Efficacy of Feed Additive Containing Bentonite and Enzymatically Hydrolyzed Yeast on Intestinal Health and Growth of Newly Weaned Pigs under Chronic Dietary Challenges of Fumonisin and Aflatoxin

This study aimed to investigate the efficacy of a feed additive containing bentonite and enzymatically hydrolyzed yeast on the intestinal health and growth of newly weaned pigs under chronic dietary exposure to fumonisin and aflatoxin. Newly weaned pigs were randomly allotted to one of four possible treatments: a control diet of conventional corn; a diet of corn contaminated with fumonisin and aflatoxin; a diet of mycotoxin-contaminated corn with 0.2% of feed additive; and a diet of mycotoxin contaminated corn with 0.4% of feed additive. We observed lower average weight gain and average daily feed intake in pigs that were fed only mycotoxin-contaminated corn compared to the control group. Feed additive supplementation linearly increased both average weight gain and feed intake, as well as tumor necrosis factor-alpha. In the jejunum, there was an observed decrease in immunoglobulin A and an increase in claudin-1. Additionally, feed additive supplementation increased the villus height to crypt depth ratio compared to the control. In conclusion, feed additives containing bentonite and enzymatically hydrolyzed yeast could mitigate the detrimental effects of mycotoxins on the growth performance of newly weaned pigs by improving intestinal integrity and positively modulating immune response.

Effects of Equol Supplementation on Growth Performance, Redox Status, Intestinal Health and Skeletal Muscle Development of Weanling Piglets with Intrauterine Growth Retardation

Animals with intrauterine growth retardation (IUGR) usually undergo injured postnatal growth and development during the early period after birth. Equol (Eq), an isoflavan produced by gut bacteria in response to daidzein intake, has various health benefits. Therefore, the objective of this study was to evaluate whether Eq supplementation can influence the growth performance, redox status, intestinal health and skeletal muscle development of weanling piglets with IUGR. A total of 10 normal-birth-weight (NBW) newborn female piglets and 20 newborn female piglets with IUGR were selected. After weaning at the age of 21 d, 10 NBW piglets and 10 IUGR piglets were allocated to the NBW group and IUGR group, respectively, and offered a basal diet. The other 10 IUGR piglets were allocated to the IUGR + Eq group and offered a basal diet with 50 mg of Eq per kg of diet. The whole trial lasted for 21 d. At the end of the feeding trial, all piglets were sacrificed for the collection of serum, intestinal tissues and skeletal muscles. Supplementation with Eq increased the average daily gain (ADG), average daily feed intake (ADFI), duodenal villus height to crypt depth ratio (V/C), jejunal villus height and V/C, but reduced the duodenal crypt depth in neonatal piglets with IUGR. Meanwhile, Eq supplementation elevated the activities of superoxide dismutase (SOD) and catalase (CAT) in the serum and duodenum and the activity of SOD in the jejunum, but lowered malondialdehyde (MDA) content in the serum, jejunum and ileum of piglets with IUGR. In addition, supplementation with Eq reduced diamine oxidase (DAO) activity and the levels of D-lactate and endotoxin in serum, and the tumor necrosis factor-α (TNF-α) level in jejunum and ileum, whereas the concentration of serum immunoglobulin G (IgG) and the mRNA levels of intestinal barrier-related markers in jejunum and ileum of IUGR piglets were increased. Furthermore, supplementation with Eq elevated the percentage of fast-fibers and was accompanied with higher mRNA expression of myosin heavy chain IIb (MyHC IIb) and lower mRNA levels in MyHC I in the longissimus thoracis (LT) muscle of IUGR piglets. In summary, Eq supplementation can promote antioxidant capacity, maintain intestinal health and facilitate skeletal muscle development, thus resulting in the higher growth performance of IUGR piglets.

Quantification of secretory IgA and mucin excretion and their contributions to total endogenous amino acid losses in roosters that were fasted or precision-fed a nitrogen-free diet or various highly digestible protein sources

