Post-weaning Piglets Research Articles

A Double Lysis Method for Animal Rotavirus RNA Extraction From Stool Samples.

Globally, porcine rotavirus is a leading cause of gastroenteritis in nursing and post-weaning piglets, as well as adult pigs. Between February 2015 and June 2016, 156 fecal samples were collected from pigs in the Northeastern part of Accra, Ghana, and screened for Group A rotavirus using the ProflowTM Kit. Here, we describe different extraction methods that were employed to recover high-quality RNA for downstream analysis, with emphasis on a novel hybrid extraction method. The hybrid approach with a kit and manual extraction method led to a 10-fold greater RNA yield versus the kit-based method alone. The new extraction method gave an average purity ratio (A260/A280) of 1.8, which was also significantly higher than that obtained solely from the manual or kit-based extraction methods. Our novel hybrid approach will be useful in the extraction of rotavirus from animal fecal samples, thus improving the yield of RNA for downstream analysis. © 2024 Wiley Periodicals LLC. Basic Protocol: Hybrid 2: A double lysis method for RNA extraction from animal stool samples Support Protocol 1: The GenElute extraction method Support Protocol 2: Hybrid 1 extraction method.

383 Performance of piglets in response to graded dietary supplementation of sulfur amino acids using either hydroxy-methionine or DL-Methionine during the post-weaning period

Abstract Providing piglets with their precise nutritional need is critical during the stressful post-weaning period. Methionine (Met), a sulfur-containing amino acid, has a crucial role in piglet growth and health. Stressful conditions may increase Met demand due to its involvement in maintaining redox balance via downstream metabolites such as glutathione. There are different sources of supplementary Met for pigs such as DL-methionine (DL-Met) and hydroxy-methionine. The latter comes mostly as an acidic liquid form (OH-Met) and to a lesser degree as a powder calcium-salt (OH-Met-Ca). This study investigates the effect of graded levels of dietary total sulfur amino acids (TSAA) by supplementing different sources of Met on the performance and capacity of post-weaning piglets to respond to stress. Two experiments were performed. In experiment 1, post-weaning piglets [n = 90; 28 d of age; body weight (BW) = 9.13 ± 0.65 kg] were fed with either DL-Met or OH-Met-Ca to provide 80%, 100%, and 125% TSAA recommendations of NRC and performance parameters were measured for 41 d. Treatments were replicated nine times, and blocking was done according to initial BW. For experiment 2, 720 post-weaning piglets (n = 720; 28 d of age; BW = 6.84 ± 1.07 kg) from three consecutive breeding batches were fed with either DL-Met, OH-Met, or OH-Met-Ca at or above (100% or 125%) TSAA requirements of FEDNA. Performance parameters and oxidative status through various plasma indicators were measured. Treatments were replicated 12 times. Data from both experiments were analyzed separately using a mixed effect model with Met source and level as fixed effects (and their interaction in experiment 2) and blocks and batch as random effects for experiments 1 and 2, respectively. In experiment 1, piglets fed 80% of TSAA requirement showed the least average daily weight gain, while those fed OH-Met-Ca at 100% or DL-Met at 125% requirement had the greatest BW gain among the treatments (P < 0.01). Feed conversion ratio was best for piglets fed with OH-Met-Ca at 100% requirement, while animals fed with 80% requirement were the least efficient (P = 0.04). Contrasts showed no differences between Met sources (P ≥ 0.51) and level of TSAA (P ≥ 0.56) for any of the parameters. Meanwhile in experiment 2, there were no interactions between Met source and TSAA level (P > 0.10). The Met source did not affect any parameter (P ≥ 0.14). However, there was a significant decrease in daily feed intake when piglets were fed above requirements (P = 0.02), and a significant increase in the concentration of plasma glutathione peroxidase when piglets were fed at TSAA requirements (P < 0.05). These results suggest that post-weaning piglet performance and oxidative status can be sustained regardless of the Met source tested. Feeding healthy and unchallenged piglets with excess dietary Met may not bring extra benefits.

