Post-weaning Pigs Research Articles

PSIV-19 Flavors and Sweeteners in Nursery Pig Diets Increased Intake and Reduced Soft Feces in the First Weeks After Weaning

Abstract The stressful events associated with weaning predispose piglets to reduced feed intake, which in concert with immature digestive and immune systems, results in increased incidences of diarrhea and poor performance. Flavors and sweeteners can be used in diets for young pigs as a means of attracting them to dry feed and increase their feed intake and performance after weaning. The objective of this study was to evaluate the effects of dietary inclusion of flavors and sweeteners and their combination on growth performance and post-weaning gut health of nursery pigs. A total of 1,144 weaned pigs (initial BW 6.61 ± 0.2 kg) were used in a randomized complete block design and assigned to one of four dietary treatments, with 11 replicates (pens) of 26 piglets per pen. Dietary treatments were 1) Control: standard 4-phase nursery feeding program; 2) Sweetener: control plus sweetener (0.015%); 3) Flavor: control plus flavoring (0.05%); 4) Combination: control plus sweetener and flavoring. Experimental diets were provided at a budget of 0.9, 3.4, 4.5, and 24 kg/pig in Phase 1, 2, 3, and 4, respectively. A common phase 5 diet was provided ad libitum until d56 after weaning. Feed disappearance and body weight were measured every other week. A pen fecal score assessment was performed at d4, 7, 10, and 14 after weaning. Overall, there were no differences among dietary treatments for growth performance. However, during the first two weeks post-weaning pigs fed diets containing flavors and sweeteners had a greater (P = 0.097) ADFI than control pigs. On d14, pigs fed diets containing flavors and sweeteners had less incidence of soft and watery feces (χ2 < 0.05) compared to control pigs. This study provides evidence that dietary inclusion of flavors and sweeteners has important benefits to the overall health of nursery pigs likely related to feed intake in the period immediately after weaning.

30 The Effect of Creep Feed Composition and Form on Pre- and Post-weaning Growth Performance of Pigs and the Utilization of Low-quality Nursery Diets

Abstract Fifty-six litters standardized to 12 piglets from first-parity sows were used to determine the effects of creep and nursery diet compositions on pre- and post-weaning pig growth performance. At three days of age, litters (initial BW 2.31±0.61kg) were assigned to one of four creep feeding regimens (n=14): [1] commercial creep feed (COM), [2] liquid milk replacer (LMR), [3] pelleted milk replacer (PMR), or [4] no creep feed (NO); creep feeds contained 1.0% brilliant blue as a fecal marker. Fecal swabs were collected every 3±1 days to identify piglets that regularly consumed creep feed. At weaning (18±1 days of age), six pigs per litter that consumed creep feed were placed on either a HIGH- (contained highly digestible animal proteins) or LOW- (contained corn and soybean meal as the main protein sources) quality nursery diet (n = 7) in a three-phase feeding program over 38 days. The LMR disappeared at the greatest rate (37.7 g/pig/d; DM-basis) versus COM and PMR (10.8±1.5 g/pig/d; P < 0.001). Litters that received LMR had the greatest proportion of pigs with blue fecal swabs between study days 4 and 15 (85.0 vs 59.0±0.4%; P < 0.05) and LMR piglets had greater BW at weaning versus all other treatments (6.32, 6.02, 5.92, 5.67±0.14 kg, for LMR, COM, NO, and PMR, respectively; P < 0.001). Over the entire nursery period, pigs that received LOW diets had reduced ADG (399 vs 485±42 g; P < 0.001), ADFI (520 vs 595±37 g; P< 0.001), G:F (0.77 vs 0.82±0.03; P < 0.01), and BW at the end of the nursery period (21.2 vs 24.4±1.6 kg; P < 0.001), with no carryover effects of creep feeding regimen. Providing supplemental nutrition during the suckling period via LMR improved pig body weight at weaning, but did not improve post-weaning growth performance, regardless of nursery diet quality.

Rotavirus group C infections in neonatal and grower pigs in Australia.

