Abstract Over the last 20 years, the commercial sow has genetically changed in terms of body composition, increasing litter sizes and potential milk yield. These increases in litter size and milk yield have elevated metabolic demands during lactation leaving questions around if the existing nutrient requirement models represent the nutritional needs of the modern sow. Recent studies demonstrate greater requirements for energy, amino acids, and key micronutrients to support fetal growth, mammary development, colostrum composition, and lactation performance. Changes in sow housing and precision feeding technologies have added additional layers of practical approaches and estimation of nutrient requirements. While sow research has provided new insights into the lactating female, substantial knowledge gaps remain, and sow mortality continues to rise. As a result, traditional feeding paradigms may inadequately account for the metabolic demand placed on high-producing sows, which can result in reduced longevity, compromised reproductive efficiency, and variable piglet performance. As more feed grade amino acids have become available, research has allowed for a more refined set of requirements for branched chain amino acids and other amino acids such as histidine, as well as speculation on the inclusion level of feed grade lysine. In conclusion, refinement of sow nutrition must incorporate biological demand, dynamic modeling approaches, and multidisciplinary integration of physiology, environment, genetics, behavior, and precision management tools.

Abstract Compared to solvent-extracted soybean meal (SBM), extruded full-fat soybeans (FFSB) provide greater energy due to their higher oil content, while expeller soybean cake offers a moderate improvement in energy relative to SBM. Issues feeding pigs high levels of FFSB include increased antinutritional factors and altered dietary fatty acid composition, which could antagonize growth and alter carcass iodine value and meat quality. Compared to conventional soybeans, feeding high oleic acid soybeans (HO) may lower dietary polyunsaturated fat content and improve pig growth performance. The objective of this study was to evaluate the effect of feeding conventional or HO extruded whole soybeans on grow-finish pig performance and carcass characteristics. A total of 1260 pigs (27.8±1.11 kg BW; PIC 800 x1050) were weighed and randomly allotted by sex across 60 mixed-sex pens (21 pigs/pen). Pens were blocked by location in the barn and randomly assigned, within block, to one of four dietary treatments (15 pens/trt): 1) Conventional solvent-extracted SBM (CON), 2) Conventional FFSB (CFFSB), 3) High oleic acid FFSB (HOFFSB), and 4) High oleic acid soybean expeller cake (HOEC). Diets were fed in five phases (∼23-41, 42-63, 64-86, 87-109, and 110-133 kg BW) and were formulated to have similar SID Lys and SID Lys:ME. Pen BW and feed disappearance were collected at the start and end of each phase to calculate ADG, ADFI, and G:F. Pigs were marketed in multiple cuts at a target live BW of ∼130 kg. At a commercial harvesting facility, carcass weight, backfat depth, and loin depth were collected per pig, and carcass yield and fat-free lean were calculated. Additionally, carcass fat samples were collected for fatty acid analysis. All data were analyzed according to a randomized complete block design, with treatment and block included as fixed effects in the models. Pen was the experimental unit. Pen average pig BW and mortality and removals did not differ between treatments (P > 0.10). Overall, CON, CFFSB, HOFFSB, and HOEC ADG were not different (0.87, 0.89, 0.89 and 0.88 kg/d, respectively; P = 0.491). However, ADFI was higher in CON, compared to HOEC, CFFSB, and HOFFSB (2.37, 2.25, 2.16 and 2.17 kg/d, respectively; P < 0.001). Consequently, CFFSB and HOFFSB improved overall G:F compared to CON (111%) and HOEC (105%) treatments (P < 0.001). Carcass weight and loin depth did not differ across treatments. Feeding CFFSB or HOFFSB increased backfat by 8% compared to CON, with HOEC being intermediate (P = 0.004). Feeding CFFSB resulted in marginally reduced fat-free lean percent compared to CON and HOEC, while HOFFSB was intermediate. In conclusion, CFFSB and HOFFSB improved feed efficiency and increased backfat, with no impact on growth compared to CON. Furthermore, HOEC reduced pig ADFI and improved feed efficiency compared to CON.

