Comparison study between single enzyme and multienzyme complex in distiller's dred grains with soluble supplemented diet in broiler chicken

Upregulation of the nutritional value of feed is the major target of various studies in the livestock industry, and dietary enzyme supplementation could aid in digesting the nondegrading nutrients of grains in feed ingredients. Dried distillers' grains with solubles (DDGS) is a byproduct of the fermentation process in the beverage industry and can be used as a large supply source of fiber in feed. Therefore, we conducted an experiment with male broiler chickens to investigate the effect of various types of enzymes on DDGS and compare the efficacy of single enzyme and multienzyme complexes on growth performance and gut environments in broiler chickens. We used 420 1-day-old broiler chickens (Ross 308), and they were allotted into 4 dietary treatments with seven replications (CON, corn-soybean meal [SBM] diet; NC, DDGS supplemented diet; SE, 0.05 % of mannanase supplemented DDGS-based diet; MC, 0.10% of multienzyme complex (mannanase and xylanase, glucanase) supplemented DDGS-based diet. The dietary exogenous enzyme in the DDGS-supplemented diet could improve growth performance as much as the growth of the control group, and digestibility of dry matter, crude protein, and gross energy were significantly increased by enzyme addition in groups of chicks fed DDGS-supplementation diet. Moreover, the populations of pathogenic bacteria, coliforms, and Bacteroidetes were significantly decreased by enzyme supplementation, which might lead to improved gut mucus-secreting cells and inflammatory cytokines in the jejunum. Collectively, dietary single enzyme and multienzyme complexes could improve gut environments, including intestinal immune responses and gut microbial population, and lead to improvement of growth performance in broiler chickens.

Dietary effects of melatonin on growth performance by modulation of protein bioavailability and behavior in early weaned rats and pigs

Melatonin, which is produced from tryptophan, exerts various biological functions, including the regulation of circadian rhythm, sedative agents, and antioxidant ability. Therefore, we conducted two experiments with early-weaned rats and pigs to investigate the antioxidant and sedative effects of melatonin. In the rat experiment, a total of 42 rats (21 days old) were used, and the antioxidant capacity was determined. Next, we used 120 early-weaned piglets (21 days old) to conduct a 5-week experiment to evaluate the reductive effect of melatonin on energy-wasting movement, including roaming and fight states. Dietary melatonin supplementation significantly improved growth in both rats and pigs compared to the control groups. Additionally, rats fed a melatonin-supplemented diet showed advanced antioxidant capacity with a decrease in hepatic malondialdehyde concentration compared to rats fed a basal diet. Moreover, dietary melatonin ingestion increased resting and feeding behaviors and reduced roaming and fight behaviors during Days 8-21 compared to the control diet group. Collectively, early weaned animals given dietary melatonin supplementation showed improved growth through upregulation of hepatic antioxidant capacity and minimization of energy-wasting behavior, including roaming and fight states, after pigs' social hierarchy establishment.

Dietary effects of sophorolipids on nutrient bioavailability and intestinal microenvironments in broiler chickens

Using antibiotics as growth promoter has been banned in poultry feed industry, thus various researchers try to seek an alternative to replace the growth-promoting antibiotics. In this study, we aimed to evaluate the growth performance via intestinal nutrient utilization and cecal microbial composition of broiler after dietary supplementation with most commonly using antibiotics, zinc bacitracin, and sophorolipid. A total of 180 1-day-old chicks were randomly assigned, and dietary treatment was as follow: CON, basal diet; ZB, 100 ppm of zinc bacitracin supplemented diet; and SPL, 250 ppm of sophorolipid supplemented diet. Their growth performance was evaluated and the samples of blood, small intestine, and ileal and cecal digesta were collected for biochemical, histological, and genomic analyses. The body weight and average daily gain of 7-day-old chicks were higher in ZB and those in overall experimental period were improved by ZB and SPL supplementation (p < 0.05). Their intestinal characteristics were not affected by dietary treatments in duodenum and ileum. Nonetheless, villus height was increased by SPL supplementation in jejunum (p < 0.05). Moreover, dietary SPL supplementation could down-regulate the expression level of pro-inflammatory cytokine, IL-1β (p < 0.05). mRNA levels of lipid and protein transporters did not differ among the treatments, however, relative expression levels of carbohydrate transporters, GLUT2 and SGLT1 were increased in broiler chicken's jejumum fed zinc bacitracin and sophorolipid supplemented diets (p < 0.05). Dietary zinc bacitracin supplementation could increase the population of Firmicutes in phylum level, and the portion of Turiciacter in genus level. On the other hands, the portion of Faecalibacterium was increased by dietary SPL supplementation compared to the other treatments. Our findings suggest that SPL supplementation improves growth performance through enhanced carbohydrate utilization capacity via improvement of gut morphological status and modulation of the cecal microbial population of broilers.

Effects of Sophorolipid on Growth Performance, Organ Characteristics, Lipid Digestion Markers, and Gut Functionality and Integrity in Broiler Chickens

Simple Summary

Availability of dietary fat and oil is important to broiler chicken due to their rapid growth rate. Therefore, we conducted an experiment with dietary sophorolipid, a glycolipid-type emulsifier, to investigate growth, lipid digestion markers and gut health during the growing period. Growth was accelerated by dietary sophorolipid supplementation through upregulation of lipid digestion and absorption markers. Additionally, dietary sophorolipid also increased the surface area of the gut and modulated microbial population and short-chain fatty acid concentration. Collectively, this study proposed that sophorolipid addition in feed could enhance chicken’s growth by increased intestinal absorption of dietary lipid and improved gut microenvironments.

