Growth Performance Of Growing-finishing Pigs Research Articles

Effects of expanded diets and phase feeding programme on growth performance, carcass traits and meat quality in growing-finishing pigs

ABSTRACTTwo experiments were conducted to evaluate the effects of expanded diets and phase feeding programmes in growing-finishing pigs. In Exp. 1, a total of 72 pigs (25.88 ± 1.34 kg) were randomly allotted to 3 dietary treatments: (1) unexpanded corn–wheat–soybean meal (CWSBM)-based diets with two-phase feeding programme; (2) expanded CWSBM-based diets with two-phase feeding programme; (3) unexpanded CWSBM-based diets with three-phase feeding programme. During 12–14 weeks and 1–14 weeks, pigs offered the expanded diets had lower feed conversion ratio (FCR) compared with those fed unexpanded diets (P < .05). In Exp. 2, 120 growing pigs (20.51 ± 0.62 kg) were randomly assigned to 3 dietary treatments: (1) unexpanded corn–soybean meal (CSBM)-based diets with two-phase feeding programme; (2) expanded CSBM-based diets with two-phase feeding programme; (3) unexpanded CSBM-based diets with three-phase feeding programme. During 15–17 weeks, pigs fed expanded diets had increased daily gain and decreased FCR compared with those fed unexpanded diet (P < .05). In conclusion, expanded CWSBM- or CSBM-based diets improved growth performance of growing-finishing pigs. Phase feeding programmes did not affect growth performance, carcass characteristics and meat quality in growing-finishing pigs fed CWSBM- or CSBM-based diets.

Evaluation of ME predictions and the impact of feeding maize distillers dried grains with solubles with variable oil content on growth performance, carcass composition, and pork fat quality of growing-finishing pigs

A total of 432 pigs (initial BW: 25.8±5.1kg) were used to evaluate growth performance, carcass characteristics, and pork fat quality of growing-finishing pigs fed maize–soybean meal diets containing 40% distillers dried grains with solubles (DDGS) with variable ether extract (EE) content, but similar predicted ME concentration (3232 to 3315kcal/kg predicted by a commercial service). Pigs were blocked by initial BW, and within blocks, pens were allotted randomly to 1 of 4 dietary treatments (9 pigs/pen, 12 replicates/treatment) in a 4-phase feeding program (26–50kg, 50–75kg, 75–100kg, and 100–120kg BW). Dietary treatments consisted of: (1) maize–soybean meal (CON); (2) 40% low-oil DDGS (59g/kg EE; LOW); (3) 40% medium-oil DDGS (99g/kg EE; MED); and (4) 40% high-oil DDGS (142g/kg EE; HIGH). Diets contained similar concentrations of standardized ileal digestible amino acids and standardized total tract digestible P within each phase. Overall, ADFI of pigs fed CON was greater (P<0.05) than those fed MED and HIGH, resulting in pigs fed CON having greater (P<0.05) overall ADG than pigs fed LOW, MED, and HIGH diets. However, ADFI and ADG did not differ among DDGS treatments, but pigs fed LOW had reduced (P<0.05) G:F compared with the other treatments. Pigs fed CON had greater (P<0.05) HCW, carcass yield, and LM area than those fed the DDGS diets, but there were no differences among DDGS treatments. No treatment differences were observed for backfat depth and percentage of carcass fat-free lean. Back, belly, and jowl fat iodine value of pigs fed LOW and MED were less (P<0.01) than in pigs fed HIGH but greater (P<0.01) than in pigs fed CON. Based on the observed overall G:F responses, dietary ME content of LOW was less than MED, HIGH, and CON diets, indicating a slight overestimation of predicted ME concentration for the low-oil DDGS source using either the commercial service estimates or the Anderson et al. (2012) equations. In conclusion, including 40% DDGS in maize–soybean meal-based diets negatively impacted the growth performance of growing-finishing pigs. However, reduced EE content of DDGS sources did not affect ADG, ADFI, and carcass composition, and led to improvements in pork fat quality. These results suggest that current ME predictions need to be refined for more accurate estimation of ME content for low-oil DDGS sources for swine.

Low-protein diets affect ileal amino acid digestibility and gene expression of digestive enzymes in growing and finishing pigs.

