Extra arginine supplementation during the suckling period alleviates weaning stress through the regulation of dendritic cells and Notch2 signaling in piglets.

This study aims to study the effects of extra arginine (Arg) supplementation during the suckling period on the weaning stress and intestinal barrier function of breastfed piglets. Forty 7-day-old breastfed piglets divided into the control group (CON) and Arg group (Arg) were fed with extra saline or Arg (250 mg per kg per d body weight), respectively. All piglets were weaned when they were 21 days old. Eight piglets from each group were sacrificed before weaning and on the 3rd-day after weaning, respectively. The results showed that Arg improved the average daily weight gain of piglets before weaning (P < 0.01) and decreased the average daily weight loss after weaning (P < 0.05). Weaning decreased the ratio of the villus length versus crypt depth (V/C) in the SI (P < 0.001), while Arg increased the V/C of the jejunum (P < 0.05). Arg increased the levels of immunoglobulins in the serum and SI (P < 0.05), decreased pro-inflammatory cytokines and increased anti-inflammatory cytokines in the SI (P < 0.05). In addition, Arg supplementation increased the numbers of SWC3a+CD40+ (P < 0.01) and SWC3a+SLAII+ DCs (P < 0.05), down-regulated Notch2 expression and up-regulated Jagged1 expression in the ilea of weaning piglets (P < 0.05). In conclusion, Arg supplementation during the suckling period decreased the LDH leakage in the SI, improved the intestinal morphology, down-regulated the contents of pro-inflammatory cytokines, accelerated the accumulation of DC precursors before weaning and increased the number of mature DCs after weaning, and thus improved the growth performance and reduced the weaning stress of piglets, and this might be associated with the regulation of Notch2 signaling.

Dietary Palygorskite Clay-Adsorbed Nano-ZnO Supplementation Improves the Intestinal Barrier Function of Weanling Pigs.

This study aimed to investigate the effects of PNZ on intestinal mucosal barrier function in weaning piglets. A total of 210, 21-day-old piglets with similar body weights (6.30 ± 0.51 kg) were randomly allocated into seven groups: control group (CON), antibiotic group (ANT), ZnO group (ZO), nano-ZnO group (NZO) and low, middle, and high PNZ groups (LPNZ, MPNZ, and HPNZ). The seven groups were, respectively, fed control diets or control diets supplemented with antibiotics; 3,000 mg/kg ZnO; 800 mg/kg nano-ZnO; 700, 1,000, or 1,300 mg/kg PNZ. More integrated intestinal villi were observed in the LPNZ group. In the jejunum of LPNZ group, the crypt depth significantly decreased (P < 0.05), and the ratio of villus height to crypt depth (V/C) significantly increased (P < 0.05). In addition, the villus width and surface area of the ileum were significantly increased in the LPNZ group (P < 0.05). Dietary supplementation with PNZ can significantly increase the number of goblet cells in the mucosa of the jejunum and ileum (P < 0.05), decrease the contents of TNF-α and IL-1ß (P < 0.05), and increase the contents of sIgA and IL-4 in the jejunal and ileal mucosa (P < 0.05). Meanwhile, the mRNA expression of MCU2 and ZO1 in PNZ group were significantly increased (P < 0.05), the mRNA expression of TLR4 and MyD88 was downregulated (P < 0.05). With increasing levels of PNZ, decreased proinflammatory cytokines and increased intestinal mucosal barrier function in weaned pigs was observed. In conclusion, supplementation with PNZ could effectively improve the intestinal barrier function of weanling piglets and potentially could replace the use of high doses of ZnO and antibiotics. The appropriate dose of PNZ for supplementation was 700 mg/kg.

Early Weaning Affects Liver Antioxidant Function in Piglets.

