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Anise oil (AO) is a phytochemical with antibiotic properties and it reduces the growth of Clostridium perfringens in vitro, which is the main causal agent of necrotic enteritis. A series of battery experiments was conducted to determine an AO dosage to feed to broilers and its effect during 2 C. perfringens challenges, and a floor pen experiment to determine its effect in performance. Anise oil linearly reduced (P 0.05) during Experiment 3. In both challenges, the jejunum of broilers fed AO had fewer and milder (P 0.10) growth performance for the entire trial. Broilers fed PC or AO had greater ADG (P 0.10) among broilers fed any of the dietary treatments. Residues of AO were not present at detectable levels in breast meat.

Anise oil (AO) was fed to lactating sows and to pigs after weaning to determine its effect on feed intake and performance of nursery pigs. Sows (24) were fed either (1) control or (2) AO (control + 50 mg/kg of AO). At weaning, within sow treatment, 168 pigs were assigned to control or AO. Pigs were fed a 3-phase nursery program (1 wk each), and feed intake was determined daily during wk 1. On d 2, 3, or 7, daily feed intake tended to be greater for progeny of sows fed AO (P < 0.10). Pigs fed AO also tended to consume more feed on d 1, 5, and 7 (P < 0.10). On d 7 and phase 1, progeny of sows fed control tended to have the least ADFI when fed control and the highest when fed AO (P < 0.10). Pigs fed AO had greater ADFI, ADG, and G:F (P < 0.05) in wk 2. In wk 3, progeny of sows fed control had the least ADFI when fed control and the highest when fed AO (P < 0.05). Overall, progeny of sows fed control tended to have the least ADFI when fed control and greatest when fed AO (P = 0.06). Pigs fed AO during the nursery phase tended to have greater ADG and BW (P < 0.10). Feeding AO did not affect sow performance but increased ADFI in pigs immediately after weaning.

The survey purpose was to determine the state and regional macromineral status of Louisiana beef cow/calf production systems. Serum, forage, soil, and water were sampled from fall 2007 to spring 2009 at Louisiana beef-cattle operations (n = 25), which were divided into 7 regions (northwest, northeast, central, southwest, south central, Florida parishes, and southeast). Serum samples were collected twice annually in fall and spring, forage samples were collected quarterly, and soil and water were collected annually. The forage concentrations of Ca (0.42%); serum concentrations of Ca, Mg, Na, and S (9.0, 1.9, 303.3, and 103.3 mg/100 mL, respectively); soil concentrations of P, Na, and S (56.3, 88.4, and 29.7 mg/kg, respectively); and water concentrations of Na (84.7 mg/kg) were not different (P > 0.05) among regions. For all serum samples, less than 10% of Ca, 57% of Mg, and 14% of Na were less than reported lower critical levels in serum; 40% of Ca, 45% of P, small percentage of K, 70% of Na, and 7% of S were less than the minimum reported for appropriate nutrition in forage for beef cattle. All macromineral concentrations were above critical levels in soil as required for adequate plant growth. Water Na concentrations in regions northeast, southwest, south central, and Florida parishes were at desirable levels reported for livestock. Using serum as an indicator, the results indicated Louisiana cattle maintained adequate macromineral status and perhaps are partially reflective of the macromineral supplementation programs used throughout the state.

Three experiments were conducted to determine the Val and Ile requirements in low-CP, corn-soybean meal (C-SBM) AA-supplemented diets for 20- to 45-kg pigs. All experiments were conducted for 26 to 27 d with purebred or crossbred barrows and gilts, which were blocked by initial BW. Treatments were replicated with 5 or 6 pens of 3 or 4 pigs per pen. At the beginning of Exp. 1 and the end of all experiments, blood samples were obtained from all pigs to determine plasma urea N (PUN) concentrations. All diets were C-SBM with 0.335% supplemental Lys to achieve 0.83% standardized ileal digestible (SID) Lys, which is the Lys requirement of these pigs. In Exp. 1, 0, 0.02, 0.04, 0.06, 0.08, or 0.10% L-Val was supplemented to achieve 0.51, 0.53, 0.55, 0.57, 0.59, or 0.61% dietary SID Val, and Thr, Trp, Met, and Ile were supplemented to maintain Thr:Lys, Trp:Lys, TSAA:Lys, and Ile:Lys ratios of 0.71, 0.20, 0.62, and 0.60, respectively. Also, supplemental Gly and Glu were added to all diets to achieve 1.66% Gly + Ser and 3.28% Glu, which is equal to the Gly + Ser and Glu content of a previously validated positive control diet that contained no supplemental AA. Treatment differences were considered significant at P < 0.10. Valine addition increased ADG, ADFI, and G:F in pigs fed 0.51 to 0.59% SID Val (linear, P < 0.08), but ADG and ADFI were decreased at 0.61% SID Val (quadratic, P ≤ 0.10). On the basis of ADG and G:F, the SID Val requirement is between 0.56 and 0.58% in a C-SBM diet supplemented with AA. In Exp. 2 and 3, 0, 0.02, 0.04, 0.06, or 0.08% L-Ile was supplemented to achieve 0.43, 0.45, 0.47, 0.49, or 0.51% dietary SID Ile, and Thr, Trp, Met, and Ile were supplemented to maintain Thr:Lys, Trp:Lys, TSAA:Lys, and Val:Lys ratios of 0.71, 0.20, 0.62, and 0.74, respectively. Also, supplemental Gly and Glu were added to achieve 1.66% Gly + Ser and 3.28% Glu as in Exp. 1. Data from Exp. 2 and 3 were combined and analyzed as 1 data set. Daily BW gain, ADFI, and G:F were not affected by Ile additions to the diet; however, ADFI was decreased among pigs fed the diet with 0.45% SID Ile (P < 0.10) compared with pigs fed the 0.43% SID Ile diet. Broken-line analysis requirements could not be estimated for the combined data from Exp. 2 or 3. The results of this research indicate that the SID Val requirement is between 0.56 to 0.58% (0.67 to 0.70 SID Val:Lys), and the Ile requirement is adequate at 0.43% SID Ile (0.52 SID Ile:Lys) for 20- to 45-kg pigs.

The purpose of this investigation was to compare the growth performance of grower pigs fed low-CP, corn-soybean meal (C-SBM) AA-supplemented diets with that of pigs fed a positive control (PC) C-SBM diet with no supplemental Lys. Five experiments were conducted with Yorkshire crossbred pigs, blocked by BW (average initial and final BW were 21 and 41 kg, respectively) and assigned within block to treatment. Each treatment was replicated 4 to 6 times with 4 or 5 pigs per replicate pen. Each experiment lasted 28 d and plasma urea N was determined at the start and end of each experiment. All diets were formulated to contain 0.83% standardized ileal digestible Lys. All the experiments contained PC and negative control (NC) diets. The PC diet contained 18% CP and was supplemented with only DL-Met. The NC diet contained 13% CP and was supplemented with L-Lys, DL-Met, L-Thr, and L-Trp. The NC + Ile + Val diet was supplemented with 0.10% Val + 0.06% Ile. The NC + Ile + Val diet was supplemented with either His (Exp. 1), Cys (Exp. 2), Gly (Exp. 2, 3, and 4), Glu (Exp. 3), Arg (Exp. 4), or combinations of Gly + Arg (Exp. 4 and 5) or Gly + Glu (Exp. 5). Treatment differences were considered significant at P < 0.10. In 3 of the 4 experiments that had PC and NC diets, pigs fed the NC diet had decreased ADG and G:F compared with pigs fed the PC diet. The supplementation of Ile + Val to the NC diet restored ADG in 4 out of 5 experiments. However, G:F was less than in pigs fed the PC diet in 1 experiment and was intermediate between the NC and PC diets in 3 experiments. Pigs fed supplemental Ile + Val + His had decreased G:F compared with pigs fed the PC. Pigs fed supplemental Cys to achieve 50:50 Met:Cys had decreased G:F compared with pigs fed the PC. Pigs fed Ile + Val + 0.224% supplemental Gly had similar ADG, greater ADFI, and decreased G:F compared with pigs fed the PC. Pigs fed Ile + Val + 0.52% supplemental Gly had ADG and G:F similar to that of pigs fed the PC. Pigs fed supplemental Glu had decreased G:F compared with pigs fed the PC. Pigs fed Ile + Val + 0.48% supplemental Arg had decreased G:F compared with pigs fed the PC. Pigs fed the diet supplemented with Gly + Arg had ADG and G:F similar to pigs fed the PC. Pigs fed the low-CP diets had reduced plasma urea N compared with pigs fed PC. The results of these experiments indicate that supplementing Gly or Gly + Arg to a low-CP C-SBM diet with 0.34% Lys, Met, Thr, Trp, Ile, and Val restores growth performance to be similar to that of pigs fed a PC diet with no Lys supplementation.

SUMMARY Any variation in processing soybeans for inclusion in poultry diets requires validation of the ability of the soybean meal to sustain growth performance similar to what is achieved with solvent-extracted soybean meal. Three experiments were conducted to investigate the effect of feeding an expeller-extruded soybean meal vs. a commercial solvent-extracted soybean meal. Growth performance attributable to the source of soybean meal did not differ for 0- to 18-d-old broilers fed 2 levels of Lys (1.0 or 1.3%) and 2 levels of ME (3,000 or 3,300 kcal/kg). Similar growth performance was obtained for broilers fed solvent-extracted soybean meal vs. expellerextruded soybean meal for 0 to 49 d. However, broilers fed the expeller-extruded soybean meal had lower breast meat yield (24.95 vs. 26.30%). True digestibility values determined with adult cecectomized roosters for the expeller-extruded soybean meal indicated digestibility values of 86.6, 83.5, 87.4, 85.5, 86.5, and 86.7 for Lys, Thr, Met, Val, Ile, and Leu, respectively, which are lower than those reported by the NRC for solvent-extracted soybean meal. The feeding value of expeller-extruded soybean meal used in these experiments was similar to that of solventextracted soybean meal; however, consideration must be given to amino acid digestibility to achieve optimal breast meat yield.

