The impact of lactating Hu sheep's dietary protein levels on lactation performance, progeny growth and rumen development.

This study aimed to investigate whether lactating Hu sheep's dietary protein levels could generate dynamic effects on the performance of their offspring. Twelve ewes with similar parity were fed iso-energy diets which contained different protein levels (P1: 9.82%, P2: 10.99%) (n = 6), and the corresponding offspring were divided into SP1 and SP2 (n = 12). At 60 days, half of the lambs were harvested for further study: the carcass weight (p = 0.043) and dressing percentage (p = 0.004) in the SP2 group were significantly higher than SP1. The acetic acid (p = 0.007), propionic acid (p = 0.003), butyric acid (p < 0.001) and volatile fatty acids (p < 0.001) in rumen fluid of SP2 were significantly lower than SP1. The expression of MCT2 (p = 0.024), ACSS1 (p = 0.039) and NHE3 (p = 0.006) in the rumen of SP2 was lower than SP1, while the HMGCS1 (p = 0.026), HMGCR (p = 0.024) and Na+/K+-ATPase (p = 0.020) was higher than SP1. The three dominant phyla in the rumen are Bacteroidetes, Proteobacteria and Firmicutes. The membrane transport, amino acid metabolism and carbohydrate metabolism of SP1 were relatively enhanced, the replication and repair function of SP2 was relatively enhanced. To sum up, the increase of dietary protein level significantly increased the carcass weight and dressing percentage of offspring and had significant effects on rumen volatile fatty acids, acetic acid activation and cholesterol synthesis related genes. HIGHLIGHTSIn the early feeding period, the difference in ADG of lambs was mainly caused by the sucking effect.The increase in dietary protein level of ewes significantly increased the carcass weight and dressing percentage of offspring.The dietary protein level of ewes significantly affected the volatile fatty acids (VFAs) and genes related to acetic acid activation and cholesterol synthesis in the rumen of their offspring.The membrane transport, amino acid metabolism and carbohydrate metabolism of the offspring of ewes fed with a low protein diet were relatively enhanced.The replication and repair function of the offspring of ewes fed with a high protein diet was relatively strengthened.

Dietary niacin affects intestinal morphology and functions via modulating cell proliferation in weaned piglets.

Niacin deficiency leads to inflammation of mucous membranes and diarrhoea. There are few reports on the effects of niacin on the intestinal health of weaned piglets. The present study was conducted to analyse the effects of niacin in weaned piglets along with its underlying mechanism. A total of 48 25-day-old weaned piglets (24 females and 24 males) were randomly allotted into four groups, each treatment were supplemented with 22.5, 30, 45, and 75 mg kg-1 niacin for a period of 14 days, with 12 piglets per diet and 1 piglet per pen. Six piglets (3 males and 3 females) were randomly selected from each treatment group and euthanised for intestinal tissue sampling on days 7 and 14 after the weaning day (day 0), respectively. Dietary niacin did not affect the growth performance of weaned piglets but quadratically affected (P < 0.05) the diarrhoea rate from days 7 to 14. The duodenal villus height and width and crypt depth in the 30 mg kg-1 niacin group were greater than those in the 45 mg kg-1 niacin group on day 7, and the jejunal crypt depth, ileal crypt depth, villus height and villus width decreased (linear, P < 0.05) with the increase in dietary niacin. However, the dietary supplementation with niacin increased (linear, P < 0.001) the jejunal villus height, crypt depth and villus width on day 14. Dietary niacin increased (linear, P < 0.05) the alkaline phosphatase activity in the jejunal mucosa of weaned piglets on day 7 but decreased (linear, P < 0.05) its activity on day 14. The number of Ki67 positive cells per crypt was decreased (linear, P < 0.05) with the dietary niacin on day 7 but increased (linear, P < 0.05) with dietary niacin contents on day 14. Moreover, dietary niacin altered (P < 0.05) SLC5A1, SLC15A1, SLC6A19, TJP-1, occludin and claudin-1 mRNA expression in the small intestine. These results indicate that dietary niacin has different effects on intestinal morphology and functions in the first and second weeks postweaning and that the dietary supplementation with niacin may, by modulating intestinal cell proliferation, affect the intestinal health.

