. 2021 Sep 21;100(12):101495. doi: 10.1016/j.psj.2021.101495

Table 8.

Carcass characteristics of broilers fed diets with increased nutrient density and/or phytase supplementation from 1 to 41 D of age, Experiment 2¹.

			Carcass		Total breast		Wing		Drum		Thigh		Abdominal fat
Treatment	Nutrient density²	Phytase, FTU/kg³	Weight, g	Yield, %⁴	Weight, g	Yield, %⁴	Weight, g	Yield, %⁴	Weight, g	Yield, %⁴	Weight, g	Yield,%⁴	Weight, g	Percent, %⁴
1	−	0	2,249^b	74.60	795^b	26.38	224	7.43	265	8.79	281^b	9.33	36	1.21
2	+	0	2,259^b	74.23	784^b	25.75	229	7.51	270	8.89	287^b	9.42	39	1.27
3	−	4,500	2,269^b	74.78	805^b	26.41	228	7.53	269	8.88	285^b	9.40	35	1.17
4	+	4,500	2,376^a	74.84	838^a	26.38	239	7.54	282	8.90	305^a	9.62	38	1.21
	SEM⁵		19	0.28	9	0.20	2	0.04	3	0.05	4	0.09	1	0.04
Main effect of nutrient density
	−		2,259	74.69	800	26.39	226	7.48	227	8.84	283	9.36	36	1.19
	+		2,317	74.54	811	26.07	234	7.52	276	8.89	296	9.52	39	1.24
	SEM⁵		14	0.24	6	0.14	1	0.03	2	0.04	4	0.07	1	0.03
Main effect of phytase
		0	2,254	74.42	790	26.06	226	7.47	267	8.84	284	9.38	37	1.24
		4,500	2,322	74.81	821	26.40	234	7.53	276	8.89	295	9.51	37	1.19
		SEM⁵	13	0.24	6	0.14	1	0.03	2	0.04	4	0.07	1	0.03
Source of variation							Probabilities
Source of variation							Probabilities
Nutrient density × phytase			0.005	0.237	0.009	0.117	0.091	0.271	0.094	0.404	0.018	0.362	0.718	0.713
Treatment 1 vs. 3			0.427	0.474	0.471	0.895	0.066	0.057	0.165	0.175	0.375	0.523	0.544	0.382
Treatment 2 vs. 4			< 0.001	0.012	< 0.001	0.014	< 0.001	0.653	< 0.001	0.808	< 0.001	0.041	0.901	0.135
Treatment 3 vs. 4			< 0.001	0.822	0.006	0.916	< 0.001	0.931	< 0.001	0.788	< 0.001	0.028	0.029	0.320
Main effect of nutrient density			< 0.001	0.385	0.206	0.085	< 0.001	0.220	< 0.001	0.225	< 0.001	0.028	0.006	0.076
Main effect of phytase			< 0.001	0.026	< 0.001	0.078	< 0.001	0.088	< 0.001	0.245	< 0.001	0.064	0.596	0.098

^a-b

Means not sharing a common superscript within column differ (P < 0.05).

Values are least-square means of 8 replicate pens with 14 birds selected from each pen for processing.

− = without increased nutrient density, + = with increased nutrient density; diets with increased nutrient density were formulated to contain 0.007, 0.015, 0.013, 0.021, 0.024%, and 61 kcal/kg higher digestible SAA, Lys, Thr, Val, Ile concentrations, and AME_n (obtained from Experiment 1), respectively, compared with the control diet.

One unit of phytase activity (FTU) is the quantity of enzyme to liberate 1 µmol of inorganic phosphate per minute from 0.0051 mol/L sodium phytate at pH 5.5 and 37°C.

⁴

Percent yield was calculated based on weight proportion to bird live weight at 40 d of age.

⁵

Pooled standard error of the mean.