<P><B>Abstract</B></P> <P>The purpose of this study was to examine if the energetic potentials of chicken manure can be used more efficiently in the biogas process by means of pre-treatment with pressure swing conditioning (PSC). Two sub-questions were of interest: the effect of pre-treatment on the nitrogen content in the manure and the effect of pre-treatment on the methane yield. Six variants of PSC were examined concerning nitrogen content and methane yield in batch tests. PSC-variant 150 °C/5 min showed an increase methane yield of 14.4% (to 288 mL/gVS) in best case compared to the untreated reference. The result's kinetic model analysis indicate faster degradation rates. PSC-treatment caused a reduction of the total ammonia nitrogen content of 39% on average of the six variants (via gas phase). One PSC-variant and untreated chicken manure were chosen for continuous fermentation tests in continuous stirred tank reactors in lab-scale. In the continuous test a methane production of 294 mL/g VS for untreated manure was observed and of 297 mL/g VS for PSC-chicken-manure (150 °C/5 min). With the right parameter set, PSC is able to enhance the degradation speed and to decrease the total ammonia nitrogen content of chicken manure with straw pellets as bedding material.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Up to 57.2% nitrogen reduction in chicken manure via pressure swing conditioning. </LI> <LI> Increase of 14.4% of methane yield through pressure swing conditioning in best case. </LI> <LI> Response surface method graphs of treatment (time, temperature) and methane yield. </LI> <LI> Comparison between batch and continuous biogas tests (each in 3 parallels). </LI> <LI> Similar biogas yields in continuous biogas tests for un-/pre-treated chicken manure. </LI> </UL> </P>