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Effect of rice and other cereal grains on growth performance, pig removal, and antibiotic treatment of weaned pigs under commercial conditions T M Che, V G Perez, M Song and J E Pettigrew J ANIM SCI 2012, 90:4916-4924 doi: 10.2527/jas.2011-4916 originally published online July 24, 2012 The online version of this article, along with updated information and services, is located on the World Wide Web at: http://www.journalofanimalscience.org/content/90/13/4916 www.asas.org Downloaded from www.journalofanimalscience.org at The University of Guelph on February 1, 2013 Effect of rice and other cereal grains on growth performance, pig removal, and antibiotic treatment of weaned pigs under commercial conditions1 T M Che,2,3 V G Perez,4 M Song, and J E Pettigrew Department of Animal Sciences, University of Illinois, Urbana 61801 ABSTRACT: Three experiments were conducted to evaluate effects of rice and other cereal grains on growth performance and health of weanling pigs Pigs (1,008 in Exp and and 1,004 in Exp 2; 21 d old) with an initial BW of 5.8 ± 1.0 kg were used Pigs in each experiment were divided into BW blocks (heavy, medium, or light) in each of rooms, resulting in 12 blocks per experiment Each pen within a block had 20 or 21 pigs and equal sex distribution Pens were allotted to dietary treatments in a randomized complete block design Pigs were fed in a 4-phase feeding program with Phases and of wk each and Phases and of wk each Diets were formulated to meet the same nutritional standards within each phase In Exp 1, effects of different cereal grains on pig performance and removal rate (mortality plus morbidity) were investigated Pigs were fed diets based on corn, barley, rolled oats, or rice as the only cereal grain Over a 6-wk period, the ADG of pigs fed rice was greater (P < 0.01) than those pigs fed barley but not different from those pigs fed corn or rolled oats Pigs fed corn or rice did not differ in ADFI, which was greater (P < 0.05) than those pigs fed barley The overall removal rate of pigs fed rice or barley was reduced as compared with those pigs fed rolled oats (P < 0.05), and tended to be less than those pigs fed corn (P = 0.075) Experiment was conducted to determine if the benefits observed in Exp could be obtained by feeding rice for less than wk Treatments included rice diets fed for 0, 1, 2, or wk before changing to corn diets All pigs received a common diet during wk and Pig performance and antibiotic treatments did not differ among dietary treatments However, pigs fed rice for 1, 2, or wk had a reduced overall removal rate (P < 0.05) compared with those fed corn Experiment was conducted to investigate if the amount of rice fed in wk could be reduced without reducing pig performance Rice replaced 0, 50, 75, or 100% of corn in Phase diets All pigs received a common diet from wk to No differences in pig performance or antibiotic treatments among dietary treatments were observed However, pigs fed the diet with 100% rice had a reduced (P = 0.055) overall removal rate compared with pigs fed the corn diet Generally, rice and corn improve pig performance as compared with barley Rice can substitute for corn in nursery diets without detriment to pig performance and substantially reduces pig removals, even