Four experiments were conducted to determine the Lys requirement, the maximum amount of supplemental Lys that does not decrease growth performance, and to determine the order of limiting AA beyond Lys, Thr, Trp, and Met in a corn-soybean meal diet for 20- to 45-kg pigs. All experiments were conducted for 27 to 28 d with purebred or crossbred barrows and gilts, which were blocked by initial BW. Treatments were replicated with 4 to 6 pens of 4 to 6 pigs per pen. In all experiments, pigs and feeders were weighed on d 0, 14, and 27 or 28. At the beginning and end of all experiments, blood samples were obtained from all pigs to determine plasma urea N (PUN) concentrations. In Exp. 1, 0.830, 0.872, 0.913, and 0.955% standardized ileal digestible (SID) Lys was fed, whereas 0.747, 0.788, 0.830, 0.872, and 0.913% SID Lys was fed in Exp. 2. Broken-line analysis requirement estimates could not be estimated from any response variable in Exp. 1, but in Exp. 2, using ADG and PUN, the estimated SID Lys requirement was 0.83%. In Exp. 3, 0, 0.118, 0.191, 0.264, and 0.335% supplemental Lys was added to achieve 0.83% SID Lys in all diets, and Thr, Trp, and Met were supplemented to maintain Thr:Lys, Trp:Lys, and TSAA:Lys of 0.65, 0.18, and 0.60, respectively. Based on ADG, ADFI, and G:F, up to 0.23% supplemental Lys can be added along with supplemental Thr, Trp, and Met without negatively affecting growth performance; PUN was linearly decreased (P 0.10) ADG or G:F compared with the NC. The combined addition of Val + Ile resulted in ADG that was intermediate between the PC and NC diets but not different from either diet (P > 0.10); G:F was not improved (P > 0.10) to that observed in pigs fed the PC diet. The PUN was not different (P > 0.10) among pigs fed diets with supplemental AA but less (P < 0.10) than pigs fed the PC. The results of this research indicate that the Lys requirement for 20- to 45-kg pigs is 0.83% SID Lys, up to 0.23% supplemental Lys (0.29% l-Lys·HCl or 0.45% l-Lys·SO(4)) can be added along with supplemental Thr, Trp, and Met without negatively affecting growth performance, and another AA besides Val and Ile may be limiting growth performance in a corn-soybean meal diet with 0.335% supplemental Lys.

SUMMARY The ability of broilers to adapt to a deficiency or excess of nonphytate P (nPP) in the starter phase without any negative effect on growth performance and bone characteristics in subsequent phases has received very little attention. Two experiments were conducted to investigate the effect of feeding marginally deficient or excessive P in the starter phase on growth and bone responses of broilers in subsequent phases. Feeding below the nPP requirement for 0 to 14 d resulted in better adaptation to lower nPP in the later phases, whereas feeding above the nPP requirement for 0 to 21 d resulted in a decrease in FE.

SUMMARY Three experiments were conducted with broilers to determine the level of red blood cells (RBC) that can be included in diets with or without supplemental amino acids without negatively affecting growth performance. The inclusion of up to 6% RBC with the supplementation of Ile and Arg resulted in similar growth performance when compared with broilers fed a corn- and soybean meal-based diet. However, without supplementation of Ile and Arg, only the inclusion levels of 0.5, 1, and 2% RBC resulted in similar growth performance when compared with the control diet.

Two experiments, each consisting of 2 trials, were conducted to determine the effect of salmon protein hydrolysate (SPH) and spray-dried plasma protein (SDPP) fed during the first week postweaning and their subsequent effect on the growth performance of weanling pigs. Pigs were fed in a 3-phase feeding program with durations of 7 d for phase 1 in both Exp. 1 and 2; 14 or 15 d for phase 2 in Exp. 1 and 2, respectively; and 7 or 8 d for phase 3 in Exp. 1 and 2, respectively. Dietary treatments were fed only during phase 1, whereas the same diet was fed to all pigs in phases 2 and 3. Pigs were blocked by initial BW and sex, and littermates were balanced across treatments. Data from the 2 trials within each experiment were combined and analyzed together; no treatment × trial interactions (P > 0.10) were observed. In Exp. 1, a total of 324 weanling pigs (10 replications of 5 or 6 pigs per pen) with an average initial BW of 6.4 ± 1.3 kg were assigned to 1) a control diet with no SPH or SDPP, 2) 1.5% SPH, 3) 3.0% SPH, 4) 1.5% SDPP, 5) 3.0% SDPP, or 6) 1.5% SPH + 1.5% SDPP. Experiment 2 was similar to Exp. 1, but red blood cells were removed from all diets to reduce diet complexity. In Exp. 2, weanling pigs (n = 320, 14 replications of 5 or 6 pigs per pen) with an average initial BW of 5.4 ± 1.2 kg were assigned to 1) a control diet with no SPH or SDPP, 2) 1.5% SPH, 3) 1.5% SDPP, or 4) 1.5% SPH + 1.5% SDPP. Three batches of SPH were used, and each batch was analyzed for AA composition. In Exp. 1, the inclusion of SDPP or SPH during phase 1 did not affect (P > 0.10) ADG, ADFI, or G:F compared with those of pigs fed the control diet. No carryover effects on growth performance were observed in any of the subsequent phases. Overall, G:F was greater (P = 0.08) in pigs fed the 1.5% diets compared with those fed the 3.0% diets. In Exp. 2, no differences (P > 0.10) were observed in ADG, ADFI, or G:F among pigs fed the SPH or SDPP diets compared with those of pigs fed the control diet. Pigs fed the combined diet had greater (P < 0.10) overall ADFI compared with that of pigs fed the control diet, but ADFI was similar to that of pigs fed the SPH and SDPP diets. These results indicate that inclusion of up to 3% SDPP or SPH in diets fed during the first week postweaning did not affect the growth performance of weanling pigs, and no subsequent carryover effects were observed. Salmon protein hydrolysate did not affect the growth performance of weanling pigs and may be considered an alternative protein source in diets for weanling pigs.

Four experiments were conducted to determine the interactive effects of pharmacological amounts of Zn from ZnO and Cu from organic (Cu-AA complex; Cu-AA) or inorganic (CuSO(4)) sources on growth performance of weanling pigs. The Cu was fed for 4 (Exp. 1) or 6 (Exp. 2, 3, and 4) wk after weaning, and Zn was fed for 4 (Exp. 1) or 2 (Exp. 2, 3, and 4) wk after weaning. Treatments were replicated with 7 pens of 5 or 6 pigs per pen (19.0 ± 1.4 d of age and 5.8 ± 0.4 kg of BW, Exp. 1), 12 pens of 21 pigs per pen (about 21 d of age and 5.3 kg of BW, Exp. 2), 5 pens of 4 pigs per pen (20.3 ± 0.5 d of age and 7.0 ± 0.5 kg of BW, Exp. 3), and 16 pens of 21 pigs per pen (about 21 d of age and 5.7 kg of BW, Exp. 4). In Exp. 1 and 2, Cu-AA (0 vs. 100 mg/kg of Cu) and ZnO (0 vs. 3,000 mg/kg of Zn) were used in a 2 × 2 factorial arrangement. Only Exp. 1 used in-feed antibiotic (165 mg of oxytetracycline and 116 mg of neomycin per kilogram feed), and Exp. 2 was conducted at a commercial farm. In Exp. 3, sources of Cu (none; CuSO(4) at 250 mg/kg of Cu; and Cu-AA at 100 mg/kg of Cu) and ZnO (0 vs. 3,000 mg/kg of Zn) were used in a 3 × 2 factorial arrangement. In Exp. 4, treatments were no additional Cu, CuSO(4) at 315 mg/kg of Cu, or Cu-AA at 100 mg/kg of Cu to a diet supplemented with 3,000 mg/kg of Zn from ZnO and in-feed antibiotic (55 mg of carbadox per kilogram of feed). In Exp. 1 and 2, both Zn and Cu-AA improved (P < 0.001 to P = 0.03) ADG and ADFI. No interactions were observed, except in wk 1 of Exp. 2, where Zn increased the G:F only in the absence of Cu-AA (Cu-AA × Zn, P = 0.04). A naturally occurring colibacillosis diarrhea outbreak occurred during this experiment. The ZnO addition reduced (P < 0.001) the number of pigs removed and pig-days on antibiotic therapy. In Exp 3, ADFI in wk 2 was improved by Zn and Cu (P < 0.001 and P = 0.09, respectively) with no interactions. In wk 1, G:F was reduced by ZnO only in the absence of Cu (Cu × Zn, P = 0.03). Feeding Zn decreased fecal microbiota diversity in the presence of CuSO(4) but increased it in the presence of Cu-AA (Cu source × Zn, P = 0.06). In Exp. 4, Cu supplementation improved the overall ADG (P = 0.002) and G:F (P < 0.001). The CuSO(4) effect on G:F was greater (P < 0.001) than the Cu-AA effect. Our results indicate that pharmacological amounts of ZnO and Cu (Cu-AA or CuSO(4)) are additive in promoting growth of pigs after weaning.

Dried blood cells (DBC) contain low levels of Ile relative to Lys, and thus Ile may become limiting in pig diets supplemented with DBC. Therefore, 3 experiments were conducted to evaluate the effect of increasing DBC in corn-soybean meal–based diets in weanling (7 to 13 kg, Exp. 1 and 2) and grower (24 to 46 kg, Exp. 3) pigs. Treatments were replicated with 4 to 6 pens of 4 to 6 pigs per pen. In Exp. 1 and 2 (14 d), all diets contained 0.10% l-Lys·HCl and DBC were added at 2% increments from 0 to 8%. In Exp. 1, all diets contained 1.40% total dietary Lys. All diets in Exp. 2 contained 1.185% apparent ileal digestible Lys. In Exp. 1, increasing dietary DBC resulted in a linear decrease in ADFI (P 0.10). In Exp. 2, increasing dietary DBC resulted in a decrease in ADG (linear and quadratic, P < 0.01) and a linear decrease in ADFI and G:F (P < 0.05). Experiment 3 was conducted for 28 d to determine the effect of graded levels of DBC. In Exp. 3, DBC were added to the diets at 2% increments from 0 to 8%. All diets contained 1.00% total dietary Lys. In Exp. 3, increasing dietary DBC resulted in a decrease in ADG and ADFI (linear, P < 0.01). Feed efficiency was not significantly affected by the increasing levels of DBC. The results of these 3 experiments indicate that ADG can be maintained with up to 4% DBC, but DBC fed above 2% may have a negative effect on feed efficiency of weanling and grower pigs. The maximum inclusion level of DBC that can be added in a diet for weanling and growing pigs without reducing growth performance is dependent on the Ile:Lys.

Three experiments were conducted to compare dried whey permeate (DWP; 80% lactose) and a carbohydrate product (CHO; 40% lactose, 30% sucrose, and 10% glucose) for nursery pigs. Pigs were fed in a 3-phase feeding program, and diets contained 1.6, 1.4, and 1.2% total Lys for phases 1 (d 0 to 7), 2 (d 7 to 21), and 3 (21 to 28). Dietary treatments included 1) control (no lactose), 2) low level of DWP, 3) high level of DWP, 4) low level of CHO, and 5) high level of CHO. In Exp. 1 (4 reps of 4 pigs per pen; initial BW = 7 kg and 23 d of age), the low and high levels used for each source in each phase were phase 1 (12.5 and 25%), phase 2 (10 and 20%), and phase 3 (6 and 12%). In Exp. 2 (6 reps of 5 pigs per pen; initial BW = 8 kg and 26 d of age) and 3 (4 reps of 4 pigs per pen; initial BW = 6 kg and 21 d of age), the inclusion levels were phase 1 (6 and 12%), phase 2 (3 and 6%), and phase 3 (common diet with no lactose). In Exp. 1, pigs fed diets with DWP or CHO had increased ADG (P = 0.02 and P = 0.01) and ADFI (P = 0.01) compared with pigs fed the control diet during phase 1. Gain:feed was reduced (P = 0.08) for pigs fed diets with CHO. During phases 2, 3, and overall, ADG, ADFI, and G:F were not affected (P > 0.10) by diet. In Exp. 2, pigs fed diets with CHO had increased ADG (P = 0.08 and P = 0.07) and ADFI (P = 0.04 and P = 0.01) compared with pigs fed the control diet during phases 1 and 2. Pigs fed diets with CHO had increased ADFI (P = 0.08 and P = 0.07) in phases 1 and 2 and increased ADG (P = 0.02) in phase 2 compared with pigs fed diets with DWP. Overall, pigs fed diets with DWP and CHO had increased ADFI (P = 0.06 and P = 0.01) compared with pigs fed the control diet, but ADG was increased (P = 0.07) for pigs fed diets with CHO. In Exp. 3, ADG, ADFI, and G:F were not affected (P > 0.10) by DWP or CHO during phase 1. Daily BW gain was increased (P = 0.02 and P = 0.07) for pigs fed diets with DWP or CHO during phase 2 compared with pigs fed the control diet. Overall, ADG was increased (P = 0.05) for pigs fed diets with DWP, but ADFI and G:F were not affected. Results from the combined data of Exp. 2 and 3, indicated that overall ADG (P = 0.05 and P = 0.04) and ADFI (P = 0.04) were increased in pigs fed diets with DWP or CHO compared with pigs fed the control diet. These data suggest that DWP or CHO improve growth performance of weanling pigs.