The objective of this study was to determine the effect of increasing dietary soybean hull inclusion on diet digestibility, energy content, and nitrogen (N) balance in growing gilts. A 21-day study was conducted with two groups of 24 gilts with a starting body weight of 45.5 kg ±2.2 kg housed in individual metabolism stalls. Gilts were fed one of four dietary treatments containing either 0%, 10%, 20%, or 40% soybean hulls for a total of 12 gilts per treatment. The four diets were formulated to equal a standardized ileal digestibility (SID) lysine: metabolizable energy (Lys: ME) of 3.41. During the 21 days, gilts were evaluated over three collection periods. Each period consisted of four days of total fecal and urine collection. Gilts remained on their respective diets for the duration of the study. Urine, fecal, feed, and soybean hull samples were analyzed for N and gross energy concentration. Data were analyzed using SAS 9.4 using the GLIMMIX procedure, and gilt was the experimental unit. Results were considered significant if P ≤ 0.05. Feed intake was not different as soybean hull inclusion increased but increased across collection periods (P < 0.001). Apparent total tract digestibility (ATTD) of crude protein decreased linearly as soybean hull inclusion increased (P ≤ 0.001). Fecal N excretion increased as soybean hull inclusion increased (P ≤ 0.001) and over the three collection periods (P <0.001). Total urine N excretion increased over time and soybean hull inclusion caused a linear reduction in urinary N excretion (P ≤ 0.001). Nitrogen retention (g/d) was reduced by greater soybean hull inclusion (P = 0.028). Metabolizable energy (ME) decreased as soybean hulls inclusion increased in the diets (P ≤ 0.001). In conclusion, increasing soybean hulls up to 40% in the diet increased fecal N excretion and decreases urine N excretion and the ATTD of N. Additionally, the increase in soybean hulls in the diet decreased the ME value, while ME values increased as the time on the diet increased.

Abstract A total of 450 newly weaned pigs (PIC 800 x 1050, PIC, Hendersonville, TN) were used to evaluate the dietary SID Phe:Lys requirement in nursery pigs. Pigs were sorted into pens (5 barrows and 5 gilts each (10 pigs/pen)). Seven days after arrival pigs were blocked by body weight (5.73 ± 0.03 kg) and randomly assigned to one of six diets (0.330, 0.394, 0.458, 0.522, 0.586, 0.650 SID Phe:Lys). All pigs received a common medicated starter diet from day 0-7. Experimental diets were fed in two phases: 7-21 days and 21-28 days. Diets were isonitrogenous, isocaloric, and deficient in lysine (SID Lys 1.25 and 1.14%, respectively) with balanced dietary electrolytes. All other nutrients met or exceeded NRC (2012) dietary recommendations. Pen and feeder weights were recorded on day 7, 21, and 28 to calculate average daily gain (ADG), average daily feed intake (ADFI), and gain to feed (GF). Data were analyzed using polynomial contrasts based on equally spaced treatments in R (v4.4.1) with significance at P ≤ 0.05. Pen was the experimental unit, and block was treated as a fixed effect. Feeding SID Phe:Lys ratio of 0.65 maximized the ADG and GF during the trial period, while the SID Phe:Lys level of 0.586 maximized the overall ADFI. Similarly, on day 28 BW of pigs increased quadratically (P < 0.001) as SID Phe:Lys increased and the pigs with the greatest BW were fed a SID Phe:Lys ratio of 0.65. Breakpoint analysis was done with multiple model types; however, the broken line quadratic (BLQ) was used to estimate the requirement as it had the best fit based on the BIC value. The breakpoint for overall ADG was estimated to be 0.516 (95% CI [0.488, 0.544]). The overall ADFI breakpoint was estimated to be 0.534 (95% CI [0.496, 0.571]). The overall G:F breakpoint was estimated at 0.497 (95% CI [0.467, 0.528]). Based upon these data, the Phe:Lys requirement for nursery pigs is 0.516 for ADG, 0.534 for ADFI and 0.497 for G:F.

Forty-eight crossbred gilts (52.55 ± 4.12 kg) were used to evaluate the effect of high soybean meal (SBM) inclusion with dietary enzymes on growth and nutrient balance. Two sets of 24 gilts were placed in metabolism stalls and randomly assigned to one of six dietary treatments (8 pigs/trt). Experimental diets were fed in two, 12-d phases, urine and feces were collected for 72 h to assess nutrient digestibility and retention. Diets included: (i) negative control diet [NC, corn-soy (22% SBM) + synthetic AA], (ii) positive control diet, (PC, 41% SBM replacing synthetic lysine), (iii) PC + xylanase (WX), (iv) PC + multi-enzyme (VP, hemicellulase and pectinase), (v) PC + WX + VP (WXVP), and (vi) PC + 1500 FYT/kg phytase (SD). All but SD contained 600 FYT/kg phytase. Data were analyzed as repeated measures in SAS 9.4 (Statistical Analysis System, Cary, NC) with treatment, phase, and block as fixed effects and pig served as the experimental unit. Growth did not differ across treatments (P ≥ 0.13). Apparent total tract digestibility (ATTD) of DM and GE were unaffected (P ≥ 0.10), ash ATTD increased in high SBM diets (P < 0.01). Intake of nitrogen (N), phosphorus (P), calcium (Ca), and sulfur (S) increased with high SBM (HSBM) diets compared to NC (P < 0.01). Digestibility of nitrogen (N), phosphorus (P), and sulfur (S) increased in pigs fed HSBM diets (P < 0.01), while calcium (Ca) digestibility and retention were greatest in the PC and elevated phytase diets compared to the NC (P < 0.01). Absolute retention of N, P, and S was greater in higher SBM diets (P ≤ 0.02), though enzyme inclusion had minimal effects. Diet WX was intermediate with other HSBM treatments and NC for N retention (P < 0.01), WXVP was intermediate with other HSBM treatments and NC for P and S retention (P ≤ 0.02). Total N excretion was greater in WX, VP, and WXVP vs NC (P = 0.01), while enzyme supplemented diets did not differ from each other, PC and SD showed intermediate excretion levels similar to NC. Intake and digestibility of S and P increased with higher SBM, without increasing S and P excretion (P ≥ 0.12). Total Ca excretion was greater in WXVP vs VP (P = 0.03). Digestible and metabolizable energy values were similar across treatments (P ≥ 0.22). In conclusion, increasing SBM by 19% did not affect weight gain but increased intake and retention of N, P, Ca, and S, while dietary enzyme inclusion provided limited benefits in corn-soy diets, except for SD, which significantly improved Ca retention.