This study examined the impact of early weaning on antioxidant function in piglets. A total of 40 Duroc × Landrace × Large White, 21-day-old piglets (half male and half female) were divided into suckling groups (SG) and weaning groups (WG). Piglets in WG were weaned at the 21st day, while the piglets in SG continued to get breastfed. Eight piglets from each group were randomly selected and slaughtered at 24th-day (SG3, WG3) and 28th-day old (SG7, WG7). The body weight, liver index, hepatocyte morphology, antioxidant enzymes activity, gene expression of antioxidant enzymes, and Nrf2 signaling in the liver of piglets were measured. The results showed that weaning caused decreased body weight (p < 0.01), lower liver weight (p < 0.01), and decreased the liver organ index (p < 0.05) of piglets. The area and size of hepatocytes in the WG group was smaller than that in the SG group (p < 0.05). We also observed that weaning reduced the activity of superoxide dismutase (SOD) and catalase (CAT) (p < 0.05) in the liver of piglets. Relative to the SG3 group, the gene expression of GSH-Px in liver of WG3 was significantly reduced (p < 0.05). The gene expression of Nrf2 in the SG3 group was higher than that in the WG3 group (p < 0.01). The gene expression of NQO1 in the SG7 group was higher than that in the WG7 group (p < 0.05). In conclusion, weaning resulted in lower weight, slowed liver development, and reduced antioxidant enzymes activity, thereby impairing liver antioxidant function and suppressing piglet growth.

Substitution of ramie (Boehmeria nivea) for alfalfa in improving the carcass and meat quality of Liuyang Black goats.

Ramie (Boehmeria nivea) is noted for the production of a large biomass that has a high protein content and is rich in antioxidants. It may thus serve as a high-quality forage material to replace alfalfa and improve the meat quality of farmed animals. In this study, we evaluated the carcass characteristics and meat quality of goats when 0, 35%, 75%, and 100% of dietary alfalfa was replaced with ramie. Crude protein content (linear, P < 0.0001) and key muscle color values at 24 h after slaughter decreased with increasing ramie levels. The content of most individual amino acids, non-essential amino acids (NEAA), total amino acids (TAA), branched chain amino acids (BCAA), functional amino acids (FAA), and flavor amino acids (DAA) decreased (P < 0.05) with increasing dietary ramie. The diet in which 35% of alfalfa was replaced with ramie yielded meat with the highest amino acid content, whereas the fatty acid profile was unaffected by the inclusion of ramie. These results indicate that ramie could be used as a potential dietary forage resource for goats, and that substituting 35% of alfalfa with ramie, which is equivalent to 126 g/kg DM content, would be optimal in terms of goat meat quality.

Illumina Sequencing and Metabolomics Analysis Reveal Thiamine Modulation of Ruminal Microbiota and Metabolome Characteristics in Goats Fed a High-Concentrate Diet.

Long-term supplementation of a high-concentrate diet enhances the accumulation of lactate and decrease in pH in goat rumen, thereby disrupting the composition of microbial community. Studies have shown that incorporation of thiamine in high-concentrate diet increases ruminal pH and decreases rumen lactate concentration. To explore the effects of thiamine supplementation with a high-concentrate diet on alteration of the whole ruminal microbiota and their metabolites, 18 mid-lactating Saanen goats were randomly fed with one of three diets: (1) control diet (CON; n = 6; concentrate:forage 30:70), (2) high-concentrate diet (HG; n = 6; concentrate:forage 70:30), and (3) high-concentrate diet with 200 mg of thiamine/kg of DMI (HGT; n = 6; concentrate:forage 70:30). The goats received experimental diets for 8 weeks. Ruminal samples were collected on the last day of the 8 weeks for 16S rRNA gene sequencing and the liquid chromatograph-mass spectrometer (LC-MS) analysis. The results revealed significant alterations of the ruminal bacterial community structure and diversity in HGT groups compared to HG groups, with an overall dominance of Bacteroidetes at the phylum level and Oribacterium (P < 0.05), Anaerobiospirillum (P < 0.01), and Fibrobacter (P < 0.01) at genus level in the HGT group. The LC-MS analysis revealed that thiamine supplementation resulted in lower levels of propionate (P < 0.05), pyruvate (P < 0.01), lactate (P < 0.05), putrescine (P < 0.05), tyramine (P < 0.05), and histamine (P < 0.01) and higher levels of acetate (P < 0.05), succinates (P < 0.01), oxaloacetic acid (P < 0.01), leucine (P < 0.01), valine (P < 0.05), linoleic acid (P < 0.05), docosahexaenoic acid (P < 0.05), and 4-phenylbutyric acid (P < 0.05) in the HGT group than in the HG group. The decrease in these compounds enhanced homeostasis in the rumen environment and suppressed epithelial inflammation. Correlation analysis revealed the potential relationships between ruminal metabolites and microbial community. These findings demonstrate that thiamine supplementation can alleviate subacute ruminal acidosis (SARA) by stabilizing the microbial community and reducing toxic unnatural compounds.

