Feed Efficiency of Gestating Gilts and Sows Under Commercial Conditions

A study was conducted on a commercial sow farm to examine the effects of parity and stage of gestation on ADG and G:F of gestating sows. A total of 712 females (Line 1050, PIC, Hendersonville, TN) were group-housed and individually fed with electronic sow feeders. Individual scales were in the alleyway after individual feeding stations leading to the pen. Females were moved from the breeding stall to the pens on d 4 of gestation. Feed intake and BW were recorded daily throughout gestation. As a result, ADFI, ADG, and G:F were generated daily for each sow. Gilts (parity 1) and sows received 2.0 and 2.26 kg/day, respectively, of feed while 12 thin females received 3.0 kg/day (fed a common diet with 0.63% SID Lys and 3225.3 kcal/kg intake of ME). Data was divided into 3 parity groups: 1, 2, and 3+ and gestation was divided into 5 periods: d 4-15, d 16-30, d 31-60, d 61-90, and d 91-112.

From d 4 to 15, ADFI and ADG were lowest for each parity group compared to the other periods of gestation (P<0.001). For parity 1 sows, ADFI was lower (P<0.05) compared to parity 2 and 3+ sows, which is attributed to the assigned feeding strategies. Parity 2 sows, although provided the same feed allowance, had greater ADFI during the first period (P<0.05) than parity 3+ sows. Both parity and period of gestation affected (P<0.05) ADG. Gain: feed was lowest from d 4-15 for each parity group (P<0.001). Parity influenced (P<0.05) G:F with parity 1 sows having the greatest G:F in most gestation periods. Overall, this study shows that gestation ADFI, ADG, and G:F differ based on parity and period of gestation.

	Gestation, d
	4-15	16-30	31-60	61-90	91-112	SEM
ADFI, kg
Parity 1	1.79ax	1.98bx	1.96bx	1.97bx	1.96bx	0.007
Parity 2	2.16az	2.25by	2.26by	2.25by	2.24by	0.009
Parity 3+	2.10ay	2.25by	2.27by	2.27by	2.27by	0.007
ADG, kg
Parity 1	0.38ay	0.71bz	0.68bz	0.67bz	0.66by	0.017
Parity 2	0.20ax	0.58dy	0.43bx	0.49bcy	0.53cdx	0.020
Parity 3+	0.23ax	0.42bx	0.49cy	0.42bx	0.75dz	0.016
G:F
Parity 1	0.21ay	0.36bz	0.34by	0.34bz	0.34by	0.008
Parity 2	0.10ax	0.26dy	0.19bx	0.22bcy	0.24cdx	0.010
Parity 3+	0.12ax	0.19bx	0.21bx	0.18bx	0.33cy	0.008
Values with different superscripts within a rowabcd or columnxyz differ, P<0.05.