Three experiments were conducted to evaluate the effect of dried brewers yeast (DBY) as a protein source in prewean (creep) and nursery diets on growth performance of nursing and weanling pigs. In Exp. 1, sows and gilts were provided ad libitum access to the same lactation diet. Litters at 5 d of age were assigned to 1) no prewean feed, 2) a control diet, or 3) the control diet with 4% DBY by replacing soybean meal, available until an average weaning age of 21 d. At weaning, pigs within litters were assigned to 1) a control or 2) the control + 4% DBY, resulting in 6 treatments (3 x 2 factorial arrangement) for the nursery period. During the prewean period, there were no differences (P > 0.10) in average pig weaning weight or ADG between pigs fed the no prewean diet, the control diet, or the DBY diet. In the nursery period, pigs fed DBY had increased (P = 0.05) ADG and G:F during phase 1 and increased (P 0.10) were observed in ADG, ADFI, or G:F. In Exp. 3, pigs were assigned to 1) the control + 5% spray-dried animal plasma or 2) the control + 5% DBY without spray-dried animal plasma. No differences (P > 0.10) were observed in ADG, ADFI, or G:F. Based on our results, DBY can be used in prewean and phase 1 nursery diets with no negative effects on growth performance of nursing and weanling pigs.

Five experiments were conducted to investigate the ability of different phytase products to improve P digestibility in finishing pigs. A corn-soybean meal basal diet containing 0.50% Ca, 0.32% P, and 0.40% Cr(2)O(3) was used to calculate apparent P and GE digestibility. Pigs were individually penned and fed their respective diet for ad libitum intake for 12 d before fecal sampling on d 13 and 14 and blood collection on d 14 for plasma P determination. Experiments 1 through 4 used gilts with across-trial average initial and final BW of 84 and 97 kg, respectively. Pigs were fed Natuphos (Exp. 1), OptiPhos (Exp. 2), Phyzyme (Exp. 3), or RonozymeP (Exp. 4) at 0, 200, 400, 600, 800, or 1,000 phytase units (FTU)/kg (where 1 FTU is defined as the quantity of enzyme required to liberate 1 micromol of inorganic P per min, at pH 5.5, from an excess of 15 micromol/L of sodium phytate at 37 degrees C). Experiment 5 used barrows with initial and final BW of 98 and 111 kg, respectively, and were fed diets containing 0, 500, or 1,000 FTU/kg of Natuphos, OptiPhos, Phyzyme, or RonozymeP. Pigs fed Natuphos (Exp. 1) and OptiPhos (Exp. 2) exhibited a linear and quadratic (P < 0.01) improvement in P digestibility with increasing levels of dietary phytase, whereas pigs fed Phyzyme (Exp. 3) and RonozymeP (Exp. 4) exhibited a linear (P < 0.01) improvement in apparent P digestibility with increasing levels of dietary phytase. In Exp. 5, the improvement in apparent P digestibility with increasing levels of dietary phytase was linear (P < 0.01) for Natuphos, Phyzyme, and RonozymeP, but was linear and quadratic (P < 0.01) for OptiPhos. Based on regression analysis, inorganic P release at 500 FTU/kg was predicted to be 0.070, 0.099, 0.038, and 0.030% for Natuphos, OptiPhos, Phyzyme, and RonozymeP, respectively. These estimates are comparable with those of pigs in Exp. 5, for which the estimated inorganic P release at 500 FTU/kg was 0.102, 0.039, and 0.028% for OptiPhos, Phyzyme, and RonozymeP, respectively, but not for the 0.034% value determined for Natuphos. The effect of dietary phytase on GE digestibility was inconsistent with a linear (P < 0.01) improvement in GE digestibility noted for OptiPhos (Exp. 2 and 5) and RonozymeP (Exp. 4), but the quadratic (P < 0.01) improvement for Natuphos. There was no effect of dietary phytase on plasma inorganic P. The data presented show clear improvements in P digestibility, with the estimated level of inorganic P release being dependent on phytase source and level.

The purpose of this research was to investigate the effect of Cr as chromium propionate (CrProp) on growth performance, carcass traits, meat quality, and the fatty acid profile of fat from pigs fed no supplemented dietary fat, choice white grease (CWG), or tallow. An experiment was conducted with 108 crossbred Yorkshire gilts assigned in a randomized complete block design based on BW (average initial and final BW were 29 ± 3 and 109 ± 7 kg, respectively) and allotted within block to a 2 x 3 factorial arrangement of treatments. The treatment arrangement consisted of 2 levels of Cr supplementation (0 and 200 μg/kg in the form of CrProp) and 3 dietary fat sources (no added fat, CWG, or tallow). Each treatment was replicated 6 times with 3 pigs per replicate pen. The experiment was conducted over time with 3 replicates in each of 2 trials. A 4-phase grower-finisher feeding program was used. Dietary treatments were 1) a corn-soybean meal (C-SBM) diet with no added fat; 2) a C-SBM diet with 4% added tallow; 3) a C-SBM diet with 4% added CWG; 4) diet 1 + 200 μg/kg of Cr as CrProp; and 5) diet 2 + 200 μg/kg of Cr; 6) diet 3 + 200 μg/kg of Cr. Addition of Cr did not affect (P > 0.10) growth performance, but did decrease (P = 0.05) 10th-rib backfat and increase (P = 0.03) percentage of muscle. Gain:feed was increased (P = 0.003) and ADFI was decreased (P = 0.03) by fat addition. Fat addition increased HCW (P = 0.05) and dressing percent (P = 0.03). Average backfat, 9th-rib LM cook loss, and 10th-rib LM drip loss and total loss were decreased (P = 0.02 to 0.04) by tallow. Belly bending on both the teatline and scribe side were increased (P = 0.01 to 0.03) by CWG. Iodine values on belly fat samples were decreased (P = 0.02) by Cr supplementation. In addition, iodine values on belly and loin fat samples were increased (P = 0.001) by CWG. Overall, Cr supplementation decreased backfat and the iodine value of belly fat and increased the percentage of muscle.

SUMMARY Low-protein, amino acid-supplemented, all-vegetable diets for broilers may not result in optimal FCR unless they are supplemented with Gly. Three experiments were conducted to determine the Gly + Ser requirement in a low-CP, corn- and soybean meal-based diet with 0.25% l-Lys·HCl, a level which previously had been shown to result in optimal growth performance of broilers as long as it is supplemented with Gly to maintain a minimum of 2.32% total Gly + Ser. Glycine addition to the diet did not affect ADG or ADFI but decreased FCR. When the FCR data from all 3 experiments were combined, the total Gly + Ser minimum requirement was estimated to be 2.10% (P < 0.014) in 0- to 18-d-old broilers. The response to Gly was not a result of added N from Glu.

Three experiments were conducted to determine the effect of incremental levels of red blood cells (RBC; 0 to 4%, Exp. 1; 0 to 2%, Exp. 2 and 3) on growth performance and carcass traits of finishing pigs. Dietary treatments were formulated to meet or exceed the nutrient requirements of barrows and gilts gaining 350 g of lean BW gain per day and were formulated to contain 0.52% apparent ileal digestible (AID) Lys for barrows and 0.59% AID Lys for gilts. In Exp. 1, barrows and gilts (2 replicates of barrows and 2 of gilts; 4 pigs per pen) were fed 0, 1, 2, 3, or 4% RBC. Initial BW (mean +/- SD) was 84.6 +/- 4.9 and 82.42 +/- 4.8 kg, and final BW was 118.7 +/- 6.5 and 120.0 +/- 9.6 kg for barrows and gilts, respectively. Two barrows and 2 gilts per pen were randomly selected and slaughtered for collection of carcass measurements. Experiment 2 was similar to Exp. 1, except 0, 1, or 2% RBC were added. Initial BW was 82.5 +/- 6.4 and 79.2 +/- 7.0 kg, and final BW was 125.5 +/- 6.2 and 119.8 +/- 8.8 kg for barrows and gilts, respectively. Each dietary treatment had 4 replicates per sex with 4 pigs per pen. One barrow and 1 gilt per treatment replicate were randomly selected and slaughtered for collection of carcass traits and viscera weights. Experiment 3 was similar to Exp. 2 except only barrows were used, and the initial and final BW were 86.0 +/- 5.7 and 133.4 +/- 8.4 kg, respectively. Each dietary treatment had 4 replicates with 3 pigs per pen, and all pigs were slaughtered for collection of carcass traits and viscera weights. In Exp. 1, final BW, ADG, and G:F were decreased linearly (P 0.10) on any remaining carcass measurements. In Exp. 2, there was a quadratic effect (P 0.10) on any other response variable. In Exp. 3, with increased RBC addition, average backfat linearly decreased (P 0.10) on any other response variable. Our data indicate that feeding 3 or 4% RBC decreases growth performance of finishing pigs. However, feeding 1 or 2% RBC to finishing pigs had no detrimental effects on growth performance and increased DP in one experiment.

