Improvement In ADG Research Articles

358 The effect of increasing dietary limestone concentration on growth performance, gas flux, and carcass characteristics in finishing beef cattle

Abstract Reducing methane (CH4) emissions from beef cattle is desirable as CH4 is a greenhouse gas that represents an energetic loss from the production system. Limestone is commonly fed to cattle as a source of calcium but may also act as a rumen buffer and decrease CH4 emissions by limiting hydrogen availability for methanogenesis. The objective of this experiment was to determine if diet limestone concentration influences growth performance, gas flux, and carcass characteristics in finishing beef cattle. Yearling steers [n = 16; initial body weight (BW) 619 ± 34 kg] were stratified by BW and randomly assigned to 1 of 2 isocaloric and isonitrogenous dietary treatments in a completely randomized design where limestone was included at 1.3% (1X) or 2.6% (2X) of diet dry matter (DM). Finishing diets were formulated to contain 0.43 or 0.96% DM as Ca and were fed ad libitum using automated cattle feeders (SmartFeed Pro; C-Lock Inc.; Rapid City, SD) in a single pen for the final 37 d of finishing. Body weights were measured on d -1, 0, 36, and 37. An automated head chamber system (GreenFeed; C-Lock Inc.) was used to measure gas flux. Analysis of variance was conducted using JMP Pro 17 to determine the fixed effect of treatment with individual animal as the experimental unit. Statistical significance was defined as P ≤ 0.05 with a tendency defined as 0.05 < P ≤ 0.10. Increasing the dietary limestone concentration from 1.3 to 2.6% of DM did not influence DM intake, but numerically increased final shrunk BW (P = 0.68) and hot carcass weight (P = 0.75) and increased average daily gain (ADG; P = 0.02) and gain to feed ratio (G:F) by approximately 12%. Cattle fed the 2X diet tended to have 6.5% greater ribeye area (P = 0.09), but similar USDA yield grade, backfat thickness, and dressing percentage (P ≥ 0.34) when compared with cattle fed the 1X diet. Daily CO2 and CH4 emissions, daily O2 consumption, CH4 yield, and respiratory quotient were unaffected by treatment (P ≥ 0.47). The improvement in ADG resulted in a tendency for CH4 emission intensity to be decreased by 9.1% (P = 0.09) when the concentration of limestone was 2.6% of dietary DM. While increasing dietary limestone concentration from 1.3 to 2.6% of diet DM did not influence absolute daily CH4 emissions, it increased ADG through an improvement in feed efficiency, which translated to a tendency for a reduction in CH4 emission intensity. These preliminary data suggest that there may be a benefit to feeding limestone or calcium at levels greater than currently recommended by the NASEM (2016). Future research should focus on determining optimum dietary limestone or calcium levels for finishing cattle.

240 Comparing Increasing Tryptophan: Lysine Ratios in Distiller Dried Grains-Based Diets with or without Distiller Dried Grains withdrawal Strategy on Growth and Carcass Performance of Grow-Finish Pigs

Abstract A total of 6,240 pigs [DNA 600 × PIC 1050; initial body weight (BW) = 22.5 ± 0.20 kg], divided into 2 groups, were used in 119- or 120- day study comparing increasing Trp:Lys ratio in diets with DDGS or a DDGS withdrawal strategy on growth and carcass performance and carcass fat iodine value of grow-finish pigs. Pigs were randomly allotted to 1 of 7 dietary treatments with 30 to 36 pigs per pen and 26 replications per treatment. Diets were fed in 4 phases (approximately 23 to 44, 44 to 71, 71 to 104, and 104 kg to market). Diets included a control corn-soybean meal-based diet formulated to a 19% SID Trp:Lys ratio, 4 diets with 30% DDGS fed in all four phases and formulated to achieve 16%, 19%, 22%, or 25% SID Trp:Lys ratio, respectively, and 2 DDGS withdrawal strategy diets: 19% SID Trp:Lys with 30% DDGS in phase 1 through 3 and then in phase 4, 0% DDGS with either a 19 or 25% Trp:Lys ratio. Overall, BW, ADG, ADFI, and G:F increased (linear, P < 0.05) as SID Trp:Lys ratio increased in diets with 30% DDGS fed in all 4 phases (Table). Pigs fed diets containing a SID Trp:Lys ratio of 19% and 30% DDGS from phases 1 through 3 and 0% DDGS in phase 4 had the greatest numeric ADG and ADFI for the overall study, but was not different than pigs fed the control for ADG, or the 25% Trp:Lys withdrawal treatment and the 30% DDGS diets with 25% Trp:Lys ratio throughout the study for ADG and ADFI. Hot carcass weight and carcass yield increased (quadratic, P < 0.05) as Trp:Lys ratio increased. Carcass fat samples were taken from the loin-butt junction and analyzed for iodine value. Pigs fed the control diet had decreased (P < 0.05) carcass fat iodine value compared with pigs fed DDGS throughout the study, with pigs fed the two DDGS withdrawal strategies having decreased (P < 0.05) iodine values compared with pigs fed 30% DDGS in all 4 phases. In summary, increasing the SID Trp:Lys ratio in diets with 30% DDGS resulted in a linear improvement in ADG, ADFI, G:F, and BW but did not influence iodine values. Removing DDGS from the diet in the last period reduced carcass fat iodine value and increased growth rate during the withdrawal period compared with pigs fed 30% DDGS throughout, indicating value in a DDGS withdrawal strategy.