Abstract

Dietary fat and oil could aid in reaching the high-energy requirements of fast-growing birds; however, these inclusions could lead to nutrient waste. This is because young birds have limited lipid digestion due to the low secretion of lipase and bile salt. Sophorolipid (SPL), a glycolipid emulsifier with lower toxicity and higher biodegradability, can upregulate fat utilization by increasing digestibility. Accordingly, a five-week-long experiment was conducted with 720 one-day-old chicks (Ross 308) to investigate the effects of dietary SPL on growth, organ characteristics, and gut health. The allotment was partitioned into four treatment groups according to their body weight with six replications (30 chick/pen). The three treatment diets comprised a basal diet with a formulation that met the Ross 308 standard and 5, 10, and 15 ppm SPL in the basal diet. During the experiment, the birds had free access to feed, and body weight and feed intake were measured at the end of each phase. Chickens were put down at the end of the growing and finishing phases, and jejunum and cecal samples were obtained to investigate organ characteristics and gut environments. The data were analyzed using the generalized linear model procedures of SAS 9.4, and all data were assessed for linear, quadratic, and cubic effects of dietary SPL-supplemented dosages. Body weight was significantly increased with 10 ppm of SPL supplementation in the grower phase without affecting feed efficiency. The relative weights of the intestine and the bursa of Fabricius were quadratically decreased by SPL supplementation with a lower population of Streptococcus and higher propionate and butyrate concentrations. Additionally, the dietary SPL supplementation groups showed a significantly increased villus/crypt ratio with higher intestinal expression levels of fatty acid translocase, diacylglycerol acyltransferase 2, and fatty acid transporter 4. Collectively, proper SPL supplementation in the chicken diet could improve growth performance by down-regulating immune modulation and up-regulating lipid digestion and absorption via modulation of gut microenvironments.

Protective and restorative effects of sophorolipid on intestinal dystrophy in dextran sulfate sodium-induced colitis mouse model

The public has gradually begun to regard inflammatory bowel disease (IBD) as a crucial health issue; however, its mode of action has not been fully elucidated. Sophorolipid (SPL), a glycolipid-type biosurfactant, could be used as a potential treatment in physical intestinal dystrophy. We conducted a 2 × 2 factorial experiment to investigate the protective effect of SPL in a dextran sulfate sodium (DSS)-induced colitis mouse model (first factor, presence of SPL in feed; second factor, presence of DSS in water). Forty C57BL/6 mice (8-week-old) were used, and they were allocated to treatments according to their initial body weight. After a 7 d adjustment period, the DSS treatment was initiated in specific groups. At day 14, DSS was withdrawn from mice, and half of the mice were randomly selected and euthanized to collect colon and colon content samples. Three days after the end of DSS treatment, the rest of the mice were euthanized to investigate the therapeutic effect of SPL. Dietary SPL improved the growth performance in 3 d after DSS treatment, and the histopathological score was lower in the DSS-treated SPL group than in the DSS-treated control group. Mucosal thickness and goblet cell numbers significantly increased in the SPL-supplemented groups compared to in the control group. Similarly, SPL supplementation upregulated the gene expression levels of mucin-2, interleukin-10, and transforming growth factor-β, and increased the concentration of short chain fatty acid compared to the control groups. In conclusion, dietary supplementation with SPL attenuated the pathological response against acute and chronic inflammation by the maintenance of the mucosal barrier and wound healing capacity.

Sophorolipid protects against early-weaning syndrome by improving the gut microenvironment in early-weaned piglets

Background

In animals, weaning stress is the first and most critical stress. Weaning can negatively affect the growth performance of animals physically, psychologically, and pathologically. Our previous studies on the HT-29 cell line and early-weaned rats demonstrated that adequate sophorolipid (SPL) supplementation in feed could enhance the mucin-producing and wound healing capacities of the gut defense system by modulating gut microbiota.

Methods

We conducted an experiment with one hundred forty 21-day-old early weaned piglets (L x Y x D). They were allocated into 4 treatment and 7 replications (4 pigs per pen) according to their initial body weight. Body weight and feed intake were measured biweekly during experimental period. After 6 weeks, 28 pigs were randomly selected and sacrificed to collect plasma, jejunum, and cecal content samples.

Results

Dietary SPL supplementation at 5 and 10 mg/kg quadratically increased the average daily gain during the experimental period in the treatment groups when compared with the control group. The albumin levels of piglets fed with the SPL supplemented diet were downregulated to the normal range. Moreover, in feed, SPL supplementation at 5 and 10 mg/kg improved jejunal histological indices and gene expression levels related to mucin secretion and local inflammation markers. Consistent with these results, adequate SPL supplementation (5 and 10 mg/kg) increased the population of Prevotella, a beneficial bacterium, and its short-chain fatty acid production in the ceca of piglets.

Conclusions

The occurrence of diarrhea after weaning in piglets could be reduced by feeding a 10 ppm of SPL supplemented diet which improves the gut defense system by improving the microbial population and enhancing mucin layer integrity.

