Effects of formulating growing pig diet with increasing levels of wheat-corn distillers dried grains with solubles on digestible nutrient basis on growth performance and nutrient digestibility

The Adaptive Alternation of Intestinal Microbiota and Regulation of Host Genes Jointly Promote Pigs to Digest Appropriate High-Fiber Diets

Although studies have revealed the significant impact of dietary fiber on growth performance and nutrient digestibility, the specific characteristics of the intestinal microbiota and gene regulation in pigs capable of digesting high-fiber diets remained unclear. To investigate the traits associated with roughage tolerance in the Chinese indigenous pig breed, we conducted comparative analysis of growth performance, apparent fiber digestibility, intestinal microbiota, SCFA concentrations and intestinal transcriptome in Tunchang pigs, feeding them diets with different wheat bran levels. The results indicated that the growth performance of Tunchang pigs was not significantly impacted, and the apparent total tract digestibility of crude fiber was significantly improved with increasing dietary fiber content. High-fiber diets altered the diversity of intestinal microbiota, and increased the relative abundance of Prevotella, CF231, as well as the concentrations of isobutyrate, valerate and isovalerate. The LDA analysis identified potential microbial biomarkers that could be associated with roughage tolerance, such as Prevotella stercorea, and Eubacterium biforme. In addition, appropriate high-fiber diets containing 4.34% crude fiber upregulated the mRNA expressions of PYY, AQP8, and SLC5A8, while downregulating the mRNA expressions of CKM and CNN1.This indicated that appropriate high-fiber diets may inhibit intestine motility and increase the absorption of water and SCFAs.

Influence of Fermented Broccoli Residues on Fattening Performance, Nutrient Utilization, and Meat Properties of Finishing Pigs

The study determined the impacts of dietary fermented residues' (FBR) inclusion on growth, nutrient utilization, carcass characteristics, and meat properties in fattening pigs. Seventy-two robust pigs were randomly assigned to two experimental groups (Duroc × Landrace × Yorkshire, thirty-six pigs each). Each group was subjected to a 52-day trial, during which they received either a corn-soybean meal-based diet or diet enhanced with a 10% addition of FBR. Consequently, adding 10% FBR caused a significant decrease in the digestive utilization of crude dietary components in fattening pigs (p < 0.05) but showed no significant impact on the growth performance. Additionally, FBR inclusion increased the marbling scores (p < 0.05) and total antioxidant functions (p < 0.05) of muscle tissues, indicating improved meat quality. Gender affected backfat depth, with barrows showing thicker backfat depth. In conclusion, dietary supplementation with 10% FBR in finishing pigs influenced the meat quality by improving the marbling score and antioxidant performance while reducing digestibility without compromising growth performance.

Effects of low protein diets on acid-base balance, electrolyte balance, intestinal structure, and amino acid transport in piglets

Reducing the dietary crude protein (CP) could effectively reduce pressure on protein ingredient supplies. However, few data have been reported about the extent to which CP can be reduced and whether limiting the use of soybean meal leads to electrolyte imbalance. In this experiment, using the low protein (LP) diet [2% lower than NRC (2012)], seventy-two piglets (35 days old) were randomly divided into 2 groups with 6 replicates of 6 piglets each: CON group (CP = 18.5%) and LP group (CP = 16.5%), to investigate the effect of the LP diet on electrolyte balance, acid-base balance, intestinal structure and amino acid transport in piglets. The results revealed that the LP diet decreased the average daily gain and dietary CP digestibility, and damaged the villi structure of the small intestine. Compared with the CON diet, the potassium content decreased and the chlorine content increased in the LP diet, and similar trends were shown in piglet serum. The arterial pH, pCO2, HCO3 -, and base excess of piglets in the LP group were lower than those in the CON group, while pO2 was higher than those in the CON group. Interestingly, the LP diet significantly increased the lysine content in piglet serum and significantly decreased the levels of arginine, leucine, and glutamic acid. Furthermore, the LP diet significantly affected the expression of some amino acid transport vectors (B0AT1, EAAC1, and y+LAT1). In summary, these findings suggested that the LP diet leads to acid-base imbalance, amino acid transport disorder and amino acids imbalance in piglets, and the dietary electrolyte may be a key factor in the impact of the LP diet on piglet growth performance and intestinal health.