The objective of this study was to quantify total secretory IgA (sIgA) and mucin excretion via excreta in roosters fed diets containing highly digestible protein sources and to determine their proportional contributions to total endogenous amino acid (AA) losses. Precision-fed rooster assays with 24 h excreta collections were conducted using conventional White Leghorn roosters (4-8 roosters per treatment). In Experiment 1, roosters were fasted or precision-fed 30 g (crop intubation) of a nitrogen-free (NF) or semi-purified diet containing 10% casein. Roosters in Experiment 2 received a NF or semi-purified diet containing either 10% casein, 17% whole egg, 10% egg white, 9.8% soy protein isolate, 10.2% chicken breast meat, 11.2% spray-dried animal plasma (SDAP), or an AA mixture containing the same AA as casein. A Latin square design was used in Experiment 3, where roosters received NF or semi-purified diets containing either 10% casein, 17% whole egg, or 9.6% of a crystalline AA mixture to evaluate both diet and individual bird effects. In Experiment 1, mucin excretion did not differ (P > 0.05) among treatments; however, total sIgA excretion was lower for fasted birds, intermediate for the NF diet, and highest for casein (P < 0.05). Total endogenous AA losses (proportion of the total) from sIgA were higher for roosters fed casein, whereas mucin contributions were higher for fasted roosters (P < 0.05). In Experiment 2, sIgA excretion did not differ (P > 0.05) among treatments; however, mucin excretion was reduced for NF, whole egg, egg white, and chicken breast compared with casein and SDAP. In Experiment 3, sIgA and mucin excretion did not differ (P > 0.05) among treatments; however, sIgA excretion differed among individual roosters (7-27 mg/24 h; P < 0.05). Overall, fasting reduced sIgA excretion and sIgA and mucin excretion were affected by dietary protein source. Further, roosters excreted a substantial amount of sIgA, and sIgA and mucin were considerable contributors to total endogenous AA losses.

Lycopene Affects Intestinal Barrier Function and the Gut Microbiota in Weaned Piglets via Antioxidant Signaling Regulation

BACKGROUND

In pig production, early and abrupt weaning frequently causes weaning stress, which manifests as oxidative damage, barrier disruption, and digestion and absorption capacity declines. Lycopene exhibits beneficial antioxidant capacity in both humans and other animal models.

OBJECTIVES

The present study aimed to investigate the effects of lycopene supplementation on early weaning stress in piglets and the underlying mechanisms by examining the oxidative stress state, gut intestinal barrier function, and the gut microbiota.

METHODS

Twenty-four 21-day-old weaned piglets [Duroc × (Landrace × Yorkshire); castrated males; 5.48 ± 0.10 kg initial body weight] were randomly assigned to 2 treatments. The piglets were fed a basal diet (control treatment) or a basal diet supplemented with 50 mg/kg lycopene (lycopene treatment) for 28 days. The serum lipid levels, serum and jejunum enzyme activities, jejunum morphology, mRNA and protein expression, and gut microbiota were determined.

RESULTS

Compared with the control treatment, lycopene supplementation increased the serum catalase activity (P = 0.042; 62.0%); serum total cholesterol concentration (P = 0.020; 14.1%); and jejunum superoxide dismutase activity (P = 0.032; 21.4%), whereas it decreased serum (P = 0.039, 23.0%) and jejunum (P = 0.047; 20.9%) hydrogen peroxide concentrations. Additionally, lycopene increased the mRNA and protein expression of NFE2-like bZIP transcription factor 2 (214.0% and 102.4%, respectively) and CD36 (100.8% and 145.2%, respectively) in the jejunum, whereas it decreased the mRNA and protein expression of Kelch-like ECH-associated protein 1 (55.6% and 39.8%, respectively ). Lycopene also improved jejunal morphology, increasing the villus height (P = 0.018; 27.5%) and villus:crypt ratio (P < 0.001; 57.9%). Furthermore, it increased the abundances of potentially beneficial bacterial groups, including Phascolarctobacterium and Parasutterella, and decreased those of potentially pathogenic bacterial groups, including Treponema_2 and Prevotellaceae_unclassified.

CONCLUSIONS

Lycopene supplementation strengthens the intestinal barrier function and improves the gut microbiota in weaned piglets by regulating intestinal antioxidant signaling.