Effects of diet supplementation with rumen-protected betaine on carcass characteristics and fat deposition in growing lambs.

This study evaluated the effects of dietary rumen-protected betaine (RPB) supplementation on the fat deposition of lambs. Sixty Hu sheep were randomly divided into 5 groups. The lambs were fed a control diet (CON) or diets supplemented with 1.1 g/d unprotected betaine (UPB), 1.1 g/d RPB, 2.2 g/d RPB or 3.3 g/d RPB for 70 days. Compared with UPB, the abdominal fat in 2.2 g/d RPB supplemented group was decreased (P < .05). Compared with CON and UPB, the fat contents in longissimus dorsi (LD) of RPB treatments were increased (P < .01). With increasing of RPB levels, the fat content in the LD was quadratically increased (P < .05). Compared with CON, genes expression of PI3K, mTOR and S6K1 in the LD of RPB treatments were up-regulated (P < .05). In conclusion, RPB supplementation decreased the abdominal fat in lambs but increased the fat content in lamb meat, and this effect might be regulated by mTOR signaling.

Enterococcus faecium NCIMB 10415 supplementation improves the meat quality and antioxidant capacity of muscle of broilers.

The present study was conducted to investigate the effects of Enterococcus faecium (E. faecium) on the meat quality and antioxidant capacity of muscle in broilers. A total of 600 Arbor Acre broiler chickens (1-day-old, male) were randomly divided into five treatments with six replicates (20 chickens per replicate) for each treatment. The five treatments were the control treatment (CON, basal diet), antibiotic treatment (ANT, basal diet supplemented with 0.1% chlortetracycline) and E. faecium-supplemented treatments (LEF, MEF and HEF, basal diet supplemented with 50, 100 and 200 mg/kg of E. faecium respectively). The experiment lasted 42 days in two periods of 21 days. Results showed that there were no differences in breast meat quality among different treatments (p > 0.05). Compared with the CON and ANT treatments, the yellowness of thigh meat in E. faecium-supplemented treatments was significantly increased (p < 0.05); the shear force of thigh meat in the LEF and MEF treatments was lower than that of the CON treatment (p < 0.05). In addition, the concentration of the inosine monophosphate (IMP) in the breast and thigh meat of the MEF treatment was significantly higher than that of the other treatments (p < 0.05). At 21 days, the total antioxidant capability (T-AOC) level and glutathione peroxidase (GSH-Px) activity of breast meat and superoxide dismutase (SOD) in the thigh meat of the MEF treatment were greatly increased (p < 0.05). At 42 days of age, the catalase (CAT), GSH-Px and T-AOC activities in the breast meat of the MEF treatment were increased (p < 0.05) and the CAT activity of thigh meat in the LEF and MEF treatments was increased (p < 0.05). In conclusion, E. faecium supplementation increased the meat quality of the thigh muscle, increased the IMP content and the activities of CAT, SOD, T-AOC, and GSH-Px of muscle in broilers. Supplementation with 100 mg/kg E. faecium had the greatest effects.