Dietary addition of fermented sorghum distiller's dried grains with soluble improves carcass traits and meat quality in growing-finishing pigs

The fermented sorghum distiller's dried grain with soluble (FS-DDGS) contains numerous nutrients, yet its nutritional effects on growing-finishing pigs remain unclear. The present study evaluated the effects of dietary FS-DDGS addition on growth performance, carcass traits, and meat quality in growing-finishing pigs. A total of 48 healthy male crossbred (Large White × Landrace × Duroc) barrows with initial body weight (BW) of 39.95 ± 2.15 kg were allocated to one of four dietary treatments (12 pigs per treatment). The dietary treatments were as follows: basal diet without (FS-DDGS0 group) or with 50 g/kg (FS-DDGS50 group), 100 g/kg (FS-DDGS100 group), or 150 g/kg (FS-DDGS150 group) FS-DDGS, respectively. Results showed that there were no significant differences in the final BW, average daily gain, average daily feed intake, and feed to gain ratio among these four groups. However, dietary FS-DDGS addition increased (linear, P < 0.05) the pH_24h value, contents of ash, crude protein, and proline in Longissimus dorsi muscle, and alanine, arginine, aspartic acid, glutamic acid, isoleucine, leucine, lysine, serine, and tyrosine in Biceps femoris (BF) muscle, when compared with the control group. In addition, dietary FS-DDGS addition decreased (linear, P < 0.05) the drip loss, yellowness (b*) value, and lightness (L*) value, while quadratically improved (P < 0.05) the total bone percentage and glycine and proline contents in BF muscle compared with the control group. Collectively, these findings suggested that dietary FS-DDGS addition could improve the carcass traits and meat quality in growing-finishing pigs although further research is needed to explore the underlying mechanisms.

Effects of short-term moderate ZEN consumption on uterosacral ligament elasticity in pubertal gilts

Zearalenone (ZEN) is a potent estrogenic toxin in swine, contributing to economic losses in herds via reproductive consequences such as pelvic organ prolapse (POP). To better understand the relationship between ZEN-consumption and reproductive symptoms, an animal feeding study with pubertal gilts was designed. The gilts were exposed to three different treatments: solvent-only feed for 21 days (n = 10), ZEN-spiked feed for 7 days followed by solvent-only feed for 14 days (n = 10), and ZEN-spiked feed for 21 days (n = 10). The gilts did not display any ZEN-related symptoms throughout any of the treatments. At the end of the trial the elastic properties of the USLs from participating gilts were evaluated along two loading directions: main direction (MD) and perpendicular direction (PD). The elastic properties included average stresses at 2% and 4% strains, and secant moduli. Overall the elastic properties of the USLs did not vary across treatment groups or between loading directions. In the MD, average stress increased from 32.96 ± 4.43 kPa at 2% strain to 63.21 ± 9.69 kPa at 4% strain, with a secant modulus of 1.52 ± 0.27 MPa. In the PD, average stress increased from 40.82 ± 4.22 kPa at 2% strain to 83.38 ± 9.17 kPa at 4% strain, with a secant modulus of 2.13 ± 0.31 MPa. Continued research into the relationship between ZEN consumption and reproductive symptoms such as POP is necessary in order to mitigate their deleterious effects in herds.