Extruded Enzyme-Added Corn Improves the Growth Performance, Intestinal Function, and Microbiome of Weaning Piglets

The objective of this study was to evaluate the effects of extruded corn with added amylase under different moisture conditions on the growth performance, intestinal function, and microbiome of weaning piglets. Fourty-eight 24-day-old weaning piglets (Duroc × Landrace × Yorkshire, weaned at 22 ± 1 d) with an initial body weight of 6.76 ± 0.15 kg were randomly assigned to one of four dietary treatments with six replicates per treatment and two pigs per replicate: (1) NL (adding 7.5% water before corn extrusion, negative treatment with low moisture); (2) NH (adding 15.0% water before corn extrusion, negative treatment with high moisture); (3) PL (adding 7.5% water and 4 kg/t α-amylase before corn extrusion, positive treatment with low moisture); and (4) PH (adding 15% water and 4 kg/t α-amylase before corn extrusion, positive treatment with high moisture). Results showed that amylase supplementation (4 vs. 0 kg/t) increased the contents of small molecular oligosaccharides of extruded corn (p < 0.05). Amylase supplementation significantly improved the average daily feed intake, apparent total tract digestibility (ATTD) of dry matter, crude protein, gross energy, crude fat, ash, phosphorus, and calcium, and also increased the activities of jejunal trypsin, α-amylase, lipase, sucrase, maltase, γ-glutamyl transferase and alkaline phosphatase activities, improved the duodenal, jejunal and ileal morphology, and increased the relative mRNA expressions of the ZO-1, OCLN, SGLT1, and GLUT2 genes in the jejunum (p < 0.05), whereas it decreased the contents of isobutyric acid in cecal digesta, as well as acetic acid and isobutyric acid in colonic digesta (p < 0.05). Moreover, the linear discriminant analysis effect size (LEfSe) showed that piglets fed extruded corn with added enzymes contained less intestinal pathogenic bacteria, such as Holdemanella and Desulfovibrio, compared with piglets fed just extruded corn. In summary, the results of the present study indicated that the supplementation of α-amylase during the conditioning and extruding process of corn increased the small molecular oligosaccharide content of corn starch. Moreover, piglets receiving extruded enzyme-added corn had better growth performance, which was associated with the improved intestinal digestive and absorptive function, as well as the intestinal microbiome.

Effects of fermented wheat bran and yeast culture on growth performance, immunity, and intestinal microflora in growing-finishing pigs

This study was conducted to evaluate the effects of feeding fermented wheat bran (FWB) and yeast culture (YC) on growth performance, immune levels, and intestinal microflora in growing-finishing pigs. In total, 96 crossbred pigs were randomly distributed into four treatments with four replicates pens and six pigs per pen. This study was performed using a 2 × 2 factor design: 1) CON (basal diet), 2) FWB (basal diet + 5% FWB), 3) YC (basal diet + 2% YC), and 4) FWB + YC (basal diet + 5% FWB + 2% YC). Dietary FWB supplementation significantly increased the average daily gain and significantly decreased the feed gain ratio of growing-finishing pigs (P < 0.05). Supplementation of FWB and YC improved the immune capacity and reduced the inflammation level of growing-finishing pigs (P < 0.05). In addition, pigs fed FWB, YC, and FWB + YC diets showed better intestinal development and morphology compared with those CON pigs. The relative abundance of Streptococcus in the FWB group was significantly lower than that in the CON group (P < 0.05), and the relative abundance of probiotics (unclassified_f_Lachnospiraceae, Turicibacter) increased significantly (P < 0.05). Furthermore, the relative abundance of probiotics (Lactobacillus, norank_f_Muribaculaceae) in the YC group was significantly increased compared with the CON group (P < 0.05). The results of this study observed positive effects of FWB and YC on growing-finishing pigs, which provides insights into the application of biological feed in swine industry.

Effects of spray-dried animal plasma on growth performance, survival, feed utilization, immune responses, and resistance to Vibrio parahaemolyticus infection of Pacific white shrimp (Litopenaeus vannamei)

Spray-dried animal plasma (SDP) in feed for several animal species provides health benefits, but research about use of SDP in shrimp feed is very limited. The objectives of the present study were to investigate the effects of dietary SDP on growth performance, feed utilization, immune responses, and prevention of Vibrio parahaemolyticus infection in Pacific white shrimp (Litopenaeus vannamei). In Experiment 1, the post-larvae were divided into five groups (four tank/group and 80 shrimp/tank) and fed four times daily diets with porcine SDP at 0, 1.5, 3, 4.5, and 6% of the diet for 45 days. In Experiment 2, the surviving shrimp from Experiment 1 were redistributed into six groups: four SDP groups as in Experiment 1 plus the positive and negative controls (four tank/group and 30 shrimp/tank). They were then challenged with V. parahaemolyticus by immersion at 10⁵ colony-forming units (CFU)/mL and were fed with the same diets for another 4 days. In Experiment 1, shrimp fed 4.5% or 6% SDP diets had significantly higher body weight, survival rate, and improved feed conversion ratio. The immune parameters (total hemocyte count and phagocytic, phenoloxidase, and superoxide dismutase activities) of the shrimp fed 3–6% SDP diets also showed significant enhancement compared to the control. In Experiment 2, the survival rates of the 3–6% SDP groups were significantly higher than the positive control at day 4 after the immersion challenge. Likewise, the histopathological study revealed milder signs of bacterial infection in the hepatopancreas of the 3–6% SDP groups compared to the challenged positive control and 1.5% SDP groups. In conclusion, shrimp fed diets with SDP, especially at 4.5–6% of the diet, showed significant improvement in overall health conditions and better resistance to V. parahaemolyticus infection.