Rotavirus infections of neonatal and older pigs are widely reported. Analysis of rotavirus group C prevalence and diversity has not previously been reported for Australian pig farms. Twenty-seven farms with or without diarrhoea present among neonatal or older pigs were enrolled across eastern Australia. Fresh faecal samples were analysed by ELISA for rotavirus and RNA extractions by polyacrylamide gel electrophoresis and RT-PCR for rotavirus. Rotavirus group C samples were genotyped via sequencing. Rotavirus infection was diagnosed in pigs on 10 of 19 farms investigated for neonatal diarrhoea, four with group A and six with group C; also among post-weaned (5- to 11-week-old) diarrhoeic pigs on two farms. Neonatal rotavirus group C infections were exclusively noted in piglets less than 1-week-old, consisting of farm infections with a single VP7 genotype (G5 or G6). Infections in post-weaned pigs were associated with multiple VP7 genotypes (G1, G3). This first report of rotavirus group C infections of Australian pigs suggests they may form a limited population of VP7 genotypes.

Effects of the Administration of Bifidobacterium longum subsp. infantis CECT 7210 and Lactobacillus rhamnosus HN001 and Their Synbiotic Combination With Galacto-Oligosaccharides Against Enterotoxigenic Escherichia coli F4 in an Early Weaned Piglet Model

We evaluated the potential of multi-strain probiotic (Bifidobacterium longum subsp. infantis CECT 7210 and Lactobacillus rhamnosus HN001) with or without galacto-oligosaccharides against enterotoxigenic Escherichia coli (ETEC) F4 infection in post-weaning pigs. Ninety-six piglets were distributed into 32 pens assigned to five treatments: one non-challenged (CTR+) and four challenged: control diet (CTR−), with probiotics (>3 × 1010 CFU/kg body weight each, PRO), prebiotic (5%, PRE), or their combination (SYN). After 1 week, animals were orally inoculated with ETEC F4. Feed intake, weight, and clinical signs were recorded. On days 4 and 8 post-inoculation (PI), one animal per pen was euthanized and samples from blood, digesta, and tissues collected. Microbiological counts, ETEC F4 real-time PCR (qPCR) quantification, fermentation products, serum biomarkers, ileal histomorphometry, and genotype for mucin 4 (MUC4) polymorphism were determined. Animals in the PRO group had similar enterobacteria and coliform numbers to the CTR+ group, and the ETEC F4 prevalence, the number of mitotic cells at day 4 PI, and villus height at day 8 PI were between that observed in the CTR+ and CTR− groups. The PRO group exhibited reduced pig major acute-phase protein (Pig-MAP) levels on day 4 PI. The PRE diet group presented similar reductions in ETEC F4 and Pig-MAP, but there was no effect on microbial groups. The SYN group showed reduced fecal enterobacteria and coliform counts after the adaptation week but, after the inoculation, the SYN group showed lower performance and more animals with high ETEC F4 counts at day 8 PI. SYN treatment modified the colonic fermentation differently depending on the MUC4 polymorphism. These results confirm the potential of the probiotic strains and the prebiotic to fight ETEC F4, but do not show any synergy when administered together, at least in this animal model.

Serum biochemical parameters and amino acids metabolism are altered in piglets by early-weaning and proline and putrescine supplementations.

The study was to investigate the effect of early-weaning stress and proline (Pro) and putrescine (Put) supplementations on serum biochemical parameters and amino acids (AA) metabolism in suckling and post-weaning pigs. Blood and small intestinal mucosa were harvested from suckling piglets at 1, 7, 14, and 21 d of age and piglets on d 1, 3, 5, and 7 after weaning at 14 d of age, as well as from piglets received oral administration of Pro and Put from 1 to 14 d old. In suckling piglets, the serum glucose, albumin and total cholesterol levels were increased (P < 0.05) with increasing age, whereas the serum globulin, urea nitrogen (BUN), alkaline phosphatase (ALP) and aspartate aminotransferase (AST) levels were lowered (P < 0.05). The concentrations of most serum AA and the AA transporters related gene expressions were highest in 7-d-old piglets (P < 0.05), whereas the phosphorylation status of the mammalian target of the rapamycin (mTOR) signaling pathway in the small intestine increased in piglets from 1 to 21 d old (P < 0.05). Weaning at 14 d old increased (P < 0.05) the BUN and triglycerides levels in serum, as well as jejunal solute carrier family 7 member 6 (SLC7A6), ileal SLC36A1 and SLC1A1 mRNA abundances at d 1 or 3 post-weaning. Weaning also inhibited (P < 0.05) the phosphorylation levels of mTOR and its downstream ribosomal protein S6 kinase 1 (S6K1) and 4E-binding protein-1 (4EBP1) in the small intestine of weanling pigs. Oral administration of Put and Pro decreased (P < 0.05) serum ALP levels and increased (P < 0.05) intestinal SLC36A1 and SLC1A1 mRNA abundances and mTOR pathway phosphorylation levels in post-weaning pigs. Pro but not Put treatment enhanced (P < 0.05) serum Pro, arginine (Arg) and glutamine (Gln) concentrations of weaning-pigs. These findings indicated that early-weaning dramatically altered the biochemical blood metabolites, AA profile and intestinal mTOR pathway activity, and Pro and Put supplementations improved the AA metabolism and transportation as well as activated the intestinal mTOR pathway in weanling-pigs. Our study has an important implication for the broad application of Pro and Put in the weaning transition of piglets.

