Nutritional Value of Acacia Amentacea and Parkinsonia Texana Grown in Semiarid Conditions

Figures & data

Figure 1. Air temperature mean and monthly rainfall recorded during the course of the study. The arrows indicate the drought (D) and rainfall (R) periods at the study sites.

Table 1. Pearson correlation coefficients among chemical composition, in vitro fermentation parameters, digestibility and gross energy losses of leaves of two native shrub species in Northeastern Nuevo Leon, Mexico.

	OM	NDF	CT	CP	NSC	ME	IVTOMD	GEL	A	c	L	P	PF
DM	-0.147^*	0.105	-0.132	-0.294^**	0.213^**	0.141^*	0.197^**	-0.217^**	0.173^*	0.189^**	0.099	0.055	-0.116
OM		0.073	0.022	0.006	-0.098	-0.210^**	-0.089	0.053	-0.103	-0.096	-0.001	-0.131	0.075
NDF			0.139^*	-0.606^**	0.016	0.093	-0.088	0.040	-0.062	0.002	0.084	-0.104	-0.145^*
CT				-0.092	-0.342^**	-0.359^**	-0.702^**	0.707^**	-0.731^**	-0.630^**	-0.308^**	0.151^*	0.065
CP					-0.224^**	0.055	0.025	0.004	-0.017	-0.046	0.045	-0.013	0.078
NSC						0.199^**	0.478^**	-0.477^**	0.443^**	0.347^**	-0.022	-0.050	-0.056
ME							0.575^**	-0.540^**	0.361^**	0.328^**	0.366^**	0.226^**	-0.336^**
IVTOMD								-0.923^**	0.818^**	0.626^**	0.246^**	-0.054	-0.217^**
GEL									-0.868^**	-0.684^**	-0.261^**	0.068	0.246^**
A										0.751^**	0.235^**	-0.135^*	-0.194^**
c											0.420^**	-0.140^*	-0.137^*
L												0.091	-0.028
P													-0.233^**
PF													1

OM, organic matter (% DM); NDF, neutral detergent fibre (% DM); CT, condensed tannins (% DM); CP, crude protein (% DM); NSC, non-structural carbohydrates (% DM); ME, metabolisable energy (Mcal ME/kg DM); IVTOMD, in vitro true organic matter digestibility (%); GEL, gross energy losses (%, as methane production); A, total gas production (mL/g DM); c, the rate of gas production (/h); L, the initial delay before gas production begins (h); P, purines (μmol); PF, partitioning factor; DM, dry matter (%).

*P<0.05

**P<0.01.

Table 2. Effect of seasons and plant species on chemical composition, in vitro true organic matter digestibility and gross energy losses of leaves of two native shrub species in Northeastern Nuevo Leon, Mexico.

	DM, %	OM, % DM	NDF, % DM	CT, % DM	CP, % DM	EE, % DM	IVTOMD, %	GEL, % (as methane production)
A. amentacea
Spring	95.9	85.9	52.8	18.5	15.0	0.6	42.6	7.1
Summer	96.9	80.1	45.4	20.3	13.6	1.0	46.8	6.9
Autumn	95.2	80.7	49.6	18.4	15.4	0.8	53.2	6.5
Winter	92.9	81.6	48.0	18.8	15.2	1.6	58.7	6.2
Mean	95.2	82.1	49.0	19.0	14.8	1.0	50.3	6.7
P. texana
Spring	94.7	84.2	36.8	12.4	19.2	1.7	76.7	4.1
Summer	96.1	80.4	28.8	12.3	20.1	1.5	84.2	2.3
Autumn	93.6	81.9	32.8	6.6	22.2	1.5	84.2	2.3
Winter	91.6	84.2	32.6	7.4	21.6	1.6	82.5	2.7
Mean	94.0	82.7	32.8	9.7	20.8	1.6	81.9	2.9
Probability
A	^***	ns	^***	^***	^***	^***	^***	^***
B	^***	^***	^***	^***	^***	^***	^***	^***
A*B	^***	ns	ns	^***	^***	^***	^***	^***
SEM
A	0.14	0.90	0.16	0.19	0.19	0.03	0.21	0.06
B	0.27	1.13	0.80	0.41	0.25	0.06	0.14	0.18
A*B	0.32	1.39	0.61	0.50	0.39	0.06	1.14	0.16

DM, dry matter; OM, organic matter; NDF, neutral detergent fibre; CT, condensed tannins; CP, crude protein; EE, ether extract; IVTOMD, in vitro true organic matter digestibility; GEL, gross energy losses; A, species; B, season.

***P<0.001; ns, not significant.

Table 3. Effect of polyethylene glycol on fermentation characteristics, purines, partitioning factor and metabolisable energy of leaves of two native shrub species in northeastern Nuevo Leon, Mexico.

	PEG	A, mL/g DM	c, /h	L, h	P, μmol	PF	ME, Mcal kg DM
A. amentacea
Spring	-	109	0.04	0.42	6.1	4.9	1.2
+	164	0.06	0.14	6.9	2.8	1.6
Summer	-	97	0.02	0.40	7.1	5.9	1.9
+	163	0.06	0.59	5.5	3.0	2.0
Autumn	-	89	0.04	1.03	15.2	7.2	2.2
+	157	0.06	0.93	13.2	3.7	2.1
Winter	-	105	0.04	0.66	7.0	6.5	1.5
+	147	0.06	0.36	6.9	4.3	1.8
Mean		129	0.05	0.56	8.5	4.8	1.8
P. texana
Spring	-	171	0.07	0.52	5.7	4.8	1.7
+	193	0.08	1.13	4.2	4.1	1.9
Summer	-	186	0.06	0.49	7.3	4.8	2.2
+	208	0.08	1.28	6.4	4.1	2.2
Autumn	-	188	0.07	1.45	9.6	4.7	2.4
+	202	0.08	1.88	11.5	4.3	2.4
Winter	-	187	0.08	1.01	4.9	4.7	2.0
+	195	0.09	1.03	5.3	4.4	2.2
Mean		190	0.08	1.10	6.9	4.5	2.1
Probability
A		^***	^***	^***	^***	^***	^***
PEG		^***	^***	^***	ns	^***	^***
A*PEG		^***	ns	^***	ns	^***	^***
B		ns	^***	^***	^***	^***	^***
A*B		^***	^***	ns	^***	^***	^***
B*PEG		^***	ns	^***	ns	^***	^***
A*PEG*B		ns	ns	ns	^***	^***	^***
SEM
A		1.08	0.0008	0.042	0.218	0.048	0.011
PEG		1.08	0.0008	0.042	0.218	0.048	0.011
A*PEG		1.53	0.0011	0.060	0.308	0.069	0.016
B		2.42	0.0018	0.063	0.780	0.107	0.056
A*B		2.43	0.0018	0.073	0.384	0.128	0.022
B*PEG		2.43	0.0018	0.073	0.384	0.128	0.022
A*PEG*B		3.44	0.0025	0.104	0.544	0.182	0.032

PEG, polyethylene glycol; A, total gas production; c, the rate of gas production; L, the initial delay before gas production begins; P, purines; PF, partitioning factor; ME, metabolizable energy; A, species; B, season.

***P<0.001; ns, not significant.