Quantification of zearalenone and α-zearalenol in swine liver and reproductive tissues using GC-MS

The mycotoxin zearalenone (ZEN) is a common contaminant of swine feed which has been related to a wide range of reproductive anomalies in swine, such as pelvic organ prolapse, anestrous, and pseudopregnancy. New information is needed to understand how ZEN and related metabolites accumulate in swine reproductive tissues. We conducted a feeding study to track ZEN and the metabolite α-zearalenol (α-ZEL) in swine liver and reproductive tissues. Thirty pubertal gilts were randomly assigned one of three treatments, with ten pigs in each treatment group: (1) base feed with solvent for 21 days, (2) ZEN-spiked feed for seven days followed by base feed with solvent for 14 days, and (3) ZEN-spiked feed for 21 days. At the end of the trial, liver, anterior vagina, posterior vagina, cervix, uterus, ovaries, and broad ligament were collected from pigs. ZEN was found in the anterior vagina, posterior vagina, cervix, and ovaries, with significantly higher concentrations in the cervix relative to other reproductive tissues. ZEN and α-ZEL were found in liver tissue from pigs in each treatment group. Our results show that ZEN accumulates more in the cervix than other reproductive tissues. The presence of ZEN in reproductive tissues may be indicative of ZEN-related reproductive symptoms. Future work could examine how ZEN concentrations vary in reproductive tissues as a factor of the pigs age, weight, sex, or parity, to establish parameters that make pig more sensitive to ZEN.

•

A feeding trial was conducted where gilts consumed varying amounts of zearalenone.

•

Zearalenone was found in the anterior vagina, posterior vagina, cervix, and ovaries.

•

Zearalenone concentrations were highest in the cervix.

•

Zearalenone and alpha-zearalenol were found in the liver.

Impact of rare earth element-enriched yeast on growth performance, nutrient digestibility, blood profile, and fecal microflora in finishing pigs

This study was conducted to evaluate effects of rare earth element-enriched yeast (RY) on growth performance, nutrient digestibility, blood profile, and fecal microbial flora in finishing pigs. A total of 100 finishing pigs [(Landrace × Yorkshire) × Duroc] were used in a two-phase feeding trial. Pigs were randomly assigned to five treatments according to their initial body weight (five pens per treatment, two gilts and two barrows per pen). Treatments were basal diets, free of antibiotics [negative control (NC)]; NC + 500, 1000, and 1500 mg kg−1, respectively, of RY; antibiotics diets, NC + 500 mg kg−1 of tiamulin [positive control (PC)]. Overall, average daily gain (ADG) and gain to feed ratio (G:F) increased linearly with increasing level of RY in diets. At the end of the experiment, blood lymphocyte concentration and apparent total tract digestibility of dry matter and gross energy increased linearly in pigs fed the increasing level of RY in diets. The better ADG, G:F, and fecal Lactobacillus counts were observed in both RY and PC groups compared with the NC group. In conclusion, diets with RY improved growth performance, digestibility, blood lymphocyte counts, and fecal Lactobacillus counts in finishing pigs, and RY may be considered as an alternative to antibiotics.

Nutrient profile and digestibility of tubers and agro-industrial coproducts determined using an in vitro model of swine

Exploring and evaluating alternative feed ingredients to be used in swine diet is essential due to highly variable cost and limited availability of conventional feed ingredients. Tubers and agro-industrial coproducts could provide the basis for producing affordable swine feed. However, information on the nutritional value of these potential alternative feedstuffs is necessary while considering their use in swine feeding program. Four tubers (purple sweet potato [PSP], okinawan sweet potato, taro and cassava) and 3 coproducts (okara, wheat millrun [WMR] and barley brewers grain [BBG]) were analyzed for their proximate nutrients, starch, fibers and gross energy (GE) content. Two independent in vitro studies were carried out for tubers and coproducts to determine their nutrients digestibility using a 3-step enzymatic assay (which mimics the digestion occurring in the gastrointestinal tract of swine) with 9 replicates of each sample digested in 3 batches equally. All replicate samples were used to determine in vitro dry matter digestibility (IVDDM) while 2 replicates from each batch were used to determine in vitro GE digestibility (IVDGE). Among tubers, CP content was the highest in taro (8.8%) and the lowest in cassava (3.7%), while CP content among coproducts was the highest in okara (22.7%) and the lowest in WMR (11.8%). Ether extract content among tubers ranged from 1.1% to 2.8%. The GE content among tubers, ranged from 4,134 to 4,334 kcal/kg whereas among coproducts it ranged from 4,270 to 4,794 kcal/kg. Among tubers, IVDDM for PSP was significantly higher (86.8%, P < 0.001) than taro (70.3%). Among coproducts, IVDDM of okara (74.1%) was significantly higher (P < 0.05) than BBG (61.3%). In conclusion, both tubers and coproducts can be used as a partial substitute of conventional energy feedstuffs in swine diets as these are rich in GE and other nutrients and are fairly digestible.