Two hundred and thirty-two PIC (PIC 1050, Genus, Hendersonville, TN) sows were used to investigate the effects of arginine supplementation in lactation diets on sow performance and litter growth rate. Sows were allotted by randomized complete block design to one of two dietary treatments formulated to different standard ileal digestible (SID) arginine levels. The control (CON) diet contained 0.9% SID arginine, while the experimental diet contained 1.07% SID arginine (ARG). Diets were formulated to meet or exceed all other NRC (2012) dietary recommendations. Sow body weight (BW), backfat (BF), and body condition score (BCS) were recorded upon entering the farrowing room and at weaning. Piglet litter weights were recorded after cross-fostering and at weaning to assess litter growth rate. Data were analyzed using generalized linear mixed models, with treatment as a fixed effect and group as a random effect. Models were fitted using R (v4.4.1), and results were considered significant at P ≤ 0.05 and a tendency at 0.50 < P ≤ 0.10. Sow and litter were considered the experimental unit. Sow lactation length and BW were not significantly different between treatments (P = 0.440 and 0.519, respectively). There was no significant difference in ADFI (P = 0.931). The supplementation of Arg did not change BCS at weaning (2.46, 2.47 (scale of 1-5); P = 0.919). Upon entering the farrowing room, the sow BF was 10.15 and 9.99 mm for the CON and Arg diets respectively. Change in BF after weaning was not significantly different between the CON (-0.946 mm) and the ARG (-1.31 mm) diets (P = 0.236). The number of pigs weaned per sow was not statistically different (P = 0.486). Starting litter weight was 19.1 kg for CON and 20.2 kg for ARG. Litter wean weight did not differ significantly between treatments (P = 0.695). Piglet average daily gain (ADG) differed significantly between treatments with a mean of 0.25 kg/d for CON and 0.24 kg/d for ARG (P = 0.029). Post-foster mortality was not changed with the addition of Arg with the CON post-foster mortality at 5.33% and the ARG mortality at 5.79% (P = 0.616). This resulted in the percent total livability of 78.5 (CON) and 75.3 (ARG) which was not significantly different (P = 0.258). In summary, arginine supplementation during lactation did not significantly influence sow performance or overall piglet growth and livability, except for a minor difference in piglet ADG.

Iowa State University (ISU) offers undergraduate certificates to demonstrate completion of a curriculum in a specialized area across a variety of disciplines. The certificate has the significant benefit of allowing students to customize their curriculum and document the completion of an approved course of study. A Companion Animal Science and Management Certificate is offered within the Animal Science Department at ISU. The certificate requirements are organized to correspond with faculty and employer-defined needs for a successful transition from ISU student to companion animal industry professional. The Companion Animal Science and Management Certificate will integrate technical topics in animal science with practical considerations in enterprise management. Two critical components to the certificate are completion of the Companion Animal Systems Management course and a required internship that focuses on companion animal science and management. Students that complete the certificate will have the background to identify and address challenges in modern companion animal enterprises. Further, the certificate will assist employers in identifying students that have shown the interest, discipline, and ability to complete this specialized study program.