PSV-7 Evaluation of Narasin Inclusion Level on Growth Performance and Carcass Characteristics of Growing-Finishing Pigs

Abstract Previous studies evaluating 15 mg/kg of narasin have shown improvements in BW, ADG, and G:F. However, FDA approved labeling for narasin indicates improved G:F with increased inclusion levels (20 to 30 mg/kg), which may provide greater economic return with higher feed costs. Some commercial systems have shown improvements in ADG and G:F when feeding 20 or 30 mg/kg narasin compared with 15 mg/kg. As such, two studies were conducted to evaluate 30 mg/kg of narasin on growth performance and carcass characteristics of growing-finishing pigs. Studies were carried out using a randomized complete block design with three narasin levels: 0, 15, or 30 mg/kg. Study 1 (2,545 pigs) was carried out from 42.6 ± 1.3 kg to 132.9 ± 3.6 kg. Study 2 (1,235 pigs) was carried out over a fixed time of 112 days from 39.1 ± 3.0 kg to 139.8 ± 3.5 kg. All pigs were fed diets that met or exceeded nutrient recommendations of growing-finishing pigs (NRC, 2012). Pigs were offered ad libitum access to feed and water throughout the study and weighed every 28 days and at every marketing event. Feed additions and feed remaining in the feeder at the time of pig weighing was recorded. Due to relatively low carcass recovery at the harvest facility, carcass data for Study 1 are not presented. Feeding 30 mg/kg of narasin did not improve (P > 0.05) growth or carcass performance compared with feeding 15 mg/kg narasin (Table 1). Compared with controls, feeding 15 mg/kg narasin increased final body weight (1.3 kg and 1.5 kg for Study 1 and 2, respectively), increased hot carcass weight (1.9 kg – Study 2), and improved carcass yield (0.4 percentage units), although differences were not always statistically different (P > 0.05). Overall G:F was improved 1.5% (P < 0.05) in Study 1, but not different (P > 0.05) than controls in Study 2. Results of this study confirm improvements in growth performance and carcass characteristics from feeding 15 mg/kg narasin to growing-finishing pigs. The outcomes of feeding 30 mg/kg of narasin were unexpected based on field outcomes and warrant further research.

120 Evaluation of Anchovy Fish Meal and Fish Solubles Compared with Other Specialty Protein Sources on Nursery Pig Performance

Abstract A total of 330 pigs (DNA 600 × 241, initially 4.9 ± 0.2 kg, 19 d old) were used to evaluate anchovy fish meal and fish solubles compared with other specialty protein sources on nursery pig growth performance and fecal dry matter (DM). At weaning, pigs were allotted to 1 of 6 dietary treatments with 4 or 5 pigs per pen and 12 replications per treatment in a completely randomized design. Dietary treatments consisted of different protein sources added based on relative SID Lys content and included: 1) enzymatically treated soybean meal (ESBM, HP 300, Hamlet Protein, Findlay, OH) at 7.0% of the diet; 2) spray-dried bovine plasma (SDBP, APC Corp, Ankeny, IA) at 3.5% of the diet; 3) fermented soybean meal (ME-PRO, Prairie Aquatech, Brookings, SD) at 5.0% of the diet; 4) fermented soybean meal enriched with 6.5% fish solubles (TASA, Lima, Peru) at 5.21% of the diet; 5) fish meal (TASA Prime meal, TASA, Lima, Peru) at 4.85% of the diet; and 6) fish meal enriched with 6.5% fish solubles (TASA Swine, TASA, Lima, Peru) at 5.05% of the diet. All diets contained the same conventional soybean meal level within phase. Treatment diets were fed in 2 phases, d 0 to 12 and d 12 to 25, for phase 1 and 2, respectively. Following phase 2, all pigs were fed a common diet for an additional 15 d. Although there was a 5 to 7% improvement in ADG for pigs fed spray-dried bovine plasma and fish meal with solubles, there were no significant differences in growth performance (P > 0.10) between treatments for any period or overall (Table). There was a treatment × day interaction (P = 0.003) for fecal dry matter largely driven by the increase in fecal DM for pigs fed spray-dried bovine plasma from d 12 to 25. On d 12, there were no differences between treatments for fecal DM (P > 0.10); however, on d 25, pigs fed spray-dried bovine plasma had improved (P = 0.017) fecal DM compared with pigs fed enzymatically treated soybean meal with all other treatments intermediate. In summary, anchovy fish meal with or without fish solubles can be utilized in nursery pig diets without decreasing growth performance.