Examination of the temporal and spatial dynamics of the gut microbiome in newborn piglets reveals distinct microbial communities in six intestinal segments.

Intestinal microbiota plays a crucial role in immune development and disease progression in mammals from birth onwards. The gastrointestinal tract of newborn mammals is rapidly colonized by microbes with tremendous biomass and diversity. Understanding how this complex of segmental communities evolves in different gastrointestinal sites over time has great biological significance and medical implications. However, most previous reports examining intestinal microbiota have focused on fecal samples, a strategy that overlooks the spatial microbial dynamics in different intestinal segments. Using intestinal digesta from six intestinal segments (duodenum, jejunum, ileum, cecum, colon and rectum) of newborn piglets, we herein conducted a large-scale 16S rRNA gene sequencing-based study to characterize the segmental dynamics of porcine gut microbiota at eight postnatal intervals (days 1, 7, 14, 21, 28, 35, 120 and 180). A total of 4,465 OTUs were obtained and showed that the six intestinal segments could be divided into three parts; in the duodenum-jejunum section, the most abundant genera included Lactobacillus and Bacteroides; in the ileum, Fusobacterium and Escherichia; and in the cecum-rectum section, Prevotella. Although the microbial communities of the piglets were similar among the six intestinal segments on postnatal day 1, they evolved and quickly differentiated at later intervals. An examination of time-dependent alterations in the dominant microbes revealed that the microbiome in the large intestine was very different from and much more stable than that in the small intestine. The gut microbiota in newborn piglets exhibited apparent temporal and spatial variations in different intestinal segments. The database of gut microbes in piglets could be a referable resource for future studies on mammalian gut microbiome development in early host growth phases.

The potential of ramie as forage for ruminants: Impacts on growth, digestion, ruminal fermentation, carcass characteristics and meat quality of goats.

The objective was to evaluate the effects of ramie conserved as forage supplementation on growth, digestion, and meat quality of Liuyang black castrated goats in a 60 days feedlot study. Forty-eight goats were randomly assigned to each of four treatments: 24% rice straw + 36% ramie residues silage + 40% concentrate; 24% rice straw + 36% raw ramie silage + 40% concentrate; 24% rice straw + 36% ramie residues hay + 40% concentrate; 24% rice straw + 36% raw ramie hay + 40% concentrate. There was an increased tendency for ADG in ramie hay treatment than that of ramie silage treatment (p = 0.067). There was an increase for the apparent digestibility of DM, CP, NDF, and ADF in the ramie hay treatment than that of ramie silage treatment (p ≤ 0.034). An increased tendency was found for C18:1n-9c (% of total fatty acids) in the longissimus dorsi muscle of raw ramie treatment versus ramie residues treatment (p ≤ 0.087). These results indicate that the ramie hay or raw ramie treatment had a tendency for improving the nutrient digestibility and meat quality of goats than that of ramie silage or ramie residues treatment, respectively.

Effects of Dietary l-Arginine and N-Carbamylglutamate Supplementation on Intestinal Integrity, Immune Function, and Oxidative Status in Intrauterine-Growth-Retarded Suckling Lambs.