Innovative high digestibility protein feed materials reducing environmental impact through improved nitrogen-use efficiency in sustainable agriculture

Sustainable development in agriculture brings both environmental and economic benefits. Contemporary agriculture is also about increasing nutrient use efficiency, especially nitrogen, as the critical nutrient causing the most significant environmental pressure. This creates the need to produce highly digestible protein feed with high bioavailability, reducing losses of biogenic elements to feces. In this review, the latest trends and the potential for their implementation in sustainable agriculture have been compared, as well as the need to reduce the negative environmental impact of agriculture has been demonstrated. Applying local protein sources to feed animals reduces greenhouse gas emissions associated with transportation. The production of highly digestible fodder leads to a reduction in environmental pollution caused by excessive nitrogen outflows. Another approach indecreasing ammonia emissions from livestock farming is feed protein reduction and amino acid supplementation. All of the aforementioned approaches may result in beneficial long-term changes, contributing to environmental safety, animal welfare and human health.

Spray-Dried Plasma Improves Body Weight, Intestinal Barrier Function, and Tibia Strength during Experimental Constant Heat Stress Conditions

Simple Summary

Broilers are especially heat sensitive because of the absence of sweat glands and their elevated metabolism. Under commercial conditions, extremely high temperatures (heat stress) reduce their performance. This research aimed to assess spray-dried feeding plasma (SDP) during constant heat stress (HS) on the performance, intestinal permeability, and bone strength in broilers. Chickens fed with a diet supplemented with SDP increased both their body weight and body weight gain compared to the HS control group. At the end of the study (d 42 of age), chickens fed with SDP significantly alleviated the increased gut leakage induced by HS and showed a significant increase in tibia strength compared with control HS chickens. The results in the present study suggest SDP mends gut integrity, hence reducing chronic systemic inflammation.

Abstract

The aim of this study was to see how spray-dried plasma (SDP) supplementation affected broiler chicken performance, intestinal permeability, and bone strength during persistent heat stress. One-day-old chicks (n = 480) were randomly assigned into twelve environmental corrals; four thermoneutral (TN-negative control, maintained at 24 °C from d 21–42); four heat stress (HS, exposed to 35 °C from d 21–42); and four heat stress treated with 2% SDP in the feed until d 28 followed by 1% SDP until d 42 (HS-SDP). The performance and serum levels of fluorescein isothiocyanate-dextran (FITC-d) were evaluated at d 21, 28, 35, and 42. The tibias strength was evaluated on d 21 and 42. The increment in chicken temperature (p < 0.05) was observed two h following the increase in environmental temperature in both HS groups and was associated with decreased performance parameters compared with the TN group. At d 42 of age, the chickens exposed to HS had an impaired gut permeability and decreased tibia strength compared to the TN group (p < 0.05). However, partially feeding SDP mitigated these adverse effects significantly. These findings imply that using SDP strategically during stressful times, such as prolonged heat stress, may help mitigate its negative consequences.

The impact of porcine spray-dried plasma protein and dried egg protein harvested from hyper-immunized hens, provided in the presence or absence of subtherapeutic levels of antibiotics in the feed, on growth and indicators of intestinal function and physiology of nursery pigs