Effects and interaction of dietary electrolyte balance and citric acid on growth performance, intestinal histomorphology, digestive enzyme activity and nutrient transporters expression of weaned piglets.

Fifty-six piglets were weaned at 21 days and randomly assigned to 1 of 8 dietary treatments with 7 replicate pens for a 14-day experimental period. The eight experimental diets were prepared via a 2 × 4 factorial arrangement with citric acid (CA; 0 and 0.3%) and dietary electrolyte balance (dEB, Na +K - Cl mEq/kg of the diet; -50, 100, 250, and 400 mEq/kg). Varying dEB values were obtained by altering calcium chloride and sodium bicarbonate contents. Dietary CA significantly increased (p < .05) villus height (VH) and villus height:crypt depth (VH:CD) in the jejunum. Piglets fed a 250 mEq/kg diet increased (p < .05) VH and VH:CD values in the duodenum. Jejunal VH and VH:CD increased (quadratic; p < .05), and ileal VH:CD (liner and quadratic; p < .05) decreased as dEB was increased in diets without CA, but no such effect was observed on the diets containing CA (dEB ×CA; p < .05). The CD in jejunum (quadratic; p < .05) increased as dEB was increased in diets containing CA, whereas it was decreased (linear; p < .05) in the diets without CA (dEB ×CA; p < .001). Dietary CA increased maltase activity and reduced the number of Ki67-positive cells (p < .05). Increasing dEB values in diets without CA increased sucrose and lactase activities (quadratic; p < .05), but no such effect was observed in the diets with CA (dEB ×CA; p < .05). An interaction effect between dEB and CA on the number of Ki67-positive cells was observed (p < .001). In conclusion, 250 mEq/kg dEB diet with CA improved piglet intestinal digestion and absorption function by improving intestinal morphology and increasing digestive enzyme activities. However, these improvements were also observed in piglets fed the 100 mEq/kg dEB diet without CA.

Effects of iron on intestinal development and epithelial maturation of suckling piglets.

The purpose of the present study was to discover the effects of iron on the intestinal development and epithelial maturation of suckling piglets. Twenty-seven newborn male piglets from 9 sows (3 piglets per sow), with similar body weight, were selected. The 3 piglets from the same sow were randomly divided into 1 of the 3 groups. The piglets were orally administrated with 2 mL of normal saline (CON group) or with 25 mg of iron by ferrous sulfate (OAFe group; dissolved in normal saline) on the 2nd, 7th, 12th, and 17th day, respectively, or intramuscularly injected with 100 mg of iron by iron dextran (IMFe group) on the 2nd day. The slaughter was performed on the 21st day and intestinal samples were collected. Compared with the CON group, iron supplementation significantly increased the length (P < 0.001), weight (P < 0.001), relative weight (P < 0.001), and the length:weight ratio (P < 0.001) of the small intestine in both OAFe and IMFe groups. The villus height (P < 0.001), crypt depth (CD) (P < 0.001), villus width (P = 0.002), and surface area (P < 0.001) in the jejunum of IMFe and OAFe piglets were also greater than those in CON piglets. The mRNA expression of trehalase (Treh; P = 0.002) and sucrase isomaltase (Sis; P = 0.043), markers of epithelial maturation, increased in OAFe and IMFe piglets, respectively. Moreover, enterocyte vacuolization, observed in fetal-type enterocyte, was reduced in OAFe and IMFe piglets, compared with CON piglets. However, no significant difference in the expression of the target genes of wnt/ß-catenin signaling pathway was observed. The results indicated that both oral administration and intramuscular injection with iron promoted intestinal development and epithelial maturation in suckling piglets and that the effects of iron may be independent of wnt/ß-catenin signaling.

Effects and interaction of dietary electrolyte balance and citric acid on the intestinal function of weaned piglets.