This study investigated the effects of dietary l-arginine (Arg) and N-carbamylglutamate (NCG) supplementation on intestinal integrity, immune function, and oxidative status in intrauterine-growth-retarded (IUGR) suckling lambs. A total of 48 newborn Hu lambs of normal birth weight (CON) and IUGR were allocated randomly into four groups of 12 animals each: CON, IUGR, IUGR + 1% Arg, or IUGR + 0.1% NCG. All lambs were raised for a period of 21 days from 7 to 28 days after birth. The Arg or NCG group exhibited improved ( p < 0.05) final body weights compared to that of the IUGR group. In comparison to the IUGR lambs, the apoptotic percentage was lower ( p < 0.05) in the ileum of IUGR lambs supplemented with Arg and NCG. In addition, in comparison to IUGR, the concentrations of protein carbonyl and malondialdehyde were lower ( p < 0.05) and the reduced glutathione (GSH) concentration and ratio of GSH/oxidized glutathione were greater ( p < 0.05) in the jejunum, duodenum, and ileum of IUGR + 1% Arg or 0.1% NCG lambs. In comparison to the IUGR group, the mRNA abundance of myeloid differentiation factor 88, toll-like receptor 9, toll-like receptor 4, interleukin 6, and fuclear factor-κB was lower ( p < 0.05) and the mRNA abundance of superoxide dismutase 1, B-cell lymphoma/leukaemia 2, zonula occludens-1 (ZO-1), and occludin was greater in the ileum of the IUGR lambs supplemented with Arg or NCG. Furthermore, the protein abundance of ZO-1 and claudin-1 in the ileum was greater ( p < 0.05) in the IUGR + 1% Arg or 0.1% NCG lambs. The results show that Arg or NCG supplementation improves the growth, intestinal integrity, immune function, and oxidative status in IUGR Hu suckling lambs.

Effects of different dietary ratio of physically effective neutral detergent fiber and metabolizable glucose on rumen fermentation, blood metabolites and growth performance of 8 to 10-month-old heifers.

OBJECTIVE: The present study was undertaken to determine an optimal balance between the amount of physically effective neutral detergent fiber (peNDF) to metabolizable glucose (MG) on rumen fermentation, blood metabolites and growth performance of 8 to 10-month-old heifers. METHODS: A total of 15 healthy Holstein heifers weighing an average of 256 kg (8 month of age) were randomly assigned to three groups of five. Treatment diets consisted of the following three peNDF8.0/MG levels: 1.46 (Treatment A), 1.74 (Treatment B), and 2.08 (Treatment C). RESULTS: The results showed that the ratio of peNDF8.0/MG affected rumen fermentation, blood metabolites and growth performance of heifers. The average daily gain of heifers tended to decrease as the ratio of peNDF8.0/MG increased (p = 0.07). The concentrations of blood urea nitrogen, triglyceride, and cholesterol increased significantly (p<0.05), while the high-density lipoprotein concentration decreased (p<0.05). After feeding 2 h and 4 h, insulin concentration in Treatment A was greater than Treatment C (p<0.05). Propionate concentration had decreasing trend (p = 0.07); acetate to propionate ratio and non-glucogenic to glucogenic volatile fatty acid (NGR) increased significantly (p<0.05). In addition, the digestibility of dry matter, crude protein, neutral detergent fiber, and acid detergent fiber decreased significantly (p<0.05). CONCLUSION: The present investigation indicated that dietary peNDF8.0/MG ratio can affect the growth and development, blood metabolites, rumen fermentation and apparent digestibility of heifers, and the optimal dietary peNDF8.0/MG ratio for 8 to 10-month-old heifers in the present study was 1.46.

Effects of different dietary ratio of metabolizable glucose and metabolizable protein on growth performance, rumen fermentation, blood biochemical indices and ruminal microbiota of 8 to 10-month-old dairy heifers.

OBJECTIVE: The aim of this experiment was to evaluate the effects of different dietary ratio of metabolizable glucose (MG) to metabolizable protein (MP) on growth performance, blood metabolites, rumen fermentation parameters and the ruminal microbial community of 8 to 10-month-old heifers. METHODS: A total of 24 Holstein heifers weighing an average of 282.90 kg (8 month of age) were randomly assigned to four groups of six. The heifers were fed one of four diets of different dietary MG/MP (0.97, 1.07, 1.13, and 1.26). RESULTS: The results showed that the ratio of MG/MP affected the growth performance, blood metabolites, rumen fermentation parameters and the ruminal microbial community of heifers. The average daily gain of heifers was enhanced by increasing the ratio of MG/MP (p<0.05). The concentration of blood urea nitrogen, cholesterol, and low density lipoprotein cholesterol as well as the concentration of total volatile fatty acid in the rumen fluid of heifers decreased with the improvement in the ratio of dietary MG/MP (p<0.05). However, the relative amount of Ruminococcus albus and Butyrivibrio fibrisolvens in the rumen of heifers was increased significantly (p<0.05) when the dietary MG/MP increased. At the same time, with the improvement in dietary MG/MP, the amount of Fibrobacter succinogenes increased (p = 0.08). CONCLUSION: A diet with an optimal ratio (1.13) of MG/MP was beneficial for the improvement of growth, rumen fermentation, dietary protein and energy utilization of 8 to 10-month-old dairy heifers in this experiment.