Dietary sophorolipid accelerates growth by modulation of gut microbiota population and intestinal environments in broiler chickens

BACKGROUND

Gut is a crucial organ for the host's defense system due to its filtering action of the intestinal membrane from hazardous foreign substances. One strategy to strengthen the gut epithelial barrier function is to upregulate beneficial microflora populations and their metabolites. Sophorolipid (SPL), which is a glycolipid bio-surfactant, could increase beneficial microflora and decrease pathogenic bacteria in the gastrointestinal tract. Therefore, herein, we conducted an experiment with broiler chickens to investigate the fortifying effects of SPL on the host's gut defense system by modulating the microbiota population.

METHODS

A total of 540 1-day-old chicks (Ross 308) were used, and they were immediately allotted into three treatment groups (6 replications with 30 chicks/pen) according to their initial body weight. The dietary treatments consisted of CON (basal diet), BAM (10 mg/kg bambermycin), and SPL (10 mg/kg SPL). During the experiment, birds freely accessed feed and water, and body weight and feed intake were measured at the end of each phase. On d 35, birds (one bird/pen) were sacrificed to collect jejunum and cecum samples.

RESULTS

Dietary SPL and BAM supplementation significantly accelerated birds' growth and also significantly improved feed efficiency compared to CON. Intestinal microbial community was significantly separated by dietary SPL supplementation from that of CON, and dietary SPL supplementation significantly increased Lactobacillus spp. and Akkermansia muciniphila. Moreover, birds fed with dietary SPL also showed the highest concentration of cecal butyrate among all treatment groups. Gut morphological analysis showed that dietary SPL significantly increased villus height, ratio of villus height to crypt depth, goblet cell numbers, and the gene expression levels of claudin-1 and mucin 2. Additionally, dietary SPL significantly decreased the mRNA expression level of pro-inflammatory cytokine, interleukin-6, and increased that of anti-inflammatory cytokine, interleukin-10, compared to other treatments.

CONCLUSIONS

Dietary SPL increases the beneficial bacterial population and butyrate concentration, which leads to a strengthened gut barrier function. In addition, the intestinal inflammation was also downregulated by dietary SPL supplementation.

Curative effects of sophorolipid on physical wounds: In vitro and in vivo studies

Early‐weaning syndrome is harmful to animals because an effect on growth in the early‐stage of life generally determines the overall growth rate. Sophorolipid (SPL), a surface‐active glycolipid compound, has been shown to exhibit antimicrobial activity and stimulate cell proliferation. Thus, in vitro and in vivo studies were conducted to evaluate the potential of SPL on the gut turnover after the wound. The in vitro experiment with HT‐29 cells showed the increased proliferation with increasing gene levels of collagenase‐1 and matrilysin‐1. Next, the 16‐day in vivo experiment was conducted with thirty rats (14‐day‐old), and the allocation was performed according to their body weight (BW) into three treatments: control diet (CON), 48 ppm of oxytetracycline‐supplemented diet (OTC) and 10 ppm of SPL‐supplemented diet (SPL). Dietary SPL accelerates the growth of rats in overall periods, and intestinal permeability was lower in SPL at day 16. Villus:crypt ratio and the goblet cell count were also higher in SPL than in CON at day 8. Caecal Streptococcus spp. were significantly reduced with dietary SPL and OTC at day 8 and 16, and total short‐chain fatty acid, acetate and butyrate levels were increased in the SPL at day 8. In conclusion, these data demonstrated that SPL could improve gut remodelling potential and modulate the gut environments, resulted in acceleration of post‐weaning growth. Therefore, SPL could have a potential as a feed additive aimed at promoting repair system after wound in animal's gut.

Dietary Whey Protein Supplementation Increases Immunoglobulin G Production by Affecting Helper T Cell Populations after Antigen Exposure

Whey protein is a by-product of cheese and casein manufacturing processes. It contains highly bioactive molecules, such as epidermal growth factor, colony-stimulating factor, transforming growth factor-α and -β, insulin-like growth factor, and fibroblast growth factor. Effects of whey protein on immune responses after antigen (hemagglutinin peptide) injection were evaluated in rats. Experimental diets were formulated based on NIH-31M and supplemented with 1% amino acids mixture (CON) or 1% whey protein concentrate (WPC) to generate isocaloric and isonitrogenous diets. Rats were fed the experimental diets for two weeks and then exposed to antigen two times (Days 0 and 14). Blood was collected on Days 0, 7, 14, and 21 for hematological analysis. The WPC group showed decreased IgA and cytotoxic T cells before the antigen injection (Day 0) but increased IgG, IL-2, and IL-4 after antigen injection due to increased B cells and T cells. Helper T cells were increased at Days 14 and 21, but cytotoxic T cells were not affected by WPC. WPC may activate adaptive immunity (IgG) against antigen by modulating helper T cells. Bioactive molecules might contribute to the immune-enhancing effects of whey protein concentrate.