447 Ex-food4feed: Keeping nutrients in the food chain - Sponsored by EAAP

Abstract The growing world population and rising income in developing countries create more demand for animal products. However, natural resources such as land, water, and nutrients are not boundless. As a consequence, competition of resources in food and feed production is an issue to be confronted with. One promising solution is relocating food losses into animal feeding, propelling the course of sustainability and circular economy in the livestock sector. Given this scenario, former food products (FFPs) represent great opportunities. Instead of ending up in landfill or compost, a better destination for FFPs is to be used as feedstuffs to replace traditional ingredients. FFPs are foodstuffs not accepted by the human market but have several advantages enabling them to enter swine feeding programs. FFPs are mainly composed of processed and ready-to-eat food products such as snacks and bakery goods. Thanks to industrial processing and their product type nature, FFPs are rich in easily digestible starch, simple sugars, fat, and energy contents comparable with cereal grains. Based on their nutritional features, these materials are extremely rich in carbohydrates, free sugars and, depending on their origin, also in fats. In addition, FFPs are often characterized by a high degree of processing including technological and heat treatments which can affect not only the availability of nutrients and the kinetics of digestion, but also gastro-intestinal health and animal response. On fresh matter basis, FFPs can substitute conventional feed ingredients up to 30 % in the diets of pigs. Starting from post-weaning piglets, FFP-based diet is able to maintain piglet growth without substantial effects on hindgut microbiota. In growing-finishing pigs, FFP-based diets at a 30 % inclusion level support growth performance of pigs without altering their nutrient and energy deposition efficiency, live body and carcass composition, and general meat quality traits. When considering liver proteome and plasma peptidome of pigs fed such diets, minor modulation occurs. To sum up, while maintaining the performance and wellbeing of pigs, the use of FFPs up to 30 % to replace classic feedstuffs represents a great potential in: i) mitigating food-feed competition, ii) re-distributing valuable food losses to livestock sector to produce animal protein, and iii) reducing environmental footprints resulting from animal production. All these aspects point out important concepts under the principles of circular economy and resilience enhancement in livestock farming, namely, making the most of resources to build a regenerative food system.

The Effects of Fermented Cauliflower Residue Feed on the Diarrhea Rate, Intestinal Morphology, Immune Indicators, and Intestinal Flora of Weaned Piglets

This study investigated the effects of incorporating fermented feed into the post-weaning piglet diet, with a focus on its impact on the growth, health, serum markers, immune function, diarrhea rate, and microbial community of post-weaning piglets. Forty-two post-weaning piglets (Duroc × [Landrace × Yorkshire], castrated male), with good health and similar weight (11.40 ± 1.36 kg) at 40 days of age, were randomly assigned to two groups. Throughout the trial, one group received a standard diet (control group) while the other one was given a diet supplemented with fermented feed (experimental group), respectively. The findings revealed that compared to the control group, the post-weaning piglets fed with fermented feed showed increased daily weight gain. The fermented feed also led to an increase in the height of villi in the duodenum or jejunum of post-weaning piglets (p < 0.05), accompanied by an improved ratio of villus height to crypt depth in the experimental group (p < 0.05). Furthermore, the fermented feed enhanced the richness and diversity of the intestinal microbial community in post-weaning piglets (p < 0.05), particularly increasing the relative abundance of Lactobacillaceae and Bifidobacteriaceae. These findings demonstrate that incorporating the fermented feed into the diet can reduce the diarrhea rate, improve growth performance, enhance immune function, and promote intestinal development in post-weaning piglets.

466 Dietary microalgae (Chlorella vulgaris) may stimulate GSH-antioxidant system in response to increased deposition of muscle omega-3 polyunsaturated fatty acids in post-weaning piglets

466 Dietary microalgae (<i>Chlorella vulgaris</i>) may stimulate GSH-antioxidant system in response to increased deposition of muscle omega-3 polyunsaturated fatty acids in post-weaning piglets

The Vehicle of Administration and Prandial State May Reduce the Spectrum of Oral Broad-Spectrum Antibiotics (Oxytetracycline, Fosfomycin and Amoxicillin) Administered to Piglets: A Pharmacokinetic/Pharmacodynamic Approach.