Two hundred and forty pigs (27.62 ± 4.54 kg; Genus 337 x 1050; PIC, Hendersonville, TN) were allotted to split-sex pens (4 pigs/pen, 52 pens). In a completely randomized design, pigs were randomly assigned to one of four dietary treatments (n = 153 pens/treatment): 1) low soybean meal (SBM) diet (LSBM) supplemented with crystalline amino acids (AA), 2) medium SBM (MSBM) diet with moderate crystalline AA, 3) enhanced SBM (ESBM) diet replacing crystalline lysine with SBM, and 4) elevated soybean meal (ESBM+) diet replacing additional crystalline AA with SBM. Diets were formulated to meet or exceed NRC recommendations and were fed across three 28-day phases (SBM: 20–50%, 15–45%, 10–40%) from days 0–84. Growth performance was assessed by body weight (BW) and feed disappearance to calculate average daily gain (ADG), average daily feed intake (ADFI), and feed efficiency (G: F). The subset of 24 gilts were randomly selected on D0 and placed in metabolism stalls on days 10, 38, and 66 to evaluate nutrient digestibility, retention, and manure composition. Data were analyzed using Proc GLIMMIX MIXED in SAS 9.4 (Statistical Analysis System, Cary, NC) with pen or stall as the experimental unit. Treatment and dietary phase were fixed effects, and significance was set at P ≤0.05 and tendencies at 0.05 < P ≤0.10. Orthogonal linear contrasts were used to evaluate response changes in increased dietary CP. No treatment effects were observed for BW, ADG, or ADFI (P ≥0.39). Final BW was unaffected by diet (106.40 ± 1.028 kg; P = 0.59). A treatment effect on G: F in growth performance on the metabolism subset were observed in phase 3, with higher efficiency present in the MSBM-fed pigs compared to ESBM+, 0.42 vs. 0.28, respectively (P = 0.02). No significant differences were found in ATTD of DM, ash, OM, GE, N, or Ca (P >0.10). Phosphorus digestibility was lower in ESBM + compared to LSBM (P = 0.04). Sulfur digestibility tended to be lower in MSBM compared to LSBM (P = 0.07). Nitrogen, sulfur and phosphorus excretion increased linearly with SBM inclusion (P <0.01). Total carbon excretion tended to increase linearly as SBM increased (P = 0.06) while Ca excretion did not differ by SBM levels (P = 0.36). Manure pH and sulfur levels increased linearly with SBM inclusion (P <0.01). In conclusion, replacing crystalline AA with SBM did not negatively affect growth performance. Pigs fed MSBM had similar nutrient digestibility and retention to ESBM and ESBM+.

Amino acids are the foundation of numerous metabolic and physiological pathways for skeletal muscle accretion, internal organ development, skeletal development, and immune function. One widely studied subject in monogastric nutrition is dietary crude protein. However, birds do not have a crude protein requirement but have a clear requirement for essential amino acids. As individual amino acid requirements of swine and poultry are investigated and modern feed formulation tools and feed-grade amino acids are available cost-effectively, the dynamics of how we look at crude protein in the feed have evolved. With the modern tools available, nutritionists are able to formulate the feed to meet the amino acids required for optimal performance of animals. This approach reduces the excess nitrogen in the feed, making the diets friendlier for the gut, reducing substrates for harmful proliferating bacteria, reducing nitrogen excretion in manure, and improving the ecology and sustainability. Apart from growth, amino acids have a functional role in the metabolic and physiological pathways. Amino acids like threonine and arginine have additional functional roles in intestinal turnover, immune function, wound healing, vasodilation and oxidative, and heat stress alleviation. Such specific amino acids can be increased in the diet to support the physiological needs during the growth of animals without increasing the unwanted dietary nitrogen content. As the industry moves toward reducing crude protein while meeting the essential amino acid needs, more research is needed to understand the requirement of specific lower limiting and non-limiting amino acids as well as the dynamics of those amino acids in health, welfare, cost of production and ecological impact in poultry and swine production.

The objective of this study was to determine if the implementation of fiber in the diet would increase sow longevity, improve reproductive performance and the potential reduction of pre-puberty growth rate. Over 11,000 gilts (DNA Line 241, DNA Genetics, Columbus, NE) have been evaluated in this study. One thousand gilts at approximately 21 days of age were weaned every four weeks into the gilt development unit and were considered a single cohort. Gilts were housed in small pens (30-35 gilts); within a room. Feed and water were provided ad libitum throughout the trial. Gilts were given common diets until 42 days post wean (approximately 20 kg). Each cohort was assigned to either the standard diet (STD) or a slow growth (SG) diet. The STD consisted of corn, soybean meal, and DDGs whereas the SG diet had increasing levels of fiber (maximum of 50% inclusion of soyhulls) throughout the remaining dietary phases. Gilts from each cohort were sent to multiple farms where the animals continued to be evaluated for reproductive performance and longevity. A subset of gilts was evaluated in the gilt developer unit for growth and indicators of puberty. On day 111 pigs were vulva scored, on day 150 and 164 pigs were bled via jugular venipuncture for hormone analysis (estrogen, progesterone, and kisspeptin). On day 164 pigs were weighed, and ultra sound (EXAGO, IMV Technologies, Brookelyn Park, MN) for backfat (BF) and loin depth (LD) measurements. Approximately 935 pigs were followed through their first parity and their performance indicators were recorded. Feed was analyzed for gross energy using an isoperiodic bomb calorimeter (model 6200; Parr Instrument Co., Moline, IL) and sent to the University of Missouri Agricultural Experiment Station Laboratories (Columbia, MO) for amino acid, starch, and fiber analysis. Data were analyzed using SAS 9.4 (SAS Institute, Cary, NC) using proc GLIMMIX procedure. Results were considered significant if P≤0.05. Each cohort was considered the experimental unit. Adjusted days of age to 94 kg were significant with the STD at 155.4 ± 1.39 days and the SG at 164.3 ± 1.27 days. Vulva width (VW) was significant between dietary treatments with the STD having a larger vulva width compared to SG. Backfat was significantly different between dietary treatments with the STD group measuring 15.1mm and the SG measuring 12.5mm, respectively ±0.2mm. Loin Depth was not significantly between dietary treatments. The age to first breeding was significant with the STD group estimated at 217 days and the SG at 203 days ± 1.046 days. In conclusion supplementing fiber in growing gilt diets reduced growth rates and decreased back fat while also slowing the onset of puberty.