The objective of this study was to evaluate effects of dietary crude protein (CP) intake on ileal amino acid digestibilities and expression of genes for digestive enzymes in growing and finishing pigs. In Experiment 1, 18 growing pigs (average initial BW = 36.5 kg) were assigned randomly into one of three treatments (n = 6/treatment group) representing normal (18 % CP), low (15 % CP), and very low (12 % CP) protein intake. In Experiment 2, 18 finishing pigs (average initial BW = 62.3 kg) were allotted randomly into one of three treatments (n = 6/treatment group), representing normal (16 % CP), low (13 % CP) and very low (10 % CP) protein intake. In both experiments, diets with low and very low CP were supplemented with crystalline amino acids to achieve equal content of standardized ileal digestible Lys, Met, Thr, and Trp, and were provided to pigs ad libitum. Daily feed intake, BW, and feed/gain ratios were determined. At the end of each experiment, all pigs were slaughtered to collect pancreas, small-intestine samples, and terminal ileal chymes. Samples were used for determining expression of genes for digestive enzymes and ileal amino acid digestibilities. Growing pigs fed the 12 % CP and 15 % CP diets had lower final body weight (P < 0.01) and ADG (P < 0.0001) when compared with pigs fed the 18 % dietary CP diet. Growing pigs fed with the 12 % CP diet showed higher digestibilities for CP (P < 0.05), DM (P < 0.05), Lys (P < 0.0001), Met (P < 0.01), Cys (P < 0.01), Thr (P < 0.01), Trp (P < 0.05), Val (P < 0.05), Phe (P < 0.05), Ala (P < 0.05), Cys (P < 0.01), and Gly (P < 0.05) than those fed the 18 % CP diet. Finishing pigs fed the 16 % CP diet had a higher (P < 0.01) final body weight than those fed the 10 % CP diet. mRNA levels for digestive enzymes (trypsinogen, chymotrypsin B, and dipeptidases-II and III) differed among the three groups of pigs (P < 0.05), and no difference was noted in the genes expression between control group and lower CP group. These results indicated that a reduction of dietary CP by a six-percentage value limited the growth performance of growing-finishing pigs and that a low-protein diet supplemented with deficient amino acids could reduce the excretion of nitrogen into the environment without affecting weight gain.

Influence of Rapeseed Meal on Growth Performance, Blood Profiles, Nutrient Digestibility and Economic Benefit of Growing-finishing Pigs.

This study was conducted to investigate the influence of dietary rapeseed meal (RSM) on growth performance, blood profiles, nutrient digestibility and economic benefit of growing-finishing pigs. A total of 120 growing pigs ([Yorkshire×Landrace] ×Duroc) with an initial body weight (BW) 29.94±0.06 kg were used in this experiment. Pigs were randomly allotted into 1 of 5 treatments in a randomized complete block design and 6 replicates with 4 pigs per pen. Treatments were divided by dietary RSM supplementation levels (0%, 3%, 6%, 9%, or 12%) in growing-finishing diets. A linear decrease (p<0.05) of BW and average daily gain (ADG) were observed at 13th wk of finishing and overall periods of pigs. Additionally, gain-to-feed ratio (G/F) tended to decrease by dietary RSM supplementation in growing-finishing diets (linear, p = 0.07 and quadratic, p = 0.08). Concentrations of serum triiodothyronine and thyroxine were not influenced by dietary RSM treatments whereas thyroid gland and liver weight were increased at 13th wk of finishing period (linear, p<0.05; p<0.01) by increasing dietary RSM supplementation level. In blood profiles, serum total cholesterol and low density lipoprotein cholesterol concentrations were not differed by dietary treatments at 13th wk of finishing period whereas concentration of serum high density lipoprotein cholesterol was affected by the supplementation level of RSM, resulting in a linear RSM level responses (p<0.05). Serum blood urea nitrogen concentration tended to decrease (linear, p = 0.07; p = 0.08) at 6th wk of growing and 13th wk of finishing periods and digestibility of dry matter tended to decrease by dietary RSM (linear, p = 0.09). Crude protein, crude fat and nitrogen retention, whereas, were not affected by dietary RSM supplementation level. In the economic analysis, feed cost per weight gain was numerically decreased when RSM was provided up to 9%. Consequently, RSM could be supplemented to growing-finishing diets up to 9% (3.07 μmol/g Gls) without detrimental effects on growth performance of growing-finishing pigs.

Effects of dietary sulfur and distillers dried grains with solubles on carcass characteristics, loin quality, and tissue concentrations of sulfur, selenium, and copper in growing-finishing pigs.