The objective of this study was to assess the impact of the vehicle of administration and the prandial state of post weaning piglets on the indices of therapeutic efficacy for different broad-spectrum antibiotic/pathogen combinations. Pharmacokinetic data were retrieved from previous studies, in which we orally administered oxytetracycline (OTC), fosfomycin (FOS), or amoxicillin (AMX) according to the following treatments: dissolved in soft water to fasted or non-fasted piglets, dissolved in hard water to fasted or non-fasted piglets, and mixed with feed. Minimum inhibitory concentration (MIC) values for susceptible strains of bacteria causing swine diseases were obtained from the database of European Committee on Antimicrobial Susceptibility Testing (EUCAST) for each antibiotic. Pharmacokinetic/pharmacodynamic (PK/PD) indices of therapeutic efficacy-drug exposure over the dosing interval (fAUC/MIC) for OTC and FOS; time that free drug concentration remains above MIC (%fT>MIC) for AMX-were calculated for each antibiotic/pathogen combination under each treatment. After all OTC and in-feed FOS and AMX treatments, the indices of therapeutic efficacy were below the target value for all the study microorganisms. When FOS or AMX were delivered dissolved in soft or hard water, the indices were above the target value over which therapeutic efficacy would be expected for Escherichia coli treated with FOS and, Glaesserella parasuis, Pasteurella multocida, and Actinobacillus pleuropneumoniae treated with AMX. The prandial state of piglets showed no influence on the indices of therapeutic efficacy. Pharmacokinetic profiles of broad-spectrum antibiotics, specifically the ability to achieve target concentrations, may be largely reduced due to drug interactions with components present in feed or water resulting in a discrepancy with PK/PD principles of prudent and responsible use of antibiotics.

Macrogenomic and Metabolomic Analyses Reveal Mechanisms of Gut Microbiota and Microbial Metabolites in Diarrhea of Weaned Piglets.

Recent studies have shown a correlation between piglet diarrhea and the gut microbiota. However, the precise mechanism by which intestinal microorganisms and their metabolites influence diarrhea in weaned piglets remains unclear. This study explored differences in the gut microbiota and associated metabolites between healthy and diarrheic-weaned piglets using macrogenomic and metabolomic analyses. The histomorphological results showed that diarrheic piglets had shorter jejunal and ileal villi, some of which were shed, compared to healthy piglets. Substantial differences in gut microbial diversity and metabolites were also observed, with Bacteroidaceae bacterium and Caudoviricetes being the main differential organisms that were strongly correlated with host status. Microbial functions, mainly the metabolism of carbohydrates, glycans, lipids, and amino acids, as well as related enzyme activities, were substantially different. The major differential metabolites were carnosine, pantothenic acid (vitamin B5), pyridoxal, methylimidazoleacetic acid, indole-3-acetaldehyde, and 5-hydroxyindoleacetic acid. These metabolites were enriched in beta-alanine, histidine, tryptophan, and vitamin B6 metabolism, and in the pantothenate and CoA biosynthesis pathways. Combined macrogenomic and metabolomic analyses revealed that carnosine, vitamin B5, and pyridoxal were negatively correlated with Caudoviricetes; methylimidazoleacetic acid, indole-3-acetaldehyde, and 5-hydroxyindoleacetic acid were positively correlated with Caudoviricetes. Whereas carnosine and vitamin B5 were positively correlated with Bacteroidaceae bacterium, 5-hydroxyindoleacetic acid was negatively correlated. The decreased abundance of Bacteroidaceae bacterium and the increased abundance of Caudoviricetes and related metabolites likely contribute to post-weaning diarrhea in piglets. Therefore, the abundance of Bacteroidaceae bacterium and Caudoviricetes can likely serve as potential markers for identifying and preventing diarrhea in post-weaning piglets.

47. Effect of low calcium diet supplemented with microbial phytase in post-weaning piglets

47. Effect of low calcium diet supplemented with microbial phytase in post-weaning piglets

40. An encapsulated sodium butyrate derived from fermentation improves the performance of post-weaning piglets

40. An encapsulated sodium butyrate derived from fermentation improves the performance of post-weaning piglets

Yeast mixture supplementation modulates faecal microbiota and ileum morphology of weaning pigs

