large ▁commercial ▁operations , ▁where ▁thousands ▁of ▁ch ick ens ▁are ▁kept ▁in ▁close ▁qu arters ▁and ▁thus ▁build ▁up ▁enough ▁am mon ia ▁to ▁create ▁a ▁powerful ▁od or , ▁small ▁back yard ▁operations ▁produce ▁proportion ately ▁less ▁od or . ▁Although ▁in ▁urban ▁spaces ▁where ▁homes ▁are ▁situated ▁right ▁beside ▁one ▁another , ▁steps ▁must ▁be ▁taken ▁to ▁control ▁od ors . ▁These ▁range ▁from ▁regular ▁clean ing ▁to ▁changing ▁out ▁the ▁ch icken ' s ▁bed ding . ▁If ▁not ▁properly ▁c ared ▁for , ▁od ors ▁can ▁become ▁quite ▁strong ▁given ▁close ▁proxim ity ▁to ▁neighbor ing ▁homes . ▁The ▁average ▁ch icken ▁elimin ates ▁waste , ▁on ▁average , ▁every ▁fifteen ▁to ▁twenty ▁minutes ; ▁a ▁co op ▁of ▁nine ▁ch ick ens ▁will ▁produce ▁approximately ▁seven ▁hundred ▁( 7 0 0 ) ▁def ec ations ▁per ▁day . ▁ ▁Un w anted ▁pred ators , ▁p ests , ▁and ▁rod ents ▁Pred