Two-hundred and forty pigs (PIC 337 x 1050, Genus, Hendersonville, TN); 27.62 ± 4.54 kg) were utilized to evaluate growth performance on growing pigs fed varying levels of soybean meal (SBM) diets. In a complete randomized design, pigs were randomly assigned to one of four dietary treatments (n = 15 pens/treatment; 4 pigs/pen). Dietary treatments consisted of: 1) low SBM (LSBM) corn-soy diet supplemented with crystalline amino acids, 2) medium SBM diet (MSBM) corn-soy diet with moderate crystalline amino acid inclusion, 3)Enhanced soybean meal diet (ESBM) with SBM formulated to replace all synthetic lysine equal to BCP in SID lysine, and 4) Elevated soybean meal (ESBM+) contained excess levels SBM to replace additional crystalline amino acids. The study was divided into three phases with SBM inclusion ranging from approximately 20-50%, 15-45%, and 10-40%. The dietary phases were fed from days 0-27, 28-55, and 56-84. Treatments 1-3 were formulated to the same SID Lys:ME for the three dietary phases (3.50, 3.08 and 2.57, respectively; however, in the ESBM+, the SID Lys:ME ratio was elevated (4.27, 3.87 and 3.44). Additionally, diets within each phase were isocaloric. Diets were formulated to meet or exceed all other nutrient recommendations (NRC, 2012). Pig body weight (BW) and feed disappearance were recorded at phase changes to calculate average daily gain (ADG), average daily feed intake (ADFI), and feed efficiency (G:F). Data were analyzed using Proc GLIMMIX in SAS 9.4 (Inst., Cary, NC) with pen as the experimental unit and the model included the fixed effect of treatment and dietary phase with least squares means reported. Results were considered significant at P ≤ 0.05 and a tendency at 0.05 < P ≤ 0.10. Overall, (d 0-84) pig ADFI or ADG did not differ across treatments (P ≥ 0.522). Ending body weight was not different across dietary treatments (BW = 106.07 ± 10.84 kg; P = 0.7336). However, GF was improved in pigs fed LSBM diets compared to ESBM+ (0.41 vs. 0.44; P < 0.05). No significant interaction between treatment and phase was observed in BW, ADFI or ADG (P > 0.1). A significant interaction between dietary treatment and phase was detected in GF (P = 0.0016), indicating that the effect of dietary treatment on GF depended on the phase. There were no differences across treatments in phase 2. There was an improvement in GF in pigs fed LSBM compared to ESBM in phase 1 (0.50 vs. 0.54; P = 0.038) and LSBM was improved in phase 3 compared to ESBM+ (0.35 vs. 0.39; P = 0.02). In conclusion, there were no negative growth performance effects of feeding diets containing minimal crystalline amino acids and meeting the requirement of the pigs via soybean meal.

Vitamin D and its metabolites are critical for bone health and structural integrity, with current requirements established for vitamin D but not 25-hydroxyvitamin D (25OHD3). Our objective was to evaluate dietary vitamin D3 and 25OHD3 concentrations on nursery pig growth performance, bone mineralization, and health. A total of 336 newly weaned pigs (5.2 ± 0.17 kg BW) were assigned to 1 of 8 dietary treatments (n=6 pens per treatment, 7 pigs per pen) using a randomized design. Diets were fed in two three-week phases over a six-week study. Corn soybean meal basal diets were formulated with a vitamin-mineral premix devoid of vitamin D. Dietary treatments included 0, 50, 200, and 400 IU/kg diet of added vitamin D and a basal diet containing 50 IU/kg vitamin D3 plus 0, 25, 50, 75, and 100 mg/MT 25OHD3. Pigs were weighed on days 0, 21, and 42, and feed disappearance was recorded to calculate ADG, ADFI, and Gain:Feed across phases and overall. On day 42, the median body weight pig in each pen was bled and euthanized. Whole body and femur bone mineral content (BMC) and bone mineral density (BMD) were assessed using dual-energy x-ray absorptiometry. Liver vitamin D3 and serum 25OHD2 concentrations were evaluated. Within each vitamin D3 and 25OHD3 titration, data were analyzed using a mixed linear model with a pen as the experimental unit, with additional linear and quadratic dietary treatment contrasts evaluated. In both vitamin D3 and 25OHD3 titrations, phase 1, phase 2, and overall ADG, ADFI, and GF did not differ. Serum 25 hydroxyvitamin D concentrations increased by 183% in pigs fed 2x NRC vitamin D3 (400 IU/kg) compared to 0 IU/kg (Linear P < 0.001). Additionally, compared to 0 IU/kg, liver D3 concentrations increased by 1534% in pigs fed 400 IU/kg vitamin D3 (Linear P < 0.001). As dietary 25OHD3 increased from 0 to 100 mg/MT, serum 25 hydroxyvitamin D concentrations increased from 2 to 78 ppb (Treatment P < 0.001). However, liver vitamin D3 did not differ as dietary 25OHD3 increased. Whole BMD increased by 8% in pigs fed the highest level of 25OHD3, with a linear increase across treatments (Treatment P = 0.044, Linear P = 0.004). As dietary vitamin D3 increased, whole body BMC increased from 317 to 365 g (Linear P = 0.046), and femur BMD tended to increase from 0.31 to 0.66 g/cm2 (Linear P = 0.071). Feeding increasing amounts of 25OHD3, whole body and femur BMD and BMC all increased (Linear P < 0.01). Compared to 0, 100 mg/MT 25ODD3 increased whole body BMD (0.58 vs. 0.63 g/cm2, Treatment P = 0.044). In conclusion, increased dietary vitamin D3 and 25OHD3 improve bone mineralization without impacting growth performance.

