Response of modern broiler chickens to dietary calcium and phosphorus levels below recommendations

Figures & data

Table 1. Ingredient and nutrient composition of experimental diets (% as fed).

	Starter		Grower				Finisher^a
	T 1	T 2–7	T 1	T 2,3	T 4,5	T 6,7	T 1	T 2	T 3,4,6	T 5,7
Ingredients	100% Ca&NPP^b	94% Ca&NPP	100% Ca&NPP	95% Ca&NPP	91% Ca&NPP	86% Ca&NPP	100% Ca&NPP	91% Ca&NPP	83% Ca&NPP	77% Ca&NPP
Corn	46.34	46.88	48.79	49.07	49.35	49.63	53.38	53.92	54.39	54.75
Wheat	5.00	5.00	6.00	6.00	6.00	6.00	7.00	7.00	7.00	7.00
Soybean meal	19.28	19.98	14.49	14.39	14.30	14.20	9.69	9.95	10.11	10.14
Sunflower meal	3.50	3.50	4.50	4.50	4.50	4.50	5.00	5.00	5.00	5.00
Full-fat soybean	15.89	14.87	15.22	15.28	15.34	15.39	12.40	11.95	11.64	11.53
Maize gluten meal	1.50	1.50	1.00	1.00	1.00	1.00	1.00	1.00	1.00	1.00
Poultry meal	3.00	3.00	4.00	4.00	4.00	4.00	5.00	5.00	5.00	5.00
Soybean oil	1.40	1.40	2.50	2.40	2.30	2.20	3.50	3.40	3.30	3.20
Dicalcium phosphate, 23% Ca, 18% P	1.04	0.87	0.95	0.84	0.72	0.61	0.72	0.53	0.47	0.33
Monocalcium phosphate, 20% Ca, 21% P	0.70	0.70	0.50	0.50	0.50	0.50	0.40	0.40	0.30	0.30
Limestone	0.79	0.74	0.67	0.64	0.61	0.57	0.58	0.53	0.46	0.42
Sodium bicarbonate	0.18	0.18	0.15	0.15	0.15	0.15	0.14	0.14	0.14	0.14
Salt	0.23	0.23	0.22	0.22	0.22	0.22	0.20	0.20	0.20	0.20
DL-Met, 99%	0.16	0.16	0.00	0.00	0.00	0.00	0.14	0.14	0.14	0.14
Methionine hydroxy analogue, 88%	0.20	0.20	0.15	0.15	0.15	0.15	0.10	0.10	0.10	0.10
L-Lys, 99%	0.39	0.39	0.15	0.15	0.15	0.15	0.36	0.36	0.36	0.36
Vitamin premix^c	0.10	0.10	0.34	0.34	0.34	0.34	0.10	0.10	0.10	0.10
Mineral premix^d	0.20	0.20	0.10	0.10	0.10	0.10	0.20	0.20	0.20	0.20
Choline chloride, 75%	0.05	0.05	0.20	0.20	0.20	0.20	0.04	0.04	0.04	0.04
Salinomisin	0.05	0.05	0.05	0.05	0.05	0.05	0.05	0.05	0.05	0.05
Nutrient level^e
ME^f, kcal/kg	3000.00	3000.00	3100.00	3100.00	3100.00	3100.00	3200.00	3200.00	3200.00	3200.00
Crude protein	23.00 (22.89)	23.00 (22.95)	21.50 (21.41)	21.50 (21.41)	21.50 (21.55)	21.50 (21.21)	19.50 (19.22)	19.50 (19.40)	19.50 (19.39)	19.50 (19.33)
Crude ash	6.53 (6.58)	6.32 (6.39)	6.00 (5.90)	5.86 (5.81)	5.72 (5.70)	5.58 (5.55)	5.38 (5.45)	5.14 (5.20)	4.92 (4.87)	4.74 (4.75)
Ca	0.96 (0.98)	0.90 (0.92)	0.87 (0.85)	0.83 (0.83)	0.79 (0.78)	0.75 (0.75)	0.78 (0.77)	0.71 (0.71)	0.65 (0.63)	0.60 (0.59)
Total P	0.75 (0.77)	0.73 (0.74)	0.70 (0.72)	0.68 (0.69)	0.66 (0.68)	0.64 (0.65)	0.63 (0.62)	0.60 (0.59)	0.57 (0.58)	0.55 (0.53)
NPP^g	0.48	0.45	0.44	0.42	0.40	0.38	0.39	0.39	0.33	0.30
Lys	1.44	1.44	1.29	1.29	1.29	1.29	1.15	1.15	1.15	1.15
Met + Cys	1.08	1.08	0.99	0.99	0.99	0.99	0.90	0.90	0.90	0.90

