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This study was conducted to determine the effects of soy isoflavones on changes in body and tissue weight and on insulin-like factor I (IGF-I) and peroxisome proliferator-activated receptor-γ (PPARγ) gene and protein expression in muscle and adipose tissues in Chinese Guangxi minipig, as a model for studying human nutrition. A total of 72 male Chinese Guangxi minipigs were fed basal diet (control, Con), low dose of soy isoflavones and high dose of soy isoflavones (HSI). The results showed that HSI increased the body weight (BW) gain and fat percentage of minipigs (P < 0.05). In addition, the serum concentrations of IGF-I and interleukin-6 were increased by high levels of soy isoflavones (P < 0.05). Furthermore, a diet containing soy isoflavones enhanced IGF-I mRNA expression levels in longissimus muscle, but decreased these levels in perirenal fat. However, the mRNA and protein expression levels of PPARγ in longissimus muscle and subcutaneous adipose tissue were both increased when compared with the Con. The data indicated that soy isoflavones regulated the BW gain and fat percentage of Chinese Guangxi minipigs, which also showed changes in IGF-I system and PPARγ. However, further research is required to clarify the causative relationship. [ABSTRACT FROM AUTHOR]

L-type amino acid transporter-1 (LAT1) transports large, branched-chain, aromatic and neutral amino acids. About 64 Duroc x Landrace x Yorkshire pigs were used to study the effects of dietary crude protein (CP), energy and arginine on LAT1 expression in forebrain. The results showed that LAT1 expression in forebrain was sensitive to different levels of CP, energy and arginine. On the basis of Western blot analysis, a lower level of LAT1 presented in the brain tissues of pigs fed the low dietary CP diet (P <0.05), a higher level were found in pigs fed the higher CP diet, with moderate to intense staining seen in pigs fed the diet plus 1% arginine. In contrast, pigs fed the control-energy diet had weak LAT1 expression, and those fed the diet supplemented with 1% arginine showed lowest LAT1 expression (P <0.05). These results showed that LAT1 was highly expressed in the forebrain, and expression of LAT1 was affected by dietary protein, energy and arginine differently. [ABSTRACT FROM AUTHOR]

Cottonseed meal (CM) and rapeseed meal (RM) have been used as alternative protein sources in porcine feed, but their exact digestive regulation remains unclear. This study was conducted to determine the dynamic profiles of AA released from different nitrogen composited diets in the jejunum of pigs. Seventy-two pigs (19.3 kg BW) were randomly assigned into 4 groups (18 pigs per group) and fed diets containing corn and either fish meal (FM), soybean meal (SBM), CM, or RM with equivalent AA for 7 d. The digesta of the jejunum were collected at 1, 4, and 8 h after feeding. The hydrolysate AA of undigested protein (HAA), free AA (FAA), and peptide-bound AA (PAA) in the digesta were determined. The lowest HAA contents were observed in the FM and SBM groups at 4 h. High levels of FAA were released from the SBM diet, whereas low levels of FAA were released from the RM diet at 1 and 4 h after feeding. The concentration of PAA in the CM group was lower than those in the FM and SBM groups. These results showed that the SBM diet could be easily degraded to FAA and peptide, and the FM diet tended to be degraded to peptide in the jejunum. There were less FAA and PAA released from the CM and RM diets although dietary AA were balanced, but the RM diet released more FAA and PAA than the CM diet. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the profiles of AA in different segments of the gastrointestinal tract of pigs fed with different nitrogen composited diets. Twenty-four pigs (19.5 kg BW) were randomly assigned into 4 groups (6 pigs per group) and fed diets containing corn and fish meal (FM), soybean meal (SBM), cottonseed meal (CM), or rapeseed meal (RM) with equivalent AA compositions for 7 d. The contents of the stomach, proximal jejunum, distal jejunum, and ileum were collected at 4 h after feeding. The hydrolysate AA of undigested protein, free AA (FAA), and peptide-bound AA (PAA) in the contents were determined. There were more FAA in the proximal jejunum of SBM protein diets treatment, whereas more peptides were obtained from FM protein diets in the stomach and ileum as well as from SBM protein diets in the distal jejunum. The concentrations of FAA in the proximal jejunum and ileum as well as PAA in the jejunum with RM were higher than those with CM. When all 4 treatments were considered together, whereas few FAA were in the stomach and then increased in the jejunum and ileum, PAA were distributed uniformly in the 4 segments. These results showed that the RM protein diet gave a relatively continuous release of hydrolysis products in the stomach and small intestine. And FM and SBM protein diets were superior to CM for the release of peptides and FAA in the proximal gastrointestinal tract. These results regarding the AA profiles in different segments of the gastrointestinal tract should help to provide some information for the application of CM and RM in pigs. [ABSTRACT FROM AUTHOR]