Effects of porcine MyD88 knockdown on the expression of TLR4 pathway-related genes and proinflammatory cytokines.

As a critical adapter protein in Toll-like receptor (TLR)/Interleukin (IL)-1R signalling pathway, myeloid differentiation protein 88 (MyD88) plays an important role in immune responses and host defence against pathogens. The present study was designed to provide a foundation and an important reagent for the mechanistic study of MyD88 and its role TLR/IL-1R signalling pathways in porcine immunity. Lentivirus-mediated RNAi was used to generate a porcine PK15 cell line with a silenced MyD88 gene and quantitative real-time PCR (qPCR) and Western blotting were used to detect changes in the expression of critical genes in the Toll-like receptor 4 (TLR4) signalling pathway. ELISA was used to measure the levels of seven proinflammatory cytokines-interleukin-1ß (IL-1ß), tumour necrosis factor-α (TNF-α), IL-6, IL-8, IL-12, macrophage inflammatory protein (MIP)-1α and MIP-1ß-in cell culture supernatants after MyD88 silencing. We successfully obtained a PK15 cell line with 61% MyD88 mRNA transcript down-regulated. In PK15 cells with MyD88 silencing, the transcript levels of TLR4 and IL-1ß were significantly reduced, whereas there were no significant changes in the expression levels of cluster of differentiation antigen 14 (CD14), interferon-α (IFN-α) or TNF-α The ELISA results showed that the levels of most cytokines were not significantly changed apart from IL-8 without stimulation, which was significantly up-regulated. When cells were induced by lipopolysaccharide (LPS) (0.1 µg/ml) for 6 h, the global level of seven proinflammatory cytokines up-regulated and the level of IL-1ß, TNF-α, IL-6, IL-8 and IL-12 of Blank and negative control (NC) group up-regulated more significantly than RNAi group (P<0.05), which revealed that the MyD88 silencing could reduce the TLR4 signal transduction which inhibited the release of proinflammatory cytokines and finally leaded to immunosuppression.

Relative significances of pH and substrate starch level to roles of Streptococcus bovis S1 in rumen acidosis.

To clarify the relative importance of pH and substrate starch level in fermentation characteristics and regulatory mechanism of Streptococcus bovis S1 in rumen acidosis, an in vitro fermentation of three levels of soluble starch (1, 3 and 9 g/L) was established with pH in the media were maintained constant at 5.5 or 6.5. The results showed that the dominant product of S. bovis S1 was lactate at both pH, the production depended on the starch level, and more lactate was produced at pH 6.5 than that at pH 5.5 (P < 0.001). At pH 5.5, the activity of lactate dehydrogenase (LDH) and α-amylase (α-AMY), their abundances, the relative expressions of LDH, PFL (gene encoding pyruvate formate-lyase), CCPA (gene encoding global catabolite control protein A) and α-AMY genes were higher than those at pH 6.5 (P < 0.05), whereas the concentration of fructose-1,6-diphosphate (FDP) was lower. The activity of LDH, α-AMY and FDP, and the relative expressions of LDH, PFL, CCPA and α-AMY genes were, in general, positively related to the starch level. The canonical regression analysis indicated that the pH had more profound effect compared with the starch level, in terms of the acid productions, enzyme activity and gene expressions. It was concluded that the fermentation of S. bovis was regulated at the transcription level in response to both pH and substrate starch concentration, but more sensitive to pH changes.