Postprandial portal glucose and lactate fluxes, insulin production, and portal vein-drained viscera oxygen consumption in growing pigs fed a high-fiber diet supplemented with a multi-enzyme cocktail

Information on effects of supplementing fibrous diets with exogenous enzymes on nutrient absorption and energetic demands of visceral organs is scarce. Therefore, this study investigated the effects of supplementing a high-fiber (HF) diet with a multi-enzyme cocktail (MC) on net glucose and lactate portal fluxes, insulin production, and O consumption by the portal-drained viscera (PDV) and whole animal in growing pigs. The MC supplied (analyzed values) 5,397 U of xylanase, 162 U of β-glucanase, and 2,000 U of protease per kg of diet, and guaranteed minimum activities of 1,000 U of α-amylase and 25 U of pectinase per kg of diet. Three isocaloric-nitrogenous diets based on corn and soybean meal with 0% (control) or 30% distillers' dried grains with solubles (DDGS; 1:1 corn and wheat mixture; HF) and HF supplemented with MC (HF + MC) were used. Five gilts (initial BW = 22.8 ± 1.6 kg) fitted with permanent catheters in the portal vein and carotid artery (for blood sampling), and ileal vein (to infuse para-amino hippuric acid to measure blood flow rate) were fed the 3 diets at 4% BW once daily at 0900 h for 7 d in a replicated 3 × 3 Latin square design. On d 7, pigs were placed in an open-circuit indirect calorimeter to measure whole-animal O consumption and sample blood for 7 h postprandial. Net glucose and insulin production were calculated from portal-arterial differences × portal blood flow, and PDV O consumption was calculated as arterial-portal O differences × portal blood flow. Diet had no effect on postprandial whole-animal O consumption, flow rate, and lactate flux. In addition, diet had no effect on overall mean postprandial PDV O consumption. Pigs fed control had greater ( < 0.05) portal insulin and glucose fluxes, from 90 to 300 min and net glucose flux from 90 to 240 min postprandial. However, pigs fed control and HF + MC had similar net glucose flux, which was greater ( < 0.05) than in pigs fed the HF diet. In conclusion, diets did not affect the energetic demand of the PDV but adding MC to the HF diet improved postprandial net glucose portal flux in growing pigs.

Postprandial portal fluxes of essential amino acids, volatile fatty acids, and urea-nitrogen in growing pigs fed a high-fiber diet supplemented with a multi-enzyme cocktail