Inclusion of up to 0.38% S in diets that contain 30% distillers dried grains with solubles (DDGS) has no negative effect on growth performance of growing-finishing pigs, but there is no information about the effects of dietary S on accumulation of S in tissues in pigs. Therefore, the objective of this experiment was to determine if the concentration of S in diets containing DDGS affects carcass characteristics, loin quality, or tissue mineral concentrations in growing-finishing pigs. A total of 120 barrows (34.2 ± 2.3 kg BW) were allotted to 3 dietary treatments with 10 replicate pens and 4 pigs per pen in a randomized complete block design. Pigs were fed grower diets for 42 d and finisher diets for 42 d. At the conclusion of the experiment, the pig in each pen with the BW closest to the pen average was slaughtered. The control diet was based on corn and soybean meal and the finisher diet contained 0.14% S, 0.19 mg/kg Se, and 15.3 mg/kg Cu. The DDGS diet was formulated with corn, soybean meal, and 30% DDGS and the finisher diet with DDGS contained 0.16% S, 0.32 mg/kg Se, and 14.0 mg/kg Cu. The DDGS plus S (DDGS-S) diet was similar to the DDGS diet, except that 1.10% CaSO4 (16.2% S) was included in this diet, and the finisher diet with DDGS-S contained 0.37% S, 0.35 mg/kg Se, and 13.8 mg/kg Cu. Results indicated that organ weights and loin quality, 24-h pH, drip loss, loin subjective color, marbling, and firmness did not differ among treatments, but loin a* was greater (P < 0.05) for pigs fed the control diet than for pigs fed the DDGS-S diet. Concentrations of S in hair, liver, heart, loin, and all other tissues did not differ among treatments, but urinary S concentration was greater (P < 0.05) for pigs fed the DDGS-S diet than for pigs fed the other diets. Pigs fed the DDGS diet or the DDGS-S diet had greater (P < 0.01) concentrations of Se in hair, liver, heart, and loin than pigs fed the control diet, but liver concentrations of Cu did not differ among treatments. In conclusion, inclusion of 30% DDGS in diets fed to growing-finishing pigs did not influence carcass characteristics or tissue S concentrations regardless of S concentration in the diet, and excess dietary S was excreted in the urine. However, because of the greater concentration of Se in DDGS than in corn and soybean meal and, therefore, greater concentrations in DDGS-containing diets, tissue concentrations of Se were increased in pigs fed diets that contained DDGS. In contrast, dietary DDGS did not influence liver concentrations of Cu.

Effects of corn DDGS in combination with compound enzymes on growth performance, carcass fat quality, and plasma and tissue redox homeostasis of growing-finishing pigs

The trial was conducted to investigate effects of corn dried distillers grains with soluble (DDGS) and compound enzymes on growth performance, carcass fat quality, and plasma and tissue redox homeostasis in growing-finishing pigs. 200 Pigs (Duroc×Landrace×Yorkshire, about 30kg BW) were randomly allotted to one of four treatment groups (5pens/treatment and 10pigs/pen). The control (T0) was fed a basal corn-soybean meal diet. Treatment 1 (T1), 2 (T2), and 3 (T3) were fed corn-soybean meal-DDGS diets, with 10% corn DDGS in growing phase and 15% in finishing phase, respectively. 0.2g/kg compound enzymes were added to the diets of T2 and T3 and digestible energy (DE) level of T3 was reduced 0.21MJ/kg. The results of growth performance showed that all groups had comparable (P>0.05) results on ADG (682.15g, 671.99g, 709.28g, 700.29g), ADFI (2.00kg, 2.02kg, 2.04kg, 2.10kg) and feed conversion ratio (2.94, 3.01, 2.88, 3.00). Nevertheless, DDGS containing diets significantly increased iodine value (P<0.05) and decreased fat melting point of backfat and belly fat (P<0.05). For backfat and longissimus muscle (LM) intramuscular fat, DDGS containing diets increased unsaturated fatty acids (UFA) content (especially oleic acid and linoleic acid) (P<0.05), while decreased saturated fatty acids (SFA) content (especially palmitic acid and stearic acid) (P<0.05) and SFA:UFA ratio (P<0.05). Furthermore, DDGS containing diets reduced antioxidant activity of plasma and tissue. The activity of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and total antioxidative capacity (T-AOC) of plasma decreased in T1, T2 and T3 compared to T0, while malondialdehyde (MDA) content increased, especially in T3 (P<0.05). DDGS containing diets slightly decreased the activity of GSH-Px, SOD and T-AOC in liver and cardiac muscle (especially T3), while increased MDA content of kidney and spleen significantly (P<0.05). In conclusion, although there were no negative effects on the growth performance of growing-finishing pigs, DDGS containing diets decreased carcass fat quality by increasing iodine value and UFA content in backfat and LM intramuscular fat and decreasing fat melting point and SFA:UFA ratio, and altered the redox homeostasis of plasma and tissue by increasing oxidant (MDA) content and decreasing antioxidant content. Furthermore, adding compound enzymes to DDGS containing diets tended to increase the ADG of growing-finishing pigs.