when fed for only wk immediately after weaning Key words: cereal grains, commercial trial, growth performance, pig removal, rice, weanling pigs © 2012 American Society of Animal Science All rights reserved J Anim Sci 2012.90:4916–4924 doi:10.2527/jas2011-4916 INTRODUCTION 1The authors thank Illinois Council on Food and Agricultural Research (Champaign, IL) and National Pork Board (Des Moines, IA) for their kind support of this research and J Barnes (Department of Animal Sciences, University of Illinois, Urbana) for her help in weighing pigs 2Corresponding author: tungcheminh@yahoo.com 3Present address: Department of Animal Production, Faculty of Animal Science and Veterinary Medicine, Nong Lam University, Ho Chi Minh City, Vietnam 4Present address: Research and Development, ADM Alliance Nutrition Inc., Quincy, IL 62301 Received November 14, 2011 Accepted June 26, 2012 Rice is a staple cereal grain for human consumption and is grown in most tropical and semitropical regions Rice contains more starch and less fiber compared with other cereal grains (Bach Knudsen, 1997; Kim et al., 2007; Vicente et al., 2008) Because of these characteristics, rice might be a good alternative to other cereal grains in diets for nursery pigs Rice-based diets fed to weaned pigs had greater apparent ileal and total tract digestibilities of GE, OM, and fat than corn-based diets (Li et al., 2002; Mateos et al., 2006; Menoyo et 4916 Downloaded from www.journalofanimalscience.org at The University of Guelph on February 1, 2013 4917 Replacement of corn with rice in pig diets al., 2011) However, rice has received relatively little attention as a potential feedstuff for the animal industries, particularly the U.S pig industry Swine diets usually contain a large amount of cereal grains such as corn, barley, wheat, or oat Among these ingredients, corn is the most economical source of nutrients in many parts of the world However, other cereal grains may be considered due to local availability, lower costs, or specific benefits in promoting health or growth performance of young pigs Different cereal grains have different carbohydrate composition, which may affect the health of the digestive tract by altering the substrates for microbial activity Fibrous cereal grains, such as oats, may stimulate the growth of commensal gut flora (Bach Knudsen et al., 1991), resulting in a healthier digestive tract On the contrary, results of several studies indicate benefits of rice, which has a very low concentration of fiber (Montagne et al., 2003; Hopwood et al., 2004; Lindecrona et al., 2004) The objectives of experiments were 1) to determine if feeding corn, barley, rolled oats, or rice as the main energy sources in the nursery pig diets for wk postweaning affects growth performance and pig removal and 2) to examine if the amount of rice to be used in nursery diets can be reduced without affecting growth performance, pig removal, and the number of needed antibiotic treatments of weanling pigs MATERIALS AND METHODS All experimental protocols in this study were approved by the University of Illinois Institutional Animal Care and Use Committee Three experiments were conducted at a commercial pig farm that is equipped to support research Experimental Design, Animals, and Housing A total of 1,008 crossbred pigs [PIC (Hendersonville, TN) × Monsanto (West Des Moines, IA)] were used in each experiment, except in Exp 2, which had 1,004 pigs Each of rooms at the farm had individual pen feeders and nipple drinkers and bulk bins There were 12 pens in each room and a pen measured 1.8 by 3.0 m in size About 275 pigs were placed in each of rooms and divided into groups by BW block (heavy, medium, or light) Each room was environmentally controlled Individual pigs from the heavy group were placed rotationally into the pens (20 or 21 pigs per pen) designated for the heavy BW block Pigs were exchanged among those pens to ensure the same number of gilts and barrows in each pen Then, the process of pig allotments was repeated for the medium and light pigs All pigs not needed were moved to pens not used in the experiment Once sorted into pens within a room, all pigs designated for research were weighed by pen to obtain initial BW After weighing, some pigs were exchanged among pens to ensure the BW difference between any pens within a block was less than 5% of the mean Pens in which pigs were exchanged were reweighed Pens within a block (similar in BW, sex distribution, and pig number) were allotted to dietary treatments in a randomized complete block design Experimental Diets and Animal Feeding Diets were formulated to contain levels of all essential nutrients that met or exceeded the nutritional requirements of pigs (NRC, 1998) during the nursery period and to have constant levels of ME and standardized ileal digestible Lys and other AA Commercially available raw, broken, white rice was purchased as a commodity and used for rice diets Pigs were fed according to a 4-phase feeding program with Phases and of wk each and Phases and of wk each Phase and diets in Exp were in pellet form, but in Exp and 3, Phase and diets were provided as crumbles whereas Phase and diets in all experiments were in meal form Pigs had ad libitum access to feed and water at all times In Exp 1, pigs (21 d old; 6.0 ± 1.3 kg BW) were allotted to dietary treatments in which corn, barley, rolled oats, or rice was the only cereal grain The analyzed nutrient composition of these cereal grains is presented in Table and the ingredient and chemical composition of the experimental diets is shown in Table To evaluate effects of different cereal grains on pig removal, diets used in this experiment did not contain antibiotic growth promoters or zinc oxide at pharmacological levels Experiment was conducted to confirm the benefits of including rice in diets for weanling pigs that were observed in Exp and to determine if the benefit may be realized if rice is fed for less than wk In Exp 2, pigs (21 d old; 5.5 ± 0.8 kg BW) were allotted to dietary treatments that included rice diets fed for 0, 1, 2, or wk before changing to a corn diet All pigs received a common diet during wk and The ingredient and chemical composition of the experimental diets is shown in Table and the analyzed nutrient composition of corn and rice Table Analyzed chemical composition of the cereal grains used in Exp (as-fed basis)1 Item, % Corn Barley Rolled oats Rice DM CP Crude fat Ash ADF NDF 87.03 6.74 3.56 1.06 2.3 6.7 87.18 11.66 1.67 2.15 4.9 14.7 87.42 14.34 5.52 1.82 2.4 6.6 86.22 7.44 0.72 0.49 0.6 0.6 1Analyzed in duplicate Downloaded from