The objective of this experiment was to compare the effects of spray-dried plasma protein (SDPP) and dried egg protein (DEP), without (AB-) or with (AB+) in-feed antibiotics, on growth performance and markers of intestinal health in nursery pigs raised in commercial conditions. This 42-d experiment utilized 1,230 pigs (4.93 ± 0.04 kg body weight; approximately 15-18 d of age). Pigs were randomly assigned to one of six dietary treatments that were arranged as a 2 × 3 factorial of in-feed antibiotics (AB- vs. AB+) and a specialty protein additive (none [CON], porcine SDPP, or DEP). Diets were fed in four phases with phases 3 and 4 as a common diet across all treatments. Specialty protein additives were fed in phases 1 (0-13 d; 3% SDPP, and 0.20% DEP) and 2 (13-26 d; 2% SDPP, and 0.10% DEP). Antibiotics were fed in phases 1-3 (662 mg chlortetracycline [CTC]/kg, 28 mg carbadox/kg, and 441 mg CTC/kg, respectively). Ileal tissue and blood samples were collected from 48 pigs (8 per treatment) on d 20. Data were analyzed using PROC MIXED of SAS (9.4) with pen as the experimental unit; protein additives, antibiotics, and their interaction were fixed effects and block was a random effect. The pigs experienced naturally occurring health challenges in weeks 2 and 4. In the AB- diets, SDPP and DEP increased average daily gain (ADG; P = 0.036) and average daily feed intake (ADFI; P = 0.040) compared to CON; in the AB+ diets, neither SDPP nor DEP increased ADG or ADFI compared to CON but SDPP did increase these parameters over DEP. The SDPP and DEP diets decreased the number of individual medical treatments compared to CON (P = 0.001). The AB+ increased ileal mucosal interleukin (IL)-1 receptor antagonist (P = 0.017). Feeding DEP reduced the concentration of mucosal IL-1β compared to CON, but not SDPP (P = 0.022). There was a trend for SDPP and DEP to increase villus height:crypt depth compared to CON (P = 0.066). Neither antibiotics or protein additive affected serum malondialdehyde concentration or ileal mRNA abundance of claudin-3 or 4, occludin, or zonula occludens-1 (P > 0.10). In conclusion, SDPP and DEP improved growth performance of weaned pigs in the absence of antibiotics but neither improved growth compared to CON when feeding standard antibiotic levels. The specialty proteins had a positive effect on health; specialty proteins and antibiotics were able to modulate some markers of intestinal inflammation and morphology.

Defatted Rice Bran Supplementation in Diets of Finishing Pigs: Effects on Physiological, Intestinal Barrier, and Oxidative Stress Parameters

Simple Summary

Most studies on dietary fiber mainly focus on the digestibility of feed nutrients and microbial flora, etc. However, insufficient attention has been paid to the regulation of immune and oxidative stress of the intestinal tract by dietary fiber. This study investigated the effects of varying levels of defatted rice bran replacing corn on physiological, intestinal barrier, and oxidative stress parameters in finishing pigs. Based on the current findings, a high diet of rice bran will not only reduce the level of inflammatory factors in the peripheral blood of finishing pigs, but also enhance the healthy level of the colon through mucin2 and keap1-Nrf2 pathways. Our results can be used as reference for dietary rice bran to improve intestinal health in finishing pigs.

Abstract

Rice bran is a waste product with low cost and high fiber content, giving it an added advantage over corn and soybean meal, which have to be purchased and always at a relatively higher cost. Under the background of increased attention to sustainable agriculture, it is significant to find alternative uses for this byproduct. A total of 35 finishing pigs were allotted to five dietary treatments: a control group with basal diet and four experimental diets where corn was equivalently substituted by 7%, 14%, 21%, and 28% defatted rice bran (DFRB), respectively. With increasing levels of DFRB, the neutrophil to lymphocyte ratio (NLR) linearly decreased (p < 0.05). In the jejunum, the mRNA level of nuclear factor erythroid-2 related factor-2 (Nrf2) exhibited a quadratic response (p < 0.01) with incremental levels of DFRB. In the colon, the mRNA levels of mucin 2 (MUC2), Nrf2, and NAD(P)H: quinone oxidoreductase 1 (NQO1) were upregulated (linear, p < 0.05) and heme oxygenase-1 (HO-1) was upregulated (linear, p < 0.01). Overall, using DFRB to replace corn decreased the inflammatory biomarkers of serum and showed potential function in modulating the intestinal barrier by upregulating the mRNA expression levels of MUC2 and downregulating that of Nrf2, NQO1, and HO-1 in the colon.