Association between the body weight of growing pigs and the functional capacity of their gut microbiota

Gastrointestinal microbiota impact host's biological activities, including digestion of indigestible feed components, energy harvest, and immunity. In this study, fecal microbiota of high body weight (HW) and low body weight (LW) growing pigs at 103 days of age were compared. Principal coordinates analysis separated the HW and LW groups into two clusters, indicating their potential differences between microbial community composition. Although the abundances of two major phyla, Firmicutes and Bacteroidetes, did not significantly differ between the HW and LW groups, some genera showed significant differences. Among them, Peptococcus and Eubacterium exhibited strong positive correlations with body weight (BW) and average daily gain (ADG) (Rho > 0.40), whereas Treponema, Desulfovibrio, Parabacteroides, and Ruminococcaceae_unclassified exhibited strong negative correlations with BW and ADG (Rho < -0.40). Based on these results, the structure of intestinal microbiota may affect growth traits in pigs through host-microbe interactions. Further in-depth studies will provide insights into how best to reshape host-microbe interactions in pigs and other animals as well.

Exposure to etoxazole induces mitochondria-mediated apoptosis in porcine trophectoderm and uterine luminal epithelial cells

Etoxazole is an organofluorine insecticide widely used in agriculture. Exposure to insecticides is a serious environmental problem owing to their cytotoxic effects in humans and animals. Reproductive toxicity of various organofluorine insecticides have been shown in previous studies. However, few studies have evaluated the toxicity of etoxazole in mammals. We aimed to examine the toxic effects of etoxazole in porcine trophectoderm (pTr) and uterine luminal epithelial (pLE) cells. To estimate the effects of etoxazole, we conducted assays after treatment with multiple concentration of etoxazole (0, 2, 4, 6 and 9 μM) to pTr and pLE cells for 0-72 h. Etoxazole decreased the cell proliferation, viability, and migration of pTr and pLE cells. Further, etoxazole induced apoptosis via cell cycle arrest and disruption of mitochondrial membrane potential. We also found that pro-apoptotic proteins and endoplasmic reticulum (ER) stress-response proteins were activated in response to etoxazole. Finally, we observed that etoxazole altered the PI3K/AKT and MAPK signaling pathways and the mRNA expression of genes associated with implantation. Collectively, these results suggest that etoxazole disrupts normal cellular physiology and might cause early implantation failure.

Butylated hydroxytoluene induces dysregulation of calcium homeostasis and endoplasmic reticulum stress resulting in mouse Leydig cell death

Butylated hydroxytoluene (BHT) is a synthetic phenolic antioxidant that has been used as an additive for fat- or oil-containing foods. The exposure index value increases with extended usage of the chemical. Further, estimated total amount of BHT could exceed standard regulation, considering dietary intake or another exposure. Although BHT may induce side effects in reproductive systems, adequate research had not yet been performed to confirm them. In this study, we investigated the effects of BHT on mouse Leydig cells (TM3), which are components of testis. Our results indicated that BHT suppressed cellular proliferation and induced cell cycle arrest in TM3 cells. Moreover, BHT hampered cytosolic and mitochondrial calcium homeostasis in TM3 cells. Furthermore, BHT treatment led to endoplasmic reticulum (ER) stress and DNA fragmentation, simultaneously stimulating intrinsic apoptosis signal transduction. To elucidate the mode of action of BHT on Leydig cells, we performed western blot analysis and confirmed the activation of the PI3K/AKT and MAPK pathways. Collectively, our results demonstrated that BHT has toxic effects on mouse Leydig cells via induction of calcium dysregulation and ER-mitochondria dysfunction.

PSVIII-33 Therapeutic effects of sophorolipid on intestinal restoration in HT-29 cell and early-weaned rats

Sophorolipid (SPL) is a glycolipid bio-surfactant produced by Candida bombicola and displays antimicrobial activity and stimulates collagenesis with less toxic and more biodegradable than other surfactants. As its effect has not been demonstrated in weaning animal models, we conducted two experiments to investigate the effect of SPL on intestinal restoration. First, a wound healing assay using HT-29 cells was conducted to quantify migration capacity. Cells were seeded into 6-well plate and scratched. After 24- and 48-hour incubation, SPL increased migration of cells in a dose-dependent manner (P &lt; 0.05). It seemed that SPL had restorative effects on intestinal wounds. Afterwards, an in vivo experiment was conducted using thirty 2-week-old early-weaned rats, which were randomly allotted into three treatments (CON; NIH-31 diet, BAM; 32 ppm of bambermycin and SPL; 10 ppm of SPL). During 16 days of trial, rats fed ad libitum and body weights were measured every four days. Rat were sacrificed at days 8 and 16 to collect jejunum to investigate morphological changes and cecal contents to determine microbial population. The data were analyzed using ANOVA procedures of SAS 9.4. The means were compared by Duncan’s multi-range test at P &lt; 0.05 level of significance. Rats in SPL were heavier than those in CON by 15.1 % at day 16. Jejunal villus height in SPL was highest among treatments at day 8, and it was also significantly lengthened in SPL than other treatments at day 16 (P &lt; 0.05). Cecal populations of E. coli, Streptococcus spp. and Salmonella spp. were significantly reduced by 64.7 %, 67.2 % and 40.0 % in SPL, respectively, relative to CON at day 16 (P &lt; 0.05). Collectively, SPL accelerated growth by improving intestinal restoration and modulating microbiota population. SPL might have a potential as a feed additive to reduce early-weaning stress of livestock animals.

