Supplementation of guanidinoacetic acid and betaine improve growth performance and meat quality of ducks by accelerating energy metabolism

Figures & data

Table 1. Composition and nutrient contents of basal diets, % on dry matter or as fed basis.

Items	Starter phase (1–14 d)	Grower phase (15–35 d)
Ingredients
Corn	51.82	58.80
Soybean meal	28.09	17.78
Soybean oil	3.66	3.40
Defatted rice bran	4.00	5.00
Cottonseed meal	3.00	4.00
Rapeseed meal	3.00	4.00
Corn distillers dried grains with soluble	2.00	3.00
Limestone	1.34	1.44
Calcium hydrophosphate	1.66	1.16
NaCl	0.30	0.30
Methionine	0.13	0.12
Vitamin premix^A	0.03	0.03
Trace mineral premix^B	0.10	0.10
Zeolite powder	0.87	0.87
Total	100.00	100.00
Nutrient level
Digestible energy, MJ/kg	12.13	12.34
Crude protein	20.00	17.18
Calcium	1.00	0.90
Total phosphorus	0.72	0.64
Available phosphorus	0.50	0.42
Lysine	0.95	0.74
Methionine	0.45	0.40
Methionine + cystine	0.80	0.71

^AVitamin premix provided per kg of diet as follows: 15,000 IU of vitamin A, 3900 IU of vitamin D₃, 30 IU of vitamin E, 3 mg of vitamin K₃, 12.4 mg Vitamin C, 29 mg of vitamin C, 4.5 mg of C₆, 0.021 mg of C₁₂, 30 mg of pantothenic acid, 45 mg of nicotinamide, 1.2 mg of folic acid and 0.18 mg of biotin.

^BTrace minerals premix provided per kg of diet as follows: 8 mg of cuprum, 100 mg of manganese, 40 mg of zinc, 80 mg of ferric, 0.35 mg of iodine and 0.15 mg of selenium. NaCl = sodium chloride

Table 2. Effects of GAA and betaine supplementation on the growth performance of ducks.

Items	Control	GAA	Betaine	GAA + betaine	SEM	p-value
Initial BW, g	55.580	56.210	55.480	55.700	0.409	.929
D 1-14
ADFI, g	59.210	57.590	57.810	57.230	0.708	.816
ADG, g	44.460	45.510	46.890	46.470	0.532	.412
F/G	1.330^a	1.270^b	1.230^b	1.230^b	0.013	.013
D 14
BW, g	622.430	637.130	656.500	650.580	7.450	.412
D 15-35
ADFI, g	182.140	177.320	175.360	174.880	1.373	.263
ADG, g	83.680	85.590	86.690	85.430	0.708	.551
F/G	2.170	2.070	2.030	2.050	0.021	.094
D 35
BW, kg	2.340^a	2.440^b	2.480^b	2.430^b	0.018	.041
D 1-35
ADFI, g	132.970	129.430	128.340	127.820	0.933	.237
ADG, g	66.370	67.960	69.190	68.250	0.479	.231
F/G	1.990^a	1.910^b	1.860^b	1.870^b	0.018	.018

Data are the means of 6 replicates per treatment with 16 ducks per pen.

BW: body weight; ADFI : average daily feed intake; ADG : average daily gain; F/G : feed/gain; GAA: guanidinoacetic acid; SEM: standard error of the mean.

^a–bMeans within a row with different superscripts differ significantly at p < .05.

Table 3. Effects of GAA and betaine supplementation on the carcase traits and meat quality of ducks at 35 d of age.

Items	Control	GAA	Betaine	GAA + betaine	SEM	p-value
Carcase traits, %
Dressing percentage	81.440	81.600	80.960	82.050	0.516	.917
Semi-eviscerated percentage	76.160	76.420	75.870	76.500	0.498	.974
Eviscerated percentage	70.310	70.880	70.140	70.330	0.465	.956
breast muscle percentage	6.790^a	8.610^b	7.640^ab	7.930^b	0.213	.013
Thigh muscle percentage	12.000	12.710	12.880	12.440	0.167	.278
Abdominal fat percentage	2.370^a	1.700^b	1.770^b	1.650^b	0.091	.019
Meat quality
L*	50.240	50.280	49.610	49.180	0.867	.970
a*	13.820	14.810	13.240	13.540	0.512	.752
b*	10.130	11.010	10.560	10.010	0.455	.890
pH	5.690	5.720	5.840	5.810	0.034	.535
Drip loss, %	5.850^a	3.270^b	3.840^b	4.380^b	0.326	.009
Cooking loss, %	36.590	30.900	29.540	30.980	1.087	.091
Shear force value, N	33.390^a	25.930^b	25.040^b	27.210^b	1.192	.044