Characterization of Kazachstania slooffiae, a Proposed Commensal in the Porcine Gut.

Kazachstania slooffiae is a fungus commonly isolated from the gastrointestinal tract and feces of post-weaning pigs. Studies have implicated its ability to positively alter piglet gut health through potential symbioses with beneficial bacteria, including Lactobacillus and Prevotella, in providing amino acids as an energy source for microbial and piglet growth, and it has been found to be positively correlated with short-chain fatty acids in the piglet gut. However, basic mycological information remains limited, hampering in vitro studies. In this study, we characterized the growth parameters, biofilm formation ability, susceptibility to antimicrobials, and genetic relatedness of K. slooffiae to other fungal isolates. Optimal fungal growth conditions were determined, no antifungal resistance was found against multiple classes of antifungal drugs (azoles, echinocandins, polyenes, or pyrimidine analogues), and dimorphic growth was observed. K. slooffiae produced biofilms that became more complex in the presence of Lactobacillus acidophilus supernatant, suggesting positive interactions with this bacterium in the gut, while Enterococcus faecalis supernatant decreased density, suggesting an antagonistic interaction. This study characterizes the in vitro growth conditions that are optimal for further studies of K. slooffiae, which is an important step in defining the role and interactions of K. slooffiae in the porcine gut environment.

The Effect of Fermented Kefir as Functional Feed Additive in Post-Weaned Pigs

The control of the immune system of pigs after weaning is important in pig farming because productivity depends on the survival of the post-weaned pigs. Previously, antibiotics would have been administered in the case of infectious diseases to increase the survival rate of post-weaned pigs, but now, the use of antibiotics is strictly restricted in order to prevent other problems such as the occurrence of antibiotic-resistant pathogens. In this study, the effect of fermented kefir as a functional feed additive as a replacement to antibiotics was evaluated in terms of the microbial profile in fecal samples, immunological factors in the blood of pigs, growth performance measured as average daily gain (ADG) and the feed conversion rate (FCR) of post-weaned pigs. In the kefir-treated group, the number of lactic acid bacteria and Bacillus spp. in the fecal samples of the pigs increased with the kefir treatments. Interestingly, the number of coliform groups as opportunistic pathogens was reduced in the fecal samples of pigs treated with kefir. We found out that treatment with kefir enhanced the innate immunity of post-weaned pigs though the reduction of IL-6 as a proinflammatory cytokine and an increase in IgG as an immunoglobulin, enhancing immunological defense against pathogens. Finally, after treatment with kefir, we observed that the ADG of post-weaned pigs increased to 135.6% but FCR decreased to 92.2%. Therefore, this study shows that fermented kefir can be used as a functional feed additive and an antibiotic alternative in order to improve both the innate immune system and growth performance of post-weaned pigs.