171 Effects of a Dietary Immuno-Modulator on Growth Performance in Nursery Pigs

Abstract Feed-grade antibiotics in pig production were used to not only treat and prevent disease, but to promote growth as well, with improvements in ADG of up to 16% and F:G of up to 6% in nursery pigs common. However, these uses may contribute to antibiotic-resistant microbes that negatively affect human and animal health, and the swine industry seeks alternatives. OmniGen-AF (Phibro Animal Health, Teaneck, NJ; OG), a blend of vitamins, minerals, and microbial ingredients is a dietary immuno-modulator used to support immune function and reduce the negative effects of stressors in dairy cattle. Weaning is inherently stressful to pigs. There are limited data, however, on the effects of OG on growth and well-being in swine. The objective was to determine the effect of dietary supplementation with OG on growth performance in 21-day-old weaned pigs. Barrows (n = 36) and gilts (n = 36) were blocked by weight, and placed in sex-specific pens of three pigs each. Within blocks, pens were assigned to ad libitum access to OG (4 g/45.4 kg∙BW-1ּּּ ∙day-1) or control diets in a 2 x 2 factorial arrangement. The factors consisted of sex and presence or absence of OG in the diets of a three-phase feeding regimen. There were 6 replicate pens per sex and dietary treatment combination. Compared with gilts, barrows were heavier (effect of sex, P < 0.01), and across diets pigs showed an increase in BW during the 42-d trial (effect of day, P < 0.01). There were no effects (P > 0.10) of diet, or diet by sex on growth performance (ADG, 0.86 vs. 0.84 kg, SE = 0.05; ADFI, 1.42 vs. 1.41 kg, SE = 0.07; and, F:G, 1.66 vs. 1.69, SE = 0.03, for OG and CON, respectively). Fecal consistency scores (1 to 5; 1 = exceptionally firm, 5 = very loose and watery) were affected by day (P < 0.01), increasing (P = 0.02) from day 0 (3.00 ± 0.07) to a peak on day 4 (3.29 ± 0.07), before decreasing to values on d 35 (3.00 ± 0.07) and 42 (3.00 ± 0.07) that were not different from values on day 0. There were no effects (P > 0.32) of diet or sex on scores. No pig deaths occurred during the experiment. In this study, dietary supplementation with OG did not affect growth performance in pigs. The experiment, however, was conducted in a clean, highly managed University facility, and overall pig health appeared excellent as indicated by daily observations, fecal consistency scores, and no mortality occurring during the study. In this situation, it would be difficult to show a positive effect of a feed additive because the pigs were perhaps already performing at or near their genetic potential.

Effects of coated folic acid and coated methionine on growth performance, nutrient digestibility and rumen fermentation in Simmental bulls

In one-carbon metabolism, methionine (Met) is methyl donor and folic acid (FA) is responsible for the transfer of methyl groups. Approximately 25 % of coated methionine (CMet) and coated folic acid (CFA) released in the rumen at 24 h of incubation. Therefore, the present study investigated the effects of CMet or/and CFA on growth performance, nutrient digestibility and rumen fermentation in bulls. Forty Simmental bulls, 464 ± 15.9 kg of body weight (BW), were blocked by BW and randomly assigned to four groups in a 2 × 2 factorial arrangement of treatment, with factors being CFA 0 or 6 mg FA/kg dietary dry matter (DM) and CMet 0 or 0.66 g Met/kg dietary DM. The experiment period was 81 days long with 20 days for adaptation and 61 days for data and sample collection. Dry matter intake increased (P = 0.001) with CFA or CMet addition. The CFA × CMet interaction was noticed on average daily gain (ADG; P = 0.001) and feed conversion ratio (FCR; P = 0.020); the improvements in ADG and FCR were greater for supplementing CMet in diets with CFA than in diets without CFA. The digestibility of DM, organic matter, neutral detergent fiber and acid detergent fiber increased (P < 0.050) with CFA or CMet addition. When CMet was supplemented, crude protein digestibility increased in CFA diets and was unchanged in diets without CFA. Ruminal pH decreased (P < 0.050), but total volatile fatty acid concentration increased (P < 0.050) with CFA or CMet addition. Acetate to propionate ratio was unchanged with CFA addition, but decreased (P = 0.039) with CMet addition. Rumen ammonia-N concentration decreased (P < 0.050) for either CFA or CMet addition. The activities of carboxymethyl cellulase, protease, α-amylase and cellobiase and populations of protozoa, total bacteria, fungi, dominant cellulolytic bacteria, Ruminobacter amylophilus and Butyrivibrio fibrisolvens increased (P < 0.050) with CFA or CMet supplementation. The CFA × CMet interaction was noticed on Ruminococcus albus population (P = 0.014); when CMet was supplemented, R. albus population increased for diets without CFA and was unchanged for diets with CFA. The activities of chymotrypsin in duodenum increased (P < 0.050) with CFA or CMet supplementation, and that of amylopsin and trypsin in ileum increased (P < 0.050) for bulls receiving CFA addition. The concentrations of glucose, albumin and urea nitrogen in blood were unchanged and homocysteine decreased (P < 0.050) with CFA or CMet supplementation. The CFA × CMet interaction was noticed on blood total protein concentration (P = 0.045); when CMet was added, blood total protein concentration increased for diets without CFA and was unchanged for diets with CFA. The concentration of folate in blood increased (P = 0.001) for CFA addition. The concentration of Met increased (P = 0.002) for CMet supplementation. The results indicated that dietary CFA or/and CMet supplementation improved growth performance, nutrient digestibility and rumen fermentation, and the greatest daily gain was observed for combined addition of CFA and CMet in bulls.

A second iron injection administered to piglets during lactation improves hemoglobin concentration, growth performance, and carcass characteristics at slaughter.