^aFinisher diets was used up to end of 37 days of age, then same diets only without anticoccidial introduced through 3 days.

^bDietary calcium and non-phytate phosphorus as percentage of recommended levels for treatment groups.

^cSupplied per kg diet: 10,000 U vitamin A, 4500 U vitamin D3, 65 mg vitamin E, 2.8 mg vitamin B1, 6.5 mg vitamin B2, 3.2 mg vitamin B6, 0.017 mg vitamin B12, 3.5 mg vitamin K3, 18 mg pantothenic acid, 55 mg niacin, 0.18 mg biotin,1.9 mg folic acid.

^dSupplied per kg diet: 20 mg Fe, 16 mg Cu, 110 mg Zn, 120 mg Mn, 1.25 mg I, 0.9 mg Co, 0.3 mg Se.

^eValues in parenthesis represent analysed contents of nutrients.

^fME: metabolisable energy.

^gNPP: non-phytate-phosphorus.

Figure 1. Relationship between the Ca intake and the body weight gain (BWG) and feed conversion ratio (FCR) of broilers.

Table 2. Effects of different dietary Ca and non-phytate P levels on feed intake (FI), body weight gain (BWG), feed conversion ratio (FCR), mortality (%) and European Production Efficiency Factor (EPEF) and Ca and non-phytate P intake (% of BWG) in broiler chickens.

	T1 (Control)	T2	T3	T4	T5	T6	T7
Items	100/100/100^1	94/95/91	94/95/83	94/91/83	94/91/77	94/86/83	94/86/77	p^2 Value
0–10 days
FI, g	301.09 ± 3.65	305.15 ± 1.42						.258
BWG, g	249.46 ± 3.48	252.64 ± 1.03						.276
FCR	1.21 ± 0.02	1.21 ± 0.01						.922
Mortality	0.88 ± 0.16	0.71 ± 0.09						.319
11–41 days								Linear	Quadratic
FI, g	3897.89 ± 15.92^a^b	3902.15 ± 16..33^a	3891.75 ± 14.33^a^b	3873.04 ± 11.01^a^b	3869.30 ± 17.91^a^b	3859.20 ± 11.39^b	3870.90 ± 16.73^a^b	.017	.611
BWG, g	2253.72 ± 19.13^c	2315.20 ± 13.47^a^b	2320.35 ± 9.63^a^b	2316.47 ± 10.93^a	2294.48 ± 19.20^a^b	2300.84 ± 10.66^a^b	2284.53 ± 14.34^b^c	.648	.003
FCR	1.73 ± 0.01^a	1.69 ± 0.01^b^c	1.68 ± 0.01^b^c	1.67 ± 0.01^c	1.69 ± 0.01^b^c	1.68 ± 0.01^b^c	1.70 ± 0.01^b	.059	<.001
Mortality	1.38 ± 0.266^a^b	1.56 ± 0.33^a	1.50 ± 0.32^a^b	0.94 ± 0.175^a^b	1.38 ± 0.360^a^b	0.88 ± 0.226^a^b	0.82 ± 0.132^b	.028	.569
0–41 days
FI, g	4197.75 ± 17.74^a^b	4209.31 ± 20.61^a	4196.42 ± 15.04^a^b	4178.58 ± 12.50^a^b	4176.74 ± 20.13^a^b	4164.03 ± 13.69^b	4174.39 ± 16.22^a^b	.040	.859
BWG, g	2503.18 ± 18.08^b	2566.03 ± 14.20^a	2570.84 ± 11.64^a	2568.79 ± 11.49^a	2545.86 ± 18.89^a	2554.06 ± 9.98^a	2541.96 ± 13.67^a	.419	.004
FCR	1.68 ± 0.01^a	1.64 ± 0.01^b	1.63 ± 0.01^b	1.63 ± 0.01^b	1.64 ± 0.01^b	1.63 ± 0.01^b	1.64 ± 0.01^b	.030	.002
Mortality	2.26 ± 0.270	2.07 ± 0.39	2.37 ± 0.45	1.51 ± 0.163	2.32 ± 0.468	1.38 ± 0.362	1.69 ± 0.299	.104	.919
EPEF^3	362.13 ± 4.08^c	380.00 ± 2.79^a^b	381.40 ± 2.74^a^b	386.00 ± 4.50^a	376.18 ± 5.13^a^b	383.40 ± 3.84^a^b	377.74 ± 4.59^b	.046	.003
Ca intake	1.38 ± 0.01^a	1.25 ± 0.01^b	1.18 ± 0.01^c	1.16 ± 0.01^d	1.11 ± 0.01^f	1.14 ± 0.01^e	1.10 ± 0.01^gf	<.001	.<001
NPP intake	0.69 ± 0.01^a	0.62 ± 0.01^b	0.59 ± 0.01^c	0.58 ± 0.01^d	0.56 ± 0.01^f	0.57 ± 0.01^e	0.55 ± 0.01^gf	<.001	.<001