Research was conducted to determine the level of l-Lys that can be included in corn-soybean meal (C-SBM) diets for broilers before an amino acid (AA) beyond Met, Lys, Thr, or Gly becoming limiting and to determine the order of limiting AA in low CP C-SBM diets. All experiments were conducted with Ross 708 broilers (0 to 18 d of age) in brooder batteries. Treatments contained 7 or 8 replicates with 6 birds per replicate. In all experiments, a control C-SBM diet containing no l-Lys.HCl and a similar diet [positive control (PC) + Gly] with supplemental Gly to provide 2.32% total dietary Gly + Ser were fed. All diets were formulated to contain 1.26% total Lys. All diets with added l-Lys.HCl contained supplemental Gly to provide 2.32% total dietary Gly + Ser. In experiment 1, l-Lys.HCl was added to the diets at 0.02% increments from 0.15 to 0.27%. Compared with the PC + Gly diet, there were no negative effects (P0.10) of supplemental Lys on ADG, ADFI, or G:F. In experiment 2, l-Lys.HCl was added to the diets at 0.05% increments from 0.25 to 0.60%. Compared with the PC + Gly diet, ADG and G:F were decreased (P0.03) in broilers fed diets containing greater than 0.30% l-Lys.HCl but not (P0.10) in the 0.25% l-Lys.HCl diet. In experiment 3, l-Lys.HCl was added to the diets at 0.05% increments from 0.20 to 0.30%. Daily gain was decreased (P0.03) in broilers fed 0.30% l-Lys.HCl but not in those fed 0.20 or 0.25% l-Lys.HCl. In experiment 4, the order of limiting AA was determined in a C-SBM diet containing 0.45% L-Lys.HCl. In addition to the PC and PC + Gly diets, diets consisted of a negative control (NC) diet with 0.45% l-Lys.HCl, NC + 0.247% Ile, NC + 0.484% l-Arg.HCl, NC + 0.249% Val, and all possible 2- and l-way combinations of all 3 AA. Compared with the NC diet, addition of Arg and the combination of Arg and the other AA increased ADG and ADFI, indicating that Arg was the limiting AA in this diet. Experiment 5 was conducted in an identical manner to experiment 4 except the diets with the added AA contained the same ratio of corn to soybean meal that is present in a diet with 0.25% l-Lys.HCl. The results of experiment 5 suggest that Arg and Val are equaling limiting in a diet with 0.25% l-Lys.HCl. In summary, 0.25% l-Lys.HCl can be added to C-SBM diets supplemented with Met, Thr, and Gly with no negative effects on growth performance, and Arg and Val are equaling limiting (after Met, Thr, Lys, and Gly) in diets containing 0.25% l-Lys.HCl.

The objective of this research was to determine the influence of dietary Se on various indicators of Se status and relative liver glutathione peroxidase 1 (GPx-1) messenger RNA (mRNA) levels in growing Holstein bull calves. Calves (n = 14, 7/diet) were started 28 d after birth on a Se-adequate (SeA) or Se-deficient diet (SeD) and maintained on the diet until 180 d of age. Blood samples were taken from each calf for determination of erythrocyte GPx-1 and plasma GPx-3 activities and plasma Se concentration on d 28 of age, every 28 d thereafter, and at 180 d of age. To assess liver Se and GPx-1 mRNA, 3 calves were first killed at d 21 of age for baseline (BSL) measurements, and 4 calves from each treatment were killed at trial conclusion. Feed intake and ADG were not affected (P = 0.62) by dietary Se concentrations. However, liver Se concentration was greater (P < 0.05) for BSL calves and SeA calves than SeD calves, but no difference (P = 0.68) was observed between BSL calves and SeA calves. Plasma Se was greater for SeA calves (P < 0.01) than for SeD calves by d 56 of age. The GPx-1 activity was greater in SeA calves (P < 0.01) by d 84 of age, whereas GPx-3 activity was greater in SeA calves, but not until d 180 of age (P < 0.01). There was a 50% decrease in GPx-1 mRNA for the SeD calves (P < 0.05) compared with SeA calves. Thus, relative GPx-1 mRNA transcript level is reflective of Se status in the bovine. Furthermore, 152 d on a semi-purified, SeD diet is adequate to create a Se deficiency in growing Holstein bull calves started on a SeD diet at 28 d of age.

One hundred fifty gilts (initial and final BW 20 and 107 kg, respectively) were used in a 106-d experiment to determine the effects on growth performance and carcass traits of phytase addition to diets deficient in Lys, Ca, and P. The treatments were 1) positive control [NRC adequate in amino acids (AA), ME, Ca, and P]; 2) a diet with 85% of the Lys of diet 1, but adequate in Ca and P (85L+CaP); 3) 85L+CaP with 500 phytase units/kg phytase, expected to supply Lys, ME, Ca, and available P (aP; 85L-CaP+Phy); 4) 85L-CaP+Phy but with no added phytase (85L-CaP-Phy); and 5) 85L-CaP-Phy but adequate in Ca and P (85L+CaP-E-AA). The nutrient matrix values used for the phytase addition were as follows: Ca 144%, aP 144%, ME 15,246 kcal/kg, Lys 12%, Met 5%, Thr 5%, and Trp 2%. The phytase was provided at 0.083% of the diet and therefore was expected to provide the following nutrients: Ca 0.12%, aP 0.12%, ME 12.7 kcal/kg, Lys 0.01%, Met 0.004%, Thr 0.004%, and Trp 0.002%. Treatment diets were fed in a 4-phase feeding program. The standardized ileal digestible Lys levels in the control were 0.91, 0.79, 0.69, and 0.57% for diet changes at 20, 44, 68, and 87 kg, respectively. Each treatment was replicated 5 times with 6 gilts each. Pigs fed diets with reduced Lys concentrations had lower daily gain (P

Seventy-two primiparous and multip- arous sows (36 per dietary treatment) farrowed in 4 groups were used to evaluate the effects of spray-dried plasma protein (SDP) on sow and litter performance during lactation. Dietary lactation treatments consist- ed of a corn-soybean meal control and a corn-soybean meal diet containing 0.5% SDP. Both diets were for- mulated to contain 1.0% total Lys and 3.46 Mcal/kg of ME and were fed from d 107 ± 1.2 of gestation to weaning. Sows were allotted to dietary treatment based on breed, parity, and the date of d 107 of gestation. Litters were standardized within diet, and pigs were weaned at an average age of 19 ± 2.1 d. Sows were fed 3 times daily during lactation. After weaning, sows were fed a common gestation diet and checked twice daily for estrus. Sows were grouped by parity (young sows, ≤3; mature sows, >3) for statistical analysis. The data were analyzed as a 2 × 2 factorial arrangement of treatments; the factors were parity (≤3 or >3) and SDP (0 or 0.5%). Treatment differences were consid- ered significant at P 0.10) were ob- served. The results of this research indicate that SDP increased productivity of sows in parity 4 or greater.

Two experiments (140 pigs in Exp. 1; 120 pigs in Exp. 2) evaluated a marine-based hydrolyzed protein source, (Peptiva Vitech Bio-Chem, San Fernando, CA) as a replacement for spray dried plasma protein (SDPP) in phase I weanling pig diets. Pigs (19 ± 4 d of age) were fed diets with protein supply based mainly on soy protein, or similar diets supplemented with SDPP or Peptiva after weaning for 7 to 10 d. The SDPP and Peptiva were supplemented at 3 and 6%, respectively, in Exp.1 and 1.5 and 3% in Exp. 2. In Exp. 1, pigs fed diets with SDPP had greater (P 0.05). A third experiment using 48 pigs investigated supplementation of SDPP or Peptiva in phase I diets on diet digestibility and N balance. Results indicated that 6% dietary inclusion of either specialty protein had no impact on N retention, digestibility, or protein biological value (P = 0.22 to 0.39) when compared with the control diet. Alteration in diet digestibility is not an important contributing factor to improved growth performance when SDPP is supplemented in phase I pig diets. The hydrolyzed protein source was acceptable as a general protein supplement, but did not elicit phase I growth stimulation typically observed with SDPP.

SUMMARY Chromium has been considered by many nutritionists as an essential nutrient for animals and humans. Research on the use of Cr from organic sources in poultry is limited. Two experiments were conducted to determine the effects of dietary addition of 0, 200, 400, or 800 ppb Cr as chromium propionate on growth performance and carcass traits in 0- to 42- or 0- to 49-d-old broilers. The results of these experiments indicate that Cr as chromium propionate improved feed efficiency in the later phases of growth and decreased mortality in one experiment but not another. Also, chromium propionate supplementation had no effect on carcass traits.

A cooperative regional research study using 194 sows, from which data were collected from 381 litters, was conducted at 3 research stations to determine the effects of added psyllium (a concentrated fiber source) or soybean hulls to gestation diets on reproductive performance of sows and preweaning performance of their pigs. Primiparous and multiparous sows were allotted to the 3 treatments of control (corn and soybean meal-based), 0.30% psyllium, or 20% soybean hulls. Sows fed the control and 0.30% psyllium diets were provided 1.82 kg/d, and sows fed the 20% soybean hulls diet were provided 2.0 kg/d to equalize ME, Lys, Ca, P, and vitamin and trace mineral intake. Treatments 1 to 3 had 130, 130, and 121 litters per treatment from 64, 64, and 63 sows, respectively. Gestating sows fed psyllium had a greater (P 0.10) by diet. Sows fed psyllium had a reduced (P < 0.03) feed intake compared with sows fed soybean hulls for d 5 to 7 postpartum, and sows fed the control diet were intermediate. Fecal scores (1 to 5 with 1 = dry and 5 = watery) were greater (P < 0.001) and DM content was less (P < 0.001 to 0.01) in the feces of sows fed soybean hulls compared with sows fed psyllium or the control diet on d 112 of gestation and d 4 postpartum. Fecal scores were greater (P < 0.10) and fecal DM content was less (P < 0.02) in sows fed psyllium compared with sows fed the control diet only on d 4 postpartum. In summary, sows fed soybean hulls during gestation had reduced BW compared with sows fed the control diets. In contrast, sows fed psyllium had an increased BW.

Two experiments were conducted to determine the effect of 2 carrier sources of vitamin E on growth performance and excreta and liver vitamin E concentrations of broilers. Chicks were pretested from d 0 to 7 posthatching on a corn-soybean meal diet without vitamin E supplementation, and the experiments lasted from d 7 to 19 posthatching. Each treatment in both experiments was replicated with 6 pens with 5 chicks each. Initial and final BW were 155 and 684 g in experiment 1 and 155 and 691 g in experiment 2. In experiment 1, the dietary treatments were the corn-soybean meal diet with varying concentrations (0, 30, 100, or 300 IU/kg) of supplemental vitamin E either absorbed to verxite (VE) or adsorbed to silica (SE). In experiment 2, the dietary treatments were the 0 and 30 IU/kg of vitamin E as VE or SE. In experiment 1, feed intake decreased and gain:feed increased as concentration of VE increased, but feed intake increased and gain:feed decreased as concentration of SE increased (source x concentration, P0.03). Gain, feed intake, and gain:feed were not affected (P0.10) by the vitamin E carrier source in experiment 2. The mean excreta vitamin E concentration at d 7 posthatching was 17.2 IU/kg (DM basis). The percentages of vitamin E excreted were based on analyzed vitamin E concentrations in the diet. At 100 and 300 IU/kg of supplemental vitamin E, an average of 94 and 44% of vitamin E intake from broilers fed vitamin E from VE and SE, respectively, was excreted (vitamin E source, P0.01; source x concentration, P0.08), but at 30 IU/kg of vitamin E, 49 and 45% of vitamin E intake from broilers fed vitamin E from VE and SE was excreted. In experiment 2, 52 and 43% of vitamin E intake from VE and SE was excreted (source, P0.02). Liver alpha-tocopherol concentration was not different (P0.10) between the sources of vitamin E in either experiment. Increased concentrations of vitamin E increased liver alpha-tocopherol concentrations (P0.01). On the basis of the results of excreted vitamin E, vitamin E adsorbed to SE was more available than vitamin E absorbed to VE, but on the basis of liver vitamin E concentration, their availabilities were similar.