Effects of diet form and fiber withdrawal before marketing on growth performance of growing-finishing pigs (2012)

A total of 288 pigs (PIC 327 × 1050, initially 109.3 lb BW) were used in an 81-d trial to determine the effects of diet form and fiber (from dried distillers grains with solubles [DDGS] and wheat middlings) withdrawal before harvest on growth performance of growing-finishing pigs. Treatments were arranged in a 2 × 3 factorial with the main effects of diet form and dietary fiber feeding regimen. The 2 diet forms were meal or pellet. The 3 fiber feeding regimens were (1) low dietary fiber (corn-soybean meal–based diets) from d 0 to 81, (2) high dietary fiber (30% DDGS and 19% wheat midds) from d 0 to 64 followed by low fiber from d 64 to 81 (fiber withdrawal), and (3) high dietary fiber from d 0 to 81.

Effects of feeder design (conventional dry vs. wet-dry) on growth performance of 45- to 246-lb pigs (2012)

A total of 1,253 pigs (PIC 1050 × 337; initially 45 lb) were used in a 104-d study to evaluate the effects of using a wet-dry (WD) or conventional dry (CD) feeder on growth performance of growing-finishing pigs. At the start of the trial, pens of pigs were weighed and randomly allotted to 1 of the 2 feeder types. The CD feeder was a single-sided, 56-in.-wide, stainless steel feeder (Thorp Equipment, Inc., Thorp, WI) with 4 14-in. feeding spaces and a 4.25-in.-deep trough. A cup waterer in pens using CD feeders ensured ad libitum access to water as well as feed. The WD feeder was double-sided (15-in.-wide feeder opening on each side) with a single nipple waterer (Crystal Springs, GroMaster, Inc., Omaha, NE), and the feeder was the only source of water. All pigs were fed the same corn-soybean meal diets containing 30% bakery by-product and 10 to 45% dried distillers grains with solubles (DDGS) during 5 dietary phases. For the overall period, pigs fed with the WD feeder had greater ADG (P < 0.01) and ADFI (P = 0.01) with no differences in F/G (P = 0.50) compared with pigs fed using the CD feeder. This study confirms previous results where pigs fed using a WD feeder have greater ADG and ADFI than those fed with a CD feeder.; Swine Day, Manhattan, KS, November 15, 2012

Effects of diet form and feeder adjustment on growth performance of growing-finishing pigs (2012)

Effects of diet form and feeder adjustment on growth performance of growing-finishing pigs (2012)

Effects of increasing dietary bakery by-product on growing-finishing pig growth performance and carcass quality (2012)

A total of 1,263 pigs (PIC 337 × 1050; initially 77.8 lb) were used in a 102-d study to determine the effects of dietary bakery by-product on pig growth performance and carcass quality. Pigs were randomly assigned to pens based on gender (14 barrow pens, 11 gilt pens, and 23 mixed-gender pens). Pens of pigs were allotted to 1 of 3 dietary treatments in a completely randomized design while balancing for initial BW and gender. Dietary treatments included 0, 7.5, and 15% bakery by-product. On d 84, the 5 heaviest pigs from each pen (determined visually) were sold according to the normal marketing procedure of the farm. On d 102, the remaining pigs were individually tattooed by pen number and sent to harvest to allow for collection of carcass data. On d 84 and d 102, the median weight market pig from every pen was selected (determined visually) for collection of carcass quality measurements.

Effects of farrowing system on behavior and growth performance of growing-finishing pigs

A study was conducted to compare growth performance and behaviors of group-farrowed pigs with those of confinement-farrowed pigs. A total of 216 pigs (8 wk of age) were used, with an equal number of group-farrowed or confinement-farrowed pigs from 1 farrowing batch. Group-farrowed pigs were farrowed in bedded, individual pens and mingled into a group of 8 litters at 12 (±1.3) d of age. Pigs were weaned at 33 (±1.3) d and remained in the farrowing room until 8 wk of age. Confinement-farrowed pigs were farrowed in farrowing crates. At weaning (32 ± 2.0 d of age), confinement-farrowed pigs were mixed and moved to pens of 9 pigs in a confinement nursery and remained there until 8 wk of age. At 8 wk of age, pigs from the 2 housing systems were allocated to 24 pens of 9 pigs in a confinement growing-finishing barn, with 12 pens from each of the housing systems. Within farrowing system, pigs from different groups or pens were mixed upon entering the growing-finishing barn. Individual BW was recorded at allotment (wk 0) to the growing-finishing barn and every 2 wk thereafter for 14 wk. Feed intake and G:F were monitored on a pen basis every 2 wk between wk 0 and 14 of the study period. Behaviors of pigs were video recorded in 6 pens of each housing treatment for 24 h on the day of mixing (d 0), d 7, and d 14 after mixing in the finisher barn. The video recordings were scanned at 5-min intervals to calculate behavioral time budgets for lying, standing, eating, drinking, and belly nosing. Data were analyzed using the Proc Mixed model of SAS with repeated measures. Compared with confinement-farrowed pigs, group-farrowed pigs spent more time lying (85.7 vs. 82.7%; SE = 0.75; P < 0.001) and belly nosing (0.05 vs. 0.02%; P < 0.05) and less time standing (5.8 vs. 7.5%; SE = 0.49; P < 0.01) and eating (7.3 vs. 9.3%; SE = 0.40; P < 0.001). The difference in behavioral time budgets was associated with differences in performance of pigs from the 2 housing systems. Group-farrowed pigs exhibited greater ADG (866 vs. 814 g; SE = 10.3; P < 0.01) for the initial 2 wk after mixing, less ADFI (2,004 vs. 2,188 g; SE = 42.5; P < 0.05), and improved G:F (0.431 vs. 0.393; SE = 0.0078; P < 0.01) for the entire 14-wk study period compared with confinement-farrowed pigs. These results suggest that group-farrowed pigs were more efficient than confinement-farrowed pigs in utilizing dietary energy for BW gain by lying more and standing and eating less during the growing and finishing period.