An experiment was conducted to evaluate the effects of a second injection of iron dextran administered on days 6 to 8 of age. A total of 144 crossbred pigs (equal barrows and gilts; initial age 6 to 8 d; initial body weight [BW] = 2.86 ± 0.01 kg) were assigned to either the control (CON) or an added-injection treatment (+Fe). Pigs were paired by sex and BW within a litter and randomly assigned to the iron treatment within each pair. All pigs had received an initial intramuscular (IM) injection of iron dextran (200 mg Fe) <24 h after birth. Pigs assigned to the +Fe treatment received a second IM injection of iron dextran (200 mg Fe) on days 6 to 8. All pigs were weaned at 22 to 25 d, housed 6 pigs/pen, and received a common corn-soybean meal diet. BW and feed disappearance were recorded every 2 wk. Hemoglobin (Hb) concentrations were measured at birth, initiation of experiment (days 6 to 8), weaning, and the end of the nursery and end of the study. At the end of the study, 1 pig/pen (n = 12 pigs/treatment), closest to the pen mean was selected and slaughtered for carcass characteristic measures. The individual pig served as the experimental unit for BW, Hb, average daily gain (ADG), and carcass characteristic data whereas the pen served as the experimental unit for average daily feed intake, and gain/feed ratio data. The +Fe pigs had a greater Hb at weaning (13.1 vs. 10.7 g/dL, respectively; P < 0.01) and end of the nursery (12.1 vs. 11.7 g/dL, respectively; P = 0.01) compared to CON pigs. During the finisher period, +Fe pigs had a greater ADG (0.94 vs. 0.91 kg, respectively; P = 0.05) compared to CON pigs. Overall, pigs receiving the second iron injection had an ~4% increase in ADG (P = 0.04) from weaning to the end of study. The cumulative improvement in ADG from weaning to the end of study observed for +Fe group resulted in +Fe pigs having a heavier BW at the end of the study (~3 kg; P = 0.04). Following slaughter, +Fe pigs had ~7.2% heavier trimmed loin (P = 0.04) compared to the CON pigs. In conclusion, administering a second iron injection resulted in greater Hb at weaning and the end of the nursery as well as improved growth performance from weaning to the end of study weight and increased carcass weight at slaughter.

Influence of Protein Source on Growth Performance in Nursery Pigs

A total of 330 pigs (241 × 600, DNA; initially 10.7 lb) were used to determine the influence of dietary protein source on growth performance in nursery pigs. At weaning, pigs were randomly allotted to 1 of 6 dietary treatments with 4 or 5 pigs per pen and 12 replications per treatment. Dietary treatments were arranged in a one-way treatment structure with diets containing different protein sources; enzymatically treated soybean meal (HP 300; Hamlet Protein, Findlay, OH), spray-dried bovine plasma (APC Corp, Ankeny, IA), fermented soybean meal (ME-PRO; Prairie Aquatech, Brookings, SD) with or without fish solubles (TASA, Lima, Peru), fish meal (TASA Prime meal; TASA, Lima, Peru), and custom-made fish meal (TASA Swine; TASA, Lima, Peru). Because of a delay in arrival of the fish meal source, all pigs were placed on a common phase 1 diet for 3 d after weaning. On d 3, all feeders were weighed, dumped, and refilled with experimental diets. Pigs were fed experimental phase 1 diets for 9 d (d 3 to 12) followed by phase 2 diets for 15 d. Following phase 2, all pigs were fed a common diet for an additional 15 d. In all weigh periods and overall, there were no significant differences between treatments for BW, ADG, ADFI, and F/G. For economic analysis (d 0 to 40), pigs fed spray-dried bovine plasma had the greatest (P ≤ 0.001) feed cost and feed cost per lb of gain compared to all other treatments. There were no differences in revenue or IOFC between treatments. In summary, utilizing alternative protein sources in phase 1 and 2 nursery pigs’ diets had no effect on growth performance. However, there was a 5 to 7% improvement in ADG for pigs fed spray-dried bovine plasma and custom-made fish meal.

Comparing Increasing Tryptophan:Lysine Ratios in DDGS-Based Diets with or without a DDGS Withdrawal Strategy on Growth Performance and Iodine Value of Growing-Finishing Pigs

A total of 6,240 pigs (DNA 600 × PIC 1050; initially 49.7 × 2.23 lb), divided into 2 groups, were used in a 119- or 120-d study to compare increasing the Trp:Lys ratio in diets with DDGS or a DDGS withdrawal strategy on growth performance and carcass fat iodine value of grow-finish pigs. Pigs were randomly allotted to 1 of 7 dietary treatments with 30 to 36 pigs per pen and 26 replications per treatment. Diets were fed in 4 phases (approximately 50 to 96, 96 to 157, 157 to 220, and 220 lb to market). Diets included a control corn-soybean meal-based diet formulated to a 19% SID Trp:Lys ratio; 4 diets with 30% DDGS fed in all four phases and formulated to achieve a 16%, 19%, 22%, or 25% SID Trp:Lys ratio, respectively; and 2 DDGS withdrawal strategy diets: 19% SID Trp:Lys with 30% DDGS in phases 1 through 3 and then 0% DDGS in phase 4 with either a 19 or 25% Trp:Lys ratio. Overall, BW, ADG, ADFI, and F/G improved (linear, P < 0.05) as the SID Trp:Lys ratio increased in diets with 30% DDGS fed in all 4 phases. Hot carcass weight and carcass yield increased (quadratic, P < 0.05) as the Trp:Lys ratio increased along with backfat depth (linear, P = 0.040). Pigs fed diets containing a SID Trp:Lys ratio of 19% and 30% DDGS from phases 1 through 3 and 0% DDGS in phase 4 had the greatest numeric ADG and ADFI for the overall study, but were not different than pigs fed the control, the 25% Trp:Lys withdrawal treatment, or the 30% DDGS diets with 25% Trp:Lys ratio throughout the study. Pigs fed the control diet had decreased (P < 0.05) carcass fat iodine value compared to pigs fed DDGS throughout the study, with pigs fed the two DDGS withdrawal strategies having lower (P < 0.05) iodine values compared to pigs fed 30% DDGS in all 4 phases. No significant differences (P > 0.05) in revenue per pen or IOFC per pen were observed, however, feed cost per lb of gain (quadratic, P = 0.001) and feed cost per pig placed (linear, P = 0.002) increased and revenue per pig placed tended to increase (P = 0.064) as the Trp:Lys ratio increased. In summary, increasing the SID Trp:Lys ratio in diets with 30% DDGS resulted in a linear improvement in ADG, ADFI, F/G, and BW but did not influence iodine values. Removing DDGS from the diet in the last period reduced carcass fat iodine value and increased growth rate during the withdrawal period compared to pigs fed 30% DDGS throughout, indicating value in a withdrawal strategy.