Fifty-six piglets (6.26 ± 0.64 kg BW) were weaned at 21 d and randomly assigned to one of the eight dietary treatments with seven replicate pens for a 14-d experimental period. The eight experimental diets were prepared via a 2 × 4 factorial arrangement with citric acid (CA; 0% and 0.3%) and dietary electrolyte balance (dEB, Na + K - Cl mEq/kg of the diet; -50, 100, 250, and 400 mEq/kg). Varying dEB values were obtained by altering the contents of calcium chloride and sodium bicarbonate. An interaction (P < 0.05) between dEB and CA in diarrhea score and the number of goblet cell in jejunum were observed. Ileum pH significantly decreased in weaned piglets fed 250 mEq/kg dEB diet compared with those fed -50 and 400 mEq/kg dEB diets (P < 0.05). Supplementation of 0.3% CA decreased the number of goblet cell in the ileal crypt (P < 0.05) and the relative mRNA expression of cystic fibrosis transmembrane conductance regulator, tumor necrosis factor-α, interferon-γ (IFN-γ), interleukin-1ß (IL-1ß), interleukin-10 (IL-10), zona occludens-1, and Claudin-1 (P < 0.05). Increasing dEB values increased the number of goblet cells in the jejunal crypt (P < 0.05). A 250-mEq/kg dEB diet decreased the relative mRNA expression of IFN-γ, IL-1ß, and IL-10 (P < 0.05) than 100-mEq/kg dEB diet. The interaction between dEB and CA on the relative abundances of Cyanobacteria and Saccharibacteria was observed (P < 0.05). Supplementation of 0.3% CA increased relative abundances of and Streptococcus hyointestinalis. Piglets fed 250-mEq/kg diet increased relative abundances of Firmicutes and Lactobacillus rennini, and decreased the relative abundance of Proteobacteria, Veillonella, Actinobacillus minor, and Escherichia-Shigella.In conclusion, supplementation of 0.3% CA resulted in differential expression of inflammatory cytokines, ion transporters, and tight junction proteins, and changes in the microbial community composition. A 250-mEq/kg dEB diet reduced gastrointestinal pH and promoted the enrichment of beneficial microbes in the gut microbiota, thereby suppressing inflammation and harmful bacteria. However, the addition of CA to diets with different dEB values did not promote intestinal function in weaned piglets.

Effects of oral monosodium glutamate administration on serum metabolomics of suckling piglets.

This study was conducted to determine the effects of oral administration with glutamate on metabolism of suckling piglets based on 1 H-Nuclear magnetic resonance (1 H NMR) spectroscopy through the level of metabolism. Forty-eight healthy [(Yorkshire × Landrace) × Duroc] piglets born on the same day with a similar birth bodyweight (1.55 ± 0.20 kg) were obtained from six sows (8 piglets per sow). The piglets from each sow were randomly assigned into four treatments (2 piglets per treatment). The piglets were given 0.09 g/kg body weight (BW) of sodium chloride (CN group), 0.03 g/kg BW monosodium glutamate (LMG group), 0.25 g/kg BW monosodium glutamate (MMG group) and 0.50 g/kg BW monosodium glutamate (HMG group) twice a day respectively. An 1 H NMR-based metabolomics' study found that the addition of monosodium glutamate (MSG) significantly reduced serum citrate content in 7-day-old piglets, while HMG significantly increased serum trimethylamine content and significantly reduced unsaturated fat content in 7-day-old piglets (p < .05). The content of glutamine, trimethylamine, albumin, choline and urea nitrogen was significantly increased and the creatinine content decreased significantly in the 21-day-old HMG (p < .05). Analysis of serum hormones revealed that glucagon-like peptide-1 (GLP-1) content in the 21-day-old HMG was highest (p < .05). The cholecystokinin (CCK) content in the HMG of 7-day-old piglets was lower than that in the LMG (p < .05), and the CCK content in the serum of the 21-day-old MMG was highest (p < .05). The serum leptin levels in the 21-day-old HMG were the lowest (p < .05). The serum insulin content in the 7-day-old MMG was highest (p < .05). This study suggests that MSG plays an important role in the metabolism of sugar, fat and protein (amino acids). These results provide a theoretical basis for designing piglet feed formulations.

The effects of dietary supplementation with hyodeoxycholic acid on the differentiation and function of enteroendocrine cells and the serum biochemical indices in weaned piglets1.