Different yeast strains benefit postweaning piglets by promoting intestinal health. The objective of this study was to investigate the effect of a yeast mixture containing Kluyveromyces marxianus fragilis, Pichia guilliermondii, and Saccharomyces cerevisiae (Vetoquinol italia s.r.l., Italy) on gut health parameters and growth performance traits of weaned piglets. Forty-eight postweaning castrated male piglets (27 ± 1.7 days, 7.19 ± 0.54 kg) were randomly allocated to two homogeneous experimental groups and involved in a 28-day trial. Both the groups received a basal diet with (yeast mixture, YM) or without (control, CTR) the inclusion of 0.8% yeast mixture during weeks 1 and 2, and 0.6% during weeks 3 and 4. Individual BW and box feed intake were determined on days 0, 14, and 28, and average daily gain and Gain:Feed ratio were subsequently calculated for each administration period (0–14, 14–28). Individual faecal samples were collected for microbiota analysis on days 4, 14, 21, and 28, and faecal score was evaluated on the same days. At the end of the trial, 12 piglets for each group were sacrificed, and ileal tissue was sampled for morphological analysis and the evaluation of mucins profile, using Alcian-Blue/Periodic Acid-Shiff (PAS) staining. On ileum samples, dividing and differentiated epithelial cells were also identified using proliferating cell nuclear antigen and alkaline phosphatase expression, respectively. Differences in the means between the experimental groups were determined by ANOVA, while the metataxonomics analyses were performed by sequencing for V3 and V4 hypervariable regions of the 16S rRNA gene. Growth performance traits were not different among the two experimental groups when considering the whole trial period, while treated animals showed increased faecal consistency on weeks 1 and 4 (P = 0.036 and 0.021, respectively). Yeast mixture administration increased the abundance of Bifidobacterium (P = 0.006) and Coprococcus 2 (P = 0.015), and decreased Clostridium Sensu Stricto 1 (P = 0.019) at all the considered timepoints. Ileum villous height, villous width, and crypt depth were significantly increased by yeast mixture supplementation (P = 0.019; P = 0.013; P = 0.036, respectively), while no differences were observed for the villous:crypt ratio among the groups. The mucin profile showed no differences among experimental groups for acid and neutral glycoconjugates. However, a higher presence of PAS-positive mucins was highlighted in the villi of YM piglets (P < 0.001) compared to CTR. Overall, the administration of a yeast mixture to postweaning piglets showed positive effects on gut health when compared to piglets not receiving the tested product, improving beneficial genera and intestinal morphology.

Nutraceutical Additives Modulate Microbiota and Gut Health in Post-Weaned Piglets.

Due to the challenge of weaning pigs and the need to reduce the use of antimicrobials in animal feed, there is a growing need to look for nutraceutical alternatives to reduce the adverse effects of the post-weaning period. We evaluate the effect of different feed nutraceutical additives on the microbial communities, gut health biomarkers, and productivity of pigs during the post-weaning period. The study involved 240 piglets weaned on the 21st day of age and randomized to six different diets: D1-BD commercial standard feed, D2-AGP: D1 + 150 ppm zinc bacitracin, D3-MD: D1 + 550 ppm maltodextrin, D4-FOS: D1 + 300 ppm fructo-oligosaccharides, D5-EO: D1 + 70 ppm Lippia origanoides essential oil, and D6-SH: D1 + 750 ppm sodium humate. On day 30 post-weaning, zootechnical parameters were evaluated, and jejunal samples were taken to obtain morphometric variables, expression of barrier and enzymatic proteins, and analysis of microbial communities. Animals fed D4-FOS and D5-EO had the lowest feed conversion ratio and higher expression of barrier and enzymatic proteins compared to D1-BD, D2-AGP, and D3-MD. The use of the additives modified the gut microbial communities of the piglets. In conclusion, fructo-oligosaccharides and Lippia origanoides essential oil were the best alternatives to zinc bacitracin as antibiotic growth promoters.

The Effect of Vitamins on the Immune Systems of Pigs.

In modern pig farming, there are many environmental, physiological or social stresses that weaken the immune response and increase susceptibility to disease. Nutritional management has a significant impact on the efficiency of the immune system in pigs. Among the various nutrients, vitamins have been shown to have specific effects on immune system activity. However, the needs of modern genetic types are not met by the dietary recommendations for vitamins in pig diets. The present study therefore summarises the data on dietary integration with supranutritional doses of vitamins in gestating and lactating sows and post-weaning piglets in terms of the immune response. The present data highlight that high doses of dietary vitamins are an effective way to improve the immune system, antioxidant status and gut health. Further studies are needed to deepen the understanding of the role of dietary supplementation with vitamins in pigs on immune system and gut functionality.

Impact of Long-Term Supplementation with Probiotics on Gut Microbiota and Growth Performance in Post-Weaned Piglets.