Effects of Providing a Liquid Sensory Attractant to Suckling Pigs in Lactation and After Weaning on Post-Weaning Pig Performance

Effects of Providing a Liquid Sensory Attractant to Suckling Pigs in Lactation and After Weaning on Post-Weaning Pig Performance

Effects of Providing Enrichment Cubes to Suckling Pigs in Late Lactation and After Weaning on Post-Weaning Pig Performance

Effects of Providing Enrichment Cubes to Suckling Pigs in Late Lactation and After Weaning on Post-Weaning Pig Performance

Meta-analysis to evaluate the impact of the reduction of dietary crude protein on the gut health of post-weaning pigs

Weaning transition is often associated with the occurrence of the post-weaning diarrhoea syndrome (PWDS). The reduction of dietary crude protein (CP) has been intensively used as a strategy for controlling PWDS. The aim of the present meta-analysis was to report the effect of the reduction of dietary CP on the intestinal parameters related to the gut health, growth and diarrhoea of post-weaning piglets. A literature review of the articles published from 2006 to 2019 produced 48 articles and, of these 26 were selected. Parameters (bacterial metabolites, pH, microbiota diversity, intestinal morphology, inflammation markers, growth, faecal score) were extracted, expressed as a percentage of the control diet and analysed using a general linear model which included the study, reduction in points of dietary CP, and the ratio of digestible Lysine and dietary CP (dLys/CP) as factors. The reduction of dietary CP decreased ammonia (p < .0001), pH (p = .039), total short-chain fatty acids (SCFAs) (p = .027), biogenic amines including cadaverine (p = .034) and putrescine (p = .030) and the expression of TLR4 (p < .0001) in the intestine and also reduced the faecal score (p = .002). The dLys/CP ratio increased the level of Lactobacilli and the expression of TLR4 (p < .05), and tended to increase acetic acid (p < .1). Crypt depth, villus height, microbiota diversity and growth remained unchanged. In conclusion, this study confirmed that a reduction of dietary CP could reduce bacterial protein fermentation and the production of potentially toxic metabolites. In turn, this could result in lower intestinal inflammation and a decreased risk of diarrhoea in weaning piglets. Highlights Reducing the dietary crude protein can decrease the fermentation of undigested dietary protein, especially in the large intestine. Lowering undigested dietary protein results in a reduction of the intestinal pH and potentially toxic metabolites, including ammonia and amines. Diets with lower crude protein reduce inflammation of the intestinal mucosa and the post-weaning diarrhoea of piglets without compromising performance.

Effects of Providing a Sensory Attractant Powder to Suckling Pigs in Late Lactation and After Weaning on Post-Weaning Pig Performance

Effects of Providing a Sensory Attractant Powder to Suckling Pigs in Late Lactation and After Weaning on Post-Weaning Pig Performance

Indications and patterns of antimicrobial use in pig farms in the southern Kyushu, Japan: large amounts of tetracyclines used to treat respiratory disease in post-weaning and fattening pigs.

In Japan, reducing the use of antimicrobials in pig production is a significant issue. However, there are no published reports concerning porcine disease treatment, as related to the age of the pigs and the indications (e.g., organ system) in Japan. In this study, we analyzed the prescription records of 17 farrow-to-finish farms from 2014 to 2018 in southern Kyushu, Japan. The farms’ antimicrobial usage was calculated as the active ingredient per population correction unit (PCU) or the number of treated pigs per PCU using the defined daily dose. All data were analyzed according to the indications and production stages (sows, suckling pigs, post-weaning pigs, and fattening pigs). In terms of active ingredients/PCU, tetracyclines were the most commonly used (43.2–59.3%), and the largest amounts of antimicrobials administered through feeds were for treating the respiratory organs of fattening pigs. In terms of the number of treated pigs/PCU, tetracyclines were most frequently used (16.3–31.1%), and a high frequency of antimicrobials administered through feeds was used for the treatment of respiratory organs in post-weaning pigs. In this study, it was confirmed that tetracyclines were used frequently as a herd treatment for respiratory diseases in post-weaning and fattening pigs in southern Kyushu, Japan. The findings suggest that it is necessary to improve the treatment and prevention of respiratory diseases in post-weaning and fattening pigs in order to reduce the frequencies of antimicrobial treatments.

Electrically Energized Comfort Heating System Based on Electric Film Heaters and intended for Post-Weaned Pigs

The reported paper summarizes outcomes of the thesis “Electrically energized comfort heating system intended for pre-nursery pigs kept in an unheated sow house” [2]. This alternative method of keeping warm pre-nursery pigs has been proven to be efficient both in the pilot phase and in pilot batch production. The further research aimed at the application of this system to the keeping warm pre-weaned pigs. The paper describes and presents a calculation procedure for parameters of a comfort heating system based on film heaters and intended for pre-weaned pigs.