A meta-analysis of the effects of high ambient temperature on growth performance of growing-finishing pigs

High ambient temperature (T) is one of the most important climatic factors influencing pig performance. Increased T occurs sporadically during summer heat waves in temperate climates and year round in tropical climates. Results of published experiments assessing the effects of high T on pig performance are surprisingly variable. Thus, a meta-analysis was performed to aggregate our knowledge and attempt to explain differences in the results across studies on the effect of increased T on ADFI and ADG in growing-finishing pigs. Data for ADFI and ADG were extracted from 86 and 80 trials, respectively, from articles published in scientific journals indexed in PubMed, Science Direct, and from proceedings of scientific meetings through November 2009. Data on ADFI and ADG were analyzed using a linear mixed model that included the linear and the quadratic effects of T and BW, and their interactions as continuous, fixed effects variables, and the trial as a random effect factor (i.e., block). In addition, the effects of housing type (2 levels: individual and group housing) and the year of publication (3 levels: 1970 to 1989, 1990 to 1999, and 2000 to 2009) on the intercept and the linear regression term for T (i.e., the slope) were also tested. Results showed that high T had a curvilinear effect on ADFI and ADG and that this effect was more pronounced in heavier pigs. Across T, ADFI was less when pigs were group-housed. The intercept and the regression coefficient (slope) for T were significantly affected by the year of publication. The effect of increased T was greater in more contemporary works, suggesting that modern genotypes could be more sensitive to heat stress than older genotypes of lesser growth potential. In conclusion, pig performance decreases at an accelerating rate as T is increased. The large between-study variability on the effects of high T on pig performance is partially explained by differences in pig BW and to a lesser extent by the year the study was published.

Effects of Supplemental Enzymes in Diets Containing Distillers Dried Grains with Solubles on Finishing Pig Growth Performance

ABSTRACT Four experiments involving 4,506 pigs were conducted to determine the effects of different commercial enzymes on the growth performance of growing-finishing pigs fed distillers dried grains with solubles (DDGS). All experiments were conducted in the same commercial swine research facility. Experiments 1 and 2 used corn- and soybean meal-based diets with 15% DDGS. A β-mannanase enzyme was used in Exp. 1, and a blend of enzymes that contained β-glucanase, cellulase, and protease activities was used in Exp. 2. There were no differences (P > 0.10) in ADG, ADFI, and G:F between pigs fed diets with added enzyme and pigs fed diets without enzyme in either experiment (ADG 1.00 vs. 1.01 kg/d, and G:F 0.408 vs. 0.408; ADG 0.94 vs. 0.94 kg/d, and G:F 0.424 vs. 0.421, in Exp. 1 and 2, respectively) In Exp. 3, diets containing 45 and 60% DDGS were fed with or without 2 commercial proprietary enzyme products designed for use in diets containing DDGS. Average daily gain (0.85 vs. 0.86 kg/d) and G:F (0.370 vs. 0.373) were not different (P > 0.10) among treatments. In Exp. 4, an enzyme product with bacterial endo-1,4-β-xylanase was evaluated in diets containing 30% DDGS. Average daily gain (0.82 vs. 0.82 kg/d) and G:F (0.391 vs. 0.387) were not different (P > 0.10) among treatments. Based on the results, the different enzymes evaluated in these experiments did not enhance finishing pig growth performance when diets contained varying levels of DDGS.