Responses of intestinal morphology and function in offspring to heat stress in primiparous sows during late gestation

Late gestation is a key period for intestinal development. Maternal heat exposure may induce intestinal dysfunction of offspring. To investigate the responses of intestinal morphology and function of offspring to the maternal heat stress (HS), twelve first-parity Landrace × Large White sows were assigned to thermoneutral (TN) (18-22 °C; n = 6) or HS (28-32 °C; n = 6) treatment groups at 85 d of gestation until natural farrowing. Twenty-four newborn piglets (two piglets at medium body weight from each litter) were randomly selected and divided into in utero thermoneutral (IUTN, n = 12) and heat-stressed (IUHS, n = 12) groups according to the sow's treatment. Blood and intestinal samples were harvested to evaluate stress hormone levels, intestinal morphology, integrity and barrier function in the newborn piglets. Our results showed that maternal HS piglets exhibited increased serum adrenocorticotropic hormone (ACTH) concentration compared with that observed in the IUTN group. IUHS piglets showed lower lactase activities in the jejunum and ileum, whereas no significant differences were found between the two groups in the length of intestine, villus length or crypt depth. Serum diamine oxidase (DAO) activity was increased in IUHS piglets. IUHS piglets also exhibited decreased ZO-1, ZO-2 and MUC2 mRNA expression in the jejunum, while the protein levels were not affected. Additionally, IUHS piglets had a lower apoptotic percentage and FAS mRNA expression in the jejunum than those in the IUTN group. Taken together, these results demonstrate that high ambient temperature during late gestation of primiparous sows causes stress response in neonatal piglets, compromising intestinal permeability and mucosal barrier function, which may be partly mediated by inducing intestinal apoptosis.

Improvement of growth performance and parameters of intestinal function in liquid fed early weanling pigs1

Liquid feeding, a widely used technique, has been applied as a feeding technique commonly in global swine production. The objective of this study was to evaluate the effects of liquid feeding on growth performance, nutrient digestibility, and intestinal barrier functions during the early weaning period in pigs. Three hundred and sixty 24-d-old weanling pigs (Duroc × Landrace × Yorkshire) with BW of 6.98 ± 0.15 kg were randomly assigned to a control diet (dry fed basal diet, CON) or as meal mixed with water in the ratio 1:4 (liquid fed basal diet, LF) with 6 replicates per treatment and 30 weanling pigs per replicate. The study lasted 7 d. On days 4 to 7, fresh fecal samples were collected to evaluate apparent total tract digestibility (ATTD) of nutrients. After 7 d, 2 weanling pigs per pen were euthanized and physiological samples were obtained. Results showed that LF increased (P < 0.05) ADG (281 g vs. 183 g), ADFI (374 g vs. 245 g), and final BW (8.95 kg vs. 8.26 kg) compared with CON. Compared with CON, LF significantly decreased (P < 0.05) serum cortisol and d-lactate concentrations as well as the activity of diamine oxidase, enhanced (P < 0.05) the ATTD of ether extract and ash, increased (P < 0.05) the activities of amylase, lipase, and lactase in the jejunal mucosa. Furthermore, LF had higher (P < 0.05) villus height and villi height:crypt depth and increased (P < 0.05) mRNA expressions of insulin-like growth factors-1 receptor (IGF-1R), claudin-2 (CLDN-2), zonula occludens-1 (ZO-1), and zonula occludens-2 (ZO-2) in the jejunum. Moreover, LF had lower (P < 0.05) abundances of total bacteria and Escherichia coli and higher (P < 0.05) concentrations of acetic acid and butyric acid in cecal digesta. Altogether, the results indicated that liquid feeding not only promoted growth performance but also improved intestinal health by enhancing gut barrier functions in weanling pigs.

Resveratrol improves intestinal barrier function, alleviates mitochondrial dysfunction and induces mitophagy in diquat challenged piglets1

This study evaluated whether resveratrol can alleviate intestinal injury and enhance the mitochondrial function and the mitophagy level in diquat induced oxidative stress of piglets.

Diquat-induced oxidative stress increases intestinal permeability, impairs mitochondrial function, and triggers mitophagy in piglets