PSVI-5 Effect of apple and anise flavour supplementation on growth performance, nutrient digestibility, blood profiles and carcass quality in growing-finishing pigs

Abstract The present study was undertaken to determine the effects of different flavours (apple and anise) on growth performance, nutrient digestibility, blood profiles and carcass quality in growing-finishing pigs. A total of 96 pigs [(Landrace × Yorkshire) × Duroc] with an average initial BW of 28.2 ± 0.7 kg were assigned to 1 of 3 dietary treatments. The treatments consisted of (1) CON, basal diet; (2) APF, basal diet + 0.05% apple flavour; (3) ANF, basal diet + 0.05% anise flavour. There were 8 replications (pens) per treatment and 4 pigs per pen (2 barrows and 2 gilts). The flavour was added at the expense of corn (0.05%). The experiment lasted for 15 wks. The data were analyzed by ANOVA using the GLM procedure of SAS (SAS Institute Inc., Cary, NC, USA) with the pen as the experimental unit. Variability in the data was expressed as the standard error of means (SEM) and a probability level of p &amp;lt; 0.05 was considered to be statistically significant. During week 0-5, pigs fed ANF diets had greater (p &amp;lt; 0.05) ADG and ADFI than those fed CON and APF diets. Dietary ANF treatment increased (p &amp;lt; 0.05) ADG during 0-15 week compared with CON treatment (Table 1). At the end of 5 week, the apparent total tract digestibility of nitrogen in ANF treatment was improved (p &amp;lt; 0.05) compared with that in CON treatment (Table 1). There were no differences (p &amp;gt; 0.05) in the red blood cell and white blood cell counts or lymphocyte percentage among treatments. In conclusion, anise flavour supplementation could lead to significant improvement in ADG and N digestibility in growing pigs and the ADG was also higher in finishing pigs fed anise flavour supplemented diet. Furthermore, apple flavour supplementation had minor effect on growth performance, nutrient digestibility, blood profiles or carcass quality in finishing pigs.

Effects of methylsulfonylmethane and neutralizing anti–IL-10 antibody supplementation during a mild Eimeria challenge infection in broiler chickens

A 28-day experiment was conducted in broilers to study the effects of feeding methylsulfonylmethane (MSM) and IL-10–neutralizing antibody from dried egg product (DEP) on the growth performance, immune responsivity, oxidative stress parameters, and gut health outcomes during a mild infection with mixed species of Eimeria. A total of 500 male Ross 308 chicks were allocated to five treatments: sham-inoculated (uninfected) chickens fed control diet (UCON), Eimeria-infected chickens fed control diet (ICON), and Eimeria-infected chickens fed control diet supplemented with 287 U/tonne of DEP (I-DEP), 0.4% MSM, or their combination (I-DEP-MSM), with 10 replicate cages of 10 birds per treatment. All infected groups received 1 mL of an oral inoculum containing Eimeria acervulina (10,000 oocysts), Eimeria maxima (5,000 oocysts), and Eimeria tenella (5,000 oocysts) on study days 7 and 14. Data were analyzed as a two-way ANOVA for all treatments including Eimeria-infected groups, in addition to a single degree of freedom contrast to compare uninfected and infected groups receiving the control diet. Mild Eimeria infection did not influence the growth performance in ICON compared with UCON at any time points. Overall (day 0–28) growth performance parameters were not influenced by either infection or dietary supplementation of MSM or DEP. However, birds in I-DEP-MSM showed improved ADG during study day 7 to 14 (i.e., 7 d after primary inoculation) indicating a beneficial effect immediately after Eimeria infection. Although MSM supplementation reduced thiobarbituric acid reactive substances (day 21 and 28), both MSM and DEP improved the total antioxidant capacity (day 21) in the plasma of infected birds. Histopathological outcomes were not influenced by treatments, and fecal oocyst output was higher in MSM- and DEP-supplemented groups than with ICON, indicating no beneficial effects. Similarly, expression of cecal inflammatory cytokines (IL-10, IL-1β, and interferon-γ) was not affected by MSM, DEP, or their combination. Overall, the current results suggest that both MSM and DEP supplementation may benefit birds during a mild Eimeria infection as indicated by improvements in ADG and oxidative stress outcomes.

145 Effects of titrated levels of water soluble zinc amino acid complex on growth performance of nursery pigs

Abstract Previously, we reported that supplementing a water soluble zinc via drinking water (0 to 80 mg/L) to nursery pigs improved ADG and G:F. To evaluate the efficacy of higher titrated levels of this water soluble zinc amino acid complex (ProPath®Zn LQ, Zinpro Corporation, Eden Prairie, MN) on growth performance, 280 crossbred pigs (5.5 kg BW; 19 d of age) were randomly allotted to four water treatments (7 pens/treatment; 10 pigs/pen). The water treatments were 0, 40, 80 and 160 mg Zn/L of water. Pigs were fed in 4 dietary phases with complex, nutrient-dense, corn-soybean meal-based diets: Phase 1 and 2 (2,500 and 1,750 mg Zn as ZnO/kg; d 1–7 and 7–14, respectively) and Phase 3 and 4 (200 mg Cu as CuSO4/kg; d 14–23 and 23–42, respectively). Pigs and feeders were weighed weekly to determine ADG, ADFI, and G:F. Water meters were used to record and calculate water disappearance and zinc intake. Data were analyzed as a randomized complete block design. Orthogonal polynomial contrasts were used to determine linear and curvilinear effects. Water and total zinc intake increased linearly (P &lt; 0.001) with increasing water zinc concentration. From d 0–14 when high dietary zinc was fed, there were no differences (P &gt; 0.10) in ADG, ADFI, or G:F. However, from d 14–42 when basal levels of zinc were fed, quadratic improvements in ADG (0.545, 0.561, 0.578, 0.546 kg; P &lt; 0.05) and G:F (0.686, 0.706, 0.723, 0.702; P &lt; 0.01) were observed with increasing zinc via water. Similarly for d 0–42, ADG (0.435, 0.440, 0.454; 0.434 kg; P = 0.07), G:F (0.726, 0.740, 0.763, 0.749; P = 0.05) and average ending wt (23.73, 23.97, 24.55, 23.70 kg; P = 0.07) improved quadratically with increasing zinc. In conclusion, supplementing ProPath®Zn LQ via water resulted in improvements in ADG and G:F for nursery pigs.