PSIX-19 Effects of ValiMP® supplementation on growth performance, carcass characteristics, and pork quality in growing-finishing pigs

ValiMP® is a mixture of phytochemical compounds containing manganese. An experiment was carried out to evaluate the effects of ValiMP® on growth performance, carcass characteristics, and pork quality in growing-finishing pigs. The trial was conducted in a 2x3 factorial design with two levels of CP (LP, 15% or HP, 16%), and three types of supplements (Control; 10 ppm ractopamine; or 0.25% ValiMP®). Dietary treatments were: LC (Low CP+control), LR (Low CP+ractopamine), LV (Low CP+ValiMP®), HC (High CP+control), HR (High CP+ractopamine), HV (High CP+ValiMP®). A total of 144 growing pigs at 50 kg initial body weight (BW) were allotted and fed one of the experimental diets for 70 days. But ractopamine in LR and HR treatments was supplemented during the last 35 days. BW and feed intake were measured weekly, and pork quality was determined in longissimus dorsi muscle. All values were statistically analyzed using ANOVA procedure of SAS 9.4 software and differences at P &lt; 0.05 level were considered significantly different. Results showed dietary ractopamine or ValiMP® supplementation numerically promoted growth performance compared to control in HP treatments, although the extent was lesser in ValiMP® treatment. Ractopamine or ValiMP® also improved carcass composition in HP compared to LP. Lean percentage in HR was higher than in LR by 4.3%, and it was greater in HV than in LV by 5.9%, (P &lt; 0.05). These changes occurred at the expense of fat percentage (P &lt; 0.05). Among pork quality criteria, water-holding capacity determined by filter-paper fluid uptake method was significantly lower in HV than those in HC and HR (P &lt; 0.05). Warner-Bratzler shear force, an indicative for meat tenderness, exhibited lower values in HV and HC than that in HR (P &lt; 0.05). Overall, our results suggest ValiMP® improves growth performance and carcass composition with lesser extent to ractopamine, and pork quality more than ractopamine.

Mitigation of ER-stress and inflammation by chemokine (C-C motif) ligand 21 during early pregnancy

The immune system plays an important role in pregnancy. Chemokines recruit leukocytes at the maternal-fetal interface during early pregnancy. However, the role of the chemokine, C-C motif chemokine ligand 21 (CCL21), is less known. The aim of this study was to identify the expression of CCL21 and its receptor, CCR7, in the endometrium during estrous cycle and early pregnancy, and to investigate the functional effects of CCL21 on porcine trophectoderm (pTr) and porcine uterine luminal epithelial (pLE) cells. Our results indicated that CCL21 and CCR7 are increased in the glandular (GE) and luminal epithelium (LE) of the endometrium during early pregnancy, compared to estrous pigs. Recombinant CCL21 improved pTr and pLE cell proliferation through activation of the PI3K and MAPK pathways and suppression of tunicamycin-induced endoplasmic reticulum (ER) stress or LPS-induced inflammation. Collectively, these results provide novel insights into CCL21-mediated signaling mechanisms at the maternal-fetal interface during early pregnancy.

4,4'-Dichlorodiphenyltrichloroethane (DDT) and 4,4'-dichlorodiphenyldichloroethylene (DDE) inhibit myogenesis in C2C12 myoblasts

BACKGROUND

Most countries have banned the use of 4,4'-dichlorodiphenyltrichloroethane (DDT). However, owing to its extremely high lipophilic characteristics, DDT and its metabolite 4,4'-dichlorodiphenyldichloroethylene (DDE) are ubiquitous in the environment and in many types of food. The positive correlation between exposure to insecticides, including DDT and DDE, and weight gain, resulting in impaired energy metabolism in offspring following perinatal DDT and DDE exposure, was previously reported. Therefore the influence of DDT and DDE on myogenesis using C2C12 myoblasts was investigated in this study.

RESULTS

DDT and DDE decreased myotube formation dose- and time-dependently. Among myogenic regulatory factors, DDT and DDE mainly decreased MyoD1 and Myf5 expression. DDT and DDE treatment also altered Myostatin expression, phosphorylation of protein kinase B, p70 ribosomal protein S6 kinase, forkhead box O protein 3 and mammalian target of rapamycin, resulting in attenuation of myotube formation.

CONCLUSION

These results may have significant implications for understanding the effects of developmental exposure of DDT and DDE on myogenesis and development of obesity and type 2 diabetes later in life. © 2017 Society of Chemical Industry.

Influences of quorum-quenching probiotic bacteria on the gut microbial community and immune function in weaning pigs

The aim of this study is to investigate the dynamic gut microbial diversity in weaning swine after administering feed supplemented with probiotic bacteria that specifically inhibit the activity of quorum molecules. Initially, the universal quorum molecule autoinducer-2 (AI-2) bioassay results indicated that AI-2 activity was profoundly inhibited in enterohemorrhagic Escherichia coli (EHEC) O157:H7 in the presence of Lactobacillus acidophilus strain 30SC cell extract, although the growth of EHEC was not affected. Based on plate counting results, bacterial community analysis revealed a specific reduction in coliforms compared to the control, whereas the population of lactobacilli increased in weaning swine in in vivo trials. Supplementation with L. acidophilus strain 30SC did not affect the counts of other communities, such as total aerobes and yeast/mold. In addition, PCR-denaturing gradient gel electrophoresis analysis showed a significant difference in the 16S rRNA gene products after administering L. acidophilus strain 30SC. Selected bands were sequenced, and most of them were identified as uncultured bacterium clones or a Lactobacillus- and Bifidobacterium-specific community. Therefore, our results indicate that quorum-quenching probiotic bacteria can significantly modulate the gut microbiota of swine and these beneficial effects can contribute to the improvement of performance and health in the gastrointestinal tract of weaning pigs.

