Digestibility of energy and concentrations of metabolizable energy and net energy varies among sources of bakery meal when fed to growing pigs.

The null hypothesis that there are no differences in concentrations of digestible energy (DE), metabolizable energy (ME), and net energy (NE) among different sources of bakery meal was tested in a regional experiment involving 5 of the universities on the North Central Coordinating Committee-42 on Swine Nutrition. Eleven sources of bakery meal were procured from the swine producing areas in the United States and included in one diet as the only energy containing ingredient, and each diet was then divided into 5 batches that were used at the University of Illinois, Purdue University, University of Kentucky, University of Nebraska, and North Carolina State University. At each university, diets were fed to 22 growing pigs (2 pigs per diet) that were placed in metabolism crates, and feces and urine were collected for 5 d after a 7-d adaptation period. Diets and collected samples of feces and urine were dried and analyzed for gross energy. The apparent total tract digestibility of dry matter (DM) and gross energy and concentrations of DE, ME, and NE were calculated. Results indicated that there were considerable variation in the nutritional composition among the different sources of bakery meal with relatively large coefficients of variation for crude protein, starch, and acid hydrolyzed ether extract, but it was possible to analyze all sources of bakery meal to account for 100% of the ingredients. The average DE, ME, and NE in the 11 sources of bakery meal was 3,827, 3,678, and 2,799 kcal/kg DM, respectively. However, in contrast to the hypothesis, differences (P < 0.05) among sources of bakery meal in concentrations of DE (3,827 ±â€…201 kcal/kg DM), ME 3,678 ±â€…200 kcal/kg DM), and NE (2,799 ±â€…156 kcal/kg DM) were observed, but the variation among the 11 sources of bakery meal was not greater than what is usually observed among different sources of other ingredients. The differences observed are likely a consequence of the different product streams and production procedures used to produce the bakery meal. In conclusion, the average DE, ME, and NE in 11 sources of bakery meal is close to values previously reported, but there is some variation among sources depending on origin.

An experiment was conducted at 5 universities to determine digestible energy (DE), metabolizable energy (ME), and net energy (NE) by growing pigs in 11 sources of bakery meal that were sourced from swine producing states in the United States. Each source was analyzed and included in a diet as the only source of energy. Diets were fed to growing pigs that were housed in metabolism crates and fecal and urine samples were collected. Values for DE and ME were calculated from analyzed energy in diets, feces, and urine, and NE was calculated using a prediction equation. Results indicated that it was possible to analyze each source of bakery meal to 100%. The average DE, ME, and NE was 3,827, 3,678, and 2,799 kcal/kg dry matter. Although some variability among the 11 sources of bakery meal was observed, the variability in DE and ME values in bakery meal was not greater than what is observed in most other normally used feed ingredients.

Effects of restricting energy during the gilt development period on growth and reproduction of lines differing in lean growth rate: responses in reproductive performance and longevity.

Longevity and reproductive performance are economically important traits in the swine industry that are largely influenced by nutrition and other environmental factors. Reproductive performance and longevity through 4 parities was assessed in gilts of 2 genetic lines developed on ad libitum access to feed or restricted to 75% of ad libitum intake. A total of 661 gilts were used in a 2 × 2 factorial with half of the gilts allocated to an ad libitum diet (AL; n = 330), while the other half were energy restricted by 25% (R; n = 331) from 123 to 235 d of age. All gilts were sired by an industry maternal line. Dams of the gilts were from either a Large White (W) by Landrace (L) industry maternal line or Nebraska Selection Line 45X, producing gilts designated as W × L (n = 355) and L45X (n = 306), respectively. Daily estrus detection began at 140 d of age to obtain age at puberty (AP). Gilts (n = 510) were mated on their second or later estrus, beginning at 240 d of age. Sow weight and backfat were recorded at 110 d of gestation and weaning of each parity. Number of live-born, stillborn, and mummified pigs per litter and piglet birth and weaning weights were recorded through 4 parities. More L45X than W × L and more AL than R gilts reached puberty by 230 d of age (P < 0.01). Dietary treatment did not affect probability to produce parities 1 to 4 or any litter trait analyzed. The L45X females tended to be more likely to produce parities 1 (P < 0.08) and 3 (P < 0.06), while W × L had heavier litters at birth (P < 0.01) and weaning (P = 0.01). Treatment by parity interactions (P < 0.01) existed for weight and backfat prior to farrowing and backfat at weaning, and weight at weaning exhibited a line by treatment by parity interaction (P = 0.04) as R sows had lower weights and backfats in earlier parities, but caught up to AL sows in later parities. A treatment by parity interaction (P < 0.01) was also present for backfat loss from farrowing to weaning as R gilts lost less backfat than AL in parities 1 and 2, but more in parities 3 and 4. No significant differences were detected between lines or treatments for lifetime production traits. The populations of pigs and data presented here provide a framework for a diverse array of further studies. Alternative approaches to restrict energy have been assessed in addition to methods of marker-assisted and genomic selection for improvement of litter size and sow longevity.