This study aimed to investigate effects of long-term probiotic supplementation on gut microbiota and growth performance in health weaned piglets. The non-probiotic group (N-PrB) was fed only a basal diet, while the probiotic group (PrB) was fed a basal diet + probiotic combination (E. faecium 1.6 × 108 CFU/g, B. subtilis 2.0 × 108 CFU/g, S. cerevisiae 3.0 × 108 CFU/g). The probiotics combination was provided to the PrB, mixing with the basal diet in 5 kg/ton. As a result, the PrB exhibited significantly improved weight gain compared to the N-PrB (p = 0.00991). In the gut microbiome analysis, the PrB exhibited a significant increasing tendency of α-diversity compared to those of the N-PrB (p < 0.01). In the bacterial relative abundance changes in bacteria comprising the gut microbiota, Ruminococcaceae (p = 0.00281) and Prevotella (p = 0.00687) tended to significantly increase in the PrB, but decreased in the N-PrB. The Eubaterium coprostanoligenes group exhibited an increasing tendency in both groups, but tended to increase more significantly in the PrB compared to the N-PrB (p = 0.00681). Muribaculaceae tended to significantly increase in the N-PrB, but decreased in the PrB (p = 0.002779). In this study, significant differences on the gut microbiome were found according to the probiotics supplementation in the weaned piglets and these gut microbiome changes appeared to improve the growth performance.

Molecular characterization of Escherichia coli virulence markers in neonatal and postweaning piglets from major pig-producing districts of Uganda.

Piggery production is highly constrained by diseases, with diarrhoea in piglets being a major cause of economic losses to smallholder farmers in Uganda. Enterotoxigenic Escherichia coli (ETEC) is thought to be one of the major etiologies of this diarrhoea. A cross-sectional study was carried out in two high pig-producing districts of Uganda with the aim of determining the significance of piglet diarrhoea and the pathogenic determinants of causative E. coli. A total of 40 households with piglets were visited in each district for a questionnaire survey and faecal sample collection. The questionnaire-based data collected included; demographic data and pig management practices. E. coli were isolated from diarrheic (43) and non-diarrheic (172) piglets and were subjected to antimicrobial susceptibility testing against nine commonly used antimicrobial agents. The E. coli isolates were further screened for the presence of 11 enterotoxin and fimbrial virulence gene markers using multiplex polymerase chain reaction. Data entry, cleaning, verification and descriptive statistics were performed using Microsoft Excel. Statistical analysis to determine any association between the presence of virulence markers and diarrhea in piglets was done using SPSS software (Version 23), with a p value of less than 0.05 taken as a statistically significant association. Escherichia coli were recovered from 81.4% (175/215) of the faecal samples. All the isolates were resistant to erythromycin, and most showed high resistance to tetracycline (71%), ampicillin (49%), and trimethoprim sulfamethoxazole (45%). More than half of the isolates (58.3%) carried at least one of the 11 virulence gene markers tested. EAST1 was the most prevalent virulence marker detected (35.4%), followed by STb (14.8%). Expression of more than one virulence gene marker was observed in 6.2% of the isolates, with the EAST1/STa combination being the most prevalent. Three adhesins; F17 (0.6%), F18 (6.3%) and AIDA-I (0.6%) were detected, with F18 being the most encountered. There was a statistically significant association between the occurrence of piglet diarrhoea and the presence of the AIDA-1 (p value = 0.037) or EAST1 (p value = 0.011) gene marker among the isolates. The level of antimicrobial resistance among E. coli isolates expressing virulence markers were high in the sampled districts. The study established a significant association between presence of EAST1 and AIDA-I virulence markers and piglet diarrhea. Further studies should be carried out to elucidate the main adhesins borne by these organisms in Uganda and the actual role played by EAST1 in the pathogenesis of the infection since most isolates expressed this gene.

Immune response induced by a Streptococcus suis multi-serotype autogenous vaccine used in sows to protect post-weaned piglets

Streptococcus suis is a bacterial pathogen that causes important economic losses to the swine industry worldwide. Since there are no current commercial vaccines, the use of autogenous vaccines applied to gilts/sows to enhance transfer of passive immunity is an attractive alternative to protect weaned piglets. However, there is no universal standardization in the production of autogenous vaccines and the vaccine formulation may be highly different among licenced manufacturing laboratories. In the present study, an autogenous vaccine that included S. suis serotypes 2, 1/2, 5, 7 and 14 was prepared by a licensed laboratory and administrated to gilts using a three-dose program prior to farrowing. The antibody response in gilts as well as the passive transfer of antibodies to piglets was then evaluated. In divergence with previously published data with an autogenous vaccine produced by a different company, the increased response seen in gilts was sufficient to improve maternal antibody transfer to piglets up to 5 weeks of age. However, piglets would still remain susceptible to S. suis disease which often appears during the second part of the nursery period. Vaccination did not affect the shedding of S. suis (as well as that of the specific S. suis serotypes included in the vaccine) by either gilts or piglets. Although all antibiotic treatments were absent during the trial, the clinical protective effect of the vaccination program with the autogenous vaccine could not be evaluated, since limited S. suis cases were present during the trial, confirming the need for a complete evaluation of the clinical protection that must include laboratory confirmation of the aetiological agent involved in the presence of S. suis-associated clinical signs. Further studies to evaluate the usefulness of gilt/sow vaccination with autogenous vaccines to protect nursery piglets should be done.