289 Effects of supranutritional levels of dietary zinc oxide on zinc, copper, and iron metabolism in post-weaned pigs

Abstract This study evaluated the impact of supranutritional levels of dietary zinc oxide (ZnO) on zinc (Zn), copper (Cu), and iron (Fe) homeostasis in post-weaned pigs. One hundred twenty piglets were selected at d14 of age (5.65 ± 0.68 kg). At weaning (d21), they were fed a basal post-weaning diet (without antibiotics) supplemented (n = 40/treatment) with 100 mg/kg (low; LZn), 1000 mg/kg (medium; MZn) or 3000 mg/kg (high; HZn) of ZnO until d42. Dietary levels of Cu (130 mg/kg) and Fe (260 mg/kg) remained constant throughout the experimental period. Piglets were sacrificed at d21, d23, d35, and d42 of age (n = 10/treatment/d) for samples collection. Serum concentrations and total liver content of Zn and Cu were not different among treatments on d21 and d23 (P ≥ 0.10). For Zn, treatment effects were detected at d35 and d42 (P &amp;lt; 0.01) on both serum concentration and total Zn content in liver. For both parameters, values were greatest for HZn, intermediary for MZn, and lowest for LZn irrespective of ages in the two periods. For Cu, treatment effects were detected at d35 and d42 (P &amp;lt; 0.01) on both serum concentration and total Cu content in liver. For both parameters, values were greatest for LZn and MZn and lowest for HZn irrespective of ages. For Fe, no treatment effect was detected either on whole blood Fe concentrations (P = 0.81) or hemoglobin levels (P = 0.76). However, for total Fe content in liver, treatment effects were detected (P &amp;lt; 0.01). Values were greatest for LZn and lowest for HZn at d35 and d42 whereas for MZn they were intermediary at d35 and similar to LZn at d42 (P ≤ 0.01). In conclusion, supranutritional levels of dietary ZnO fed to piglets during 3 weeks post-weaning significantly impacted Zn, Cu, and Fe homeostasis. These results emphasise the potential risk of Cu deficiency as well as impairment in building body Fe reserves under long-term supranutritional supplementation of ZnO.

PSVIII-16 The effects of adding two organic acid blends with or without high levels of zinc or copper, on post-weaning pig performance

Abstract A subset of 720 weaned pigs (6.44 ± 0.1 kg, PIC genetics, approximately 21-d of age) were used in a 42-d trial with a 2x3 factorial design evaluating the effects of adding organic acid (OA) blends [factor 1 = no organic acid (NO), Acid Pak 1 (AP1), Acid Pak 2 (AP2)] to diets with or without higher levels of Zn or Cu [factor 2 = +/-PZC] on pig performance. Pigs were allotted 10 pigs/pen to 12 weight blocks and randomly assigned the six dietary treatments. The +PZC diets contained 3000 ppm Zn (d 0-7), 2000 ppm Zn (d 8-21), and 250 ppm Cu (d 21-42) and -PZC diets contained 95 ppm Zn and 20 ppm Cu (d 0-42). The AP1 and AP2 diets used 0.9% of 2 acid premixes (d 0-21), and 0.45% of the premixes (day 22-42). AP1 provided 0.5% benzoic acid, 0.07% sodium butyrate, and 0.025% phosphoric acid (day 0-21) and half those levels (day 22-42). AP2 included the same acids as AP1 but at half the rate and combined with 7 other organic acids and carvacrol. From d 0-21, ADG, ADFI, and G:F were improved (P&amp;lt; 0.01) by +PZC compared to -PZC and by AP1 or AP2 compared to NO (P&amp;lt; 0.02). Overall (d 0-42), ADG and G:F were improved (P&amp;lt; 0.01) by +PZC compared to -PZC and by AP1 or AP2 compared to NO (P&amp;lt; .010). Data from this trial indicate that performance was improved by the addition of both OA and PZC. However, pigs fed OA and -PZC performed similarly to those fed NO and +PZC in the post-weaning period. In summary, regardless of the acid combination, organic acid supplementation has the potential to improve growth performance in weaned pigs.