www.journalofanimalscience.org at The University of Guelph on February 1, 2013 4918 Che et al Table Composition of diets used in Exp (as-fed basis) Phase Item Ingredient, % Cereal grains Dried whey Soybean meal, dehulled (48% CP) Corn Barley RO1 Phase Rice Corn Barley Phase RO Rice Corn Barley RO Phase Rice Corn Barley RO Rice 37.15 36.92 42.16 39.68 43.00 41.81 48.82 45.92 51.91 51.86 59.40 55.56 63.43 61.36 68.15 67.18 22.00 22.00 22.00 22.00 16.00 16.00 16.00 16.00 11.48 11.48 11.48 11.48 – – – – 10.00 10.00 10.00 10.00 18.00 18.00 18.00 18.00 24.00 24.00 24.00 24.00 28.01 28.00 28.00 29.08 Spray-dried animal plasma2 8.00 8.00 8.00 8.00 4.00 4.00 4.00 4.00 – – – – – – – – Soy protein concentrate3 5.00 4.11 5.00 2.34 5.00 0.47 5.00 4.67 3.00 5.47 3.00 5.10 3.00 1.25 3.00 6.12 – 6.00 – 3.05 – 0.21 – 6.57 – – – – – – – – 3.93 7.58 0.84 0.66 0.35 0.20 0.06 0.11 0.01 5.51 7.58 0.85 1.00 0.35 0.20 0.09 0.14 0.02 1.79 7.58 0.99 1.17 0.35 0.20 0.12 0.14 0.03 1.00 7.58 0.75 0.65 0.35 0.20 0.02 0.09 0.01 3.90 4.24 0.56 0.93 0.35 0.20 0.16 0.10 0.09 5.50 4.24 0.49 1.07 0.35 0.20 0.10 0.07 0.07 1.43 4.24 0.73 1.52 0.35 0.20 0.23 0.11 0.12 0.50 4.24 0.46 0.91 0.35 0.20 0.11 0.09 0.10 4.59 – 0.56 0.47 0.35 0.20 0.22 0.08 0.14 6.87 – 0.60 1.03 0.35 0.20 0.29 0.10 0.17 1.67 – 0.80 1.30 0.35 0.20 0.33 0.07 0.19 0.50 – 0.44 0.49 0.35 0.20 0.17 0.08 0.16 5.30 – 0.82 1.33 0.35 0.20 0.32 0.08 0.16 7.59 – 0.68 1.47 0.35 0.20 0.20 0.03 0.12 1.14 – 0.75 1.27 0.35 0.20 0.08 – 0.06 0.50 – 0.70 1.46 0.35 0.20 0.27 0.08 0.18 3.52 3.52 3.52 3.52 3.49 3.49 3.49 3.49 3.51 3.51 3.51 3.51 3.53 3.53 3.53 3.53 0.87 0.87 0.87 0.87 0.87 0.91 0.87 0.87 1.45 1.45 1.45 1.45 1.45 1.45 1.45 1.45 0.41 0.41 0.41 0.41 0.43 0.41 0.41 0.44 0.94 0.94 0.94 0.94 0.94 0.94 0.94 0.94 0.29 0.29 0.30 0.29 0.27 0.29 0.28 0.28 1.10 1.11 1.12 1.10 1.03 1.08 1.05 1.04 0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.55 0.55 0.55 0.55 0.55 0.55 0.55 0.55 21.00 21.00 21.00 21.00 14.00 14.00 14.00 14.00 0.79 1.30 0.42 0.84 0.23 0.88 0.80 0.40 7.00 0.78 1.30 0.41 0.84 0.24 0.88 0.80 0.40 7.00 0.78 1.30 0.36 0.84 0.24 0.89 0.80 0.40 7.00 0.79 1.30 0.44 0.84 0.24 0.88 0.80 0.40 7.00 0.70 1.15 0.35 0.75 0.21 0.78 0.80 0.40 – 0.76 1.15 0.32 0.75 0.24 0.87 0.80 0.40 – 0.83 1.15 0.33 0.75 0.26 0.96 0.80 0.40 – 0.69 1.15 0.37 0.75 0.23 0.78 0.80 0.40 – Fish meal, select Menhaden Soybean oil Lactose Limestone Dicalcium phosphate Mineral premix4 Vitamin premix5 L-Lys HCl, 78.8% DL-Met, 99.0% L-Thr, 98.5% Calculated composition6 ME, Mcal/kg SID7 indispensable AA, % Ile Lys Met Thr Trp Val Ca, % Available P, % Lactose, % 1RO = rolled oats diet (APC, Inc, Ankeny, IA) 3Soycomil (Archer Daniels Midland Company, Decatur, IL) 4Provided as milligrams per kilogram of diet: sodium chloride, 3,000; Zn, 100 from zinc oxide; Fe, 90 from iron sulfate; Mn, 20 from manganese oxide; Cu, from copper sulfate; I, 0.35 from calcium iodide; Se, 0.30 from sodium selenite 5Provided per kilogram of diet: retinyl acetate, 2,273 μg; cholecalciferol, 17 μg; DL-α-tocopheryl acetate, 88 mg; menadione sodium bisulfite complex, mg; niacin, 33 mg; D-Ca-pantothenate, 24 mg; riboflavin, mg; vitamin B12, 35 μg; and choline chloride, 324 mg 6NRC, 1998 (for all ingredients except soybean meal); Illini SAND Soy in Animal Nutrition Databases (for soybean meal; Kusina et al., 