262 Modulation of vitamin D, calcium and phosphorous metabolism and immune response in pre- and post-weaning piglets under different vitamin D supplementation strategies

Abstract This study evaluated the impact of different vitamin D supplementation strategies to pre- and post-weaning piglets on vitamin D, calcium and phosphorous metabolism and immune status. Sixty piglets were selected at d 2 of age [body weight (BW) = 1.71 ± 0.03 kg] and orally supplemented with saline (CTR) or a solution of 25(OH)D3 at d 2, d 8, and d 21 (0.1, 0.2 and 0.3 mg, respectively) along with UVB exposure every second day from d1 4 up to d 21 (HD). From weaning (d 21) until d 42, CTR animals were supplemented with 2,000 UI of vitamin D3/kg of feed and HD animals were supplemented with 2,000 UI 25(OH)D3/kg. Piglets were sacrificed at d 21, d 28, and d 35 (n = 10/treatment/d) for the collection of blood, jejunum, liver, and kidney samples. Serum 25(OH)D3 concentrations were determined by HPLC and the mRNA expression of genes implicated in vitamin D, calcium and phosphorous metabolism and immune status were assessed by quantitative real-time PCR. Data were analyzed using a 2x3 factorial design. Serum 25(OH)D3 concentrations were 2.8, 3.6, and 2.2-fold greater in HD piglets at d 21, 28, and 35 (P ≤ 0.01), respectively (Table 1). No treatment or treatment x time interaction was detected on the expression of genes related to vitamin D metabolism in the jejunum mucosa and liver (P ≥ 0.19). In kidney, HD piglets had greater expression of CYP27B1 (P = 0.09) and decreased expression of CYP24A1 (P = 0.06). Renal EGR1 expression was greater in HD piglets (P = 0.01). No treatment effect was detected on the expression of genes directly implicated in phosphate or calcium reabsorption (P ≥ 0.16). No treatment or treatment x time interaction was detected on the mRNA expression of selected genes related to immune response in the jejunum mucosa, liver, and kidney (P ≥ 0.14). Independently of vitamin D treatments, time effects were detected for gene expression. The mRNA expression of CYP27B1 increased and that of CYP24A1 decreased from d 28 to 35 (P ≤ 0.04) in kidney. Genes related to calcium (TRPV5) and phosphate (NPT2c) reabsorption in kidney had reduced mRNA expression on d 35 compared with d 21 (P ≤ 0.01). Overall, the mRNA expression of genes related to immune response in all studied tissues was lower at d 35 compared with d 21 (P ≤ 0.08). Bodyweight at slaughter was not affected by treatments at d 21, 28, and 35 (P ≥ 0.29). In conclusion, pre-weaning vitamin D supplementation enhanced vitamin D status at weaning and the use of dietary 25(OH)D3 supplementation was more effective in increasing the vitamin D status post-weaning. The mRNA expression results suggest that greater vitamin D status at weaning and during the first 2 wk post-weaning do not affect calcium and phosphate reabsorption in kidney and the immune defense of pre- and post-weaning piglets.

184 The metabolism of vitamin D is modulated by vitamin C supplementation during porcine reproductive and respiratory syndrome challenge in post-weaning piglets