Cortisone and dexamethasone inhibit myogenesis by modulating the AKT/mTOR signaling pathway in C2C12

Myogenesis occurs in both the prenatal and postnatal periods and the prenatal myogenesis is related to the postnatal myogenesis and the incidence of disease later in life. Glucocorticoids used as therapeutic agents for many diseases, but cause adverse effects on muscle homeostasis, including defects in fetal muscle development. The action of glucocorticoids on differentiated skeletal muscle was well studied, but their effects on myotube formation have not been well investigated. Dexamethasone (DEX) and cortisone (COR), two synthetic therapeutic glucocorticoids, suppress myotube formation in C2C12 cells. Both COR and DEX attenuated myotube formation through modulation of myogenic regulatory factors. In addition, they affected the IGF/PI3K/AKT/mTOR signaling pathway, resulting in increased proteolytic protein (atrogin-1 and MURF1) for muscle degradation and decreased ribosomal S6 phosphorylation. The current results conclude that COR and DEX inhibit myotube formation in C2C12 cells by modulating both the myogenic program via MRFs and protein metabolism via IGF/PI3K/AKT/mTOR signaling pathway.

4,4'-Dichlorodiphenyltrichloroethane (DDT) and 4,4'-dichlorodiphenyldichloroethylene (DDE) promote adipogenesis in 3T3-L1 adipocyte cell culture

4,4'-Dichlorodiphenyltrichloroethane (DDT), a chlorinated hydrocarbon insecticide, was extensively used in the 1940s and 1950s. DDT is mainly metabolically converted into 4,4'-dichlorodiphenyldichloroethylene (DDE). Even though most countries banned DDT in the 1970s, due to the highly lipophilic nature and very stable characteristics, DDT and its metabolites are present ubiquitously in the environment, including food. Recently, there are publications on relationships between exposure to insecticides, including DDT and DDE, and weight gain and altered glucose homeostasis. However, there are limited reports regarding DDT or DDE and adipogenesis, thus we investigated effects of DDT and DDE on adipogenesis using 3T3-L1 adipocytes. Treatment of DDT or DDE resulted in increased lipid accumulation accompanied by increased expression of CCAAT/enhancer-binding protein α (C/EBPα), peroxisome-proliferator activated receptor-γ (PPARγ), fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), adipose triglyceride lipase, and leptin. Moreover, treatment of DDT or DDE increased protein levels of C/EBPα, PPARγ, AMP-activated protein kinase-α (AMPKα), and ACC, while significant decrease of phosphorylated forms of AMPKα and ACC were observed. These finding suggest that increased lipid accumulation caused by DDT and DDE may mediate AMPKα pathway in 3T3-L1 adipocytes.

Impact of Conjugated Linoleic Acid (CLA) on Skeletal Muscle Metabolism

Conjugated linoleic acid (CLA) has garnered special attention as a food bioactive compound that prevents and attenuates obesity. Although most studies on the effects of CLA on obesity have focused on the reduction of body fat, a number of studies have demonstrated that CLA also increases lean body mass and enhances physical performances. It has been suggested that these effects may be due in part to physiological changes in the skeletal muscle, such as changes in the muscle fiber type transformation, alteration of the intracellular signaling pathways in muscle metabolism, or energy metabolism. However, the mode of action for CLA in muscle metabolism is not completely understood. The purpose of this review is to summarize the current knowledge of the effects of CLA on skeletal muscle metabolism. Given that CLA not only reduces body fat, but also improves lean mass, there is great potential for the use of CLA to improve muscle metabolism, which would have a significant health impact.

Whey Protein Concentrate Hydrolysate Prevents Bone Loss in Ovariectomized Rats

Milk is known as a safe food and contains easily absorbable minerals and proteins, including whey protein, which has demonstrated antiosteoporotic effects on ovariectomized rats. This study evaluated the antiosteoporotic effect of whey protein concentrate hydrolysate (WPCH) digested with fungal protease and whey protein concentrate (WPC). Two experiments were conducted to determine (1) efficacy of WPCH and WPC and (2) dose-dependent impact of WPCH in ovariectomized rats (10 weeks old). In Experiment I, ovariectomized rats (n=45) were allotted into three dietary treatments of 10 g/kg diet of WPC, 10 g/kg diet of WPCH, and a control diet. In Experiment II, ovariectomized rats (n=60) were fed four different diets (0, 10, 20, and 40 g/kg of WPCH). In both experiments, sham-operated rats (n=15) were also fed a control diet containing the same amount of amino acids and minerals as dietary treatments. After 6 weeks, dietary WPCH prevented loss of bone, physical properties, mineral density, and mineral content, and improved breaking strength of femurs, with similar effect to WPC. The bone resorption enzyme activity (tartrate resistance acid phosphatase) in tibia epiphysis decreased in response to WPCH supplementation, while bone formation enzyme activity (alkaline phosphatase) was unaffected by ovariectomy and dietary treatment. Bone properties and strength increased as the dietary WPCH level increased (10 and 20 g/kg), but there was no difference between the 20 and 40 g/kg treatment. WPCH and WPC supplementation ameliorated bone loss induced by ovariectomy in rats.