A total of 450 newly weaned pigs (PIC 337 x 1050, Genus, Hendersonville, TN) were used to evaluate the use of dietary ingredients to improve nursery pig gut health and growth performance. Pigs were sorted into pens (5 barrows and 5 gilts each (10 pigs/pen) and randomly assigned to one of five dietary treatments. The dietary treatments included: control (CN, standard diet with ZnO (3500 ppm); negative control (NC, control with no ZnO); sodium gluconate (SG, 0.25 % inclusion in NC, Sumitomo, Tokyo, Japan); butyrate (BP, 0.09% inclusion in NC, Kemin, Des Moines, IA) or monoglycerides (MG, 0.3% inclusion stepdown to 0.25% in NC, BASF, Florham Park, NJ). Diets were fed in three phases: 0-7 days, 7-21 days, and 21-42 days. Diets were formulated to meet or exceed all other NRC (2012) dietary recommendations. Pen and feeder weights were recorded on days 0, 7, 21, and 42 to calculate average daily gain (ADG), average daily feed intake (ADFI), and gain to feed (G:F). Data were analyzed using a linear model in R (v4.4.1) with significance set at P ≤ 0.05 and tendencies at 0.05 < P ≤ 0.10. Pen was the experimental unit. The pigs developed hemolytic Escherichia coli at approximately d10. The average starting pig body weight (BW) was 5.52 ± 0.123 kg. By day 21, the CN had significantly heavier BW compared to the other diets (10.58, 9.31, 9.55, 9.81, 9.24 kg, respectively; P < 0.01). Phase 1 ADG showed a significant difference with CN being higher than other diets (0.033, -0.017, -0.011, -0.008, -0.036; P < 0.01). ADG during phase 2 was significantly higher for the CN compared to other diets (0.332, 0.261, 0.274, 0.295, 0.237 kg/d; P < 0.01). Overall ADG (0.373, 0.329, 0.328, 0.345, 0.321 kg/d; P = 0.09) did show a tendency towards difference between diets. Overall G:F was 0.714, 0.756, 0.755, 0.759, and 0.746 kg, respectively, and showed no significant difference between diets (P = 0.66). ADFI during phase 2 showed a significant difference with the CN being higher than the other treatments (0.321, 0.246, 0.234, 0.248, 0.198; P < 0.01). Overall ADFI did show a significant difference for the CN diet (0.513, 0.438, 0.426, 0.463, 0.423; P < 0.01). Sodium gluconate, zinc oxide, and butyrate supplementation had limited effects on growth performance in nursery pigs, with zinc oxide showing the most notable differences. ADFI was improved overall when pigs were fed CN (zinc oxide) and some significant effects in early phases of ADG when feeding CN (zinc oxide), but these effects on ADG did span across the whole period.