Effects of feeder design and feeder adjustment on the growth performance of growing-finishing pigs (2010)

Two experiments were performed to evaluate the effects of feeder design (conventional dry feeder vs. wet-dry feeder) and adjustment on growing-finishing pig performance. In both experiments, all pigs (PIC 337 × 1050) were fed the same corn-soybean meal diets with 15% dried distillers grains with solubles (DDGS). In Exp. 1, 1,296 pigs (initially 43 lb) were used in a 69-d study. From d 0 to 27, 3 feeder settings were evaluated for each feeder type. Numbered settings (located in each feeder) were 6, 8, and 10 for the conventional dry feeder and 6, 10, and 14 for the wet-dry feeder. An increased setting number corresponded to a greater opening. From d 27 to 69, all feeders were adjusted to an opening of approximately 1 in. (conventional dry feeder setting 8; wet-dry feeder setting 14). From d 0 to 27, pigs using a wet-dry feeder had lower (P < 0.02) ADFI and better F/G than pigs using a conventional dry feeder. Increasing the feeder setting improved (linear, P < 0.01) ADG, ADFI, and d-27 BW of pigs using a wet-dry feeder and increased (linear, P < 0.01) ADFI of pigs using a conventional dry feeder. From d 27 to 69, ADG and ADFI of pigs using a wet-dry feeder were greater (P < 0.01) than those of pigs using a conventional dry feeder, and increasing the feeder setting from d 0 to 27 resulted in greater (linear, P < 0.01) ADFI and poorer F/G for pigs using a wet-dry feeder. Overall (d 0 to 69), pigs using a wet-dry feeder had greater (P < 0.05) ADG, ADFI, final BW, and better F/G than pigs that used a conventional dry feeder. Increasing the feeder setting of a wet-dry feeder from d 0 to 27 resulted in greater (linear, P < 0.01) ADG and ADFI, poorer (linear, P < 0.03) F/G, and heavier (linear, P < 0.01) final BW. Feeder setting of a conventional dry feeder from d 0 to 27 did not affect overall performance. In Exp. 2, 1,248 pigs (initially 73 lb) were used in a 93-d study. Three feeder settings were evaluated throughout the study for each feeder type (conventional dry feeder set at 6, 8, and 10; wet-dry feeder set at 10, 14, and 18). Overall, pigs using a wet-dry feeder had greater (P < 0.05) ADG, ADFI, final BW, HCW, backfat depth, and feed cost but reduced (P < 0.04) fat-free lean index (FFLI) compared with pigs using a conventional dry feeder. Increasing the feeder setting of a wet-dry feeder resulted in greater (linear, P < 0.05) ADG, ADFI, final BW, HCW, backfat depth, and feed cost. When HCW was used as a covariate, FFLI of pigs using a wet-dry feeder decreased (linear, P < 0.02) with increased feeder opening. Increasing the feeder setting of a conventional dry feeder had no effect on growth performance and carcass characteristics. In conclusion, the growth rate of pigs improved with a wet-dry feeder compared with a conventional dry feeder; however, the growth of pigs using a wet-dry feeder was more sensitive to differences in feeder adjustment.

Effects of dried distillers grains with solubles and increasing dietary wheat middlings on growth performance, carcass characteristics, and fat quality in growing-finishing pigs (2010)

A total of 288 pigs (PIC TR4 × 1050, initially 100 lb) were used in an 84-d growth trial to evaluate the effects of dietary wheat middlings and dried distillers grain with solubles (DDGS) on growing-finishing pig growth performance, carcass characteristics, and carcass fat quality. Pens of pigs were balanced by initial weight and gender and were randomly allotted to 1 of 4 dietary treatments with 8 pigs per pen (4 barrows and 4 gilts) and 9 replications per treatment. Dietary treatments included a corn-soybean meal-based diet, a diet with 30% DDGS, or the diet with 30% DDGS with 10% or 20% wheat middlings. Treatment diets were formulated to constant standardized ileal digestible lysine:ME ratios within each phase. All treatments were fed in 4 phases. Overall (d 0 to 84), pigs fed increasing wheat middlings had decreased (linear; P ≤ 0.02) ADG and poorer (linear; P ≤ 0.01) F/G. There were no differences (P = 0.12) among treatments for ADFI. For carcass characteristics, increasing wheat middlings decreased (linear; P < 0.01) percentage yield and HCW and tended to decrease (linear; P < 0.06) loin depth. Pigs fed wheat middlings also had decreased (quadratic; P < 0.02) back fat and increased (quadratic; P < 0.01) percentage lean. Increasing DDGS from 0 to 30% decreased (P < 0.03) carcass yield and backfat depth (P < 0.01), while increasing percentage lean (P < 0.03) and jowl iodine value (P < 0.001).