Eighty-six primiparous or multiparous sows and their pigs were used to evaluate the effects of changing DCAD in late gestation and in lactation on sow productivity. Sows were allotted to treatment based on parity and their farrowing date. Experiment 1 was a preliminary experiment conducted to determine the level of DCAD that would reduce urinary pH. Twenty sows were used in Exp. 1, and the dietary treatments consisted of a corn-soybean meal diet with 4 levels of DCAD (140, 103, 80, and 56 mEq/kg). These DCAD were achieved by addition of 4 levels of chloride (SoyChlor; 0, 1.5, 2.5, and 3.5% of the diet). The diets were fed from d 107 of gestation to weaning. Urinary pH was linearly decreased (P

Two experiments were conducted with finishing barrows to determine the effect of low CP, amino acid (AA) supplemented diets on growth performance and carcass traits. In Exp. 1, 80 barrows (initial and final BW of 85.5 and 117.5 kg, respectively) were allotted to 4 treatments (5 replicates of 4 pigs per replicate). The dietary treatments were 1) corn-soybean meal diet (C-SBM) with 0.54% true ileal digestible Lys; 2) diet 1 but with crystalline Lys, Thr, and Trp to lower CP (LCP C-SBM); 3) corn-soy protein isolate diet (C-SPI) equal in Lys to diet 1; and 4) diet 3 but with crystalline Lys, Thr, and Trp to lower CP (LCP C-SPI). Daily gain was increased when CP was reduced in pigs fed the SPI diet but decreased in pigs fed the SBM diet (soy source x CP interaction, P

An experiment was conducted to determine the interactive effects of Zn, Cu and Mn addition to diets of 0 to 14-d old broilers on growth performance, bone breaking strength, bone ash percentage and tissue mineral concentrations. Two levels of Zn (0 or 75 ppm, as Zn sulfate), 2 levels of Mn (0 or 100 ppm, as Mn sulfate) and 2 levels of Cu (0 or 7 ppm, as Cu sulfate) were supplemented to corn-soybean meal diets in a 2×2×2 factorial arrangement. Each treatment had 6 replications with 5 chicks each and the initial and final BW were 46 and 382 g. Daily gain, daily feed intake, gain:feed, bone breaking strength and bone and pancreatic Zn concentrations were increased (p

An experiment was conducted to compare the effects of organic (Zn AA complex, ZnAA) and inorganic Zn (ZnSO4) sources on sows and their progeny during gestation and lactation and on the pigs during the nursery period. The dietary treatments were 1) a corn-soybean meal diet with 100 ppm Zn from ZnSO4 (control); 2) diet 1 + 100 ppm additional Zn from ZnSO4; and 3) diet 1 + 100 ppm additional Zn from ZnAA. Dietary additions were on an as-fed basis. Thirty-one primaparous and multiparous sows were allotted to the treatment diet beginning on d 15 of gestation and continuing through lactation. At weaning (d 17 of age), 202 pigs (63, 55, and 84 pigs for treatments 1 to 3, respectively) were allotted to the same dietary treatment as their dam. The pigs were fed a 3-phase diet regimen during the nursery period: d 0 to 7 (phase I); d 7 to 21 (phase II); and d 21 to 28 (phase III). At weaning and at the end of phase III, 1 gilt per replicate was killed, and the left front foot, liver, pancreas, and entire small intestine were removed. Diet had no effect (P > 0.10) on any response during gestation. During lactation, there was an increase (P 0.10) by diet. Pigs fed ZnSO4 had greater duodenal villus width (P < 0.05) than those fed ZnAA, and pigs fed ZnSO4 or the control diet had greater ileal villus width (P < 0.05) than those fed ZnAA. Pigs fed ZnSO4 or ZnAA had more (P < 0.05) bone Zn than those fed the control diet. Liver Zn concentration was greatest in pigs fed ZnSO4, followed by those fed ZnAA, and then by those fed the control diet (P < 0.05). Pancreas Zn was increased (P < 0.05) in pigs fed ZnSO4 compared with those fed the control diet. These results suggest that 100 ppm Zn in trace mineral premixes provides adequate Zn for optimal growth performance of nursery pigs, but that 100 ppm additional Zn from ZnAA in sow diets may increase pigs born and weaned per litter.

Four experiments were conducted to determine the effects of supplemental Trp on meat quality, plasma and salivary cortisol, and plasma lactate. Experiment 1 was a preliminary study to measure plasma cortisol concentrations in 4 barrows (50 kg of BW) that were snared for 30 s at time 0 min. Pigs were bled at -60, -30, -15, 2, 4, 6, 8, 10, 15, 20, 25, 30, 45, 60, 90, and 120 min. Plasma cortisol was near maximum 10 min after the pigs were snared. In Exp. 2, 20 barrows (50 kg of BW) were allotted to a basal corn-soybean meal diet or the basal diet with 0.5% supplemental l-Trp for 5 d. After the 5-d feeding period, pigs were snared for 30 s and bled at -10, 0, 2, 4, 6, 8, 10, 15, 20, 25, 30, 45, 60, 90, and 120 min after snaring. Pigs fed the diet with supplemental Trp had a lower (P < 0.01) mean plasma cortisol than pigs fed the basal diet. Plasma lactate also was decreased (P < 0.07) by supplemental Trp. In Exp. 3, the same pigs and treatments were used as in Exp. 2, but 5 pigs were snared and 15 pigs adjacent to those being snared were bled to determine if pigs are stressed when they are adjacent to pigs being snared. For pigs adjacent to snared pigs, the area under the curve (P < 0.06) and mean for plasma cortisol was lower (P < 0.01) in pigs fed Trp relative to those fed the basal diet. In Exp. 4, 90 barrows (initial BW of 106 kg) were allotted to 6 treatments in a 3 x 2 factorial arrangement. Three diets with Trp (basal diet, basal supplemented with 0.5% Trp for 5 d, or pigs fed the basal diet with a 0.1 g/kg of BW Trp bolus given 2 h before slaughter) were combined with 2 handling methods (minimal and normal handling). Dressing percent, 24-h pH, and 24-h temperature were reduced in the minimally handled pigs (P < 0.10) compared with the normally handled pigs. Pigs fed Trp in the diet relative to those fed the basal diet had increased 45-min temperature, Commission Internationale de l'Eclairage (CIE) redness (a*) and yellowness (b*) values, and drip and total losses (P < 0.10). Tryptophan in bolus form decreased 45-min pH in the minimally handled pigs but increased 45-min pH in the normally handled pigs (handling x Trp bolus interaction, P = 0.08). Tryptophan in the diet increased CIE lightness (L*) in minimally handled pigs but decreased CIE L* in the normally handled pigs (handling x Trp diet interaction, P = 06). No other response variables were affected by handling method or Trp. Results indicate that Trp decreases plasma cortisol but has no positive effect on meat quality.

We evaluated and compared various broken-line regression models and SAS (SAS Inst. Inc., Cary, NC) procedures for estimating nutrient requirements from nutrient dose response data. We used the SAS (Version 9) procedures NLIN and NLMixed and the response data of Parr et al. (2003), who evaluated the isoleucine requirement of growing swine. The SAS NLIN was used to fit 2 different broken-line regression models: a simple 2 straight-line, one-breakpoint model and a quadratic broken-line model in which the response below the single breakpoint was quadratic; there was a plateau above the breakpoint. The latter was fit using 2 different approaches in NLIN. We also used SAS NLMixed to fit 3 different broken-line models: the 2 straight-line, one-breakpoint model that included a random component for the plateau; the quadratic broken-line model that included a random component for the plateau; and the quadratic broken-line model that included random components for both the plateau and the slope of the curve below the requirement. The best fit (greater adjusted R2; least log likelihood) was achieved using SAS NLMixed and the quadratic model with a random component for asymptote included in the model. Model descriptions, SAS code, and output are presented and discussed. Additionally, we provide other examples of possible models and discuss approaches to handling difficult-to-fit data.

Stress occurs in intensive pig farming when piglets are weaned and mixed. In this study, we investigated whether this stress might be reduced with elevated dietary levels of Trp. The effects of supplemental dietary Trp (5 g/kg of feed, as-fed basis) were tested on the neuroendocrine system, intestinal integrity, behavior, and growth performance in nursery pigs, both before and after mixing. Mixing occurred 5 d after weaning and diet introduction. On d 4, 5, and 6, Trp-fed pigs vs. control pigs showed approximately a 2-fold elevation in plasma Trp concentrations (68 +/- 7 vs. 32 +/- 2 micromol/L; P 0.10). In conclusion, supplemental dietary Trp (5 g/kg) to piglets increased hypothalamic serotonergic activity, reduced the salivary cortisol response to mixing, improved intestinal morphology, and reduced physical activity 10 d after diet introduction. Consequently, diets containing high Trp levels improved neuroendocrine components of stress and increased gastrointestinal robustness but did not affect behavioral reactivity in nursery pigs during weaning and mixing.

Microbial phytase has been shown to increase the availability of Ca, P, ME, amino acids, and trace minerals in diets of broilers. By increasing the availability of trace minerals, phytase may be able to replace the trace mineral premix in diets for broilers. Therefore, a 43-d floor pen study that included diets with and without phytase and with and without supplemental trace minerals was conducted to evaluate this possibility. The Ca and nonphytate P concentrations were decreased by 0.10% in diets with phytase. Growth performance was not affected in chicks fed diets with or without the trace minerals, but adding phytase had positive effects on growth performance. Removal of the trace minerals had a negative effect on bone strength. Removal of the trace minerals, addition of phytase, or both had variable effects on tissue trace mineral concentrations.

