Table 3.

Least square means for growth performance and carcass characteristics of growing–finishing pigs fed increasing STTD P from 24 to 130 kg BW¹

	STTD P, % of NRC (2012) requirement2							P-value
Item	80	90	100	115	130	150	SEM	Linear	Quadratic
Grower period (day 0 to 56)
ADG, g	886	910	904	933	930	917	11.7	0.001	0.003
ADFI, g	1,874	1,922	1,919	1,984	1,983	1,930	35.5	0.017	0.004
G:F, g/kg	473	474	471	470	469	476	4.9	0.958	0.271
STTD P intake, g/d	4.3	5.0	5.5	6.6	7.4	8.3	0.12	<0.001	0.009
STTD P intake, g/kg gain	4.9	5.4	6.1	7.0	7.9	9.1	0.07	<0.001	0.351
Finisher period (day 56 to 111)
ADG, g	1,000	1,001	1,010	1,020	1,045	998	12.7	0.208	0.006
ADFI, kg	2,899	2,912	2,910	2,873	2,958	2,926	26.5	0.254	0.792
G:F, g/kg	345	344	347	355	353	341	3.5	0.818	<0.001
STTD P intake, g/d	5.0	5.7	6.5	7.1	8.3	9.5	0.07	<0.001	0.842
STTD P intake, g/kg gain	5.0	5.7	6.4	7.1	7.9	9.4	0.09	<0.001	0.063
Overall period (day 0 to 111)
ADG, g	941	955	956	975	986	956	6.3	0.001	<0.001
ADFI, g	2,374	2,407	2,401	2,417	2,456	2,415	23.2	0.033	0.102
G:F, g/kg	397	397	398	404	401	396	3.2	0.574	0.002
BW, kg
Day 0	24.2	24.1	24.2	24.2	24.1	24.2	0.73	0.992	0.954
Day 56	73.8	75.1	75.0	76.7	77.0	75.6	1.26	<0.001	<0.001
Day 111	127.9	129.3	130.1	131.9	133.6	129.7	1.12	<0.001	<0.001
Carcass characteristics3
HCW, kg	93.0	94.5	94.5	95.4	96.5	93.9	0.72	0.012	<0.001
Carcass ADG, g4	685	698	694	706	712	692	4.6	0.029	<0.001
Carcass G:F, g/kg5	289	290	289	292	290	287	2.4	0.469	0.063
Carcass yield, %	72.8	73.1	72.6	72.3	72.2	72.4	0.24	0.027	0.368
Backfat, mm6,7	19.0	18.4	18.3	18.6	18.0	18.1	—	0.073	0.580
Fat-free lean, %6,7	55.0	55.4	55.4	55.3	55.6	55.5	—	0.097	0.519
Loin depth, mm6,7	64.1	64.7	64.2	64.5	64.7	64.3	—	0.796	0.651

¹A total of 1,130 pigs (337 × 1050, PIC, initially 24.1 kg BW) were used in a 111-d growth trial with 26 to 27 pigs per pen and 7 pens per treatment.

²All treatments contain variable concentrations of STTD P that represent 80%, 90%, 100%, 115%, 130%, and 150% of the NRC (2012) requirement for pigs within phases.

³Eight hundred seventy-seven pigs were transported to a commercial packing plant for processing and data collection (Swift and Company, Worthington, MN).

⁴Carcass average daily gain = overall average daily gain × carcass yield.

⁵Carcass G:F = carcass ADG/overall ADFI.

⁶SEM for backfat were 0.370, 0370, 0.376, 0.373, and 0.367; SEM for % lean were 0.247, 0.247, 0.251, 0.244, 0.249, and 0.245; and SEM for loin depth were 6.17, 6.17, 6.29, 6.08, 6.23 and 6.10 for 80%, 90%, 100%, 115%, 130%, and 150% of the NRC (2012) requirement, respectively.

⁷Adjusted for HCW.