2007) 7SID = standardized ileal digestible 2Appetein diets is presented in Table Because of increased removal rates observed in Exp 1, all diets used in Exp contained 55 mg/kg of carbadox (Mecadox 2.5; Phibro Animal Health, Fairfield, NJ) and 4,200 mg/kg of zinc oxide in addition to the zinc oxide provide by the micromineral premix Experiment was conducted to examine the benefit of rice vs corn observed in the previous experiments and to determine if the amount of rice used could be reduced compared with that used in Exp Pigs were weaned at about 21 d of age with an average initial BW of 5.9 ± 1.0 kg In the treatment diets, rice replaced 0, 50, 75, or 100% of corn in Phase The ingredient and chemical composition of the Phase diets is shown in Table All pigs received common corn-based diets from Phase to (wk through postweaning) as presented in Table All diets also contained 55 mg/kg of carbadox (Mecadox 2.5; Phibro Animal Health) and 4,200 mg/kg of zinc oxide in addition to the zinc oxide provide by the micromineral premix Feed Sample Analyses Feed samples were ground to pass through a 2-mm screen before analysis Cereal grains used in Exp were analyzed in duplicate for DM (Method 934.01; Downloaded from www.journalofanimalscience.org at The University of Guelph on February 1, 2013 4919 Replacement of corn with rice in pig diets Table Composition of corn and rice diets used in Exp (as-fed basis) Phase Item Ingredient, % Corn Rice Dried whey Soybean meal, dehulled (48% CP) Spray-dried animal plasma Soy protein concentrate Fish meal, Select Menhaden Soybean oil Choice white grease Lactose Limestone Dicalcium phosphate Monocalcium phosphate Carbadox premix3 Zinc oxide Mineral premix4 Vitamin premix5 L-Lys HCl, 78.8% DL-Met, 99.0% L-Thr, 98.5% Calculated composition6 ME, Mcal/kg SID7 indispensable AA, % Ile Lys Met Thr Trp Val Ca, % Available P, % Lactose, % Phase Phase Phase Corn Rice Corn Rice Corn Rice Corn 38.10 – 22.00 10.00 8.00 5.00 4.01 3.61 – 5.60 0.85 0.67 – 1.00 0.42 0.35 0.20 0.07 0.11 0.01 – 37.34 22.00 10.00 8.00 5.00 4.33 4.11 – 5.60 0.77 0.70 – 1.00 0.42 0.35 0.20 0.04 0.12 0.02 42.82 – 16.00 18.00 4.00 3.00 5.49 4.09 – 2.80 0.56 0.92 – 1.00 0.42 0.35 0.20 0.16 0.10 0.09 – 41.91 16.00 18.00 4.00 3.00 5.86 4.65 – 2.80 0.47 0.95 – 1.00 0.42 0.35 0.20 0.14 0.14 0.11 53.95 – 10.00 24.00 – – 6.12 2.68 – – 0.55 0.50 – 1.00 0.21 0.35 0.20 0.22 0.08 0.14 – 52.48 10.00 24.00 – – 6.38 3.77 – – 0.58 0.51 – 1.00 0.21 0.35 0.20 0.20 0.14 0.18 63.67 – – 27.97 – – – – 4.47 – 1.11 – 1.17 0.50 – 0.35 0.20 0.32 0.08 0.16 3.45 3.45 3.45 3.45 3.45 3.45 3.45 0.87 1.45 0.41 0.94 0.29 1.10 0.90 0.55 21.00 0.87 1.45 0.41 0.94 0.30 1.10 0.90 0.55 21.00 0.87 1.45 0.43 0.94 0.27 1.03 0.90 0.55 14.00 0.87 1.45 0.47 0.94 0.28 1.03 0.90 0.55 14.00 0.78 1.30 0.42 0.84 0.23 0.89 0.80 0.40 7.00 0.78 1.30 0.47 0.84 0.24 0.88 0.80 0.40 7.00 0.69 1.15 0.35 0.75 0.21 0.78 0.80 0.40 – 1Appetein, APC, Inc (Ankeny, IA) (Archer Daniels Midland Company, Decatur, IL) 3Mecadox 2.5, provided 0.055 g of carbadox per kilogram of diet (Phibro Animal Health, Fairfield, NJ) 4Provided as milligrams per kilogram of diet: sodium chloride, 3,000; Zn, 100 from zinc oxide; Fe, 90 from iron sulfate; Mn, 20 from manganese oxide; Cu, from copper sulfate; I, 0.35 from calcium iodide; and Se, 0.30 from sodium