In the present study, we investigated the influence of diquat-induced oxidative stress on intestinal barrier, mitochondrial function, and the level of mitophagy in piglets. Twelve male Duroc × Landrace × Yorkshire 35-d-old pigs (weaned at 21 d of age), with an average body of 9.6 kg, were allotted to two treatments of six piglets each including the challenged group and the control group. The challenged pigs were injected with 100 mg/kg bodyweight diquat and control pigs injected with 0.9% (w/v) NaCl solution. The results showed that diquat injection decreased ADFI and ADG. Diquat decreased (P < 0.05) the activities of superoxide dismutase and glutathione peroxidase and increased (P < 0.05) the malondialdehyde concentrations. The lower (P < 0.05) transepithelial electrical resistance and higher (P < 0.05) paracellular permeability of fluorescein isothiocyanatedextran 4 kDa were found in diquat challenged piglets. Meanwhile, diquat decreased (P < 0.05) the protein abundance of claudin-1, occluding, and zonula occludens-1 in jejunum compared with the control group. Diquat-induced mitochondrial dysfunction, as demonstrated by increased (P < 0.05) reactive oxygen species production and decreased (P < 0.05) membrane potential of intestinal mitochondria. Diquat-injected pigs revealed a decrease (P < 0.05) of mRNA abundance of genes related to mitochondrial biogenesis and functions, PPARg coactivator-1α, mammalian-silencing information regulator-1, nuclear respiratory factor-1, mt transcription factor A, mt single-strand DNA-binding protein, mt polymerase r, glucokinase, citrate synthase, ATP synthase, and cytochrome coxidase subunit I and V in the jejunum. Diquat induced an increase (P < 0.05) in expression of mitophagy-related proteins, phosphatase and tensin homologue deleted on chromosome 10-induced putative kinase, and Parkin in the intestinal mitochondria, as well as an enhancement of the ratio of light chain 3-II (LC3-II) to LC3-I content in the jejunal mucosa. These results suggest that oxidative stress disrupted the intestinal barrier, caused mitochondrial dysfunction, and triggered mitophagy.

Weaning disrupts intestinal antioxidant status, impairs intestinal barrier and mitochondrial function, and triggers mitophagy in piglets

In the present study, we investigated the influence of weaning on antioxidant status, intestinal integrity, mitochondrial function, and the mitophagy level in piglets (weaned at 21 d) during the 1 wk after weaning. The redox status was measured by antioxidant enzymes activities, related genes expression, and malondialdehyde (MDA) content in jejunum. The intestinal barrier function was assessed by the Ussing chamber and expression of tight junction proteins in the jejunum. The function of intestine mitochondria was measured by mitochondrial DNA (mtDNA) content and activities of mitochondria oxidative phosphorylation complexes. The levels of light chain 3-1 (LC3-I), light chain 3-II (LC3-II), PTEN-induced putative kinase 1 (PINK1), and Parkin were determined to investigate whether mitophagy is involved in the weaning process. The results showed that, as compared with the preweaning phase (d 0), weaning suppressed (P < 0.05) the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) on d 3 and d 7 postweaning, decreased (P < 0.05) the expression of copper and zinc superoxide dismutase (Cu/Zn-SOD), manganese-containing superoxide dismutase (Mn-SOD) on d 3 postweaning, declined (P < 0.05) the level of glutathione peroxidase 1 (GPX-1) and glutathione peroxidase 4 (GPX-4) on d 3 and d 7 postweaning, and increased (P < 0.05) MDA content in jejunum on d 3 and d 7 postweaning. The jejunal transepithelial electrical resistance and levels of occludin, claudin-1, and zonula occludens-1 on d 3 and d 7 postweaning were reduced (P < 0.05), and paracellular flux of fluorescein isothiocyanatedextran (4 kDa) on d 3 and d 7 postweaning was increased (P < 0.05). Weaning induced mitochondrial dysfunction, as demonstrated by decreased (P < 0.05) content of mtDNA on d 3 and d 7 postweaning and declined (P < 0.05) activities of mitochondria complexes (I, II, III, IV) in jejunum on d 1, d 3, and d 7 postweaning. Weaning led to an increased (P < 0.05) expression level of mitophagy-related proteins, PINK1 and Parkin, in the intestinal mitochondria, as well as an enhancement (P < 0.05) of the ratio of LC3-II to LC3-I content in the jejunal mucosa on d 1, d 3, and d 7 postweaning. These results suggest that weaning disrupted intestinal oxidative balance, and this imbalance may impair intestinal barrier and mitochondrial function and trigger mitophagy in piglets.

Chlorogenic Acid Improves Intestinal Development via Suppressing Mucosa Inflammation and Cell Apoptosis in Weaned Pigs