PSIII-2 Considering a large creep pellet as a means to improve suckling and early weaned pig performance

Abstract This study evaluated the benefit of creep feeding with large pellets (10mm diameter, Masterfeeds, London, ON, Canada) on pre- and post-weaning pig performance. Litters from two farrowing groups were assigned to one of 2 treatments: Control (no creep n= 25 litters) and Creep (large creep pellets n = 24) during the suckling phase. Pellets were provided beginning 7 d after the first sow farrowed within a group until weaning at 21 d. Pellets were placed in shallow plastic feeders three times/day (100-150 g at a time as needed) to ensure access to fresh feed. Creep pellets contained 2500 ppm zinc and ferric oxide-dyed biscuit crumbles were added at 5% inclusion in Phase 1 nursery diet. Therefore, fecal zinc concentration at 2 to 3d prior to weaning and red fecal coloration 2 to 4d after weaning were used to identify “eaters” from “non-eaters”. Pigs were weaned at 21 ± 2 d into pens based on suckling treatment. Data were analyzed as a randomized complete block with the sows as a random effect (PROC MIXED, SAS Inst., Inc., Cary, NC). Post-weaning fecal swabs data were analyzed by frequency test using the PROC FREQ procedure in SAS. There was no difference in pig weight prior to creep pellets. At weaning, Control pigs were heavier due to greater daily gain (P &amp;lt; 0.01; Table 1) than Creep pigs. However, there was no difference in d34 BW due to greater (P &amp;lt; 0.05) daily gain of Creep pigs in the post-weaning period. A greater proportion of Creep pigs were identified as “eaters” on d2 post-weaning (43 vs 33%, □ 2 = 0.004; Figure 1). Lighter weight at weaning in Creep pigs may be due to temporary distraction from suckling; however, exposure to large creep feed pellets pre-weaning improved pig feed intake and growth post-weaning.

Parenterally Administered Porcine Epidemic Diarrhea Virus-Like Particle-Based Vaccine Formulated with CCL25/28 Chemokines Induces Systemic and Mucosal Immune Protectivity in Pigs.

Generation of a safe, economical, and effective vaccine capable of inducing mucosal immunity is critical for the development of vaccines against enteric viral diseases. In the current study, virus-like particles (VLPs) containing the spike (S), membrane (M), and envelope (E) structural proteins of porcine epidemic diarrhea virus (PEDV) expressed by the novel polycistronic baculovirus expression vector were generated. The immunogenicity and protective efficacy of the PEDV VLPs formulated with or without mucosal adjuvants of CCL25 and CCL28 (CCL25/28) were evaluated in post-weaning pigs. While pigs intramuscularly immunized with VLPs alone were capable of eliciting systemic anti-PEDV S-specific IgG and cellular immunity, co-administration of PEDV VLPs with CCL25/28 could further modulate the immune responses by enhancing systemic anti-PEDV S-specific IgG, mucosal IgA, and cellular immunity. Upon challenge with PEDV, both VLP-immunized groups showed milder clinical signs with reduced fecal viral shedding as compared to the control group. Furthermore, pigs immunized with VLPs adjuvanted with CCL25/28 showed superior immune protection against PEDV. Our results suggest that VLPs formulated with CCL25/28 may serve as a potential PEDV vaccine candidate and the same strategy may serve as a platform for the development of other enteric viral vaccines.

Cyberlindnera jadinii Yeast as a Protein Source for Weaned Piglets-Impact on Immune Response and Gut Microbiota.