Inhibition of Escherichia coli O157:H7 attachment by interactions between lactic acid bacteria and intestinal epithelial cells

The intestinal epithelial cell (IEC) layer of the intestinal tract makes direct contact with a number of microbiota communities, including bacteria known to have deleterious health effects. IECs possess innate protective strategies against pathogenic challenge, which primarily involve the formation of a physicochemical barrier. Intestinal tract mucins are principal components of the mucus layer on epithelial surfaces, and perform a protective function against microbial damage. However, little is currently known regarding the interactions between probiotics/pathogens and epithelial cell mucins. The principal objective of this study was to determine the effects of Lactobacillus on the upregulation of MUC2 mucin and the subsequent inhibition of E. coli O157:H7 attachment to epithelial cells. In the current study, the attachment of E. coli O157:H7 to HT-29 intestinal epithelial cells was inhibited significantly by L. acidophilus A4 and its cell extracts. It is also important to note that the expression of MUC2 mucin was increased as the result of the addition of L. acidophilus A4 cell extracts (10.0 mg/ml), which also induced a significant reduction in the degree to which E. coli O157:H7 attached to epithelial cells. In addition, the mRNA levels of IL-8, IL-1beta, and TNF-alpha in HT-29 cells were significantly induced by treatment with L. acidophilus A4 extracts. These results indicate that MUC2 mucin and cytokines are important regulatory factors in the immune systems of the gut, and that selected lactobacilli may be able to induce the upregulation of MUC2 mucin and specific cytokines, thereby inhibiting the attachment of E. coli O157:H7.

Rapid identification of Lactobacillus acidophilus by restriction analysis of the 16S-23S rRNA intergenic spacer region and flanking 23S rRNA gene

A rapid molecular approach was developed for the initial identification of Lactobacillus acidophilus strains which are difficult to identify using a single biochemical test. The 16S-23S rRNA intergenic spacer regions and flanking 23S rRNA genes of 19 strains of lactobacilli were amplified and the nucleotide sequences and restriction site polymorphisms were analyzed. AluI was the most useful of the restriction enzymes analyzed and produced reproducible digestion profiles in the L. helveticus, L. plantarum, and L. casei groups, as well as in L. acidophilus. This restriction fragment length polymorphism method may be useful for the identification of L. acidophilus strains in dairy products.

Effects of protein deprivation on subsequent growth performance, gain of body components, and protein requirements in growing pigs

Forty-eight barrows were used in a 2 x 6 factorial arrangement to test a hypothesis that feeding a protein-deficient diet affects subsequent growth response by altering the efficiency of protein utilization. Barrows were individually fed either a 9% crude protein (CP) diet or an 18% CP diet from 20 to 30 kg of body weight (BW) (depletion phase). From 30 to 45 kg BW (realimentation phase), pigs were fed one of six experimental diets with CP levels of 11.8, 13.1, 14.3, 15.6, 18.8, and 21.8%. Four pigs were slaughtered at 20 kg BW to determine initial body composition. Four pigs from each treatment in depletion phase (a total of eight) were slaughtered at 30 kg BW, and all pigs from each treatment in realimentation phase (a total of 36) were slaughtered at 45 kg BW for subsequent compositional analysis. Pigs were bled at 20, 30, and 40 kg BW for blood urea nitrogen (BUN), insulin-like growth factor (IGF)-I, and IGF-binding protein (IGFBP) assays. Pigs were given three times the maintenance digestible energy requirement (3 x 120 kcal BW(-0.75) x d(-1)) in three equal meals daily. The feed allowance was adjusted every 3 d. During the depletion phase, pigs fed the 18% CP diet grew faster and more efficiently (P < 0.01) and gained more (P < 0.01) water and protein than did pigs fed the 9% CP diet. Pigs fed the 18% CP diet showed higher (P < 0.01) BUN values, IGF-I concentrations, and IGFBP ratios than pigs fed the 9% CP diet. During the realimentation phase, pigs fed the 9% CP diet during the depletion phase grew faster (P < 0.05), tended to grow more efficiently (P = 0.066), gained more water (P < 0.01), and tended to gain more protein (P = 0.068) than pigs fed the 18% CP diet during the depletion phase. Pigs fed the 9% CP diet during the depletion phase tended (P = 0.069) to have a higher protein requirement during the realimentation phase than pigs fed the 18% CP diet during the depletion phase. When measured at 40 kg BW, pigs fed the 9% CP diet had a lower (P < 0.05) BUN than pigs fed the 18% CP diet during the depletion phase. However, the plasma IGF-I concentration and IGFBP ratio at 40 kg BW were not affected by dietary CP level fed during the depletion phase. This study indicates that pigs fed a protein-deficient diet exhibit compensatory growth. During the period of compensatory growth, the requirement of CP for those pigs is higher than that of pigs previously fed an adequate diet. This study also suggests BUN can be used as an indicator of protein utilization efficiency and compensatory growth.