Lower ω-6/ω-3 Polyunsaturated Fatty Acid Ratios Decrease Fat Deposition by Inhibiting Fat Synthesis in Gosling.

The objective of the current study was to investigate the effects of dietary ω-6/ω-3 polyunsaturated fatty acid (PUFA) ratios on lipid metabolism in goslings. One hundred and sixty 21-day-old Yangzhou geese of similar weight were randomly divided into 4 groups. They were fed different PUFA-supplemented diets (the 4 diets had ω-6/ω-3 PUFA ratios of 12:1, 9:1, 6:1, or 3:1). The geese were slaughtered and samples of liver and muscle were collected at day 70. The activities and the gene expression of enzymes involved in lipid metabolism were measured. The results show that the activities of acetyl coenzyme A carboxylase (ACC), malic enzyme (ME), and fatty acid synthase (FAS) were lower (p<0.05), but the activities of hepatic lipase (HL) and lipoprotein lipase (LPL) were higher (p<0.05), in the liver and the muscle from the 3:1 and 6:1 groups compared with those in the 9:1 and 12:1 groups. Expression of the genes for FAS (p<0.01), ME (p<0.01) and ACC (p<0.05) were higher in the muscle of groups fed diets with higher ω-6/ω-3 PUFA ratios. Additionally, in situ hybridization tests showed that the expression intensities of the high density lipoprotein (HDL-R) gene in the 12:1 and 9:1 groups were significantly lower (p<0.01) than that of the 3:1 group in the muscle of goslings. In conclusion, diets containing lower ω-6/ω-3 PUFA ratios (3:1 or 6:1) could decrease fat deposition by inhibiting fat synthesis in goslings.

Effects of bamboo vinegar powder on growth performance and mRNA expression levels of interleukin-10, interleukin-22, and interleukin-25 in immune organs of weaned piglets.

The aim of this study was to explore the effects of bamboo vinegar powder on growth performance, diarrhea situation and mRNA expression levels of cytokines i.e., interleukin-10 (IL-10), interleukin-22 (IL-22), and interleukin-25 (IL-25) in immune organs of weaned piglets, and to accumulate theoretical data for the application of bamboo vinegar powder in weaned piglet production. Forty-five crossbred (Duroc × Landrace × Yorkshire, all male) weaned piglets with similar body weight (6.74 ± 0.17 kg) at 31 days of age were randomly assigned to 5 treatments with 3 replicates per treatment and 3 piglets in each replicate. The five treatments were as follows: CON (a basal diet), ANT (the basal diet + 0.12% antibiotics), BV1 (the basal diet + 0.1% bamboo vinegar powder), BV5 (the basal diet + 0.5% bamboo vinegar powder), BV10 (the basal diet + 1.0% bamboo vinegar powder). This experiment lasted 35 days. The growth performance and diarrhea situation were recorded. The relative mRNA expression levels of IL-10, IL-22 and IL-25 in liver, spleen, duodenum and mesenteric lymph nodes were detected by real-time PCR. Feed: gain of BV5 was significantly lower than that of CON (P < 0.05). In comparison with CON, diarrhea rate and diarrhea index of BV1 and BV5 all tended to decrease (P < 0.1). Compared with CON, mRNA expression level of IL-10 in liver of ANT tended to be lower (P < 0.1) and these of BV1, BV5 and BV10 were significantly reduced (P < 0.05). The mRNA expression levels of IL-10 in duodenum of ANT, BV1, BV5 and BV10 were all lower than those of CON, of which BV10 had significantly decreased IL-10 mRNA expression in duodenum (P < 0.05). The mRNA expression levels of IL-22 in duodenum of ANT, BV1, BV5 and BV10 all tended to be inhibited compared with CON (P < 0.1). With the increase of bamboo vinegar powder dosage, mRNA expression levels of IL-25 in spleen and mesenteric lymph nodes of BV1, BV5 and BV10 tended to be up-regulated. Overall, bamboo vinegar powder could improve growth performance, and regulate mRNA expression levels of IL-10, IL-22 and IL-25 in immune organs of weaned piglets. The dosage at 0.5% showed optimum effects.