¹Calcium and available phosphorus as percentage of recommended levels for starter/grower/finisher.

²T test was applied during 0–10 days because of all treatment groups were received same Ca and P level (94%) compared to control one (100%).

³EPEF: [viability 0–41 days (%) * BW 41 days (kg) * 100]/[age (d) * FCR 0–41 days].

^acValues within a row not sharing the same superscript are significantly different (p < .05).

Table 3. Effects of different dietary Ca and non-phytate P levels on relative weights (weight/BW, %) of carcase and cuts up, and tibia weight (weight/BW, %), tibia ash (% of tibia dry matter weight) and tibia phosphorus (% of tibia ash weight).

	T1 (Control)	T2	T3	T4	T5	T6	T7	p Value
Items	100/100/100^a	94/95/91	94/95/83	94/91/83	94/91/77	94/86/83	94/86/77	Linear	Quadratic
Carcase yield	70.01 ± 0.49	70.30 ± 0.54	69.75 ± 0.48	69.40 ± 0.38	69.71 ± 0.54	70.07 ± 0.43	70.03 ± 0.44	.711	.754
Breast	29.71 ± 0.29	30.02 ± 0.38	30.18 ± 0.33	30.45 ± 0.47	29.28 ± 0.46	30.03 ± 0.34	29.72 ± 0.37	.705	.820
Drumsticks	19.61 ± 0.34	19.82 ± 0.29	19.60 ± 0.24	20.00 ± 0.20	19.87 ± 0.19	19.56 ± 0.28	20.14 ± 0.17	.953	.844
Tibia weight	0.43 ± 0.01	0.44 ± 0.01	0.43 ± 0.01	0.42 ± 0.01	0.42 ± 0.01	0.43 ± 0.01	0.44 ± 0.01	.441	.125
Tibia ash	36.59 ± 0.48	36.13 ± 0.43	36.15 ± 0.52	36.25 ± 0.48	36.04 ± 0.46	35.07 ± 0.58	35.74 ± 0.54	.102	.084
Tibia phosphorus	17.36 ± 0.07	17.44 ± 0.07	17.45 ± 0.08	17.25 ± 0.06	17.03 ± 0.06	16.93 ± 0.16	17.01 ± 0.07	.211	.105

^aCalcium and non-phytate phosphorus as percentage of recommended levels for starter/grower/finisher.