selenite 5Provided per kilogram of diet: retinyl acetate, 2,273 μg; cholecalciferol, 17 μg; DL-α-tocopheryl acetate, 88 mg; menadione sodium bisulfite complex, mg; niacin, 33 mg; D-Ca-pantothenate, 24 mg; riboflavin, mg; vitamin B12, 35 μg; and choline chloride, 324 mg 6NRC, 1998 (for all ingredients except soybean meal; Illini SAND Soy in Animal Nutrition Databases (for soybean meal; Kusina et al., 2007) 7SID = standardized ileal digestible 2Soycomil AOAC Int., 2005), CP (Method 990.03; AOAC Int., 2005), crude fat (Method 920.39; AOAC Int., 2005), ash (Method 942.05; AOAC Int., 2005), ADF (Method 973.18; AOAC Int., 2005), and NDF (Ankom Method 6; Eurofins, Des Moines, IA) Corn and rice diets in Exp were analyzed for DM, CP, crude fat, ash, and ADF as described for Exp These diets were also analyzed for NDF (Holst, 1973), total dietary fiber (Method 985.29; AOAC Int., 2005), and AA [Method 982.30 E (a, b, c); AOAC Int., 2005] Measurement of Pig Performance, Removal Rate, and Antibiotic Treatment The initial BW of pigs in each pen was recorded at the commencement of the experiment Subsequent pen weights and feed disappearance measurements were determined at d 7, 14, 28, and 42 postweaning The ADG, ADFI, and G:F were calculated on a per-pen basis The number of pigs removed from each pen because of mortality or morbidity was recorded daily to calculate the removal rate Removal of pigs was done by the farm Downloaded from www.journalofanimalscience.org at The University of Guelph on February 1, 2013 4920 Che et al Table Analyzed nutrient composition of corn and rice diets used in Exp (as-fed basis)1 Phase Item Corn Rice Phase Corn Rice Phase Corn Rice Phase Corn DM 89.62 89.59 88.81 89.56 87.66 88.70 88.40 CP 22.37 22.24 22.32 22.61 20.95 21.56 20.09 Crude fat 5.50 4.76 5.98 5.67 4.94 4.21 6.64 Total dietary fiber 7.93 4.16 8.28 4.30 8.27 4.61 10.34 NDF 16.65 6.41 14.14 6.73 20.1 10.73 42.59 ADF 2.29 1.46 2.56 1.81 2.41 1.78 2.79 Ash 7.12 6.40 6.81 6.58 6.01 5.48 5.11 Indispensable AA, % Arg 1.27 1.40 1.32 1.44 1.32 1.41 1.30 His 0.59 0.58 0.57 0.56 0.54 0.50 0.52 Ile 0.94 0.99 0.95 1.00 0.93 0.93 0.87 Leu 2.02 1.93 1.91 1.82 1.81 1.63 1.70 Lys 1.53 1.49 1.46 1.46 1.45 1.42 1.37 Met 0.44 0.45 0.44 0.48 0.43 0.53 0.37 Phe 1.04 1.06 1.01 1.03 0.96 0.93 0.95 Thr 1.05 1.03 1.03 1.01 0.94 0.97 0.87 Trp 0.33 0.32 0.30 0.30 0.24 0.26 0.25 Val 1.29 1.32 1.16 1.25 1.04 1.09 0.98 1Analyzed in duplicate crew according to standard protocols for the farm If pigs were determined to be runts, they were culled The number of antibiotic treatments per pen was also recorded daily in Exp and but not in Exp During the experimental period, several antibiotics were used for disease treatments [Ceftiofur, 5.0 mg/kg BW (Pharmacia and Upjohn Co., NY); Penicillin G Procaine, 6,000 units/kg BW (Durvet Inc., Blue Springs, MO); and Tylosin, 8.0 mg/kg BW (Elanco Animal Health, Indianapolis, IN)] The production system had experienced an acute outbreak of porcine reproductive and respiratory syndrome in sow farms that supplied this nursery shortly before these experiments were conducted There was also an active enteric infection that was diagnosed as caused by Escherichia coli in Exp.1 and by Salmonella in Exp and Statistical Analysis Data were analyzed as a randomized complete block design by ANOVA