Effects of mannan oligosaccharides and Lactobacillus mucosae on growth performance, immune response, and gut health of weanling pigs challenged with Escherichia coli lipopolysaccharides.

Addition of pre- and probiotics may confer growth and health benefits when added to the diet of pigs. To determine the effects of feeding mannan oligosaccharide (MOS) and Lactobacillus mucosae (LM) as prebiotic and probiotic sources in weanling pigs under immune challenge, 96 weaned pigs were randomly allotted to 16 experimental pens within a 2 × 2 factorial arrangement of treatments. Control diets with or without 0.1% yeast-derived MOS were randomly assigned to pens and 109 cfu/pig LM broth or a control broth were top-dressed daily. Pigs were fed one of four dietary treatments (control, MOS, LM, and MOS+LM) in Phases I and II (days 0 to 7 and days 7 to 21 postweaning, respectively) and a common diet during Phase III (days 21 to 35 postweaning). On day 14, all pigs were challenged with 100 µg/kg body weight (BW) Escherichia coli lipopolysaccharide (LPS) via intraperitonial injection. Feed disappearance and pig BW were measured weekly. Blood and fecal samples were collected weekly, and additional blood samples were collected on days 1 and 3 post-LPS challenge. On days 15 and 21, one pig per pen was euthanized for collection of ileal mucosa and duodenal and ileal tissue samples. From days 0 to 14, feeding LM decreased gain-to-feed ratio (G:F; P < 0.05). An interaction between LM and MOS was observed for G:F on days 14 to 21 (P < 0.05); G:F in LM (715 g/kg) was greater compared with MOS+LM (P < 0.05; 600 g/kg) and control (P < 0.10; 615 g/kg), but was not different (P > 0.10) from MOS (674 g/kg). After pigs were fed a common diet (days 21 to 35), G:F was decreased (P < 0.05) in the LM treatment groups. Pigs fed diets that included MOS had increased serum immunoglobulin (Ig) G on days 1 and 3 post-LPS challenge and 2 wk after removal of treatments (P < 0.05) and on days 14 and 21 postweaning (P < 0.10) compared with pigs fed diets without MOS. On day 15, mucosal immunoglobulin G was increased (P < 0.05) in control vs. MOS and LM groups. Circulating IL-1ß in control and MOS+LM pigs increased (P < 0.05) on day 1 post-LPS challenge but did not change (P > 0.10) in MOS and LM groups. On day 15, pigs fed LM had decreased (P < 0.05) ileal crypt depth compared with pigs fed the control diet. On day 21, fecal propionate and butyrate tended to be lower (P < 0.10) in pigs fed MOS vs. control and MOS+LM diet. These preliminary findings suggest that feeding LM alone improved feed efficiency and ileal morphological structure during the first week of LPS challenge; additionally, feeding LM and MOS may have beneficial effects relative to immune biomarkers.

ASAS-NANP SYMPOSIUM: RUMINANT/NONRUMINANT FEED COMPOSITION: Challenges and opportunities associated with creating large feed composition tables.