Abstract This study evaluated the impact of different dietary vitamin D sources combined or not with vitamin C on serum 25(OH)D3 concentrations and the expression of genes related to antimicrobial peptides and to the metabolism of vitamin D, vitamin C, calcium (Ca), and phosphorus (P). From weaning (d 21) until d 68, 27 piglets were fed a post-weaning diet supplemented with: 1,500 IU of vitamin D3 (CTR; n = 9); 200 IU of vitamin D3 + 2,000 IU of 25(OH)D3 (HD; n = 8); or HD + 500 mg/kg of vitamin C (HD+C; n = 10). From d 40 to 68 piglets were exposed to porcine reproductive and respiratory syndrome (PRRS) using a natural disease challenge model. At d 68, after blood collection, all piglets were euthanized for the collection of lung and kidney samples. The concentrations of serum 25(OH)D3 were determined by HPLC and the mRNA expression of genes of interest was assessed by qPCR. Data were analyzed in a one-way analysis of variance with three treatments. At d 40 (after 19 d of supplementation), serum 25(OH)D3 concentrations were greatest for HD+C (22.48 ± 1.25 ng/mL), intermediate for HD (17.43 ± 0.84 ng/mL), and least for CTR (8.54 ± 0.65 ng/mL) treatments (P &amp;lt; 0.01). At d 68 (after 28 d of PRRS challenge) these values were greatest for HD (14.64 ± 2.77 ng/mL), intermediate for CTR (6.22 ± 0.59 ng/mL), and least for HD+C (2.18 ± 0.13 ng/mL; P &amp;lt; 0.01). No treatments effect was detected on pulmonary CYP27B1, RXRα, SLC23A1, RIGI, PR-39, and pBD1. In lungs, VDR expression was least for HD+C (P ≤ 0.06) whereas MDA5 expression was greatest for HD+C (P ≤ 0.07), and SLC23A2 expression was greatest for HD (P ≤ 0.09; Table 1). No treatments effect was detected on expression of renal FGFR1, KL, RXRα, SLC23A1, SLC23A2, and TPRV5. In kidney, CYP27B1 expression was greatest for HD+C groups (P = 0.03) and CYP24A expression was greatest for HD (P = 0.01). Renal EGR1 and NPT2c expressions were greatest for CTR groups and least for HD+C (P = 0.09) whereas WNK4 expression was greatest for HD+C and least for CTR (P = 0.10). Renal VDR expression was greatest for HD groups and least for HD+C (P ≤ 0.05). In conclusion, vitamin C supplementation increased serum 25(OH)D3 concentrations in pre-challenged piglets. These concentrations were reduced by vitamin C supplementation after PRRS challenge, which may be related to a greater synthesis of the active form of vitamin D in the kidney. Little effects were detected on pulmonary antimicrobial peptides, but the gene expression related to renal P reabsorption was influenced by HD+C whereas Ca reabsorption was apparently not impacted by treatments.

259 Effect of very low calcium diet supplemented with microbial phytase in post-weaning piglets

Abstract Young piglets have an immature intestine that provides limited gastric acidity to digest nutrients compared with later stages of growth. Food has the intrinsic capacity to modify gastric acidity, particularly in relation to their concentrations of limestone, the ingredient with the greatest capacity to bind to acid. An experiment was conducted to evaluate the impacts of reducing dietary calcium (Ca) by reducing calcium supplementation immediately after weaning; compared with the recommendations of the NRC (2012), in association with phytase supplementation. The treatments were distributed during 3 phases [Phase 1 (P1, d 0-9), 2 (P2, d 10-16) and 3 (P3, d 17-35)]. Treatments were: 1) a diet low Ca that did not contained limestone during phase 1 (LowCa), P1 to P3 respectively, 0.51-0.60-0.65 % Ca and 0.48-0.43-0.38 % standardized ileal digestible P (STTD P), 2), diet 1 with microbial phytase (LowCa+PhytM); P1 to P3 respectively, 0.51-0.60-0.65 % Ca and 0.48-0.43-0.38% STTD P with 750 FTU phytase, and 3) a diet fulfilling requirement (NormalCa+PhytM) P1 to P3 respectively, 0.85-0.80-0.70 % Ca and 0.48-0.43-0.38 % STTD P with 750 FTU phytase. Piglets (n = 120) were allocated to 6 pens of 5 piglets per treatment in function of initial body weight (BW; 6.12 ± 0.028 kg). On d 0, 15 and 36, dual X-ray (DXA) bone densitometry was used to measure body fat, lean and mineral content (BMC) compositions using 8 piglets per treatment. At the end of phase 1 (d 9) a blood sample was collected. Data were analyzed using the SAS MIXED procedure with Tukey’s test to compare means. No differences were observed in growth performance or DXA measurements during the first phase. On d 9, LowCa piglets showed signs of hypocalcaemia with reduced plasma Ca (P = 0.03), increased plasma P (P = 0.02) and a lower Ca:P ratio in plasma (P = 0.04). From d 9-15, piglets that had received LowCa+PhytM showed greater average daily gain (ADG; P = 0.002) while other criteria did not differ between treatments. On d 15, the body composition evaluated by DXA showed no difference among dietary treatments. During phase 3, final BW and average daily feed intake were not modified by dietary treatments, while average daily gain and feed efficiency were greater in LowCa than in NormalCa+PhytM (+7.3 and 6.7%, respectively), and LowCa+PhytM was intermediate. Body composition on d 35 showed no difference among treatments while a tendency (P = 0.095) for greater BMC deposition (g/d) in LowCa in comparison with NormalCa+PhytM (+1.3 %). The implemented LowCa strategy resulted in momentary hypocalcemia which probably activated homeostatic mechanisms allowing piglets to be more efficient in using minerals and possibly other nutrients leading to better growth performance, without impact on bone mineralization.