using the MIXED procedure (SAS Inst Inc., Cary, NC) The pen was considered the experimental unit There were rooms and BW blocks (heavy, medium, and light) in each of the rooms, resulting in 12 blocks per experiment Blocks were considered random effects Treatment differences were compared using the least squares means with a Tukey adjustment Pig removals and number of antibiotic treatments were compared by χ2 analysis Treatment effects were considered significant at P ≤ 0.05 whereas a trend for a treatment effect was noted when P < 0.10 Table Composition of Phase diets used in Exp (as-fed basis) Item Rice-0% Rice-50% Rice-75% Rice-100% Ingredient, % Corn Rice Dried whey Soybean meal, dehulled (48% CP) Spray-dried animal plasma1 Soy protein concentrate2 Fish meal, Select Menhaden Soybean oil Lactose Limestone Dicalcium phosphate Carbadox premix3 Zinc oxide Mineral premix4 Vitamin premix5 L-Lys HCl, 78.8% DL-Met, 99.0% L-Thr, 98.5% Calculated composition6 ME, Mcal/kg SID7 indispensable AA, % Ile Lys Met Thr Trp Val Ca, % Available P, % Lactose, % 38.10 – 22.00 10.00 19.06 18.67 22.00 10.00 9.53 28.00 22.00 10.00 – 37.34 22.00 10.00 8.00 5.00 4.01 3.61 5.60 0.85 0.67 1.00 0.42 0.35 8.00 5.00 4.17 3.86 5.60 0.81 0.69 1.00 0.42 0.35 8.00 5.00 4.25 3.98 5.60 0.79 0.69 1.00 0.42 0.35 8.00 5.00 4.33 4.11 5.60 0.77 0.70 1.00 0.42 0.35 0.20 0.07 0.11 0.01 0.20 0.05 0.11 0.01 0.20 0.05 0.12 0.02 0.20 0.04 0.12 0.02 3.45 3.45 3.45 3.45 0.87 1.45 0.41 0.94 0.29 1.10 0.90 0.55 21.00 0.87 1.45 0.41 0.94 0.30 1.10 0.90 0.55 21.00 0.87 1.45 0.41 0.94 0.29 1.11 0.90 0.55 21.00 0.87 1.45 0.41 0.94 0.29 1.10 0.90 0.55 21.00 1Appetein, APC, Inc (Ankeny, IA) (Archer Daniels Midland Company, Decatur, IL) 3Mecadox 2.5, provided 0.055 g of carbadox per kilogram of diet (Phibro Animal Health, Fairfield, NJ) 4Provided as milligrams per kilogram of diet: sodium chloride, 3,000; Zn, 100 from zinc oxide; Fe, 90 from iron sulfate; Mn, 20 from manganese oxide; Cu, from copper sulfate; I, 0.35 from calcium iodide; and Se, 0.30 from sodium selenite 5Provided per kilogram of diet: retinyl acetate, 2,273 μg; cholecalciferol, 17 μg; DL-α-tocopheryl acetate, 88 mg; menadione sodium bisulfite complex, mg; niacin, 33 mg; D-Ca-pantothenate, 24 mg; riboflavin, mg; vitamin B12, 35 μg; and choline chloride, 324 mg 6NRC, 1998 (for all ingredients except soybean meal); Illini SAND Soy in Animal Nutrition Databases (for soybean meal; Kusina et al., 2007) 7SID = standardized ileal digestible 2Soycomil RESULTS Experiment From d to postweaning, pigs fed corn had a greater ADG than those fed barley (P < 0.05) or rice (P < 0.01; Table 6) Similarly, pigs fed corn consumed more feed than those fed barley (P < 0.05) or rice (P < 0.001) The ADFI of pigs fed rolled oats was also greater than Downloaded from www.journalofanimalscience.org at The University of Guelph on February 1, 2013 Replacement of corn with rice in pig diets Table Effects of different cereal grains on growth performance of pigs during wk postweaning (Exp 1) Dietary treatments1 Item Corn d to ADG, g ADFI, g G:F, g/kg d to 14 ADG, g ADFI, g G:F, g/kg d 14 to 28 ADG, g ADFI, g G:F, g/kg d 28 to 42 ADG, g ADFI, g G:F, g/kg d to 42 ADG, g ADFI, g G:F, g/kg Barley Rolled oats Rice SED P-value 125a 146a 861 102b 127bc 810 117ab 139ab 841 98b 120c 824 31 0.002