Traditional feed composition tables have been a useful tool in the field of animal nutrition throughout the last 70 yr. The objective of this paper is to discuss the challenges and opportunities associated with creating large feed ingredient composition tables. This manuscript will focus on three topics discussed during the National Animal Nutrition Program (NANP) Symposium in ruminant and nonruminant nutrition carried out at the American Society of Animal Science Annual Meeting in Austin, TX, on July 11, 2019, namely: 1) Using large datasets in feed composition tables and the importance of standard deviation in nutrient composition as well as different methods to obtain accurate standard deviation values, 2) Discussing the importance of fiber in animal nutrition and the evaluation of different methods to estimate fiber content of feeds, and 3) Description of novel feed sources, such as insects, algae, and single-cell protein, and challenges associated with the inclusion of such feeds in feed composition tables. Development of feed composition tables presents important challenges. For instance, large datasets provided by different sources tend to have errors and misclassifications. In addition, data are in different file formats, data structures, and feed classifications. Managing such large databases requires computers with high processing power and software that are also able to run automated procedures to consolidate files, to screen out outlying observations, and to detect misclassified records. Complex algorithms are necessary to identify misclassified samples and outliers aimed to obtain accurate nutrient composition values. Fiber is an important nutrient for both monogastrics and ruminants. Currently, there are several methods available to estimate the fiber content of feeds. However, many of them do not estimate fiber accurately. Total dietary fiber should be used as the standard method to estimate fiber concentrations in feeds. Finally, novel feed sources are a viable option to replace traditional feed sources from a nutritional perspective, but the large variation in nutrient composition among batches makes it difficult to provide reliable nutrient information to be tabulated. Further communication and cooperation among different stakeholders in the animal industry are required to produce reliable data on the nutrient composition to be published in feed composition tables.

Differential longitudinal establishment of human fecal bacterial communities in germ-free porcine and murine models.

The majority of microbiome studies focused on understanding mechanistic relationships between the host and the microbiota have used mice and other rodents as the model of choice. However, the domestic pig is a relevant model that is currently underutilized for human microbiome investigations. In this study, we performed a direct comparison of the engraftment of fecal bacterial communities from human donors between human microbiota-associated (HMA) piglet and mouse models under identical dietary conditions. Analysis of 16S rRNA genes using amplicon sequence variants (ASVs) revealed that with the exception of early microbiota from infants, the more mature microbiotas tested established better in the HMA piglets compared to HMA mice. Of interest was the greater transplantation success of members belonging to phylum Firmicutes in the HMA piglets compared to the HMA mice. Together, these results provide evidence for the HMA piglet model potentially being more broadly applicable for donors with more mature microbiotas while the HMA mouse model might be more relevant for developing microbiotas such as those of infants. This study also emphasizes the necessity to exercise caution in extrapolating findings from HMA animals to humans, since up to 28% of taxa from some donors failed to colonize either model.

The effects of prebiotics on growth performance and in vitro immune biomarkers in weaned pigs.

The objective of the experiment was to investigate the effects of prebiotics in nursery pigs on growth performance and immune biomarkers. Sixty-four weaned pigs (31 ± 1 d; BW 8 ± 0.1 kg) of mixed gender were housed (4 pigs/pen) in an environmentally controlled nursery with ad libitum access to feed and water over a 35-d study. Pigs were randomly assigned to one of four treatments: control (53% corn, 32% SBM, 7% fishmeal, 8% others), control + 2.5% GroBiotic-S (GS), control + 0.05% chicory (CL), or control + 0.5% chicory (CH). Feeders and pigs were weighed weekly. On day 21, blood samples were obtained from three pigs/treatment for collection of peripheral blood mononuclear cells (PBMC). Isolated PBMC were cultured and subsequently challenged with lipopolysaccharide (LPS; 20 ng/mL). Cell culture supernatants were collected for quantification of the pro- and anti-inflammatory cytokines, interleukin (IL)-8 and IL-10, respectively. Dietary treatment had no effect on BW. At days 28 to 35, pigs fed GS (790 ± 15 g), CL (704 ± 15 g), or CH (692 ± 15 g) had greater (P < 0.05) ADG compared with control (643 ± 15 g) pigs. In addition, overall (days 0-35), pigs fed GS (823 ± 18 g), CL (783 ± 18 g), or CH (782 ± 18 g) had greater (P < 0.05) ADFI compared with control, and ADFI for GS-fed pigs was greater (P < 0.05) than either CL or CH. There was no difference in G:F among treatments. In vitro LPS challenge increased (P < 0.05) IL-8 secretion from PBMC isolated from CL (23,731 ± 3,221 pg/mL) pigs compared with control (10,061 ± 3,221 pg/mL) and CH (12,411 ± 3,221 pg/mL) pigs. Secretion of IL-10 from PBMC isolated from CL (63 ± 9 pg/mL) pigs was greater (P < 0.05) compared with control (22 ± 9 pg/mL) pigs and tended (P < 0.1) to be greater compared with CH (34 ± 9 pg/mL) pigs. Results indicate that inclusion of prebiotics in nursery pig diets has positive effects on growth performance and may have immunomodulatory effects (in vitro) on cells isolated from prebiotic-fed pigs.