Bile acid, a cholesterol metabolite, promotes gastrointestinal tract digestion and absorption of cholesterol, lipids, and fat-soluble vitamins. It is a signaling regulatory molecule that influences a variety of endocrinal and metabolic activities. This study investigated the effects of hyodeoxycholic acid (HDCA) as a dietary supplement on endocrine cell differentiation and function and weaned piglet serum biochemical indices. Sixteen piglets [Duroc × (Landrace × Yorkshire)] were individually housed and weaned at 21 d of age (BW of 6.14 ± 0.22 kg). Uniform weight animals were randomly assigned to 1 of 2 treatments (8 replicate pens per treatment and 1 piglet per pen). The treatments were 1) base diet (control) and 2) base diet supplemented with 2 g/kg of HDCA. Control and HDCA piglet numbers of chromogranin A (CgA)-positive cells per crypt did not differ. HDCA CgA-positive cells numbers decreased (P < 0.05) in the jejunal villi showed a tendency to decrease (P < 0.10) in the ileal villi and showed tendency toward an increase (P < 0.10) in the duodenal villi compared with the controls. The HDCA diet led to a decline in glucagon-like peptide 2 (P < 0.01) concentrations, but did not affect plasma glucagon-like peptide 1. HDCA supplementation increased (P < 0.05) the mRNA expression of jejunal Insm1, Sst, PG, and Gast, but decreased (P < 0.05) duodenal expression of Insm1, jejunal Pdx1, and ileal NeuroD1. HDCA elevated globulin and immunoglobulin A (P < 0.05) serum concentrations and decreased the albumin/globulin ratio (P < 0.05). Total protein and immunoglobulin G serum levels tended to increase compared with the control group. These results indicate that dietary HDCA at 2 g/kg may regulate enteroendocrine cell differentiation and play a role in increasing weaned piglet humoral immunity.

The effects of dietary supplementation with hyodeoxycholic acid on the differentiation and function of enteroendocrine cells and the serum biochemical indices in weaned piglets.

Bile acid, a cholesterol metabolite, promotes gastrointestinal tract digestion and absorption of cholesterol, lipids, and fat-soluble vitamins. It is a signaling regulatory molecule that influences a variety of endocrinal and metabolic activities. This study investigated the effects hyodeoxycholic acid (HDCA) as a dietary supplement on endocrine cell differentiation and function and weaned piglet serum biochemical indices. Sixteen piglets (Duroc × [Landrace × Yorkshire]) were individually housed and weaned at 21 days of age (body weight of 6.14 ± 0.22 kg). Uniform weight animals were randomly assigned to one of two treatments (eight replicate pens per treatment and one piglet per pen). The treatments were 1) base diet (control); and 2) base diet supplemented with 2 g/kg of HDCA. Control and HDCA piglet numbers of CgA-positive cells per crypt did not differ. HDCA CgA-positive cells numbers decreased (P < 0.05) in the jejunal villi, showed a tendency to decrease (P < 0.10) in the ileal villi, and showed tendency toward an increase (P < 0.10) in the duodenal villi compared to the controls. The HDCA diet led to a decline in GLP-2 (P < 0.01) concentrations, but did not affect plasma GLP-1. HDCA supplementation increased (P < 0.05) the mRNA expression of jejunal Insm1, Sst, PG, and Gast, but decreased (P < 0.05) duodenal expression of Insm1, jejunal Pdx1, and ileal NeuroD1. HDCA elevated GLO and IgA (P < 0.05) serum concentrations and decreased the A/G ratio (P < 0.05). TP and IgG serum levels tended to increase compared to the control group. These results indicate that dietary HDCA at 2 g/kg may regulate enteroendocrine cell differentiation and play a role in increasing weaned piglet humoral immunity.

Effects of dietary supplementation with epidermal growth factor on nutrient digestibility, intestinal development and expression of nutrient transporters in early-weaned piglets.