134 Evaluation of a medium chain fatty acid-based feed additive for nursery pigs

Abstract A total of 350 pigs (DNA 400×200, initial BW=6.3 kg) were used in a 34-d growth trial to evaluate the effects of a medium chain fatty acid (MCFA)-based feed additive in nursery pig diets. Following arrival to the nursery facility, pigs were randomized to pens (5 pigs per pen) and allowed a 4-d acclimation period. Thereafter, pens of pigs were blocked by BW and randomized to 1 of 5 dietary treatments (14 pens per treatment). Treatments were a dose response of 0, 0.5, 1.0, or 2.0% MCFA-based additive (CaptiSURE, Kemin Industries, Inc.; Des Moines, IA) as well as a treatment including 1.0% MCFA from a 1:1:1 blend of C6, C8, and C10 (Sigma Aldrich, St. Louis, MO). Treatment diets were formulated and manufactured in two dietary phases (d 0 to 13 and 13 to 34). Data were analyzed as a randomized complete block design with pen serving as the experimental unit. Overall (d 0 to 34), increasing CaptiSURE increased (linear, P ≤ 0.014) ADG and ADFI. Feed efficiency improved (quadratic, P = 0.002) with increasing CaptiSURE up to 1% of the diet with no benefit thereafter. As a result of the linear improvement in ADG, pigs fed 2.0% CaptiSURE were 1.8 kg heavier (P = 0.05) than pigs fed diets without MCFA at d 34. There was no evidence for differences between pigs fed 1.0% CaptiSURE and pigs fed the 1.0% MCFA blend of C6, C8, and C10 in phase 1, phase 2 or in overall performance. In summary, the addition of up to 2% of this MCFA-based additive in nursery pig diets resulted in linear improvements in ADG and ADFI. The MCFA-based feed additive also resulted in a similar improvement in growth performance as the C6, C8, and C10 MCFA blend when both were added at 1% of the diet.

Benefit-cost analysis to estimate the payback time and the economic value of two Mycoplasma hyopneumoniae elimination methods in breeding herds

Mycoplasma hyopneumoniae (Mhyo) is generally accepted to be the most common porcine respiratory pathogen worldwide causing big economical losses in swine production by affecting pig’s downstream performance. The objective of this study was to develop a partial budget model to determine the payback period and economic value of two Mhyo elimination protocols. Retrospective data recorded from 2004 to 2017 from 70 breeding herds that implemented herd closure or whole-herd medication protocol targeting Mhyo elimination. Close out data was used to estimate differences in downstream performance between Mhyo-negative and positive flows. Assuming a 5000 sows breed-to-finish operation producing 135,870 weaned pigs and 125,000 finishing pigs/year, the total cost for implementing Mhyo elimination was $112,100 using the herd closure protocol, and $185,700 for the medication protocol. Statistically differences (p < 0.05) in downstream performance were observed for ADG and mortality, but not for feed conversion rate. The parameters that accounts for the greatest benefits were related to the improvement in ADG, savings in antibiotic medication in growing pigs and improvement in feed conversion rate. The benefit of Mhyo elimination was $877,375 per farm per year, or $7.00 per pig marketed. The estimated project value after 1 year was $616,121 for the herd closure considering a probability of success of 83%, and $323,177 for the medication protocol for 58% chance of success. The project value reached the break-even point when the cost per sow was $145.64 for the herd closure and $101.78 for the medication protocol. The payback period was 2 months after the start of marketing Mhyo-negative pigs for the herd closure, and 7 months for the medication protocol adjusted for the probability of success for each protocol. The protocols described here can be easily applied with a good success rate and showing that the benefits obtained are greater than the costs of project failure. Even if the farm stayed negative only a year, the economic benefits downstream are worth the investment. This information may help producers and veterinarians on decision-making process to conduct a Mhyo elimination protocol in their herds.

Evaluation of a partially de-oiled microalgae product in nursery pig diets.