Supplying novel feed ingredients for pig production is crucial to enhance food security and decrease the environmental impact of meat production. Several studies have focused on evaluating the beneficial health effects of yeast in pigs. However, its use as a protein source has been partially addressed. Previously, we have shown that yeast at high inclusion levels maintains growth performance and digestibility, while nutrient digestibility, intestinal villi height and fecal consistency were improved. The present study combined microbiome, short-chain fatty acid, and immune parameter analysis to investigate the effect of high inclusion of yeast in diets for post-weaning piglets. Our results showed that yeast did not have a significant impact on the hematological or biochemical parameters in blood. The different immune cell subpopulations isolated from blood and distal jejunal lymph nodes (DJLN) were analyzed by flow cytometry and showed that yeast diet induced an increased number of the subtype of leukocytes CD45+/CD3–/CD8+, a special type of Natural Killer (NK) cells. Also, a very mild to moderate infiltration of neutrophilic granulocytes and lower IgA level were observed in the colon of yeast fed piglets. The microbiome profiling in different compartments of the gastrointestinal tract of piglets was performed using 16S rRNA metabarcoding. The results showed that 40% replacement of dietary protein had a statistically significant effect on the microbial communities in cecum and colon, while the microbial population in ileum and jejunum were not affected. Analysis of predicted microbial metabolic pathways analysis revealed significant upregulation of short-chain fatty acids, ether lipid metabolisms, secondary bile acids, and several other important biosynthesis pathways in cecum and colon of pigs fed yeast. In conclusion, the results showed that diet containing 40% of yeast protein positively shaped microbial community in the large intestine and increased the number of a specific subpopulation of NK cells in the DJLN. These results showed that yeast modulates the microbiome and decreases the secretion of IgA in the colon of post-weaning pigs.

Analysis of Gastrointestinal Responses Revealed Both Shared and Specific Targets of Zinc Oxide and Carbadox in Weaned Pigs.

Antibiotics and pharmacological zinc supplementation were commonly used as growth promoters for several decades in the swine industry before being limited because of public health and environmental concerns. Further, the physiological and metabolic responses associated with their growth promotion effects are unclear. To characterize these responses induced by pharmacological zinc supplementation (2500 mg/kg) and carbadox (55 mg/kg), 192 post-weaning pigs were fed basal and test diets for 43 days. Compared with basal, pharmacological zinc and carbadox independently improved growth performance. Pharmacological zinc increased gastric mucosa thickness compared with basal zinc, while carbadox increased intestinal villus:crypt ratio compared with non-carbadox. Pharmacological zinc and carbadox independently reduced interleukin (IL)-1β concentration compared with basal zinc and non-carbadox. Pharmacological zinc increased IL-1RA:IL-1 ratio by 42% compared with basal zinc, while carbadox tended to increase the IL-10 and IL10:IL-12 ratio compared with non-carbadox. Carbadox increased fecal concentrations of histidine and lysine compared with non-carbadox. The independent effect of pharmacological zinc and carbadox on morphology and nutrient metabolism, and their shared effect on immunity may contribute to the additive effect on growth promotion. These results further confirmed the concept that growth promotion is multifactorial intervention. Therefore, elucidating growth-promoting effects and searching for alternatives should include wide-spectrum evaluation.

Prevalence and Characterization of Virulence Genes in &lt;i&gt;Escherichia coli&lt;/i&gt; Isolated from Diarrheic Piglets in Korea

Enterotoxigenic Escherichia coli is one of the major causative infectious agents of diarrhea in newborn and post-weaning pigs and leads to a large economic loss worldwide. However, there is limited information on the distribution and characterization of virulence genes in E. coli isolated from diarrheic piglets, which also applies to the current status of pig farms in Korea. To investigate the prevalence and characterization of virulence genes in E. coli related to diarrhea in piglets, the rectal swab samples of diarrheic piglets (aged 2 d to 6 w) were collected from 163 farms between 2013 and 2016. Five to 10 individual swab samples from the same farm were pooled and cultured on MacConkey agar plates, and E. coli were identified using the API 32E system. Three sets of multiplex PCRs were used to detect 13 E. coli virulence genes. As a result, a total of 172 E. coli isolates encoding one or more of the virulence genes were identified. Among them, the prevalence of individual virulence gene was as follows, (1) fimbrial adhesins (43.0%): F4 (16.9%), F5 (4.1%), F6 (1.7%), F18 (21.5%), and F41 (3.5%); (2) toxins (90.1%): LT (19.2%), STa (20.9%), STb (25.6%), Stx2e (15.1%), EAST1 (48.3%); and (3) non-fimbrial adhesin (19.6%): EAE (14.0%), AIDA-1 (11.6%) and PAA (8.7%), respectively. Taken together, various pathotypes and virotypes of E. coli were identified in diarrheic piglets. These results suggest a broad array of virulence genes is associated with coliform diarrhea in piglets in Korea.