Data are the means of 6 replicates per treatment with 16 ducks per pen.

GAA: guanidinoacetic acid; SEM: standard error of the mean.

L*= lightness; a*=redness; b*= yellowness.

^a–bMeans within a row with different superscripts differ significantly at p < .05.

Table 4. Effects of GAA and betaine supplementation on the free amino acids in breast muscle of ducks at 35 d of age, ug/g.

Items	Control	GAA	Betaine	GAA + betaine	SEM	p-value
Serine	192.570^a	126.360^b	132.720^b	143.340^b	8.808	.030
Glycine	373.420	250.230	369.020	337.880	29.875	.493
Histidine	49.990	34.600	38.810	35.480	3.244	.364
Threonine	109.970	85.320	88.700	90.420	6.319	.574
Glutamic acid	109.660	77.160	86.060	92.620	5.268	.198
Glutamine	363.440	235.200	287.150	298.610	16.808	.068
Aspartic acid	26.510	23.980	38.070	24.600	2.481	.123
Asparagine	41.250	28.800	35.720	39.530	2.591	.388
Alanine	321.670	234.360	262.810	260.580	11.903	.074
Arginine	189.590	114.700	131.230	149.090	10.509	.078
Proline	79.980	62.050	69.460	62.390	3.044	.142
Cysteine	13.530	9.520	8.990	9.200	0.868	.230
Lysine	164.760	91.660	152.640	138.950	10.717	.092
Methionine	39.860^a	30.370^b	34.850^ab	29.400^b	1.496	.046
Valine	78.510	66.190	74.880	66.350	2.958	.384
Tyrosine	86.170	61.970	78.350	68.340	3.931	.154
Isoleucine	53.610	39.450	44.620	40.200	2.991	.365
Leucine	91.200	64.610	83.320	71.940	5.060	.294
Phenylalanine	78.070	51.440	67.550	58.670	3.862	.093
Tryptophan	24.490^a	15.910^b	19.230^b	17.680^b	1.107	.037
Total	2488.260^a	1743.910^b	2137.510^ab	2034.280^b	92.647	.042

Data are the means of 6 replicates per treatment with 16 ducks per pen.

GAA: guanidinoacetic acid; SEM: standard error of the mean.

^a–bMeans within a row with different superscripts differ significantly at p < .05.

Table 5. Effects of GAA and betaine supplementation on free amino acid contents in plasma of ducks at 35 d of age, ug/mL.

Items	Control	GAA	Betaine	GAA + betaine	SEM	p-value
Serine	56.840^a	65.770^ab	70.410^b	77.850^b	2.737	.037
Glycine	72.790	67.280	62.950	67.650	3.179	.793
Histidine	11.400	13.980	14.120	12.800	0.442	.084
Threonine	34.330	35.080	35.760	38.700	1.910	.878
Glutamic acid	28.520	28.520	30.630	29.300	1.123	.912
Glutamine	59.000	72.730	67.060	64.350	4.119	.722
Aspartic acid	9.130	9.520	9.690	9.640	0.347	.949
Asparagine	3.540^a	3.100^ab	2.990^ab	4.810^b	0.233	.019
Alanine	77.260	68.420	76.310	84.860	2.579	.163
Arginine	82.220	93.780	85.620	82.160	3.482	.634
Proline	29.690	29.880	35.690	36.750	1.755	.349
Cysteine	20.700	21.640	19.450	19.430	0.722	.674
Lysine	70.580	85.180	104.720	72.240	5.914	.142
Methionine	12.130	13.840	14.760	17.300	0.817	.152
Valine	33.620	35.110	34.890	39.190	1.119	.338
Tyrosine	36.000	35.480	36.720	32.370	1.191	.614
Isoleucine	15.820	16.790	17.120	16.610	0.603	.903
Leucine	23.330	23.280	24.970	24.900	0.854	.843
Phenylalanine	23.590^a	23.020^a	26.760^a	32.430^b	1.143	.005
Tryptophan	7.880^a	8.090^a	8.640^a	16.070^b	0.901	.001
Total	684.470	750.530	784.490	769.270	20.716	.480

Data are the means of 6 replicates per treatment with 16 ducks per pen.