Four experiments (EXP) were conducted to evaluate the effects of virginiamycin (Vm) in diets adequate or reduced in Ca or nonphytate P (nPP) levels on growth performance and bone response variables in chicks. All diets were corn-soybean meal (C-SBM) based, and all treatments were replicated 6 or 8 times with 5 or 6 chicks each. In EXP 1 and 2, the dietary treatments were 1) C-SBM with 1.00% Ca and 0.45% nPP (positive control; PC); 2) C-SBM with 0.80% Ca and 0.45% nPP (0.80Ca); 3) C-SBM with 1.00% Ca and 0.35% nPP (0.35nPP); and 4 to 6) Diets 1 to 3 with 11 (EXP 1) or 22 (EXP 2) ppm of Vm. In EXP 1, daily gain (ADG), feed intake (ADFI), bone breaking strength (BBS), milligrams of ash per gram of Ca intake (ASH/Ca), and BBS per gram of Ca (BBS/Ca) or nPP (BBS/nPP) intake were increased in chicks fed Vm (P < 0.04 to 0.07). Chicks fed the 0.35nPP diet with Vm had increased ADG, ADFI, BBS, milligrams of tibia ash (ASH), BBS/Ca, and BBS/nPP (nPP x Vm, P < 0.03 to 0.10). Chicks fed the 0.80Ca diet with Vm had increased ASH, milligrams of ASH per gram of nPP intake (ASH/ nPP), and ASH/Ca (P < 0.01 to 0.09). Tibia ash, BBS, gain:feed (G:F), BBS/nPP, and ASH/nPP were decreased in chicks fed the 0.80Ca diet (P < 0.01 to 0.07). Bone ash percentage (BAP), BBS, BBS/Ca, ASH, and ASH/Ca were decreased in chicks fed the 0.35nPP diets (P < 0.01); ASH/ nPP was increased (P < 0.01). In EXP 2, BAP, ASH, ASH/ Ca, and ASH/nPP were increased in chicks fed Vm (P < 0.02 to 0.07). Chicks fed the 0.80Ca diet had a decreased ASH/nPP (P < 0.04) but an increased BBS/Ca and ASH/ Ca (P < 0.01 to 0.02). Chicks fed the 0.35nPP diet had decreased ADG, ADFI, G:F, BBS, BAP, ASH, ASH/Ca, and BBS/Ca (P < 0.01 to 0.04), but BBS/nPP and ASH/ nPP were increased (P < 0.01 to 0.04). In EXP 3, the dietary treatments were 1) PC; 2) C-SBM with 0.70% Ca and 0.45% nPP (0.70Ca); 3) C-SBM with 1.00% Ca and 0.25% nPP (0.25nPP); 4 to 6) Diets 1 to 3 with 9 ppm of Vm. The addition of Vm to the 0.25nPP diet decreased BBS (nPP x Vm, P < 0.06), but Vm increased BBS in the 0.70Ca and PC diets (P < 0.02). Chicks fed the 0.25nPP diet had decreased ADG, ADFI, and BBS (P < 0.01), and chicks fed the 0.70Ca diets had reduced ADFI, BBS, and G:F (P < 0.03 to 0.10). In EXP 4, 4 levels of nPP (0.15, 0.25, 0.35, or 0.45%) and 3 levels of Vm supplementation (0, 11, or 22 ppm) in a 4 x 3 factorial arrangement were used. The addition of Vm increased ADG, BBS, ASH, ASH/Ca, and ASH/nPP only in chicks fed diets with 0.35 or 0.45% nPP (nPP x Vm, P < 0.05). Daily gain, ADFI, G:F, BBS, BAP, BBS/Ca, and ASH were increased as nPP levels were increased (P < 0.01), but BBS/nPP and ASH/nPP were decreased (P < 0.01) as nPP levels were increased. The results obtained from these EXP indicate that Vm, regardless of supplementation level, can partially overcome an nPP deficiency when nPP levels are = 0.35%.

Six experiments were conducted to validate an Ile-deficient diet and determine the Ile requirement of 80- to 120-kg barrows. Experiment 1 had five replications, and Exp. 2 through 6 had four replications per treatment; all pen replicates had four crossbred barrows each (initial BW were 93, 83, 85, 81, 81, and 88 kg, respectively). All dietary additions were on an as-fed basis. In Exp. 1, pigs were fed a corn-soybean meal diet (C-SBM) or a corn-5% blood cell (BC) diet with or without 0.26% supplemental Ile (C-BC or C-BC+Ile) in a 28-d growth assay. On d 14, pigs receiving the C-BC diet were taken off experiment as a result of a severe decrease in ADFI. Growth performance did not differ for pigs fed C-SBM or C-BC + Ile (P = 0.36) over the 28-d experiment. In Exp. 2, pigs were fed the C-BC diet containing 0.24, 0.26, 0.28, 0.30, or 0.32% true ileal digestible (TD) Ile for 7 d in an attempt to estimate the Ile requirement using plasma urea N (PUN) as the response variable. Because of incremental increases in ADFI as TD Ile increased, PUN could not be used to estimate the Ile requirement. In Exp. 3, pigs were fed the C-BC diet containing 0.28, 0.30, 0.32, 0.34, or 0.36% TD Ile. Daily gain, ADFI, and G:F increased linearly (P < 0.01) as Ile increased in the diet. Even though there were no effects of TD Ile concentration on 10th rib fat depth or LM area, kilograms of lean increased linearly (P < 0.01) as TD Ile level increased. In Exp. 4, pigs were fed a C-SBM diet containing 0.26, 0.31, or 0.36% TD Ile. There were no differences in ADFI or ADG; however, G:F increased linearly (P = 0.02), with the response primarily attributable to the 0.31% Ile diet. In Exp. 5, pigs were fed 0.24, 0.27, 0.30, 0.33, or 0.36% TD Ile in a C-SBM diet. There were no differences in growth performance; however, average backfat, total fat, and percentage of fat increased quadratically (P < 0.10) with the addition of Ile. In Exp. 6, pigs were fed a 0.26% TD Ile C-SBM diet with or without crystalline Leu and Val to simulate the branched-chain AA balance of a C-BC diet. There were no differences in ADFI or ADG, but G:F increased (P = 0.09) when Leu and Val were added. In summary, the Ile deficiency of a C-BC diet can be corrected by the addition of Ile, and because ADFI was affected by Ile addition, the PUN method was not suitable for assessing the Ile requirement. The TD Ile requirement for 80- to 120-kg barrows for maximizing growth performance and kilograms of lean is not < 0.34% in a C-BC diet, but may be as low as 0.24% in a C-SBM diet.

Four completely randomized designed experiments (EXP) were conducted to determine the effect of energy, amino acid (AA) levels, and bulk density of diets on growth performance of chicks fed diets containing corn (C) or cornstarch:dextrose (CD) as energy sources and soybean meal (SBM) or soy protein isolate (SPI) as protein sources. The chicks were fed C-SBM diets 6 to 8 d posthatching before allotment to treatment, and the assay periods ranged from 7 to 14 d. Initial weights were 86, 93, 94, and 71 g in EXP 1 to 4, respectively. Treatments were replicated 6 to 8 times with 4, 5, or 6 chicks per replicate. In EXP 1, the treatments were 1) C-SBM (1.26% Lys and 3,200 kcal of ME/kg); 2) CD-SPI (1.26% Lys and 3,460 kcal of ME/kg); 3) CD-SPI (1.36% Lys and 3,460 kcal of ME/kg); and 4) CD-SPI (1.26% Lys and 3,200 kcal of ME/kg). The AA in all diets were increased in proportion to Lys. In EXP 2, chicks were fed C or CD as the energy source and SBM or SPI as the protein source in a 2 x 2 factorial arrangement. In EXP 3, the treatments were 1) C-SBM (1.26% Lys and 3,200 kcal of ME/kg); 2) CD-SPI (1.26% Lys and 3,200 kcal of ME/kg); 3) Diet 1 limit-fed to chicks consuming 90% of Diet 2; 4) Diet 2 limit-fed to chicks consuming 90% of Diet 2. In EXP 4, Diets 1 and 2 were the same as Diets 1 and 2 in EXP 3, but fed in mash or pelleted form. In all EXP, chicks with access ad libitum to diets with SPI had decreased (P0.02) average daily gain (ADG) and feed intake (ADFI) compared with those with access ad libitum to diets with SBM. In EXP 2, feeding C- or CD-dextrose as the energy source had no effect (P0.05) on ADG, ADFI, or gain:feed. In EXP 3, ADG was decreased in chicks fed the diets with SPI relative to those fed diets with SBM, but the decrease was much greater in chicks that had access ad libitum to feed (protein source x feed intake, P0.01) than in those limit-fed to the same feed intake. In EXP 4, ADG, ADFI, and gain:feed were decreased (P0.01) in chicks fed diets with SPI as the protein source. Pelleting increased (P0.01) ADG, ADFI, and gain:feed regardless of protein source, but the increase was much greater in chicks fed the diets with SPI (protein source x feed form, P0.01). Results from these EXP indicate that diets with SPI compared with SBM do not result in maximum growth performance in commercial broilers, and the problem may be due somewhat to nutrient deficiency but more to the physical form of the diet.

An experiment was conducted to determine the interactive effects of Eimeria acervulina infection and phytase in male broiler chicks. Chicks were standardized from 0 to 4 d posthatching, and the assay period was 5 to 15 d. Treatments were replicated with 6 pens of 5 chicks each. The initial and final BW were 67 and 363 g. A corn-soybean meal diet formulated to provide 1.26% total Lys and 3,200 kcal of ME/kg was used, and it was adequate in all other nutrients except Ca and nonphytate P (NPP) when appropriate. The treatments were in a 2 x 2 x 2 factorial arrangement: adequate Ca and NPP (1.0% Ca and 0.45% NPP) or inadequate Ca and NPP (0.80% Ca and 0.25% NPP), 0 or 600 phytase units/kg of diet, and uninfected or infected with 400,000 E. acervulina oocysts on d 0, 3, and 6 of the experiment. Daily gain, average daily feed intake, and gain:feed (GF) were reduced (P < 0.01) by the coccidial infection and the reduction in Ca and NPP. Phytase addition increased (P < 0.02) average daily gain and average daily feed intake, regardless of the Ca and NPP contents of the diet or the presence of coccidiosis. The GF was increased by phytase but only in uninfected chicks (phytase x coccidiosis, P < 0.02). Toe and tibia ash percentages were decreased (P < 0.01) in chicks fed diets deficient in Ca and NPP, but tibia ash was decreased more by Ca and NPP in healthy chicks than in infected chicks (coccidiosis x Ca and NPP, P < 0.02). Phytase increased (P < 0.02) toe and tibia ash but only in diets deficient in Ca and NPP (phytase x Ca and NPP, P < 0.01). Phytase increased toe ash percentage of healthy chicks fed diets deficient in Ca and NPP, but it had less of an effect in infected chicks fed diets deficient in Ca and NPP (coccidiosis x Ca and NPP x phytase, P < 0.08). Also, phytase was less effective in increasing tibia ash percentage in coccidiosis-infected chicks than in uninfected chicks (phytase x coccidiosis, P < 0.02). These data indicate that phytase is effective in the presence of a coccidial infection, but based on GF and tibia ash percentage, it may not be as effective as in uninfected chicks. Also, phytase increased average daily gain and average daily feed intake in uninfected chicks fed diets formulated to be adequate (or in excess) in all nutrients for male broiler chicks.