Enhancing Weaned Piglet Health and Performance: The Role of Autolyzed Yeast (Saccharomyces cerevisiae) and β-Glucans as a Blood Plasma Alternative in Diets.

The objective of this study was to evaluate the inclusion of the autolyzed yeast (AY) Saccharomyces cerevisiae with or without an immunomodulator (1,3/1,6 β-glucans) as a total/partial substitute for blood plasma (BP) in the diet of post-weaning piglets; zootechnical performance, intestinal health and microbiota, immune responses and energy metabolism were assessed. A total of 240 castrated male and female piglets, with a mean age of 22 days and mean initial weight of 5.24 ± 0.82 kg, were randomly divided into blocks of four treatments with 12 replicates. The dietary inclusions were blood plasma (BP), autolyzed yeast (AY), autolyzed yeast + immunomodulator (AYI) and 50% BP and 50% AY (BPAY). In pre-initial phase II (29-35 days), piglets fed AY showed better feed conversion (FCR = 1.358) than the piglets in the BP (1.484), AYI (1.379) and BPAY (1.442) groups, i.e., 8.49% (0.126), 1.52% (0.021) and 4.50% (0.084), respectively (p = 0.0293). In the total period (21-42 days), better FCR was observed in the AYI (1.458) group, i.e., 4.64% (0.071), 1.15% (0.017) and 4.58% (0.070), than in the BP (1.529), AY (1.475) and BPAY (1.528) groups, respectively (p = 0.0150). In piglets fed AY (n = 3) and BPAY (n = 2), there was a reduction in the number of medications, i.e., 82.35% (-14n) and 88.23% (-15n), respectively (p = 0.0001), compared with that in the BP group (n = 17). In the AY group (73.83 mg/dL), AYI group (69.92 mg/dL), and BPAY group (69.58 mg/dL), piglets exhibited increases in triglyceride levels of 79.32%, 69.83%, and 69.00%, respectively, in comparison to those in the BP group, which had triglyceride levels of 41.17 mg/dL (p = 0.0400). The beta-hydroxybutyrate concentration in the AY group (79.96 ng/μL) was lower by 31.95%, 22.64%, and 5.89% compared to the BP group (117.50 ng/μL), AYI group (103.36 ng/μL), and BPAY group (84.67 ng/μL), respectively (p = 0.0072). In the AYI group, there was modulation of the microbiota, with an increase in the relative abundance of bacteria of the genera Lactobacillus, Collinsella and Bulleidia. AY, associated or not associated with an immunomodulator, is a potential substitute for BP in diets for piglets in the nursery phase, with positive effects on immune, metabolic, and intestinal microbial performance.

Blend of organic acids improves gut morphology and affects inflammation response in piglets after weaning

Weaning is a stressful period in a piglet’s life, when many morphological and functional changes occur in the gastrointestinal tract. Examples are an alteration of the barrier function and an increase in production of cytokines, suggesting the immune system of the GIT is activated after weaning. The goal of this study was to evaluate the effect of a commercially available feed additive based on short and medium chain fatty acids on supporting intestinal health and reduce inflammation in the intestine of post-weaning piglets. Seventy piglets were divided over 2 treatments, a control diet and a blend of short and medium chain fatty acids, including butyrate. On day 0, 15, 30 and 45 after weaning blood samples and intestinal tissue samples were collected from sacrificed piglets. Blood and tissue samples were analysed for cytokine gene expression, and tissue samples from jejunum and ileum were analysed on morphology and gene expression of tight junctions. Results show that the use of a blend of short and medium chain fatty acids, including butyrates, improved intestinal morphology, measured by villous length and v/c ratio, reduced expression of tight junction proteins and influenced cytokine production in the intestine, implicating that the use of organic acids as feed additives potentially can reduce damage caused by weaning to the intestinal barrier and due to the higher absorption capacity of the villi potentially improve nutrient absorption.