Chlorogenic acid (CGA) is a naturally occurring polyphenol in the human diet and plants, exhibiting antioxidant and anti-inflammatory activities. This study was conducted to investigate the effects of CGA on intestinal development and health in weaned pigs. Twenty-four weaned pigs were randomly assigned to two treatments and fed with a basal diet or a basal diet supplemented with 1000 mg/kg CGA. After a 14 d trial, samples were collected. Compared with the control group, CGA supplementation decreased the serum tumor necrosis factor-α, interleukin-6, and interleukin-1βIL-6 concentrations and elevated the serum immunoglobulin G and jejunal secretory immunoglobulin A concentrations. Meanwhile, jejunal villus height, duodenal and jejunal villus width, and jejunal and ileal villus height/crypt depth were increased by CGA. CGA not only decreased the number of duodenal and jejunal cells in the G0G1 phase but also increased the number of jejunal and ileal cells in the S phase. The percentages of late and total apoptotic cells in jejunum and the ratio of B-cell lymphoma-2-assiciated X protein to B-cell lymphoma-2 (Bcl-2) in duodenum and jejunum were also decreased by CGA supplementation. Finally, CGA upregulated the expression level of Bcl-2 in duodenum and jejunum, whereas it downregulated the expression levels of caspase-3 in duodenum and jejunum, caspase-9 in jejunum, as well as Fas in jejunum and ileum. This study suggested that the beneficial effects of CGA on intestinal development and health are partially due to improvement in immune defense and suppression in excessive apoptosis of intestinal epithelial cells in weaned pigs.

Post weaning diarrhea in pigs: risk factors and non-colistin-based control strategies

Post-weaning diarrhea (PWD) is one of the most serious threats for the swine industry worldwide. It is commonly associated with the proliferation of enterotoxigenic Escherichia coli in the pig intestine. Colistin, a cationic antibiotic, is widely used in swine for the oral treatment of intestinal infections caused by E. coli, and particularly of PWD. However, despite the effectiveness of this antibiotic in the treatment of PWD, several studies have reported high rates of colistin resistant E. coli in swine. Furthermore, this antibiotic is considered of very high importance in humans, being used for the treatment of infections due to multidrug-resistant (MDR) Gram-negative bacteria (GNB). Moreover, the recent discovery of the mcr-1 gene encoding for colistin resistance in Enterobacteriaceae on a conjugative stable plasmid has raised great concern about the possible loss of colistin effectiveness for the treatment of MDR-GNB in humans. Consequently, it has been proposed that the use of colistin in animal production should be considered as a last resort treatment only. Thus, to overcome the economic losses, which would result from the restriction of use of colistin, especially for prophylactic purposes in PWD control, we believe that an understanding of the factors contributing to the development of this disease and the putting in place of practical alternative strategies for the control of PWD in swine is crucial. Such alternatives should improve animal gut health and reduce economic losses in pigs without promoting bacterial resistance. The present review begins with an overview of risk factors of PWD and an update of colistin use in PWD control worldwide in terms of quantities and microbiological outcomes. Subsequently, alternative strategies to the use of colistin for the control of this disease are described and discussed. Finally, a practical approach for the control of PWD in its various phases is proposed.

ZO-2, a tight junction protein involved in gene expression, proliferation, apoptosis, and cell size regulation

ZO-2 is a peripheral tight junction protein that belongs to the membrane-associated guanylate kinase protein family. Here, we explain the modular and supramodular organization of ZO-2 that allows it to interact with a wide variety of molecules, including cell-cell adhesion proteins, cytoskeletal components, and nuclear factors. We also describe how ZO proteins evolved through metazoan evolution and analyze the intracellular traffic of ZO-2, as well as the roles played by ZO-2 at the plasma membrane and nucleus that translate into the regulation of proliferation, cell size, and apoptosis. In addition, we focus on the impact of ZO-2 expression on male fertility and on maladies like cancer, cholestasis, and hearing loss.

Dietary Tryptophan Enhanced the Expression of Tight Junction Protein ZO-1 in Intestine

Dietary amino acids provide various beneficial effects for our health. The aim of the present study was to assess the effects of tryptophan (Trp) supplementation on barrier function. Ninety-six healthy finishing pigs (initial body weight 51.49 ± 1.12 kg) were randomly allocated into 2 treatment groups, control group, and 0.2% Trp group. The control group was fed the basal diet, and 0.2% Trp group was fed basal diet plus 0.2% Trp. The trial period is 60 d. Compared with control group, the mRNA abundance of claudin-3 and zonula occluden-1 (ZO-1) in the jejunum in 0.2% Trp group (P < 0.05) was increased. According to immunohistochemistry and immunoblotting test, the expression of ZO-1 in jejunum in 0.2% Trp group was also significantly increased compared with the control group (P < 0.05). These results revealed that Trp enhanced the expression of tight junction protein ZO-1 in the intestine of pig model. Trp may be potential and beneficial dietary functional factor for regulating the intestinal development and inhibiting intestinal aging.