GAA: guanidinoacetic acid; SEM: standard error of the mean.

^a–bMeans within a row with different superscripts differ significantly at p < .05.

Table 6. Effects of GAA and betaine supplementation on the biochemical indices in plasma of ducks at 35 d of age.

Items	Control	GAA	Betaine	GAA + betaine	SEM	p-value
GLU, mmol/L	7.550^a	5.000^b	5.090^b	6.230^b	0.362	.031
TP, g/L	29.280	32.770	29.800	32.230	0.601	.095
ALB, g/L	9.600	10.580	10.150	10.350	0.148	.100
HDL-C, mmol/L	2.590	3.100	3.140	2.940	0.095	.152
LDL-C, mmol/L	2.230	1.970	1.920	1.970	0.085	.615
TC, mmol/L	6.120	5.600	5.610	5.660	0.133	.475
TG, mmol/L	1.640^a	1.430^b	1.210^b	1.370^b	0.049	.008
NEFA, μmol/L	650.670^a	626.880^ab	594.890^b	512.100^c	18.263	.028
LA, mmol/L	12.220^a	9.460^b	9.950^b	7.900^c	0.571	.049
UA, μmol/L	258.500^a	227.830^b	224.000^b	196.000^c	6.815	.006
Urea, mmol/L	1.890	1.500	1.510	1.440	0.195	.437

Data are the means of 6 replicates per treatment with 16 ducks per pen.

GAA: guanidinoacetic acid; SEM: standard error of the mean; GLU: glucose; TP: total protein; ALB: albumin; HDL-C: high-density lipoprotein cholesterol; LDL-C: low-density lipoprotein cholesterol; TC: total cholesterol; TG: triglyceride; NEFA: Non-esterified fatty acid; LA: lactic acid; UA: uric acid.

^a–cMeans within a row with different superscripts differ significantly at p < .05.

Table 7. Effects of GAA and betaine supplementation on the activities of key enzymes in plasma of ducks, U/L at 35 d of age.

Items	Control	GAA	Betaine	GAA + betaine	SEM	p-value
CK	5141.230^c	5577.750^a	5246.980^bc	5447.130^ab	58.591	.025
LDH	846.500^a	676.480^bc	731.220^b	552.980^c	30.451	.002
AGAT	35.490^a	25.600^b	28.570^b	28.280^b	1.027	.001

Data are the means of 6 replicates per treatment with 16 ducks per pen.

GAA: guanidinoacetic acid; SEM: standard error of the mean; CK: creatine kinase; LDH: lactate dehydrogenase; AGAT: L-arginine: glycine amidino transferase.

^a–cMeans within a row with different superscripts differ significantly at p < .05.

Table 8. Effects of GAA and betaine supplementation on the creatine and adenylate in breast muscle of ducks at 35 d of age.

Items	Control	GAA	Betaine	GAA + betaine	SEM	p-value
ATP, umol/g	76.650^b	92.870^a	78.980^ab	86.800^a	2.392	.049
ADP, ug/g	0.650	1.050	0.800	1.410	0.175	.470
AMP, ug/g	0.040	0.010	0.010	0.010	0.046	.073
Cr, ug/mg	3.950^b	4.680^a	4.460^ab	4.930^a	0.133	.046

Data are the means of 6 replicates per treatment with 16 ducks per pen.

GAA: guanidinoacetic acid; SEM: standard error of the mean; ATP: Adenosine triphosphate; ADP: Adenosine diphosphate; AMP: Adenosine monophosphate adenylic acid; Cr: Creatine.

^a–bMeans within a row with different superscripts differ significantly at p < .05.