The present study investigated the effects of adding a multi-enzyme cocktail (MC) to a high-fiber diet on net portal-drained viscera (PDV) fluxes of essential AA (EAA), volatile fatty acids (VFA), and blood urea-N (BUN) in growing pigs. Five female pigs (22.8 ± 1.6 kg BW), with catheters in the portal vein, ileal vein, and carotid artery, were fed 3 isocaloric-nitrogenous diets at 4% of their BW once daily at 0900 h for 7 d in a replicated 3 × 3 Latin square design. The diets contained corn and soybean meal with 0% (control) or 30% distillers' dried grains with solubles (DDGS; HF) produced from a 1:1 mixture of wheat and corn. The third diet was supplemented with MC in addition to the 30% DDGS (HF + MC). The MC supplied (analyzed values) 5,397 U of xylanase, 162 U of β-glucanase, and 2,000 U of protease and guaranteed minimum activities of 1,000 U of α-amylase and 25 U of pectinase per kg of diet. On d 7, para-amino hippuric acid was infused into the ileal vein (to measure flow rate), and blood was sampled from the portal vein and carotid artery for 7 h after feeding to assay EAA, urea-N, and VFA. Portal absorption of nutrients was derived by multiplying the porto-arterial plasma concentration differences by portal vein blood flow. Diet had no effect on postprandial portal vein plasma flow rate and net BUN flux, but portal BUN tended to be lower ( = 0.070) and arterial BUN was lower ( 0.05) over the 7 h in pigs fed control. Postprandial portal Arg, Ile, Leu, Trp, and Val or net fluxes were lower ( 0.05) in HF-fed pigs from 30 to 240 min than control-fed pigs and MC supplementation tended (0.05 ≤ ≤ 0.10) to or improved ( 0.05) portal appearances of those AA, but not their fluxes. Control-fed pigs had higher ( 0.05) net portal fluxes of most EAA and pigs fed HF + MC had higher ( 0.05) Lys, and similar Met and Phe net portal fluxes were compared with control-fed pigs. Portal VFA was not affected by diet. However, total portal VFA flux was lower ( 0.05) in the HF-fed pigs than in the control pigs. The MC supplementation improved the total portal VFA flux, although it did not improve arterial VFA concentration relative to the HF diet. In conclusion, supplementing the HF diet with MC improved net portal appearance of some EAA and fluxes of total VFA, whereas fluxes of EAA did not change. The HF diet increased EAA demand by the PDV, but MC addition was not able to reduce this demand.

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

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

Effect of supplementing a fibrous diet with a xylanase and β-glucanase blend on growth performance, intestinal glucose uptake, and transport-associated gene expression in growing pigs

The present study evaluated supplemental carbohydrase effect on performance, intestinal nutrient uptake, and transporter mRNA expressions in growing pigs offered a high-fiber diet manufactured with distillers dried grains with solubles (DDGS). Twenty-four pigs (22.4 ± 0.7 kg BW) were randomly assigned to 1of 3 nutritionally adequate diets (8 pigs per diet) based on corn and soybean meal (SBM) with either 0 (control) or 30% DDGS (high fiber [HF]). The third diet was supplemented with a xylanase and β-glucanase blend (XB) in addition to the 30% DDGS (HF+XB). Parameters determined were ADFI, ADG, G:F, plasma glucose and plasma urea nitrogen (PUN) concentrations, jejunal tissue electrophysiological properties, and mRNA expressions of the sodium-dependent glucose transport 1 (SGLT1) and cationic AA transporter, bo,+AT, in the jejunal and ileal tissues. In addition, mRNA expressions of the short-chain fatty acid transporters, monocarboxylate transporter 1 (MCT1) and sodium-coupled monocarboxylate transporter, and mucin genes were quantified in the ileum. Feed intake, plasma glucose, and jejunal tissue electrophysiological properties were not affected (P > 0.05) by diet. However, control-fed pigs had superior growth rate and feed efficiency and higher PUN (P < 0.05) than HF- and HF+XB-fed pigs. The HF diet increased (P < 0.05) SGLT1 mRNA expression in the jejunum and decreased (P < 0.05) bo,+ mRNA expression in the ileum. The XB supplementation also increased bo,+ mRNA expression in the ileum relative to HF-fed pigs. Additionally, MCT1 mRNA expression was greater (P < 0.05) in the ileum of the HF- and HF+XB-fed pigs. In the present study, XB supplementation influenced nutrient transporter mRNA expression, although it was not accompanied by improved pig performance.