Effects of withdrawing high-fiber ingredients prior to market on finishing pig growth performance, carcass characteristics, intestinal weights, and carcass fat quality

Abstract Text:

A total of 288 pigs (initially 38.4 kg) were used in an 88-d study to determine the timing of high-fiber ingredient removal from the diet prior to marketing to optimize growth performance, carcass characteristics (yield), and carcass fatty acid composition. Two diet types were used: (1) corn-soybean meal control diet (9.3% NDF) and (2) high-fiber diet (19% NDF) containing 30% dried distillers grains with solubles (DDGS) and 19% wheat middlings. Pens of pigs were randomly allotted to 1 of 6 dietary feeding strategies with 8 pigs per pen and 6 replications per treatment. The 6 strategies consisted of the corn-soy control or high-fiber diet fed throughout, or the high-fiber diet fed 20, 15, 10, or 5 d prior to harvest, after which pigs were switched to the control diet. Diets were not balanced for energy. Overall, pigs continuously fed the high-fiber diet tended (P<0.07) to have increased ADFI and decreased (P<0.01) G:F compared to pigs fed the control diet. Withdrawal strategy did not significantly influence growth performance. Carcass yield decreased (P<0.01) in pigs fed the high-fiber diet compared with those fed the control and increased (quadratic; P<0.03) as days of withdrawal increased. Jowl iodine value (IV) increased (P<0.01) in pigs fed the high-fiber diet compared with those fed the control and decreased (linear; P<0.01) as withdraw time increased (due to reduction in DDGS prior to market).  Pigs continuously fed the high-fiber diet had heavier (P<0.01) full large intestine weight than pigs fed the control. Full large intestine weight decreased (linear; P<0.02) as withdrawal time increased. In summary, pigs fed the high-fiber diet had decreased G:F and carcass yield and switching pigs to a corn-soy diet restored carcass yield when done for the last 15 to 20 d prior to harvest.

 

											Probability,   P <
		High-fiber   withdrawal prior to market, d									Control vs.	Duration
Item	Control	20		15		10		5	0		0 withdrawal	Linear	Quad
ADG, kg	1.00	0.98		1.00		0.99		0.99	0.99		0.61	0.71	0.65
ADFI, kg	2.79	2.85		2.93		2.92		2.95	2.90		0.07	0.33	0.20
G:F	0.348	0.340		0.340		0.339		0.336	0.335		0.01	0.29	0.15
HCW, kg	92.2	91.1		91.4		91.0		90.7	89.3		0.11	0.29	0.47
Yield, %	72.7	72.5		72.5		72.2		72.0	71.1		0.01	0.01	0.03
Jowl IV	66.8	72.6		73.3		73.2		73.8	74.5		0.01	0.01	0.65

¹SEM was 0.014, 0.043, 0.003, 1.31, 0.201, and 0.350, respectively.

Keywords: finishing pig, withdrawal, yield