Although microalgae can be used as a source of energy and macronutrients in pig diets, there is limited information on the use of partially de-oiled microalgae coproducts in swine feeding programs. The objectives of this study were to evaluate the effects of a partially de-oiled microalgae extract (MAE) in nursery pig diets on growth performance and health status. A total of 300 pigs (initial BW = 6.3 ± 2.1 kg) were used in a 42-d experiment. Treatments included a standard corn-soybean meal control diet, and diets containing 1, 5, 10, or 20% MAE replacing primarily corn. The ME content of MAE was calculated from the chemical composition, and diets were formulated to meet or exceed nutrient requirements for nursery pigs. Pigs were stratified by weaning BW into 12 blocks in a randomized complete block design, with sex distributed evenly among blocks. Pens of pigs (5 pigs/pen) were assigned randomly within block to one of five dietary treatments. Pig BW and feed disappearance were recorded weekly. On day 42, 30 pigs were harvested and sections of the jejunum and ileum were collected for gut morphology analysis, and a liver sample was collected for metabolomic analysis using liquid chromatography-mass spectroscopy. Data were analyzed by ANOVA with diet as treatment effect, and contrasts were used to test linear or quadratic effects of dietary MAE inclusion level. Overall, pigs fed 1% and 5% MAE had the greatest (quadratic P < 0.05) ADG, resulting from greater (quadratic P < 0.05) ADFI. There was a tendency for a greater number of pigs requiring injectable treatments (P = 0.16) and a greater mortality (P = 0.14) in pigs fed the control diet than pigs in any of the diets with the MAE. Final BW increased (P < 0.05) for pigs fed 1% and 5% MAE diets. The improvements in ADG were not explained by differences in mucosa height or goblet cell count among dietary treatments. Pigs fed diets containing 1% or 5% MAE had relatively less concentration (P < 0.05) of ammonia in the liver and had changes in metabolites associated with the urea cycle. In conclusion, feeding MAE resulted in increased growth responses and may have beneficial health effects when fed to nursery pigs.

Evaluating the effects of fish meal source and level on growth performance of nursery pigs.

Three experiments were conducted to determine the effects of fish meal source on nursery pig growth performance. In experiment 1, 250 pigs (PIC 327 × 1,050, initially 7.1 ± 1.00 kg) were fed either a corn-soybean meal-based diet, a diet containing 8.3% enzymatically treated soybean meal (HP 300, Hamlet Protein, Findlay, OH), or diets containing 6% fish meal from one of three sources (IPC 790, The Scoular Company, Minneapolis, MN; Special Select Menhaden, Omega Proteins, Houston, TX; LT Prime Menhaden, Daybrook Fisheries Inc., New Orleans, LA; source 1, 2, and 3, respectively). In a completely randomized design, there were five pigs per pen and 10 pens per treatment with diets fed for 13 d. There was no evidence for differences in ADG or ADFI among pigs fed the three fish meal sources; however, pigs fed source 1 had marginally decreased (P = 0.068) G:F compared with pigs fed diets with other protein sources. In experiment 2, 350 barrows (DNA Line 200 × 400; initially 6.5 ± 0.90 kg) were assigned to one of seven dietary treatments including the same control diet and diets containing the three fish meal sources used in experiment 1, but fed at 3% or 6%. There were five pigs per pen and 10 pens per treatment with diets fed for 14 d. A source × level interaction (linear, P < 0.05) for ADG and G:F was observed. Increasing fish meal source 1 increased ADG and G:F; however, pigs fed source 2 had improved ADG and G:F at 3%, but decreased performance at 6% compared with control pigs. Pigs fed source 3 had no further improvements in ADG or G:F beyond the 3% inclusion. Fishmeal analysis for total volatile N, and modified Torry digestibility did not appear to correspond with any growth performance differences measured in experiments 1 or 2. In experiment 3, 700 barrows (DNA Line 200 × 400, initially 6.5 ± 0.84 kg) were fed a control diet or four diets with 6% fish meal (source 3) containing either 0.87%, 8.70%, 16.52%, or 24.35% fish solubles. There were five pigs per pen and 28 pens per treatment with diets fed for 21 d. Overall, pigs fed diets with fish meal had increased (P < 0.05) ADG and ADFI compared with pigs fed the control diet. There was no evidence for differences in growth performance as fish solubles increased. In conclusion, inconsistencies were observed in growth responses to different fish meal sources, but the amount of fish solubles, total volatile N, or modified Torry digestibility of fishmeal does not appear to explain these differences.

Effect of castration method and analgesia on inflammation, behavior, growth performance, and carcass traits in feedlot cattle.

Our objective was to determine the effect of castration timing, method, and use of the analgesic meloxicam (MEL) on inflammation, behavior, performance, and carcass traits in feedlot cattle. This study was a randomized complete block design conducted over a 3-yr period. In total, 194 crossbred beef calves from a single ranch origin were randomized at birth to receive one of five treatments arranged as a 2 × 2 + 1 factorial: 1) bulls castrated within 48 h of birth (CON), 2) bulls surgically castrated on day 0 without MEL (SUR), 3) bulls surgically castrated on day 0 with MEL (SUR + MEL), 4) bulls band castrated on d 0 without MEL (BAN), and 5) bulls band castrated on day 0 with MEL (BAN + MEL). Upon feedlot arrival (day -11; average 287 ± 2.03 d of age), animals were blocked by initial BW (224 ± 4.5 kg) and assigned randomly to treatment pens in three consecutive years (n = 2 pens per treatment in each year). Oral MEL was administered at 1 mg/kg BW concurrent with applicable castration treatment on day 0. Data were analyzed using the MIXED and GLIMMIX procedures of SAS with pen (year) serving as experimental unit. From days 0 to 7, ADG was reduced (P = 0.01) for surgical (-0.42) compared to band (0.43 kg/d) castration. Conversely, ADG was increased for surgical (1.74) vs. band (1.46 kg/d) castration from days 14 to 32. There was also an overall (day 0 to final) improvement in ADG for MEL (P = 0.02), but no effect of castration method was observed (P = 0.81). The CON group had the greatest (P = 0.05) marbling score. Backfat thickness was increased (P = 0.01) for MEL. A treatment × day interaction (P = 0.04) existed for serum haptoglobin, with SUR having the greatest (P < 0.01) concentration on days 1 and 4. Meloxicam administered in the surgically castrated treatment reduced (P = 0.01) serum haptoglobin concentration on day 1. Relative to baseline, standing duration for surgical castration was increased 113 min (P < 0.01), while banding caused 6.7 more lying bouts (P < 0.01) immediately following castration on day 0. Step count was greatest for BAN, intermediate for CON, and least for surgical (P < 0.01). Results suggest that MEL mitigated the more pronounced inflammation observed for surgical castration, whereas behavior was differentially altered for castration method indicative of a divergent pain response. Castration, regardless of method, transiently reduced ADG, but MEL administration improved overall ADG for both methods.