Twenty-four gilts (PIC 337 x 1050; Genus, Hendersonville, TN) were utilized to evaluate nitrogen, sulfur, calcium, and phosphorus input and output on growing pigs fed varying levels of soybean meal diets. Pigs (36.77 ± 2.72 kg) were assigned to one of four dietary treatments and blocked by body weight (6 pigs/trt). Dietary treatments consisted of: 1) low SBM (LSBM) corn-soy diet supplemented with crystalline amino acids (AA), 2) medium SBM diet (MSBM) corn-soy diet with moderate crystalline AA inclusion, 3) Enhanced soybean meal diet (ESBM) with SBM formulated to replace all synthetic lysine equal to LSBM in SID lysine, and 4) Elevated soybean meal (ESBM+) contained excess levels SBM to replace additional crystalline AA. Gilts were a subset of a study, which had three 28-d dietary phases. Treatments 1-3 were formulated to the same SID Lys:ME for the three dietary phases (3.50, 3.08 and 2.57) and treatment 4 SID Lys:ME ratio was exceeded (4.27, 3.87 and 3.44).and SBM inclusion ranged from approximately 20-50%, 15-45%, and 10-40%. Additionally, diets within each phase were isocaloric and were formulated to meet or exceed all other nutrient recommendations (NRC, 2012). Gilts were placed into metabolism stalls on D10, 38, and 66. Pigs were blocked by BW on D10. Metabolism collections consisted of 72-hour acclimation period, followed by a 24-hour total collection of manure, a secondary 24-hour acclimation period, then a 72-hour total collection for nutrient balance. Manure were analyzed for pH. Nutrient balance collections assessed ME and DE, Ca, P, S, and N balance. Digestibility data were analyzed as repeated measures in SAS 9.4 (Inst., Cary, NC) with fixed effects of treatment, phase, and block. Pig served as the experimental unit, and significance set at P ≤ 0.05. Pigs fed LSBM had the lowest pH (P < 0.0001). There were no significant differences in ATTD of DM, ash, OM, GE, N, Ca, or S across treatments (P > 0.1). Phosphorus ATTD was lower in pigs fed ESBM+ compared to LSBM(P = 0.042). LSBM diets showed higher ME:DE efficiency across treatments (P < 0.05) and CD was also higher than HSBM (P = 0.0306). A significant interaction between dietary treatment and phase was detected in N intake, urinary P output, retention of percent digestible P, S intake, urinary S output, and total S excretion, Ca intake, urinary Ca output, total Ca excretion, Ca retention g/d, and Ca retention of percent digestible Ca (P < 0.05), indicating phase-dependent effects. Retention of percent intake of N was greatest in LP diets compared to all other treatments, and greater in P and S compared to ESBM+ (P < 0.05). Overall, pigs fed MSBM diets had similar nutrient utilization and excretion compared to ESBM and ESBM+ diets.

The objective of this study was to determine the energy value of soyhulls as well as determine if increasing levels of soyhulls alter nitrogen digestibility in gilts. Two repetitions were conducted using 24 gilts (PIC 337 X 1050, Genus, Hendersonville, TN) with a starting body weight (BW) of 45 kg ± 5 kg for 21 days. During the 21 days, gilts were allowed a 3-day acclimation period with a 4-day fecal and urine collection period for a total of 3 phases of sample collections. The four diets were formulated based on Lys:ME and contained varying levels of soyhulls (ADM Des Moines) starting with 0%, then increasing to 10%, 20%, 40%. Gilts remained on their respective diets for the duration of the study. Total urine and fecal excretion were collected for the 4-day period. Urine, fecal, feed, and soyhull samples were analyzed for total N and CP (TruMac N; LECO Corp., St. Joseph, MI) and gross energy using an iosperibolic bomb calorimeter (Model 6200; Parr Instrument Co., Moline, IL). Metabolizable energy was calculated using a prediction equation. Data were analyzed using SAS 9.4 (SAS Institute, Cary, NC) using the GLIMMIX procedure and pig was the experimental unit. Results were considered significant if P ≤ 0.05. Feed efficiency and feed intake were not significant across dietary treatments and replications, but significant across collection phases (P< 0.0001). Body weight was significant across phases and replications (P< 0.0001) but was not significant across treatments. ATTD (apparent total tract digestibility) of N (nitrogen) was significantly different across phase and treatments (P≤ 0.0001) and there was a tendency for a treatment by phase interaction (P< 0.0624). Fecal nitrogen output was significant across treatments (P≤0.0001) and phases (P< 0.0491). Total urine nitrogen output was significant across phases and treatments and there was a significant treatment by phase interaction (P ≤ 0.0001). Nitrogen retention was significant across phases (P≤0.0001). Metabolizable energy (ME) decreased as soyhulls were increased in the diets across all dietary treatments and collection phases. ME was significant between collection phases (P≤0.0001) and there was a tendency with dietary treatments (P< 0.0651). In conclusion, the increase in soyhulls up to 40% in the diet increases total urinary and fecal N output and the increase in soyhulls decreases metabolizable energy.