Effects of spray-dried porcine plasma on fecal microbiota in nursery pigs.

Spray-dried porcine plasma (SDPP) has been considered as an alternative for in-feed antibiotics to improve pig growth performance; however, the effect of SDPP on gut microbiota is unknown. The objective of this study was to evaluate effects of feeding SDPP on fecal microbial communities of nursery pigs. Ninety-six weaned pigs were assigned to 16 pens, which were allotted to two dietary treatments, including the control or the control + SDPP (5% and 2.5% SDPP inclusion in phase 1 and 2, respectively) diet. Fecal samples were collected at d 0, 7, 14, 21, and 28. Multiplex sequencing of V3 region of the 16S rRNA gene was used to characterize the bacterial community structure of fecal samples. Pearson's correlation tests were performed in Calypso to identify bacterial taxa that were either positively or negatively associated with overall growth performance. Feeding SDPP altered microbial structure at family, genus, and operational taxonomic unit (OTU) classifications; however, fecal microbes shifted with time. At the family level, Clostridiaceae increased (P < 0.001) on d 14, but decreased (P < 0.05) on d 28 in SDPP-fed pigs compared with control pigs. Decreased Veillonellaceae (P < 0.05; d 14) and Lachnospiraceae (P = 0.001; overall) were observed in SDPP-fed pigs compared with control pigs. Feeding SDPP increased lactic acid-producing bacteria (Lactobacillus delbrueckii, d 7) and cellulolytic bacteria (Ruminococcus albus, d 7; Clostridium thermocellum, d 7 and 14; and Clostridium saccharoperbutylacetonicum/beijerinckii, d 14; and Megasphaera elsdenii, d 21). On d 28, feeding SDPP decreased (P < 0.05) Clostridium difficile compared with control pigs. In conclusion, feeding SDPP altered fecal microbial communities in nursery pigs. The results of this study may provide information to help explain the positive effects associated with feeding SDPP on nutrient digestibility and gut health of nursery pigs.

Effects of energy restriction during gilt development on milk nutrient profile, milk oligosaccharides, and progeny biomarkers.

An ongoing study at the University of Nebraska-Lincoln (which included 14 batches of gilts; n = 90 gilts/batch) demonstrated that energy restriction during the developmental period of a gilt increases longevity and may also have beneficial effects on progeny health and growth, particularly, parity 1 progeny. Therefore, we hypothesized that energy restriction during gilt development may affect milk nutrient profile, milk oligosaccharides (OS), and postnatal progeny biomarkers. During the development period, batch 14 gilts (n = 128, 8 gilts/pen) were fed 3 dietary treatments including the following: 1) Control diet formulated to NRC (2012) specifications (CTL); 2) Restricted (20% energy restriction via addition of 40% soy hulls; RESTR); and 3) CTL diet plus addition of crystalline amino acids equivalent to the SID Lys:ME of the RESTR diet (CTL+). All diets were fed ad libitum and applied in a 3-phase feeding regimen during gilt development (days 123 to 230 of age). Average daily feed intake was used to estimate daily metabolizable energy intake (Mcal/d) during each phase (Phase 1: 10.13, 6.97, 9.95; Phase 2: 11.25, 8.05, 10.94; and Phase 3: 9.47, 7.95,11.07) for CTL, RESTR, and CTL+, respectively. After 230 d of age, gilts were bred and fed a common diet. Milk samples were collected from batch 14 gilts (n = 7 per treatment) on days 0 and 14 postfarrowing for compositional analysis of N, CP, dry matter (DM), GE, insulin, and OS. Piglet blood samples (n = 6 piglets/gilt) were obtained on days 1 and 15 postfarrowing for quantification of glucagon-like peptide-2 (GLP-2) and insulin. No effects of developmental diet were observed for milk N, CP, DM, or GE; however, N, CP, DM, and insulin were increased (P < 0.05) on day 1 compared with day 14. A total of 61 different milk OS were identified. Milk OS profile was significantly different for neutral and acidic OS (P < 0.05) on day 0, but there were no significant differences on day 14. For piglet GLP-2, a treatment by day interaction was observed (P < 0.009); specifically, on day 1 GLP concentrations were greater (P < 0.001) in CTL+ compared with RESTR (6.73 vs. 1.21 ng/mL). For serum insulin, a treatment by day interaction was observed (P < 0.01); specifically, insulin in RESTR progeny was greater (P < 0.03) than CTL on day 1. In conclusion, nutritional management of the developing gilt may affect milk nutrient composition, milk OS profile, and piglet serum biomarkers.