A meta-analysis of supplemental enzyme studies in growing-finishing pigs fed diets containing dried distillers grains with solubles: effects on growth performance (2009)

A meta-analysis of 4 experiments involving 4,506 pigs was conducted to determine the effects of several commercial enzymes on the growth performance of growing-finishing pigs fed various amounts of dried distillers grains with solubles (DDGS). Experiments 1 and 2 used corn-soybean meal-based diets with 15% DDGS. A β-mannanase enzyme (Hemicell; ChemGen Corp., Gaithersburg, MD) was used in enzyme treatments in Exp. 1, and a blend of enzymes that had β-glucanase, cellulase, and protease activities (Agri-king REAP; Agri-King, Inc., Fulton, IL) was used in Exp. 2. In Exp. 3, diets containing 45% and 60% DDGS were fed with or without 2 commercial enzyme products designed for use in diets containing DDGS. In Exp. 4, an enzyme product with bacterial endo-1,4-β-xylanase was evaluated in diets containing 30% DDGS. All enzyme treatments in each experiment were pooled in a meta-analysis to compare the responses to diets with or without enzyme addition regardless of the other factors tested in each trial. All experiments were conducted in the same commercial swine research facility. There were no differences in ADG (P > 0.52), ADFI (P > 0.33), F/G (P > 0.35), and final weight (P > 0.60) among pigs fed diets with added enzyme and pigs fed diets without enzyme in any of the 4 experiments or in the pooled data. In conclusion, on the basis of the combined results from the 4 experiments evaluated in this meta-analysis, adding these enzymes in diets containing various amounts of DDGS does not appear to be beneficial in pigs.; Swine Day, Manhattan, KS, November 19, 2009

Effects of increasing standardized ileal digestible lysine:calorie ratio on the growth performance of growing-finishing pigs (2009)

A total of 1,080 pigs (PIC TR4 × 1050) were used in four 28-d experiments to determine the lysine requirements of growing-finishing pigs reared in the new Kansas State University finishing barn. Low- and high-lysine corn-soybean meal-based diets with no added fat were formulated for each experiment by varying the amounts of corn, soybean meal, L-lysine HCl, DL-methionine, and L-threonine. Six lysine levels were evaluated in each experiment, with intermediate lysine levels obtained by blending the low- and high-lysine diets. There were 6 pens containing an equal number of barrows and gilts for each treatment, with 6 or 8 pigs per pen. Pens were blocked by initial count and BW. In Exp. 1, 252 pigs (initially 80.7 lb) were fed diets with standardized ileal digestible lysine:calorie (SID lys:cal) ratios of 2.09, 2.39, 2.69, 2.99, 3.29, or 3.59 g/Mcal ME. Increasing the SID lys:cal ratio improved (linear; P < 0.04) ADG and F/G. Optimum performance and income over feed cost (IOFC) was observed at 2.69 g SID lys/Mcal, or a dietary level of 1.01% total lysine and 0.90% SID lysine. In Exp. 2, 288 pigs (initially 122.9 lb) were fed diets with SID lys:cal ratios of 2.12, 2.35, 2.58, 2.81, 3.04, or 3.27 g/Mcal. Increasing the SID lys:cal ratio tended (quadratic; P < 0.12) to increase ADG and improved (linear; P < 0.02) F/G. Optimum performance and IOFC was observed at 2.35 g SID lys/Mcal, or a dietary level of 0.88% total and 0.78% SID lysine. In Exp. 3, 252 pigs (initially 177.2 lb) were fed diets with SID lys:cal ratios of 1.49, 1.79, 2.09, 2.39, 2.69, or 2.98 g/Mcal. Increasing the SID lys:cal ratio tended (linear; P < 0.06) to improve ADG and improved (linear; P < 0.001) F/G. Optimum performance and IOFC was observed at 2.09 g SID lys/Mcal, or a dietary level of 0.80% total and 0.70% SID lysine. In Exp. 4, 288 pigs (initially 224.3 lb) were fed the same SID lys:cal ratios as in Exp. 3. Increasing the SID lys:cal ratio decreased (linear; P < 0.04) ADFI, F/G, carcass yield, and IOFC. Despite a linear improvement in F/G, ADG did not improve above 1.79 g SID lys/Mcal, which resulted in the best IOFC. This requirement is equivalent to 0.69% total and 0.60% SID lysine. These experiments agree with previous recommendations for growing-finishing pigs of this genotype. For pigs weighing 80 to 143 lb, 123 to 190

Effect of liquid feeding at different water-to-feed ratios on the growth performance of growing-finishing pigs