Five experiments were conducted to determine the true ileal digestible Trp (tidTrp) requirement of growing and finishing pigs fed diets (as-fed basis) containing 0.87% (Exp. 3), 0.70% (Exp. 4), 0.61% (Exp. 5), and 0.52% (Exp. 1 and 2) tidLys during the early-grower, late-grower, early-finisher, and late-finisher periods, respectively. Treatments were replicated with three or four replications, with three or four pigs per replicate pen. Treatment differences were considered significant at P = 0.10. Experiment 1 was conducted with 27 pigs (initial and final BW of 78.3 +/- 0.5 and 109.8 +/- 1.9 kg) to validate whether a corn-feather meal (FM) tidTrp-deficient (0.07%) diet, when supplemented with 0.07% crystalline l-Trp, would result in growth performance and carcass traits similar to a conventional corn-soybean meal (C-SBM) diet. Pigs fed the corn-FM diet without Trp supplementation had decreased growth performance and carcass traits, and increased plasma urea N (PUN) concentration. Supplementing the corn-FM diet with Trp resulted in greater ADG and G:F than pigs fed the positive control C-SBM diet. Pigs fed the corn-FM diet had similar carcass traits as pigs fed the C-SBM diet, but loin muscle area was decreased and fat thickness was increased. In Exp. 2, 60 pigs (initial and final BW of 74.6 +/- 0.50 and 104.5 +/- 1.64 kg) were used to estimate the tidTrp requirement of finishing pigs. The levels of tidTrp used in Exp. 2 were 0.06, 0.08, 0.10, 0.12, or 0.14% (as-fed basis). Response variables were growth performance, PUN concentrations, and carcass traits and quality. For Exp. 2, the average of the estimates calculated by broken-line regression was 0.104% tidTrp. In Exp. 3, 4, and 5, barrows (n = 60, 60, or 80, respectively) were allotted to five dietary treatments supplemented with crystalline l-Trp at increments of 0.02%. The basal diets contained 0.13, 0.09, and 0.07% tidTrp (as-fed basis) in Exp. 3, 4, and 5, and initial BW of the pigs in these experiments were 30.9 +/- 0.7, 51.3 +/- 1.1, and 69.4 +/- 3.0 kg, respectively. The response variable was PUN, and the basal diet used in Exp. 3 and 4 contained corn, SBM, and Canadian field peas. The tidTrp requirements were estimated to be 0.167% for pigs weighing 30.9 kg, 0.134% for pigs weighing 51.3 kg, and 0.096% for pigs weighing 69.4 kg. Based on our data and a summary of the cited literature, we suggest the following total Trp and tidTrp requirement estimates (as-fed basis): 30-kg pigs, 0.21 and 0.18%; 50-kg pigs, 0.17 and 0.14%; 70-kg pigs, 0.13 and 0.11%; and in 90-kg pigs, 0.13 and 0.11%.

An experiment was conducted to determine the effect of dietary Cr propionate (CrProp) on growth, carcass traits, and pork quality of crossbred finishing gilts. Dietary treatments were 0 or 200 ppb Cr (as CrProp; as-fed basis), and each treatment was replicated four times with five gilts per replicate pen. Gilts were fed diets containing 0.82% lysine from 73 to 80 kg BW and 0.64% lysine from 80 to 115 kg BW. At the end of the trial, carcass and pork quality data were collected from four gilts per replicate. Average daily gain, ADFI, and G:F were not affected (P = 0.76 to 0.96) by CrProp. Before delivery at the abattoir, shrink loss was determined after an 18-h fast (fasting shrink) and after hauling (shipping shrink) pigs for 2.66 h (209.2 km). Fasting, shipping, and overall shrink were not affected (P = 0.14 to 0.39) by CrProp. Carcass length was increased (P = 0.03) in pigs fed CrProp. Loin muscle area, 10th-rib backfat thickness, average backfat thickness, dressing percent, muscle score, fat-free lean, and percent lean were not affected (P = 0.18 to 0.95) by CrProp. Twenty-four-hour loin pH was increased (P = 0.10) in pigs fed CrProp, but 45-min loin and ham pH and 24-h ham pH were not affected (P = 0.39 to 0.83) by CrProp. Subjective (color, marbling, firmness, and wetness) and objective (Commission Internationale de l'Eclairage L*, a*, b*) assessments of the loin muscle (at the 10th-rib interface) were not affected (P = 0.62 to 0.99) by CrProp. Forty-eight-hour drip (P = 0.10) and 21-d purge loss (P = 0.01) were decreased in pigs fed CrProp, but cook and total loss (drip + cook loss) and shear force were not affected (P = 0.35 to 0.53) by CrProp. Plasma cortisol, glucose, and lactate concentrations were not affected (P = 0.28 to 0.97) by CrProp after transportation or during exsanguination. These data indicate that CrProp may improve some aspects of pork quality (loin pH, drip and purge loss) but not growth performance or carcass traits.

A study was conducted to evaluate the mineral content of pork tissue with particular emphasis on Se between various states (regions) having different diet (grain) indigenous Se concentrations. The study involved 19 states in the north, central, and southern regions of the United States, with committee members of NCR-42 and S-1012 (formerly S-288). A total of 62 pigs were used, with collaborators sending 100-g samples each of loin, heart, and liver, and a 3- to 4-g sample of hair (collected along the topline) from two to five market-weight pigs to a common laboratory for analysis. Diets at each station were formulated with locally purchased soybean meal and grain that was either grown or normally fed to pigs within their state. Tissues were analyzed for Se, but only the loin was analyzed for the macro- and micromineral elements. Correlation of dietary minerals to the tissue element was determined. The results demonstrated differences in tissue Se among states (P 0.90; P < 0.01). States in the west-central region of the United States and west of the Mississippi river had higher dietary Se and tissue Se concentrations than states in the eastern section of the Corn Belt, east of the Mississippi river, and along the East Coast. Generally, states did not differ greatly in their loin macro- and micromineral concentrations. The simple correlation of dietary minerals to their corresponding loin mineral concentration was generally non-significant, but most macrominerals had decreasing mineral concentrations when the dietary mineral level was higher. These results indicate that regional differences in tissue Se were influenced more by the indigenous Se content of the diet (grain) fed to the pigs than from sodium selenite.

A 28-d experiment using 288 Hy-Line W-36 laying hens was conducted to compare sodium selenite (SS) with Se-enriched yeast (SY). The Se from SS or SY was supplemented into a corn-soybean meal basal diet at 0, 0.15, 0.30, 0.60, or 3.00 ppm, and the basal diet was formulated to provide 0.82% lysine and 2,950 kcal/kg of ME. Each treatment was replicated 4 times with 2 cages of 4 hens per cage in each replicate. Hen production was assessed daily, and 2 eggs per replicate were collected every 4 d for whole-egg Se analysis. Albumen quality was assessed at 2 egg storage temperatures (7.2 vs. 22.2 degrees C) with the eggs collected on d 24 and 28, respectively. The percentage of dirty and cracked eggs was greater (P0.04) in hens fed SY than in those fed SS. Percentage hen-day production was not affected (P0.05) by diet. Albumen quality of eggs stored at 22.2 degrees C was improved (P0.04) in eggs from hens fed SS, but there was no difference (P0.05) in albumen quality of eggs stored at 7.2 degrees C. Egg weight was linearly increased (P0.01) by SY. Whole-egg Se levels were linearly increased (P0.01) as dietary Se level increased for both sources of Se, but eggs from hens fed SY had higher (P0.01) Se concentrations than those fed SS. The results from this experiment indicate that percentage hen-day production is not affected by Se source, and that SY increases egg Se concentrations more than SS.

Research with corn-soybean meal diets was conducted to compare phytase sources in commercial broilers. A Ca to nonphytate P (nPP) ratio of 2.5:1 was maintained in all diets. Experiments 1 and 2 were conducted from d 4 to 13 (experiment 1) or d 9 to 23 post-hatching (experiment 2) in batteries. The 10 treatments used in both experiment were: Diets 1 to 4 = 0.20, 0.25, 0.30, or 0.35% nPP; Diets 5 to 7 = diet 1 plus 100, 200, or 300 phytase units/kg of diet from Natuphos (NAT); and Diets 8 to 10 = diet 1 plus 100, 200, or 300 phytase units/ kg of diet from Ronozyme (RON). As nPP levels increased, daily gain (ADG), feed intake (ADFI), gain:feed, and toe and tibia ash percentage were linearly increased (P0.06) in experiments 1 and 2. Incremental addition of phytase, regardless of source, linearly increased (P0.07) ADG and ADFI in experiment 1. Broilers fed NAT had higher (P0.07) toe ash percentage in experiment 1 and 2, and higher (P0.02) ADG and ADFI in experiment 2 than those fed RON. In experiment 3, 3,360 broilers were used to test 2 dry phytase products from 0 to 41 d posthatching in a 3-phase feeding program. The treatments were: Diet 1) adequate Ca and nPP; Diet 2) nPP reduced by 0.20%; Diets 3 to 5 = diet 2 plus 300, 500, or 750 phytase units/kg of diet from NAT; and Diets 6 to 8 = Diet 2 plus 300, 500, or 750 phytase units/kg of diet from RON. Broilers fed the adequate Ca and nPP diet had improved ADG and ADFI overall, and tibia ash weight and percentage in all growth phases (P0.03) compared with those fed the reduced Ca and nPP diets. Overall, ADG and ADFI were linearly increased (P0.05) by incremental phytase addition in experiment 3. Both NAT and RON produce similar growth and bone ash traits in commercial broilers.

Two experiments were conducted to determine the interactive effects of phytase with and without a trace mineral premix (TMP) in diets for nursery, growing, and finishing pigs on growth performance, bone responses, and tissue mineral concentrations. Pigs (initial and final BW of 5.5 and 111.6 kg [Exp. 1] or 5.4 and 22.6 kg [Exp. 2]) were allotted to treatments on the basis of BW with eight (Exp. 1) or six (Exp. 2) replications of six or seven pigs per replicate pen. Pigs were started on the diets the day of weaning (average of 18 d). In both experiments, the treatments were with or without 500 phytase units/kg of diet and with or without the TMP in a 2 x 2 factorial arrangement. The Ca and available P concentrations were decreased by 0.10% in diets with phytase. The nursery phase consisted of Phase I (7 d), Phase II (14 d), and Phase III (13 d) periods. In Exp. 1, 26 of 52 pigs fed the diet without the TMP and without phytase had severe skin lesions and decreased growth performance; therefore, pigs fed this diet were switched to the positive control diet. In Exp. 2, the treatment without the TMP and without phytase had 12 replications instead of six. At the end of Phase III, half these replications were switched to the positive control diet and half were switched to the diet without the TMP but with phytase. In Exp. 1 during Phases II and III and in the overall data, pigs fed the diet without the TMP had decreased ADG and ADFI, but the addition of phytase prevented these responses (phytase x TMP; P < 0.02). Growth performance was not affected by diet during the growing-finishing period. Coccygeal bone Zn and Na concentrations were decreased (P < 0.09) in pigs fed the diet without the TMP, and adding phytase increased (P < 0.03) Zn and Fe concentrations. In Exp. 2 during Phases I and II, pigs fed the diet without the TMP had decreased ADG, but the addition of phytase prevented this response (phytase x TMP; P < 0.10). Pigs fed the diet without the TMP had decreased (P < 0.10) ADG (Phase II and overall), ADFI (Phases II and III and in the overall data), and G:F (Phase III). Coccygeal bone Zn and Cu concentrations were decreased (P < 0.09) in pigs fed the diet without the TMP, and adding phytase increased (P < 0.03) Zn concentration in the bones. These data indicate that removing the TMP in diets for nursery pigs decreases growth performance and bone mineral content, and that phytase addition to the diet without the TMP prevented the decreased growth performance.

