Effect of different levels of lysine and threonine on carcass characteristics, intestinal microflora and growth performance of broiler chicks

Figures & data

Table 1. Ingredient composition of the experimental diets (% as-fed basis).

	Basal diets
	Starter	Grower
Ingredients, %
Maize	56.70	65.50
Soybean meal	30.05	21.35
Safflower meal	4.38	5.52
l-Lys HCl	0.02	0.18
l-Thr	0.02	0.08
dl-Met	0.17	0.17
DCP	2.90	2.60
Oyster shell	0.57	0.57
Salt	0.42	0.30
Soybean oil	3.19	1.94
Mineral premix	0.25	0.25
Vitamin premix	0.25	0.25
Sand	1.08	1.29
Calculated contents
ME, kcal/kg	3000	3000
CP, %	21.56	18.75
TSAA, %	0.84	0.68
Lys, %	1.03	0.94
Thr, %	0.75	0.69
Ca, %	0.94	0.84
Avail. P, %	0.42	0.33
Lys/Thr	1.37	1.36

Vitamin premix provided per kilogram of diet: vitamin A (source unspecified), 11,894 U; cholecalciferol (d-activatedanimal sterol), 2379 U; vitamin E (source unspecified), 7.9 U; niacin, 27.8 mg; pantothenic acid, 17.2mg; riboflavin, 6.6 mg; thiamine, 1.32 mg; pyridoxine, 1.32 mg; vitamin K, 0.72 mg; folic acid, 0.70 mg; biotin, 0.12mg; cobalamin, 0.01 mg; selenium, 0.12 mg.

Mineral premix provided per kilogram of diet: manganese, 146 mg; zinc, 120 mg; iron, 48 mg; copper, 4.8 mg; iodine, 2.9 mg; calcium, 278 mg.

Table 2. Effect of different levels of lysine and threonine on carcass characteristics at day 21.

Treatments	Live weight, g	Carcass weight, g	Breast, %	Thigh, %	Liver, %	Heart, %	Abdominal fat, %
Lys effect
100%	568.55^c	326.44^c	16.93^c	13.24^d	1.40^b	0.330	0.570^a
110%	575.89^b	327.11^c	17.46^b	13.67^c	1.55^a	0.340	0.570^a
120%	598.55^a	353.00^a	18.02^a	14.26^a	1.60^a	0.344	0.574^a
130%	598.44^a	341.33^b	17.44^b	13.94^b	1.44^b	0.319	0.537^b
Thr effect
100%	578.42^b	331.08^c	17.40^b	13.61^b	1.49	0.327	0.568^a
110%	590.00^a	337.33^b	17.35^b	13.79^a	1.50	0.339	0.572^a
120%	587.67^a	342.50^a	17.62^a	13.94^a	1.56	0.333	0.546^b
Lys and Thr interactions
100% Lys +100% Thr	574.33^e	324.33^e	17.35^cde	13.09^f	1.40^cde	0.330	0.562^cde
100% Lys +110% Thr	554.33^g	322.33^e	17.09^def	13.76^bcd	1.37^de	0.320	0.599^a
100% Lys +120% Thr	565.33^f	338.33^c	16.89^ef	13.80^bcd	1.36^e	0.340	0.548^ef
110% Lys +100% Thr	566.00^f	332.67^d	17.22^def	13.30^ef	1.56^abc	0.327	0.571^cd
110% Lys +110% Thr	584.67^d	338.67^c	17.58^bc	13.44^def	1.44^cde	0.350	0.581^abc
110% Lys +120% Thr	592.33^c	313.33^f	17.51^bcd	13.63^cde	1.39^cde	0.343	0.557^def
120% Lys +100% Thr	600.33^b	342.33^b	17.47^cd	13.85^bc	1.53^abcd	0.340	0.593^ab
120% Lys +110% Thr	610.00^a	353.00^b	17.96^b	14.08^b	1.66^a	0.350	0.572^bcd
120% Lys +120% Thr	608.33^a	367.33^a	18.62^a	15.15^a	1.67^a	0.343	0.556^def
130% Lys +100% Thr	592.33^c	339.67^b	17.63^bc	13.90^bc	1.52^abcd	0.313	0.548^ef
130% Lys +110% Thr	581.00^d	342.00^b	17.39^cd	13.98^bc	1.61^ab	0.337	0.538^fg
130% Lys +120% Thr	603.00^b	329.67^d	16.81^f	13.34^ef	1.48^bcde	0.307	0.525^g
SEM	1.604	1.388	0.147	0.120	0.051	0.014	0.007
p Value
Lys	.001	.001	.001	.001	.001	.146	.001
Thr	.001	.001	.039	.003	.012	.511	.001
Lys + Thr	.001	.001	.002	.001	.184	.692	.008

Means within a column with no common superscript differ significantly. SEM: standard error of means.

Table 3. Effect of different levels of lysine and threonine on carcass characteristics at day 42.

