Performance and Carcass Composition of Growing-finishing Pigs Fed Wheat or Corn-based Diets

Abstract

The objective of this experiment was to compare corn and wheat in finishing pig diets in order to determine whether performance, carcass quality, fatty acid composition or fat colour is altered by choice of cereal grain. A total of 126 crossbred pigs were used in this experiment. At the start of the experiment, a portion of the experimental animals were assigned to receive a wheat-based diet formulated using soybean meal as the sole source of supplementary protein. The remainder of the pigs were assigned to a corn-based diet formulated to supply a similar level of lysine (0.65%) and energy (3,300 kcal/kg DE). At two week intervals, a portion of the pigs on the corn-based diet were switched to the wheat-based diet so that a gradient was produced with pigs being fed the corn and wheatbased diets for different proportions of the finishing period ranging from 100% on wheat to 100% on corn. There were no significant differences in the growth rate of pigs fed the two diets (p = 0.834). Pigs fed wheat tended to consume slightly less feed (p = 0.116) and had a significantly improved feed conversion (p = 0.048) compared with pigs fed corn. Choice of cereal did not affect dressing percentage (p = 0.691), carcass value index (p = 0.146), lean yield (p = 0.134), loin fat (p = 0.127) or loin lean (p = 0.217). Fatty acid composition of backfat was unaffected by the cereal grain fed (p>0.05). Total saturated fatty acid content was 33.31% for both corn and wheat fed pigs (p = 0.997) while the polyunsaturated fatty acid content was 12.01% for corn fed pigs and 11.21% for wheat fed pigs (p = 0.257). The polyunsaturated/saturated ratio was 0.36 for pigs fed corn and 0.34 for pigs fed wheat (p = 0.751). Hunter Lab Colour Scores indicated no difference either in the whiteness or yellowness of the fat. In conclusion, wheat can substitute for corn in growingfinishing pig rations without detrimental effects on pig performance. There were no differences in either the fatty acid composition of backfat or in backfat colour indicating that the decision to use wheat vs. corn needs to be made on economic grounds rather than being based on their effects on fat quality.

Characterization of protected designation of origin Italian meat products obtained from heavy pigs fed barley-based diets1

“…Corn contains a higher amount of carotenoids, naturally occurring fat soluble pigments, compared with barley (NRC, 1998), and this could contribute to the deposition of yellow-colored fat that is discriminated against by many consumers (Han et al, 2005). Carr et al (2005) and Opapeju et al (2006) did not find any differences in the fat color of pigs fed a barley-based diet compared with those fed a corn-based diet.…”

Nutritive value of wheat and wheat by-products in pig nutrition: A review

“…It can be expected, however, that dietary inclusion of wDDGS will have minor impact on carcass quality as wDDGS has a lower fat content (Stein and Shurson, 2009) and, due to the parent grain, a better fat quality (Han et al, 2005) when compared to corn DDGS.…”

Effects of wheat source and particle size in meal and pelleted diets on finishing pig growth performance, carcass characteristics, and nutrient digestibility12

“…In numerous studies when diets were balanced for dietary energy and AA, wheat-and corn-based diets produced similar growth performance and carcass characteristics when fed during the nursery phase (Erickson et al, 1980) or the finisher phase (Han et al, 2005). This suggests corn can be replaced with wheat in diet formulation with few or no negative effects on performance.…”