Evaluating equations estimating change in swine feed intake during heat and cold stress.

The objectives of this study were to evaluate heat stress feed intake models for growing swine using a data set assembled from the literature and to develop a series of new equations modeling the influence of the thermal environment and interactions between the thermal environmental and other factors on feed intake. A literature survey was conducted to identify studies assessing intake responses to temperature. The resulting data set comprised 35 studies containing 120 comparisons to thermoneutral intake. Intake as a fraction of thermoneutral intake (FFI) was the primary response variable, where a value of 1 represented no change from thermoneutral intake. The FFI predicted by NRC and a recent model from a meta-analysis (Renaudeau et al.,) were compared to observed values. New parameters for the NRC equation (NRCmod) were derived, and a series of new equations incorporating duration of exposure (TD), temperature cycling (TC), and floor type (TH) were also derived. Root-mean-square prediction error (RMSPE) and concordance correlation coefficients were used to evaluate all models. The RMSPE for the NRC model was 23.6 with mean and slope bias accounting for 12.6% and 51.1% of prediction error, respectively. The TD, TC, and TH models had reduced RMSPE compared with NRC: 12.9 for TD, 12.6 for TC, and 12.9 for TS. Substantial improvements were also made by refitting parameters (NRCmod; RMSPE 13.0%). In NRCmod, TD, TC, and TH, random error was the predominant source, accounting for over 97% of prediction error. The Renaudeau et al. model was also evaluated. Renaudeau et al. had relatively low RMSPE (22.3) for intake but higher RMSPE for FFI (22.6) than NRC, NRCmod, TD, TC, or TH. Additional parameters were derived for the Renaudeau et al. equation to account for housing system and diet characteristics. This adjustment reduced RMSPE of predicting feed intake (16.0) and FFI (16.3) and reduced systematic bias in the equation. This evaluation of equations highlights the effects of novel explanatory variables on feed intake during heat stress, and the comparison can be useful when selecting a model that best explains variability in feed intake responses to heat stress given available input data.

Phosphorus fractionation in manure from swine fed traditional and low-phytate corn diets.

Traditional corn (Zea mays L.) (TC), the primary grain used in swine (Sus scrofa) diets, stores a majority of its P as phytate, which is largely unavailable for digestion by nonruminant animals. Low-phytate corn (LPC) contains similar amounts of total P but a smaller percentage of P as phytate. When fed to swine, LPC increases P utilization and reduces P content of manure. While differences in P content between manure from animals fed TC and LPC diets have been documented, solubility and lability of manure P have not been compared. Manure P was characterized in manure from swine fed either LPC or TC diets in 2000 and 2001. Total P was lower (20 vs. 34 g kg(-1)) and N to P ratio was higher (4.5 vs. 3.3) in LPC manure than in TC manure. Manures were sequentially extracted with deionized water, 0.5 M NaHCO3, 0.1 M NaOH, and 1.0 M HCl. Extracts were analyzed for inorganic and total P. Most P (approximately 80%) in the extracts was in the inorganic form. Concentration of P in the water-extractable fraction was lower for LPC manure (10.2 g kg(-1) in 2000 and 9.7 g kg(-1) in 2001) than for TC manure (13.6 g kg(-1) in 2000 and 17.0 g kg(-1) in 2001). Percentage of total P in each extract was in the order of: H2O (60%), HCl (22%), NaHCO3 (12%), NaOH (8%), and residue (<1%). Total P and distribution of P in extracts indicates swine are able to utilize more P contained in LPC feed but the composition of P excreted in LPC manure is similar to TC manure. Solubility, crop availability, and lability of P in LPC manure should be similar to that of TC manure.