Treatments	Live weight, g	Carcass weight, g	Breast, %	Thigh, %	Liver, %	Heart, %	Abdominal fat, %
Lys effect
100%	1909.22^d	1164.44^d	24.88^d	21.14^d	2.25^c	0.443^c	1.39^a
110%	2068.67^c	1268.55^c	25.31^c	21.87^b	2.31^b	0.460^b	1.34^b
120%	2202.33^a	1399.33^a	26.32^a	23.73^a	2.34^a	0.477^a	1.33^b
130%	2190.55^b	1372.55^b	25.89^b	21.68^c	2.26^c	0.430^c	1.38^a
Thr effect
100%	2067.25^c	1273.33^c	25.42^c	22.10^b	2.27^b	0.451	1.35
110%	2078.67^b	1290.33^b	25.56^b	21.87^c	2.30^a	0.449	1.36
120%	2132.17^a	1340.00^a	25.82^a	22.33^a	2.30^a	0.453	1.37
Lys and Thr interactions
100% Lys +100% Thr	1901.67^k	1148.67^i	25.12^f	20.72^i	2.21^f	0.420^e	1.39^a
100% Lys +110% Thr	1889.67^l	1140.67^j	24.76^g	21.21^gh	2.25^ef	0.430^cde	1.38^ab
100% Lys +120% Thr	2053.33^h	1243.33^g	24.77^g	21.53^g	2.25^ef	0.440^bcde	1.40^a
110% Lys +100% Thr	1936.33^j	1298.00^e	25.30^ef	21.44^g	2.27^de	0.453^bcd	1.35^b
110% Lys +110% Thr	2043.33^i	1342.67^d	25.62^cd	21.06^h	2.27^de	0.450^bcde	1.33^b
110% Lys +120% Thr	2125.33^f	1264.33^f	25.73^cd	21.87^f	2.31^bcd	0.453^bcd	1.35^b
120% Lys +100% Thr	2204.00^c	1365.67^c	25.89^c	22.94^c	2.32^abc	0.460^bc	1.34^b
120% Lys +110% Thr	2210.67^b	1363.00^c	26.17^b	23.33^b	2.33^ab	0.460^bc	1.33^b
120% Lys +120% Thr	2290.67^a	1492.33^a	27.03^a	24.91^a	2.37^a	0.500^a	1.33^b
130% Lys +100% Thr	2192.33^d	1366.67^c	25.53^de	22.55^d	2.35^ab	0.470^b	1.34^b
130% Lys +110% Thr	2155.67^e	1385.33^b	26.22^b	22.21^e	2.33^ab	0.470^b	1.37^ab
130% Lys +120% Thr	2109.33^g	1204.00^h	25.11^f	21.48^g	2.24^ef	0.423^de	1.34^b
SEM	1.941	2.375	0.091	0.108	0.016	0.009	0.025
p Value
Lys	.001	.001	.001	.001	.001	.001	.063
Thr	.001	.001	.001	.001	.016	.099	.620
Lys + Thr	.001	.001	.001	.001	.001	.047	.339

Means within a column with no common superscript differ significantly. SEM: standard error of means.

Table 4. Effect of different levels of lysine and threonine on intestinal microflora.

	Total intestinal microflora
Treatments	Day 21, cfu	Day 42, cfu
Lys effect
100%	37.75 × 10^4b	32.74 × 10^5a
110%	38.24 × 10^4a	32.19 × 10^5b
120%	37.84 × 10^4b	32.04 × 10^5b
130%	37.30 × 10^4c	32.00 × 10^5b
Thr effect
100%	37.84 × 10^4a	32.29 × 10^5
110%	37.65 × 10^4b	32.32 × 10^5
120%	37.87 × 10^4a	32.12 × 10^5
Lys and Thr interactions
100% Lys +100% Thr	36.93 × 10^4g	32.97 × 10^5a
100% Lys +110% Thr	38.00 × 10^4c	33.03 × 10^5a
100% Lys +120% Thr	38.33 × 10^4b	32.23 × 10^5b
110% Lys +100% Thr	38.43 × 10^4ab	32.30 × 10^5b
110% Lys +110% Thr	37.80 × 10^4cd	32.10 × 10^5b
110% Lys +120% Thr	38.50 × 10^4ab	32.17 × 10^5b
120% Lys +100% Thr	38.70 × 10^4a	31.90 × 10^5b
120% Lys +110% Thr	37.73 × 10^4cd	32.07 × 10^5b
120% Lys +120% Thr	37.10 × 10^4fg	32.17 × 10^5b
130% Lys +100% Thr	37.30 × 10^4ef	32.00 × 10^5b
130% Lys +110% Thr	37.67 × 10^4fg	32.07 × 10^5b
130% Lys +120% Thr	37.53 × 10^4de	31.93 × 10^5b
SEM	1105.54	13088.02
p Value
Lys	.001	.001
Thr	.020	.100
Lys + Thr	.001	.010

Means within a column with no common superscript differ significantly.

SEM: standard Error of Means.

Table 5. Effect of different levels of lysine and threonine on growth performance at day 42.

Treatments	Feed intake, g day^−1	Body weight gain, g day^−1	FCR
Lys effect
100%	88.11	45.47^c	1.94^a
110%	88.67	48.80^b	1.82^b
120%	89.75	51.79^a	1.74^c
130%	88.35	49.17^b	1.81^b
Thr effect
100%	88.98	49.20	1.80
110%	89.45	49.47	1.80
120%	89.98	50.76	1.77
Lys and Thr interactions
100% Lys +100% Thr	88.55	45.20^c	1.95^a
100% Lys +110% Thr	88.80	44.99^c	1.97^a
100% Lys +120% Thr	89.05	48.88^b	1.83^a
110% Lys +100% Thr	88.84	46.10^c	1.92^a
110% Lys +110% Thr	89.06	48.60^b	1.84^a
110% Lys +120% Thr	89.33	50.55^ab	1.77^ab
120% Lys +100% Thr	89.40	52.47^a	1.71^b
120% Lys +110% Thr	89.60	52.61^a	1.70^b
120% Lys +120% Thr	89.92	54.52^a	1.67^b
130% Lys +100% Thr	88.72	52.19^a	1.71^b
130% Lys +110% Thr	88.90	51.30^ab	1.74^ab
130% Lys +120% Thr	89.20	50.21^ab	1.78^ab
SEM	0.56	2.375	0.091
p Value
Lys	.501	.001	.001
Thr	.061	.561	.165
Lys + Thr	.155	.001	.001

Means within a column with no common superscript differ significantly. SEM: standard error of means.