The study examined the growth performance of pigs offered liquid feed or dry feed on either a restricted or an ad libitum basis, and whether their growth performance was further influenced by the water-to-feed ratio. The study was split into two parts to enable unrestricted (trial 1; n = 64) and restricted (trial 2; n = 48) feeding to be compared. Male pigs were randomly allocated to six dietary treatment groups. A standard dry pellets diet (D) was offered either as: (i) unrestricted ration (UR); (ii) restricted ration (R); or D soaked in water at a feed-to-water ratio of (iii) 1 : 1.5 restricted (1 : 1.5 R); (iv) 1 : 3 unrestricted (1 : 3 UR); (v) 1 : 3 restricted (1 : 3 R); or (vi) 1 : 3 restricted with the addition of lactic acid to adjust the feed to pH 4 (1 : 3(4) R). Liquid feeding improved (P < 0.05) average daily live-weight gain (ADG) and lean tissue growth rate (LTGR) in the 1 : 3 UR compared with DUR but did not alter feed conversion ratio (FCR). Within the R groups, ADG were greater in all of the 1 : 3 diets, whereas feed intake, and hence FCR, was lower (P < 0.001) in these groups when offered the R ration. In conclusion, liquid feeding has a beneficial influence on the performance of modern porcine genotypes during the growth/finishing phase and this is further modulated by the water-to-feed ratio.

Influence of Rearing Environment and Season on Growth Performance of Growing-Finishing Pigs

An eight-year study was conducted to determine the effects of three different rearing environments on growth performance of growing and finishing pigs (from 28 to 107 kg avg. body wt.) reared during the summer or winter in the southeastern U.S. (31 °N latitude). The three rearing environments were two outside dirt lot types with minimal shelter that (1) had (old) or (2) had not (new) been occupied previously by pigs, and (3) concrete-floored pens in a semi-confinement building. Two trials were conducted each year (summer and winter), and each involved 36 crossbred pigs. All pigs were routinely dewormed. Overall, pigs reared during the summer on average grew 3% slower (0.83 vs. 0.86 kg/d; P < 0.001) but required 3% less feed (3.32 vs. 3.41 kg/kg; P < 0.001) per unit of gain than pigs raised during the winter. Rearing environment influenced average daily gain (0.82, 0.85, and 0.86 kg/d for old, new, and concrete pens, respectively; P < 0.001) and feed/gain (3.48, 3.35, and 3.26 kg/kg; P < 0.001). A pen x season interaction (P < 0.01) was noted for feed/gain. Average backfat thickness was influenced by rearing environment (P = 0.01) and somewhat by season (P = 0.08). Growing-finishing pigs can be effectively reared on outside dirt lots under the environmental conditions of the southeastern U.S., in particular if the lots are periodically rotated to new ground.

Effects of increasing amounts of true ileal digestible lysine on the growth performance of growing-finishing pigs reared in a commercial facility (2006)

Two 28-d experiments using 2,259 gilts were conducted to determine the growth and economic effects of increasing dietary true ileal digestible (TID) lysine in commercially reared growing-finishing pigs. Both experiments included 6 dietary treatments of incrementally increasing TID lysine in diets containing 6% added fat. The dietary TID lysine ranged from below to above our current requirement estimates to determine if there were any changes in lysine requirements during the past five years. In Exp. 1, pigs were initially 132 lb and averaged 192 lb at the end of the 28-day study. The TID lysine rates were 0.65, 0.75, 0.85, 0.95, 1.05, and 1.15%, which corresponded to lysine:calorie ratios of 1.80, 2.08, 2.35, 2.63, 2.91, and 3.19 g/Mcal, respectively. Increasing TID lysine increased ADG (linear, P<0.01) and improved F/G (quadratic, P<0.06), with optimal performance at 1.05% TID lysine (TID lysine:ME ratio of 2.91 g/Mcal). Pigs fed this diet consumed approximately 22 g of TID lysine per day, and used 21.6 g of TID lysine/kg of gain. Although not significant, margin over feed cost (MOF) was numerically greatest for pigs fed 1.05% TID. In Exp. 2, pigs were initially 177 lb and averaged 241 lb at the end of the 28-d study. The TID lysine rates were 0.52, 0.62, 0.72, 0.82, 0.92, and 1.02%, which corresponded to lysine:calorie ratios of 1.44, 1.71, 1.99, 2.27, 2.55, and 2.83 g/Mcal, respectively. In Exp. 2, the optimal TID lysine rate changed over the course of the experiment. During the first 14 d, pigs fed 0.92% TID lysine had the greatest ADG and lowest F/G, whereas pigs fed 0.72% TID lysine had the numerically highest ADG and lowest F/G from d 14 to 28. Pigs fed these diets required approximately 19.5 g of TID lysine/kg gain. Margin over feed costs increased (quadratic, P<0.03) with increasing dietary TID lysine, with the greatest return at 0.72% TID lysine. In summary, results of the first experiment suggest an increase in dietary TID lysine recommendations, compared with our earlier studies. Even though the optimal lysine rate may be changing over time for this genetic line and production facility, it seems that using the estimate of approximately 20 g TID lysine per kg of gain will provide a good estimate of the pig’s lysine requirement.; Swine Day, 2006, Kansas State University, Manhattan, KS, 2006