A total of 352 sows were used to investigate the effect of soybean meal (SBM) level and adjusted branched-chain amino acid (BCAA) balance on lactating sow and piglet performance. On day 112 ± 1.5 of gestation, sows were randomly assigned, within parity, to one of four dietary treatments: low SBM (LSBM), high SBM (HSBM), LSBM with adjusted BCAA (LSBM + BCAA), or HSBM with adjusted BCAA (HSBM + BCAA). The BCAA balance was adjusted to achieve equal standardized ileal digestible (SID) Ile:Leu:Val in the LSBM and HSBM + BCAA diets (SID Ile:Leu:Val 0.49:1.00:0.73) and in the HSBM and LSBM + BCAA diets (SID Ile:Leu:Val 0.54:1.00:0.58). All diets were formulated to be equal in SID Lys, isocaloric, and meet or exceed NRC (NRC. 2012. Nutrient requirements of swine. 11th rev. ed. Washington (DC). Natl. Acad. Press) recommendations for all other essential amino acids, vitamins, and minerals. Sow body weight (BW) and backfat thickness (BF) were measured at the time of entry into the farrowing room and at weaning. Litter weights were captured after cross-fostering and at weaning to calculate litter growth rate. Data were analyzed using generalized linear mixed models in R (v4.4.1; R Core Team, R Core Team. 2024. R: a language and environment for statistical computing. Vienna (Austria): R Foundation for Statistical Computing. https://www.R-project.org/) with fixed effects of dietary treatment, parity group, and their interaction and a random effect of lactation group. The sow and her litter were the experimental unit, and results were considered significant if P ≤ 0.05. There was an effect of the dietary treatments on sow average daily feed intake (ADFI; P < 0.001). Sows consuming the LSBM diet exhibited greater ADFI compared to HSBM (7.43 vs. 7.05 kg/d; P = 0.024) or HSBM + BCAA (7.43 vs. 6.87; P < 0.001), while sows fed LSBM + BCAA showed greater ADFI than HSBM + BCAA (7.24 vs. 6.87; P = 0.025), but similar ADFI to LSBM- (P = 0.515) and HSBM-fed (P = 0.466) fed sows. Despite differences in ADFI, sows gained an average of 7.1 kg of BW (P = 0.682) and lost 1.3 mm of BF (P = 0.928) through the lactation period. Sows started the trial with an average of 14.0 piglets/sow (P = 0.787) and weaned 12.6 piglets/sow (P = 0.875) with a piglet average daily gain of 0.22 kg/d (P = 0.646). Increasing SBM inclusion by 14% reduced sow ADFI in lactation by approximately 5% but did not alter sow BW or BF loss or piglet growth rate. While adjusting BCAA in the LSBM diet slightly reduced sow feed intake, adjusting BCAA in the HSBM diet did not alleviate the reduction in ADFI caused by elevated SBM, suggesting the balance of BCAA does not contribute to the feed intake response observed with elevated SBM inclusion in lactation diets.

Abstract Newly weaned pigs (n = 480; PIC 337 × 1050; Genus, Hendersonville, TN) with an initial body weight (BW) of 6.20 ± 0.61 kg were used in a dose-response study to evaluate the effects of increasing standardized ileal digestible (SID) Arg:Lys in nursery pigs. At weaning, pigs were placed into 48 pens with five barrows and five gilts per pen and randomly assigned to one of six dietary treatments. The experimental diets were formulated with increasing levels of SID Arg by replacing corn starch, glycine, and L-alanine with L-arginine. Levels of SID Arg:Lys ranged from 45 to 145%. Diets were sub-limiting in SID Lys and exceeded all other essential amino acid requirements. Furthermore, diets were formulated to be isocaloric, isonitrogenous, and met or exceeded NRC (2012) vitamin and mineral recommendations. The experimental diets were fed in two feeding phases from d 0 to 10 and d 10 to 27, with adjustments made to account for the decreasing Lys requirement of the pigs. Pigs were subsequently fed a common diet for the remaining 14 d of the nursery period to determine carryover effects. Pigs and feeders were weighed at the beginning and end of each dietary phase for the calculation of average daily gain (ADG), average daily feed intake (ADFI), and feed efficiency (gain to feed ratio; G:F). The data were fit using linear regression with R version 4.3.1 (R Core Team, 2023). The model included linear and quadratic effects of SID Arg:Lys and initial BW. Pen was the experimental unit, and results were considered significant at P ≤ 0.05 and a tendency at 0.05 < P ≤ 0.10. There was a significant linear and quadratic effect of SID Arg:Lys on BW on d 27 (P ≤ 0.024), where BW was maximized at a SID Arg:Lys 97.09%. From d 0 to 27 there was a linear and quadratic tendency of SID Arg:Lys on ADFI (P = 0.069), where feed intake was maximized at a SID Arg:Lys of 97.00%. Furthermore, there tended to be a linear and quadratic effect of SID Arg:Lys on ADG from d0 to 27 (P ≤ 0.081), where ADG was maximized at a SID Arg:Lys of 95.65%. There was no evidence for an effect of SID Arg:Lys on G:F at any timepoint throughout the trial (P ≥ 0.298). In conclusion, SID Arg:Lys linearly and quadratically impacted ADFI and ADG in 6 to 13 kg nursery pigs, where ADG was maximized at a SID Arg:Lys of 95.65%, but ADFI was maximized at a SID Arg:Lys of 97.00%. Together, these data suggest that the SID Arg:Lys requirement of nursery pigs is greater than NRC (2012) recommendations, and excessive Arg supplementation may have negative consequences on growth performance.