The abnormalities in intestinal morphology and digestive function during weaning are associated with the loss of milk-borne growth factors. Epidermal growth factor (EGF) has been shown to stimulate the growth of animals. This study was to determine the effect of dietary EGF on nutrient digestibility, intestinal development and the expression of genes encoding nutrient transporters in weaned piglets. Forty-two piglets were weaned at 21 days and assigned to one of three treatment groups: (1) basal diet (control), (2) basal diet + 200 µg/kg EGF or (3) basal diet + 400 µg/kg EGF. Each treatment consisted of 14 replicates, and seven piglets from each treatment were sampled on day 7 and 14. The EGF supplementation significantly elevated (p < 0.05) the coefficients of total tract apparent digestibility of crude protein, calcium and phosphorus, but tended to decrease sucrase activity (p < 0.10) than the control group. At day 7 post-weaning, animals receiving EGF diets showed a tendency (p < 0.10) towards greater ileal villus height (VH), jejunal crypt depth (CD) and duodenal VH:CD when compared with the control group. Moreover, the mRNA levels of glucose transporter 2 (Slc2a2), neutral amino acid transporter (Slc6a19) and calbindin D9k (S100G) tended to be higher (p < 0.10) for EGF groups than the control group. By day 14, EGF supplementation markedly enhanced (p < 0.05) the VH, CD and VH:CD in the jejunum compared to the control group. This addition also up-regulated (p < 0.05) the mRNA level and the protein abundance of peptide transporter 1 than the control group. These findings demonstrated that dietary EGF beneficially enhanced nutrient digestibility, improved intestinal development and increased the mRNA expression of nutrient transporters in weaned piglets.

Dietary vitamin E affects small intestinal histomorphology, digestive enzyme activity, and the expression of nutrient transporters by inhibiting proliferation of intestinal epithelial cells within jejunum in weaned piglets1.

Vitamin E (VE) is an indispensable vitamin in piglet feed formula. Among other things, it affects tissues including small intestine tissues and in particular its major unit intestinal epithelial cells. Previously, limited in vivo experiments have focused on the effect of VE on the intestine, particularly digestion and absorption. VE has been shown to inhibit proliferation of some types of cells. This experiment was conducted to test the hypothesis that VE affects intestinal functions by influencing the intestinal epithelial cell proliferation. Thirty 21-d old weaned [(Yorkshire × Landrace) × Duroc] piglets with BWs of 6.36 ± 0.55 kg were randomly divided into five VE-containing feeding formula groups. The treatments were (i) 0 IU (control), (ii) 16 IU, (iii) 32 IU, (iv) 4. 80 IU, and (v) 5. 160 IU. The treatments lasted 14 d. At the end of the experiment, all subjects were sacrificed to obtain blood and tissue samples. The results suggest that VE did not affect the growth performance. VE did tend to decrease jejunal crypt depth (linear, P = 0.056) and villus width (linear, P < 0.05). Sucrase activity significantly decreased in the adding 80 IU VE compared with the control (P < 0.05). Jejunal crypt, cell proliferation in 80 IU group significantly decreased compared with the control group (P < 0.05). This study suggests that dietary VE may affect intestinal morphology and functions by inhibiting weaned piglet jejunal epithelial cell proliferation.

Dietary sulfur amino acids affect jejunal cell proliferation and functions by affecting antioxidant capacity, Wnt/ß-catenin, and the mechanistic target of rapamycin signaling pathways in weaning piglets.

Intestinal epithelial cells undergo rapid renewal along the crypt-villus axis (CVA), which ensures intestinal functions. Weaning stress differentially effects intestinal epithelial cell metabolism and physiological states along the CVA. Sulfur amino acids (SAA) play a key role in intestinal epithelial cell functioning. This study evaluated the effects of SAA dietary supplementation on weaning pig jejunal epithelial cells along the CVA. Sixteen Duroc × Landrace × Yorkshire piglets (6.16 ± 0.22 kg BW) were weaned at 21 d of age and were blocked by BW and gender and the randomly assigned to 1 of 2 groups fed diets consisting of low (0.53%) or high (0.85%) levels of SAA for a 7-d period. All piglets were euthanized for tissue sampling on day 7 postweaning. Jejunal epithelial cells were isolated along the CVA to yield 3 "cell fractions" (upper villus, middle villus, and crypt cells). The number of proliferating cells per crypt of piglets fed the high SAA diet was lower (P < 0.05) than that for low SAA diet. High SAA diet piglets tended to have decreased (P = 0.059) sucrase activities compared low SAA diet piglets. A high SAA diet increased (P < 0.05) total antioxidant capacity, catalase, and superoxide dismutase activities compared with a low SAA diet. mRNA expression levels of claudin-1, Slc5a1, and Slc7a9 in high SAA diet piglets were lower (P < 0.05) than for low SAA diet piglets. There were no interactions between dietary SAA and cell sections along the CVA for enzyme activities and mRNA expression in any of the weaned piglets. Protein amounts and phosphorylation levels related to Wnt/ß-catenin and mechanistic targeting of rapamycin (mTOR) signaling pathways were affected by SAA in weaning piglets. These findings indicate that dietary SAA affects jejunal cell proliferation and functions in weaning piglets. There appears to be no interactions between dietary SAA and cell sections along the CVA. The effects of SAA may be partly through affecting antioxidant capacity, and Wnt/ß-catenin and mTOR signaling pathway.