Influence of feeding enzymatically hydrolysed yeast cell wall + yeast culture on growth performance of calf-fed Holstein steers

ABSTRACTOne hundred and sixty-eight crossbred steers (133 ± 7 kg) were used in a 336-d experiment to evaluate the effects of enzymatically hydrolysed yeast cell wall plus yeast culture (EHY) supplementation on growth performance and carcass characteristics. Treatments consisted of steam-flaked corn-based diet supplemented with 0, 195, 390 or 585 mg/kg EHY. Supplemental EHY enhanced overall (336-d) dry matter intake (DMI, P < .01), averagde daily gain (ADG, P = .04), and final carcass weight (P = .04). Responses were maximal (quadratic effect, P ≤ .02) at the 195 mg/kg level of EHY supplementation. Feed intake enhancements were observed throughout each 112-d period of the study. Improvements in ADG were largely the result of increased DMI, as gain efficiency and estimated dietary net energy (NE) were not affected by EHY supplementation. Effects of supplemental EHY on other carcass measures were not appreciable (P > .20), except for a slight lowering (0.7%, P = .04) in carcass yield. We conclude that throughout the growing-finishing period, supplemental EHY will enhance ADG, resulting in marked increases in final carcass weight. This effect is due to consistent increases in DMI, as supplementation did not affect gain efficiency or estimated dietary NE.

250 Evaluation of bovine plasma in early nursery pig diets

Eight hundred and two barrows and gilts (5.48 ± 0.57 kg) were used to evaluate the use of bovine plasma in early nursery phases. Treatments included a bovine plasma ration (4% in phase 1 ration and 2% in phase 2 ration) and a negative control diet with no animal plasma protein. Pigs were started on experimental rations on the day of weaning (∼21 d of age) and arrival to the facility (d 0). A 3-phase nursery program was utilized, and diet changes occurred at 7, 20, and 39 d postwean. Pigs were penned in blocks of either 24 or 25 pigs/pen with a computerized feed system delivering feed to single-sided feeders. There were a total of 24 replications per treatment group. Treatment diets were fed until d 20, at which point all pigs were fed a common nursery 3 diet. Diets were formulated to meet or exceed nutrient requirements. Treatments were equalized across gender, and data were analyzed as a randomized complete block design using the PROC MIXED procedure of SAS with pen as the experimental unit and treatment as a fixed effect. There was a tendency for an improvement in ADG (P = 0.07) when pigs were fed plasma during the first 7 d. From d 7 to 20, ADG was significantly higher (P = 0.01) in pigs fed plasma. While G:F was not significantly different (P = 0.28), increased intake resulted in a heavier (P = 0.04) pig at d 20 when plasma was included in the diet. From d 20 to d 39, a common nursery diet was fed, and ADG and G:F were no longer significantly different based on treatment. Overall (d 0 to 39), there was a significant increase (P = 0.01 and 0.04, respectively) in ADG when pigs were fed plasma from d 0 to 20. Based on the results of this study, pigs that were fed plasma from d 0 to 20 have a higher ADG. Evaluation of bovine plasma in early nursery diets Evaluation of bovine plasma in early nursery diets

Comparative effect of direct-fed microbial regimen on health and performance of neonatal dairy heifer calves

This study was conducted to compare health and performance in neonatal dairy heifer calves supplemented with direct-fed microbial products in milk: (1) Propionibacterium freudenreichii NP24 and Lactobacillus acidophilus NP51 (BVM) or (2) Kluyveromyces m/f B0399 and Saccharomyces c/f 1026 (PBST). A total of 770 individually housed Holstein (n = 528), Jersey (n = 212), and crossbred (n = 30) heifers at a commercial calf-rearing facility were used for the primary group. Body weight was recorded on d 0 and 60 to determine ADG and percentage of daily BW gain, and health was monitored daily from arrival (d 0) through weaning (d 60). A subset group comprising 50 (n = 25 per treatment) Holstein (n = 32) and Jersey (n = 18) heifer calves were weighed periodically and analyzed separately to evaluate interim and overall performance and health. For both groups, heifers between 1 and 3 d of age were assigned randomly to treatment, and treatments were arranged within a single hutch row consisting of 100 heifers. A tendency (P = 0.09) for an improvement in ADG was observed for PBST heifers in the primary group. For the subset group, PBST had improved ADG from d 0 to 10 (0.29 vs. 0.05; P < 0.001), d 0 to 22 (0.31 vs. 0.23; P = 0.003), and overall (0.51 vs. 0.44 kg/d; P = 0.002). The percentage of daily BW gain was increased for PBST from d 0 to 10 (0.45 vs. 0.09%; P < 0.001) and overall (0.78 vs. 0.64%; P = 0.002). Also, PBST had a greater (P = 0.05) percentage of calves requiring a second respiratory disease treatment, but no other health differences were observed in this experiment. Results indicate PBST improved performance compared with BVM, but health was not clearly affected.