In Vitro Crude Protein Digestibility of Tenebrio Molitor and Hermetia Illucens Insect Meals and its Correlation with Chemical Composition Traits

Figures & data

Table 1. Chemical characteristics and in vitro crude protein digestibility of the 12 insect meal samples.

	DM	Ash	CP	EE	NDF	ADF	ADIP	Chitin	CPd
%
TM1	96.0	3.60	52.2	28.4	11.7	7.95	2.80	5.15	66.3
TM2	95.8	3.67	51.8	29.8	11.6	7.52	2.72	4.80	66.7
TM3	99.0	6.36	59.0	16.6	48.7	10.9	4.19	6.73	65.5
TM4	99.2	6.49	58.8	17.1	52.5	11.4	5.10	6.34	66.2
TM5	98.2	3.51	57.6	28.9	18.9	10.3	3.96	6.37	65.8
TM6	99.0	3.74	57.4	28.9	19.4	10.5	3.30	5.15	66.2
HI1	95.1	9.88	52.0	11.3	25.8	8.41	3.06	4.75	67.1
HI2	94.8	9.96	51.8	11.3	34.4	8.80	3.65	4.50	67.3
HI3	98.8	6.43	58.8	12.9	5.99	4.89	1.96	2.93	67.6
HI4	98.9	6.52	58.4	11.6	6.03	4.69	1.83	2.86	68.7
HI5	95.9	4.72	49.9	29.0	18.3	8.30	3.32	4.98	66.8
HI6	95.9	4.64	50.5	28.4	19.2	8.53	3.03	5.50	66.0
TM	97.9	4.56^Footnoteb	56.1	24.9	27.1	9.77^Footnotea	3.68^Footnotea	5.75^Footnotea	66.1^Footnoteb
HI	96.6	7.02^Footnotea	53.6	17.4	18.3	7.27^Footnoteb	2.98^Footnoteb	4.25^Footnoteb	67.3^Footnotea
P value	0.106	0.028	0.254	0.119	0.339	0.035	0.036	0.012	0.022

TM 1-6: Tenebrio molitor samples from 1 to 6; HI 1-6: Hermetia illucens samples from 1 to 6; DM, dry matter; CP, crude protein; EE, ether extract; NDF, neutral detergent fibre; ADF, acid detergent fibre; ADIP, protein linked to ADF; CPd, crude protein digestibility.

^a,bP<0.05.

Table 2. Correlation coefficients between crude protein digestibility and the different traits of chemical composition of Tenebrio molitor larvae meal samples.

CPd	-	-0.429	0.190	-0.459	-0.137	0.017	-0.747	0.036	-0.891
	(0.396)	(0.719)	(0.360)	(0.796)	(0.975)	(0.035)	(0.951)	(0.017)
DM	-	-	0.617	0.582	-0.622	0.544	0.586	0.684	0.657
		(0.192)	(0.195)	(0.187)	(0.090)	(0.103)	(0.137)	(0.157)
Ash	-	-	-	0.649	-0.993	0.981	0.687	0.599	-0.009
		(0.162)	(<0.001)	(0.005)	(0.137)	(0.214)	(0.099)
CP	-	-	-	-	-0.667	0.777	0.989	0.859	0.633
			(0.148)	(0.069)	(<0.001)	(0.028)	(0.178)
EE	-	-	-	-	-	-0.979	-0.687	-0.902	0.004
			(0.001)	(0.132)	(0.014)	(0.999)
NDF	-	-	-	-	-	-	0.705	0.935	0.174
				(0.053)	(0.006)	(0.741)
ADF	-	-	-	-	-	-	-	0.853	0.841
				(0.031)	(0.033)
ADIP	-	-	-	-	-	-	-	-	-0.442
					(0.381)

DM, dry matter; CP, crude protein; EE, ether extract; NDF, neutral detergent fibre; ADF, acid detergent fibre; ADIP, protein linked to ADF; CPd, crude protein digestibility. P values are indicated in brackets.

Table 3. Correlation coefficients between crude protein digestibility and the different traits of chemical composition of Hermetia illucens larvae meal samples.

CPd	-	0.799	0.157	0.941	-0.699	-0.625	0.901	-0.791	-0.992
	(0.057)	(0.766)	(0.005)	(0.103)	(0.184)	(0.001)	(0.061)	(0.001)
DM	-	-	-0.418	0.602	-0.221	-0.752	-0.677	-0.661	0.657
		(0.410)	(0.114)	(0.674)	(0.093)	(0.121)	(0.138)	(0.131)
Ash	-	-	-	0.009	-0.793	0.604	0.220	0.280	-0.078
		(0.987)	(0.059)	(0.204)	(0.675)	(0.551)	(0.973)
CP	-	-	-	-	-0.614	-0.756	-0.966	-0.922	-0.973
			(0.195)	(0.082)	(0.002)	(0.009)	(0.001)
EE	-	-	-	-	-	-0.016	0.416	0.343	0.655
			(0.976)	(0.414)	(0.501)	(0.158)
NDF	-	-	-	-	-	-	0.888	0.923	0.688
				(0.018)	(0.009)	(0.131)
ADF	-	-	-	-	-	-	-	0.966	0.941
				(0.002)	(0.005)
ADIP	-	-	-	-	-	-	-	-	0.846
					(0.034)

DM, dry matter; C P, crude protein; EE, ether extract; NDF, neutral detergent fibre; ADF, acid detergent fibre; ADIP, protein linked to ADF; CPd, crude protein digestibility. P values are indicated in brackets.

Table 4. Regression of the crude protein digestibility on the variables of chemical characteristics variables of Tenebrio molitor larvae meal samples.

	Variables	R^2	RSD
Intercept	Chitin	ADIP
68.195	-0.3325	-	0.7945	12.06
(0.4903)	(0.0845)
72.425	-0.2672	0.0845	0.9213	6.29
(0.4959)	(0.0674)	(0.0385)

ADIP, protein linked to ADF; RSD, residual standard deviation. The standard error values of the regression coefficients are indicated in brackets.

Table 5. Regression of the crude protein digestibility on the variables of chemical characteristics variables of Hermetia illucens larvae meal samples.

	Variables	R^2	RSD
Intercept	Chitin	CP
71.57	-0.9705	-	0.9830	2.50
(0.2804)	(0.064)
80.09	-1.412	-0.1243	0.9940	1.17
(3.62)	(0.191)	(0.0529)

CP, crude protein; RSD, residual standard deviation. The standard error values of the regression coefficients are indicated in brackets.