Are the energy matrix values of the different feed additives in broiler chicken diets could be summed?

BACKGROUND: The aim of this study is to investigate whether the energy matrix values of the nonstarch polysaccharide- (NSP-) degrading enzymes, bioemulsifier (LYSOFORTE(®)), guanidinoacetic acid (CreAMINO(®)), or their combinations could be summed. The effects of these additives on the growth performance, carcass traits, and economic value of the broiler chicken diets were evaluated. A total of 525-one-day-old Ross chicks with an initial body weight of 42.96 ± 0.87 g were haphazardly allocated into seven groups with five replicates. The seven experimental treatments are as follows: (1) basal diet with no additives (breeder recommendation), which is the control group, (2) basal diet minus 100 kcal/kg supplemented with 0.02% NSP-degrading enzymes (NSP), (3) basal diet minus 50 kcal/kg supplemented with 0.025% emulsifier (LYSOFORTE(®)), (4) basal diet minus 50 kcal/kg supplemented with 0.06% guanidinoacetic acid (CreAMINO(®)), (5) basal diet minus 150 kcal/kg supplemented with a mixture of NSP and LYSOFORTE(®) (NSPL), (6) basal diet minus 100 kcal/kg supplemented with a mixture of NSP and CreAMINO(®) (NSPC), and (7) basal diet minus 200 kcal/kg supplemented with a mixture of NSP, LYSO, and CreAMINO(®) (NSPLC). The experiment lasted for 35 days. RESULTS: It was found that the final body weight, body weight gain, and relative growth rate were significantly higher in birds fed diets supplemented with NSPL, NSPC, CreAMINO, and LYSO with the reduced energy matrix value. The overall feed conversion ratio was significantly improved due to the supplementation of NSPC, CreAMINO, NSPL, and LYSO with the reduced energy matrix value compared to the control group. Moreover, no significant effect on the carcass criteria was observed by the different treatments. As a result of the dietary supplementation with NSPL, NSPC, CreAMINO(®), and LYSO with the reduced energy matrix value, the net profit, total return, economic efficiency, and performance index were increased and the cost of feed per kg of body weight gain was decreased. CONCLUSION: The energy matrix value of NSPL, NSPC, CreAMINO(®), and LYSOFORTE could be established in the diets of broiler chickens to improve the growth performance and economic efficiency.