A total of 225 pigs (PIC 327 × 1050, initially 100.1lb) were used in a 92-day study to determine the effects of withdrawing high-fibre diets 19 days before market on growth performance, carcass characteristics, fat quality and intestinal weights of finishing pigs, reported M.D. Asmus and colleagues at Kansas State University in their paper.

Pigs were allotted to 1one of seven dietary treatments (five or six pens per treatment). Treatments were arranged in a 2×3 factorial plus control with main effects of added choice white grease (CWG; 0 or three per cent) during the withdrawal period (days 73 to 92) and fibre levels of low (corn-soybean meal diet), medium (9.5 per cent wheat middlings [midds] and 15 per cent dried distillers grains with solubles [DDGS]) or high (19 per cent midds and 30 per cent DDGS) during the withdrawal period.

Pigs were fed high-fibre (19 per cent midds and 30 per cent DDGS) diets from days 0 to 73. Control pigs were fed low-fibre corn-soybean meal diets from days 0 to 92.

No CWG × fibre interactions (P>0.13) occurred except for jowl iodine value, which increased (linear, P<0.03) with increasing DDGS and midds only when CWG was added to the diet during the withdrawal period.

Adding CWG during the withdrawal period (days 73 to 92) improved (P<0.02) average daily gain (1.81 versus 1.94lb per day) and feed:gain ratio (3.46 versus 3.19), leading to an overall (days 0 to 92) improvement (P<0.02) in feed:gain ratio.

Carcass yield and backfat depth increased (linear, P<0.05) when low-fibre diets were fed from days 73 to 92.

Pigs fed high levels of DDGS and midds had increased (P<0.001) jowl iodine value, with a larger increase when CWG was added.

Feeding low levels of DDGS and midds during the withdrawal period decreased (linear, P<0.01) whole intestine weights, mainly due to the reduction (P<0.02) in rinsed stomach and full large intestine weights.

Lowering dietary DDGS and midds during a 19-day withdrawal period increased yield through reduced large intestine weight and content and lowered jowl iodine value.

Asmus added that the addition of CWG improved feed:gain ratio but did not improve carcass characteristics.

Reference

Asmus M.D., J.M. DeRouchey, J.L. Nelssen, M.D. Tokach, S.S. Dritz, R.D. Goodband and T.A. Houser. 2012. Effects of lowering dried distillers grains with solubles and wheat middlings with or without the addition of choice white grease prior to marketing on finishing pig growth performance, carcass characteristics, carcass fat quality, and intestinal weights. Proceedings of the Kansas State University Swine Industry Day 2012, p204-217.

Further Reading You can view the full paper in the proceedings by clicking here. Other papers presented at this conference can be viewed by clicking here.

January 2013