Three experiments were conducted to determine the effects of phytase, excess Zn, or their combination in diets for nursery pigs. In all experiments, treatments were replicated with five to seven pens of six to seven pigs per pen, dietary Ca and available P (aP) levels were decreased by 0.1% when phytase was added to the diets, excess Zn was added as ZnO, a basal level of 127 mg/kg of Zn (Zn sulfate) was present in all diets, and the experimental periods were 19 to 21 d. In Exp. 1, pigs (5.7 kg and 18 d of age) were fed two levels of phytase (0 or 500 phytase units/kg) and three levels of excess Zn (0, 1,000, or 2,000 ppm) in a 2 x 3 factorial arrangement. Added Zn linearly increased ADG and ADFI during Phase 1 (P = 0.01 to 0.06), Phase 2 (P = 0.02 to 0.09), and overall (P = 0.01 to 0.02). Gain:feed was linearly increased by Zn during Phase 1 (P = 0.01) but not at other times. Dietary phytase decreased ADG in pigs fed 1,000 or 2,000 ppm Zn during Phase 2 (Zn linear x phytase interaction; P = 0.10), did not affect (P = 0.27 to 0.62) ADFI during any period, and decreased G:F during Phase 2 (P = 0.01) and for the overall (P = 0.07) period. Plasma Zn was increased by supplemental Zn (Zn quadratic, P = 0.01) but not affected (P = 0.70) by phytase addition. In Exp. 2, pigs (5.2 kg and 18 d of age) were fed two levels of phytase (0 or 500 phytase units/kg) and two levels of Zn (0 or 2,000 ppm) in a 2 x 2 factorial arrangement. Supplemental Zn increased ADG and G:F during Phase 2 (P = 0.02 to 0.09) and overall (P = 0.07 to 0.08), but it had no effect (P = 0.11 to 0.89) on ADG during Phase 1 or ADFI during any period. Phytase supplementation increased ADG (P = 0.06) and G:F (P = 0.01) during Phase 2. Gain:feed was greatest for pigs fed 2,000 ppm Zn and phytase (Zn x phytase interaction; P = 0.01). Bone (d 20) and plasma Zn (d 7 and 20) were increased (P = 0.01) by added Zn but not affected (P = 0.51 to 0.90) by phytase. In Exp. 3, pigs (5.7 kg and 19 d of age) were fed a basal diet or the basal diet with Ca and aP levels decreased by 0.10% and these two diets with or without 500 phytase units/kg. Supplemental phytase had no effect (P = 0.21 to 0.81) on growth performance. Reduction of dietary Ca and aP decreased (P = 0.02 to 0.08) ADG, ADFI, and G:F for the overall data. These results indicate that excess dietary supplemental Zn increases ADG and plasma and bone Zn concentrations. Dietary phytase did not affect plasma or bone Zn concentrations.

An experiment was conducted to determine the effects of phytase addition, reduced Ca and available P (aP), and removing the trace mineral premix (TMP) on growth performance, plasma metabolites, carcass traits, pork quality, and tissue mineral content in growing-finishing swine. One hundred twenty cross-bred pigs (initial and final BW of 22 and 109 kg, respectively) were allotted to five dietary treatments on the basis of weight within gender in a randomized complete block design. There were three replications of barrows and three replications of gilts, with four pigs per replicate pen. The dietary treatments were as follows: 1) corn-soybean meal (C-SBM), 2) C-SBM with reduced Ca and aP, 3) C-SBM with reduced Ca and aP plus 500 phytase units/kg of diet, 4) Diet 1 without the TMP, and 5) Diet 3 without the TMP. The Ca and aP were reduced by 0.10% in the low Ca and aP diets and the diets with added phytase. Daily gain, hot carcass weight, dressing percent, kilograms of carcass lean, bone ash percent, and bone strength were decreased (P = 0.10), but liver and kidney weight were increased (P = 0.10) in pigs fed diets with reduced Ca and aP; adding phytase reversed these responses (P = 0.10). The Commission Internationale de I'Eclairage L* was decreased (P = 0.09) in pigs fed the low Ca and aP diet plus phytase relative to those fed the control diet. Removing the TMP had no effect on overall growth performance, but it increased (P = 0.03) 10th-rib backfat thickness and fasting glucose and decreased (P = 0.03) carcass length and ham weight. Liver weight and liver weight as a percentage of final BW were not affected when phytase was added to the control diet, but removing the TMP increased liver weight and liver weight as a percentage of final BW; adding phytase reversed these responses (phytase x TMP, P = 0.06). Removing the TMP decreased (P = 0.08) Zn concentrations in the bone, muscle, and liver, and Cu and Fe concentrations in the bile but increased (P = 0.08) Mn concentrations in the bile and liver of pigs. The addition of phytase reversed the negative effects of the reduced Ca and aP diets. These data indicate that removing the TMP in diets for growing-finishing pigs has no negative effects on growth performance or pork quality, but it had negative effects on carcass traits and had variable effects on tissue mineral content.

Ninety-one primiparous and multiparous sows and their pigs were used to evaluate the effects of a novel carbohydrate- and protein-based feed ingredient (Nutri-Pal, NP) on sow and litter performance during lactation. Nutri-Pal is a feed supplement for sows that consists of a blend of milk chocolate, brewer's yeast, whey products, and glucooligosaccharides. The dietary treatments consisted of a corn-soybean meal control and a corn-soybean meal plus 5% NP fed from d 110 of gestation to weaning. The diets were formulated to be equal in total Lys and ME. Sows were allotted to treatment based on parity, body weight, and the date of d 110 of gestation. There were 46 and 45 sows per treatment over four farrowing groups. Litters were standardized to 10 pigs and weighed within 1 d of farrowing, and all sows weaned at least 8 pigs at an average age of 21 d. Sows were weighed on d 110 of gestation, d 1 postfarrowing, and at weaning. Sows were fed three times daily during lactation. Sows were checked twice daily after weaning for signs of estrus. The weaning weight of sows fed NP was increased (P 0.10) by diet. There were no effects (P > 0.10) of diet on litter performance response variables (pigs weaned, litter and average pig weaning weight and gain, and survival percent). The NP feed ingredient had minor effects on sow productivity, but it did not affect litter productivity indices.

Microbial phytase has been shown to increase the availability of Ca, P, ME, and amino acids (AA) in diets for broilers. However, much more research has been conducted on the Ca and P effects than on the ME and AA effects. Therefore, 2 experiments were conducted to evaluate the effect of phytase on the release of ME and AA from corn-soybean meal diets for broilers. Experiment 1 was a battery study that lasted for 14 d and included diets adequate in all nutrients, diets deficient in ME and AA, and these later 2 diets with and without added phytase. Experiment 2 was a floorpen study that lasted 42 d and included diets with reduced levels of ME and AA with added phytase. Growth performance, meat quality, and tibia ash were not affected by using the ME and AA values for phytase. Total P, soluble P, and inorganic soluble P in the litter were reduced when phytase was added to the diets. These data indicate that ME and AA values for phytase can be used in diet formulations for broilers with no loss in growth or yield performance, but a decrease in the P content of the litter will be observed.

Two experiments were conducted to determine the effect of nonwaxy (amylose and amylopectin starch) or waxy (amylopectin starch) sorghum on growth, carcass traits, and glucose and insulin kinetics of pigs. In Exp. 1 (95-d), 60 crossbred barrows or gilts (initial and final BW of 24 and 104 kg) were allotted to three treatments with five replications of four pigs per replicate pen in a randomized complete block design. The dietary treatments for Exp. 1 were 1) corn-soybean meal (C-SBM) diet, 2) sorghum-SBM (red pericarp, non-waxy), and 3) sorghum-SBM (red pericarp, waxy). In Exp. 2, 28 crossbred barrows (initial and final BW of 24 and 64 kg) were allotted to two treatments with three replications of four or five pigs per replicate pen in a randomized complete block design. Growth data were collected for 49 d, and then 20 barrows were fitted with jugular catheters, and then a glucose tolerance test (500 mg glucose/kg BW), an insulin challenge test (0.1 IU of porcine insulin/kg BW), and a feeding challenge were conducted. The dietary treatments for Exp. 2 were 1) sorghum-SBM (white pericarp, nonwaxy) and 2) sorghum-SBM (white pericarp, waxy). In Exp. 1, ADG (P = 0.10) and ADFI (as-fed basis; P = 0.02) were increased (P = 0.10) and gain:feed was decreased (P = 0.04) in pigs fed the sorghum-SBM diets relative to those fed the C-SBM diet. These responses may have resulted from the lower energy content of sorghum relative to corn. Plasma NEFA concentration (collected after a 16-h fast on d 77) was decreased (P = 0.08) in pigs fed the waxy sorghum-SBM diet relative to those fed the nonwaxy sorghum-SBM diet. Kilograms of carcass fat was decreased (P = 0.07) in pigs fed the waxy sorghum-SBM diet relative to those fed the nonwaxy sorghum-SBM diet. In Exp. 2, there was no effect (P = 0.57 to 0.93) of sorghum starch type on growth performance by pigs. During the glucose tolerance and insulin challenge tests, there were no effects (P = 0.16 to 0.98) of diet on glucose or insulin kinetics. During the feeding challenge, glucose (P = 0.02) and plasma urea N (P = 0.06) area under the response curves from 0 to 90 min were decreased in pigs fed the waxy sorghum-SBM diet. Feeding waxy sorghum had minimal effects on growth and carcass traits relative to pigs fed corn or nonwaxy sorghum. Waxy sorghum vs. nonwaxy sorghum had no effect on glucose or insulin kinetics in pigs.

Two experiments were conducted to determine the effect of phytase on plasma metabolites and AA and energy digestibility in swine. In Exp. 1, eight barrows (surgery BW = 52 kg) were fitted with steered ileocecal cannulas. The experiment was a Latin rectangle and the treatments were 1) corn-soybean meal diet adequate in Ca and P (0.5% Ca, 0.19% available P [aP]), 2) corn-soybean meal diet with reduced Ca and P (0.4% Ca, 0.09% aP), 3) Diet 1 with 500 phytase units/kg, or 4) Diet 2 with 500 phytase units/kg. Pigs were fed twice daily to a total daily energy intake of 2.6 x maintenance (106 kcal of ME/kg of BW(0.75)). For each ileal digesta sample, digesta samples were collected for two 24-h periods and combined for each pig. The combination of supplementing with phytase and decreasing the concentration of dietary Ca and P increased average ileal AA (P < 0.02), starch (P < 0.02), GE (P < 0.04), and DM (P < 0.03) digestibilities. In Exp. 2, a feeding challenge was conducted with barrows (eight per treatment; average BW of 53 kg). The treatments consisted of a corn-soybean meal diet or corn-soybean meal diet + 500 phytase units per kilogram of diet. In the diet with no phytase, Ca and aP were at 0.50% and 0.19%, respectively, and, in the diet with phytase, Ca and aP were each decreased by 0.12%. A catheter was surgically inserted into the anterior vena cava of each pig 6 d before the start of the feeding challenge. The barrows were penned individually, and the diets were fed for 3 d before the challenge. The pigs were held without feed for 16 h, and blood samples were obtained at -60, -30, and 0 min before the pigs were fed (2% of BW). Blood samples were then collected at 10, 20, 30, 40, 50, 60, 75, 90, 105, 120, 150, 180, 210, 240, 270, and 300 min after feeding. Glucose area under the response curve and plasma glucose, insulin, urea N, and total alpha-amino N concentrations were increased (P < 0.05) in pigs fed the diet with reduced Ca and P and the phytase addition. Area under the response curve for insulin, urea N, and total alpha-amino N; insulin:glucose; and plasma NEFA concentration, clearance, and half-life were not affected by diet. In conclusion, the combination of Ca and P reduction and phytase addition increased nutrient and energy digestibility in diets for pigs and increased plasma concentrations of glucose, insulin, urea N, and alpha-amino N.