Effects of supplementation of rumen-protected choline on growth performance, meat quality and gene expression in longissimus dorsi muscle of lambs.

This study determined the effects of rumen-protected choline (RPC) on growth performance, blood lipids, meat quality and expression of genes involved in fatty-acid metabolism in young lambs. A total of 24 Dorper × Hu lambs (about 20 kg body weight) were kept in individual pens and fed diets with 0%, 0.25%, 0.50% and 0.75% RPC for 60 d. Supplementation of 0.25% RPC increased average daily gain of lambs, whereas treatments had no significant effect on feed intake. The pH values of meat were increased at 0.25% RPC and both, dripping loss and shear force of meat, were significantly decreased in RPC-supplemented lambs. No significant changes were observed for dressing percentage and intramuscular fat. RPC supplementations had no significant effect on the concentrations of triglycerides and cholesterols in serum, but the concentration of high-density lipoprotein was decreased at 0.50% RPC and that of low-density lipoprotein was increased at 0.75% RPC. In m. longissimus dorsi, the expressions of cluster of differentiation 36 (CD36), acetyl-CoA carboxylase (ACC) and fatty-acid synthase (FASN) genes were increased at 0.25% RPC. Supplementation of 0.75% RPC increased the expressions of lipoprotein lipase (LPL) and FASN genes, decreased the expression of ACC gene and had no effect on CD36 gene. The results of this study showed that supplementation of 0.25% RPC could promote growth performance of lambs and improve meat quality. This may be mediated by effects on blood lipid profiles and the metabolism of fatty acids in skeleton muscles. However, the beneficial effects of 0.25% RPC supplementation need to be validated with a larger number of animals. Higher doses, particularly 0.75% RPC, showed adverse effects on live weight gain and ACC expression.

Effects of dietary tryptophan on protein metabolism and related gene expression in Yangzhou goslings under different feeding regimens.

This study was conducted to investigate the effects of feeding regimens and dietary Trp levels on protein metabolism and regulation of the related gene expression in Yangzhou goslings. A 2 × 3 factorial completely randomized experiment was applied, and the treatments were designed as 2 feeding regimens (ad libitum vs. restricted feeding), and each contained 3 levels of Trp (low-Trp group, 0.14%; medium-Trp group, 0.22%; high-Trp group, 0.30%). The results show that ADG and feed conversion ratio (FCR) were significantly affected by feeding regimens (P < 0.05); dietary Trp levels influenced ADG and ADFI in the starter and overall period (P < 0.05), and interactions between Trp levels and feeding regimens on ADG, ADFI, and FCR were observed in different growing periods (P < 0.05). Serum total protein, triglycerides, and total cholesterol levels in the ad libitum group were higher than those in the restricted feeding group (P < 0.05), and the concentration of serum total protein, glucose, and insulin-like growth factor-I were higher in the medium-Trp and high-Trp groups (P < 0.05); however, serum uric acid, triglyceride, and cortisol levels were reduced in the high-Trp group (P < 0.05). Feeding regimen and dietary Trp levels affected serum glucose (P < 0.05) interactively. In the ad libitum group, tryptophanyl tRNA synthetase (TTS) mRNA expressed at a higher level in the high-Trp treatment, whereas expression of poultry target of rapamycin (pTOR) and p70 ribosomal protein S6 kinase1 (S6K1) mRNA was upregulated in the low-Trp treatment (P < 0.05). Expression and phosphorylation levels of pTOR were upregulated in thigh tissue with increased dietary Trp, but cathepsin B and 20S protease mRNA expression decreased (P < 0.05). It was concluded that the protein deposition in gosling thigh tissue was affected by dietary Trp through positive regulation of the TTS mRNA and pTOR protein expression and phosphorylation levels for protein synthesis, as well as the suppression of protein degradation-related gene expression.