Effect of starter feeding program on growth performance and gains of body components from weaning to market weight in swine

Three experiments were conducted to test the hypothesis that different starter feeding programs (High, high quality; Low, low quality) will affect growth performance and body composition of pigs from weaning to market weight and that this effect may be influenced by gender (barrows or gilts) and breed (F, Yorkshire-Duroc x Hampshire; P, PIC Camborough 15 x PIC line 405). In Exp. 1, 21 +/- 4-d-weaned F pigs (n = 90) were used in a 2 (High or Low) x 2 (barrows or gilts) factorial design. In Exp. 2, 21 +/- 3-d-weaned pigs (n = 184) were used in a 2 (F or P) x 2 (High or Low) x 2 (barrows or gilts) factorial design. In Exp. 3, 21 F pigs from each gender and feeding program treatment were killed at d 0, 3, 7, 14, 42, 82, or 152 postweaning for evaluating body composition. Two starter feeding programs (High or Low) were applied to pigs for 6 wk postweaning. Pigs from both High and Low treatments were provided the same corn-soybean meal-based diets for the growing and finishing periods. Although the ADG of all pigs receiving the High treatment during the early starter period were higher (P < .01) than those of the Low, the terminal BW of F barrows were similar between High and Low (Exp. 1 and 2) and those of gilts were similar between High and Low (Exp. 2) (P > .80). However, the BW of P pigs receiving the High treatment, regardless of gender, tended to be heavier than those receiving the Low (Exp. 2) and F barrows receiving the High treatment tended to be heavier than those receiving the Low (Exp. 1). For the first 7 d postweaning, the High-fed pigs gained more protein (P < .05) and lost less fat (P < .05) than Low-fed pigs. During the growing-finishing period, the Low-fed pigs exhibited compensatory protein gain and achieved a body protein content similar (P < .60) to High-fed pigs by termination. Protein gains from weaning to termination between High- and Low-fed pigs were not different in Exp. 2 and 3. The protein gain of gilts was higher (P < .05) than that of barrows. Similarly, fat gain within genders was not affected by starter feeding program. Fat gain of gilts, however, was lower (P < .08) than that of barrows in Exp. 3. In conclusion, the nutritional quality of the starter feeding program affected growth performance immediately after weaning but did not affect protein gain over the entire production period.

Effect of feeding a milk replacer to early-weaned pigs on growth, body composition, and small intestinal morphology, compared with suckled littermates

Feeding of milk replacer to early-weaned pigs was evaluated in two experiments. In Exp. 1, 18 litters of pigs were either weaned conventionally (d 21), split-weaned and fed milk replacer plus starter diet (d 14 and 21), or weaned and fed milk replacer plus starter diet (d 21). Split weaning combined with feeding a milk replacer increased ADG 22% from d 14 and d 28 compared to conventional weaning (P < .05). Feeding a milk replacer plus starter diet after weaning increased ADG 30% between d 21 and 28 compared to conventional weaning (P < .01). In Experiment 2, four litters of 12 pigs each were divided at d 18 into six heavy and six light pigs and randomized across sow-suckled, milk replacer, or starter diet groups. After 1 wk, pigs fed milk replacer weighed 20% more (P < .001), contained 10% more protein (P < .01) and 17% more fat (P < .05), and had 74% longer villi in the proximal small intestine (P < .001) than suckled pigs. In contrast, pigs fed starter diet weighed 19% less (P < .001), contained 20% less protein and fat (P < .001), and had 28% shorter villi in the proximal small intestine (P < .05) than suckled pigs. Therefore, milk replacer feeding the 1st wk after weaning stimulates pig development, both locally in the small intestine and on a whole-body basis, most likely by an increased energy and nutrient intake. Suckling beyond 18 d postnatally inhibits pigs to reach maximal potential weight gain. In conclusion, milk replacer feeding might be beneficial to reach maximal pig weight gain at weaning.

Lactational variation and relationship to postnatal growth of insulin-like growth factor-I in mammary secretions from genetically diverse sows

Mammary secretions obtained from four groups of sows at parturition and on days 7, 14 and 21 of lactation were defatted and assayed for total protein and insulin-like growth factor-I (IGF-I). Sows (n = 57) represented two breeds (Landrace and Duroc) and two genetic lines (selected for differences in sow productivity index, SPI) within each breed. Colostrum of Duroc sows was 4-6 fold and 30-60 fold greater in protein (P less than .001) and IGF-I (P less than .001) concentrations, respectively, than the corresponding day 7 milk from these sows. In contrast, the colostrum of Landrace sows was 2-3 fold and 30-50 fold greater in protein (P less than .001) and IGF-I (P less than .001) concentrations, respectively, than the corresponding day 7 milk. The IGF-I content in milk from Duroc sows did not differ among days 7, 14 and 21 of lactation, whereas the IGF-I content of day 7 milk from Landrace sows exceeded those for the corresponding 14 day and 21 day secretion (P less than .05). IGF-I concentration in days 14 and 21 milk was higher in Duroc (P less than .001 respectively) than Landrace sows. No significant differences in total protein or IGF-I content of mammary secretions were observed between the selected and control lines within each breed.(ABSTRACT TRUNCATED AT 250 WORDS)