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

BMC Veterinary Research

Table 1 The effects of dietary supplementation of NSP-degrading enzymes, LYSOFORTE^®, CreAMINO^® and their combination on the growth performance of broiler chickens:

Parameter	T1	T2	T3	T4	T5	T6	T7	SEM	P-value
Int. Wt. (g)	42.34	42.98	42.50	43.24	43.28	43.20	43.44	0.13	0.36
Starter period
BW (g)	423.65^bc	437.60^ab	415.09^c	427.31^abc	446.33^a	429.99^abc	421.60^bc	2.88	0.05
BWG (g)	381.31^bc	394.61^ab	372.58^c	384.07^abc	403.04^a	386.79^abc	378.16^bc	2.85	0.05
FI (g)	465.64^bc	488.01^ab	459.79^c	464.02^bc	496.15^a	470.47^bc	476.53^abc	3.60	0.02
FCR	1.22	1.23	1.23	1.21	1.23	1.21	1.26	0.005	0.07
Grower period
BW(g)	1073.15^bc	1112.31^ab	1034.32^c	1109.44^abc	1159.91^a	1089.62^abc	1065.89^bc	10.02	0.02
BWG (g)	649.50^bc	674.71^abc	619.23^c	682.12^ab	713.58^a	659.62^abc	644.29^bc	7.51	0.03
FI (g)	1062.82	1097.29	1037.18	1067.67	1118.65	1061.87	1073.78	9.14	0.39
FCR	1.63^ab	1.62^ab	1.67^a	1.56^c	1.57^c	1.60^bc	1.66^a	0.008	0.001
Finisher period
BW(g)	2188.32^d	2275.40^cd	2363.88^bc	2459.90^ab	2519.21^a	2491.28^ab	2275.00^cd	22.72	0.001
BWG(g)	1115.17 ^b	1163.08 ^b	1329.56 ^a	1350.46^a	1359.30^a	1401.66^a	2258.22^b	20.43	0.001
FI(g)	2256.98	2302.51	2150.40	2305.30	2365.53	2263.14	2217.22	24.97	0.34
FCR	2.03^a	1.98^a	1.63^bc	1.70^bc	1.74^bc	1.61^c	1.83^ab	0.037	0.002
Overall performance
BW(g)	2188.32^d	2275.40^cd	2363.88^bc	2459.90^ab	2519.21^a	2491.28^ab	2275.00^cd	22.72	0.001
BWG(g)	2145.98^d	2232.41^cd	2321.38^bc	2416.66^ab	2475.93^a	2448.08^ab	2231.56^cd	22.70	0.001
FI(g)	3785.45	3853.36	3707.48	3806.50	3980.34	3795.49	3767.54	34.65	0.47
FCR	1.76^a	1.72^a	1.60^bc	1.57^c	1.60^bc	1.55 ^c	1.68^ab	0.01	0.001
RGR	192.40^c	192.58^bc	192.92^ab	193.08^a	193.24^a	193.18^a	192.50^bc	0.06	0.001

^a,b,c,d Means within the same row carrying different superscripts are significantly different at (P < 0.05).
T1: Control group "basal diet with no additives (breeder recommendation (BR)). T2: Basal diet minus 100 kcal/kg supplemented with 0.02% NSP-degrading enzymes (NSP). T3: Basal diet minus 50 kcal/kg supplemented with 0.025% emulsifier (LYSOFORTE^®). T4: Basal diet minus 50 kcal/kg supplemented with 0.06% guanidinoacetic acid (CreAMINO^®). T5: Basal diet minus 150 kcal/kg supplemented with a mixture of NSP and LYSOFORTE^® (NSPL), T6: Basal diet minus 100 kcal/kg supplemented with a mixture of NSP and CreAMINO^® (NSPC). T7: Basal diet minus 200 kcal/kg supplemented with a mixture of NSP, LYSO, and CreAMINO^® (NSPLC)..
BW body weight; BWG body weight gain; FI feed intake; FCR feed conversion ratio; RGR relative growth rate