Design of guanidinium ionic liquid based microwave-assisted extraction for the efficient extraction of Praeruptorin A from Radix peucedani.

A series of novel tetramethylguanidinium ionic liquids and hexaalkylguanidinium ionic liquids have been synthesized based on 1,1,3,3-tetramethylguanidine. The structures of the ionic liquids were confirmed by (1)H NMR spectroscopy and mass spectrometry. A green guanidinium ionic liquid based microwave-assisted extraction method has been developed with these guanidinium ionic liquids for the effective extraction of Praeruptorin A from Radix peucedani. After extraction, reversed-phase high-performance liquid chromatography with UV detection was employed for the analysis of Praeruptorin A. Several significant operating parameters were systematically optimized by single-factor and L9 (3(4)) orthogonal array experiments. The amount of Praeruptorin A extracted by [1,1,3,3-tetramethylguanidine]CH2CH(OH)COOH is the highest, reaching 11.05 ± 0.13 mg/g. Guanidinium ionic liquid based microwave-assisted extraction presents unique advantages in Praeruptorin A extraction compared with guanidinium ionic liquid based maceration extraction, guanidinium ionic liquid based heat reflux extraction and guanidinium ionic liquid based ultrasound-assisted extraction. The precision, stability, and repeatability of the process were investigated. The mechanisms of guanidinium ionic liquid based microwave-assisted extraction were researched by scanning electron microscopy and IR spectroscopy. All the results show that guanidinium ionic liquid based microwave-assisted extraction has a huge potential in the extraction of bioactive compounds from complex samples.

Copper is required for cobalt-induced transcriptional activity of hypoxia-inducible factor-1.

Cobalt inhibits prolyl hydroxylases, leading to the accumulation of hypoxia-inducible factor-1α (HIF-1α) and a concomitant increase in the transcriptional activity of HIF-1. Therefore, cobalt has been under development as a drug for activating HIF-1 under some disease conditions. However, it has been shown that ischemic conditions resulted in the loss of copper, and the activation of HIF-1 would not occur unless copper was supplemented. The present study was undertaken to test the hypothesis that copper is also required for the cobalt activation of HIF-1 transcriptional activity. Human umbilical vein endothelial cells subjected to treatment with cobalt chloride (CoCl(2)) at concentrations above 25 µM for 2 h resulted in an accumulation of HIF-1α, which was determined by Western blot analysis, and an increase in the expression of vascular endothelial growth factor (VEGF), which was determined by real-time reverse transcription-polymerase chain reaction analysis for mRNA levels and enzyme-linked immunosorbent assay analysis for protein levels. The copper chelator tetraethylenepentamine at 25 µM did not significantly affect the accumulation of HIF-1α but blocked increases in VEGF mRNA and protein levels, an effect that could be reversed by the addition of 25 µM copper sulfate (CuSO(4)). In addition, gene silencing of the copper chaperone for Cu,Zn-superoxide dismutase blocked VEGF expression with little effect on cobalt-induced HIF-1α accumulation. The present study thus demonstrates that copper was required for cobalt-activated transcriptional activity of HIF-1, although copper did not affect cobalt-induced accumulation of HIF-1α in the cells.