This experiment investigated the effects of feeding graded levels of a soya-bean protein product (HP300, Hamlet Protein A/S Company, Denmark) on endogenous ileal lysine loss, apparent ileal amino acid digestibility, standardized true ileal amino acid digestibility determined using the protein-free (PF) method, and real ileal amino acid digestibility determined using the homoarginine (HA) method. The soya-bean protein product was obtained by purifying and defattening soya bean via a proprietary microbial process that decreased the level of trypsin inhibitors and other anti-nutritional factors in soya bean. Six barrows, with an initial body weight of 37.4 ± 1.3 kg, were surgically fitted with simple T-cannulae at the distal ileum and offered six maize-starch-based diets according to a 6 x 6 Latin-square design. The six diets were formulated to provide 0, 50, 100, 150, 200, or 250 g crude protein (CP) per kg by dietary inclusion of 0, 90, 182, 274, 367 or 460 g/kg of soya-bean protein. Five kg of soya-bean protein product was guanidinated in order to estimate endogenous amino acid flow and real ileal amino acid digestibility. Chromium III oxide (5 g/kg) was included in the non-guanidinated diets while dysprosium chloride (0.1 g/kg) was included in the guanidinated diets as an indigestible marker. The experimental periods lasted 8 days. On day 6 of each period, ileal digesta was collected for 24 h to determine apparent and standardized true ileal amino acid digestibility of the non-guanidinated diets. At 08:00 h on day 8, the pigs were given a single meal of the diets containing guanidinated protein and their ileal digesta was collected for 24 h in order to determine the total HA flow and the real ileal digestibility of lysine. Endogenous ileal lysine flow appeared to follow a sigmoid curve starting at about 370 mg/kg dry matter (DM) intake for pigs given the PF diet and continuing asymptotically to about 750 mg/kg DM intake when the inclusion level of the soya-bean protein product was increased to 182 g/kg (100 g/kg of CP). The endogenous ileal lysine flow for pigs given the PF diet was similar (P>0.05) to that of pigs given 90 g/kg soya-bean protein (50 g/kg of CP) and it increased sharply (P<0.05) as the level of soya-bean protein increased from 90 to 182 g/kg (50 to 100 g/kg of CP). Thereafter, it was relatively constant (P>0.05). With an increase in soya-bean protein, there was a quadratic increase (P<0.01) in the apparent ileal digestibilities for all amino acids except valine and phenylalanine. Standardized true ileal amino acid digestibility decreased (P<0.05) with an increase in soya-bean protein level. However, real ileal amino acid digestibilities were not influenced (P>0.05) by soya-bean protein in the diet at levels between 90 and 367 g/kg (50 and 200 g/kg of CP). In conclusion, endogenous ileal lysine flow was not constant and was significantly affected by soya-bean protein level. The results of this study suggest that standardized true ileal amino acid digestibility should be measured between 100 and 200 g/kg of CP (182 and 367 g/kg soya-bean protein) while real ileal amino acid digestibility is unaffected by protein levels between 50 and 200 g/kg of CP (90 and 367 g/kg soya-bean protein). [ABSTRACT FROM AUTHOR]

The effect of dietary chitosan oligosaccharides (COS) supplementation on ileal digestibilities of nutrients and performance in broilers was assessed by feeding graded levels (0, 50, 100, 150 mg/kg) of COS. Two thousand four hundred male commercial Avian broilers (1-d-old) were assigned randomly to 5 dietary treatment groups (60 birds per pen with 8 pens per treatment). Diet A was a typical corn- and soybean meal-based diet supplemented with 6 mg/kg of an antibiotic flavomycin (positive control). Diet B was the basal diet without any supplement. Diets C, D, and E were formulated by adding 50, 100, and 1.50 mg/kg of COS to the basal diet, respectively. On the morning of d 21 and 42, 64 birds (8 per pen with 8 pens per treatment) from the growth trial for each age group were killed by cervical dislocation for determination of the ileal digestibilities of nutrients. Dietary supplementation with COS and antibiotic enhanced (P < 0.05) the ileal digestibilities of DM, Ca, P, CP, and all amino acids (except for alanine in the 21-d-old birds or phenylalanine, glutamate, and glycine for the 42-d-old birds). Feed efficiency was improved (P < 0.05) in response to dietary supplementation of an antibiotic or COS (150 mg/kg for d 1 to 21, and 100 and 150 mg/kg for d 21 to 42). The results demonstrate for the first time to our knowledge that dietary COS supplementation was effective in increasing the ileal digestibilities of nutrients and feed efficiency in broilers. Our findings may explain a beneficial effect of COS on chicken growth performance. [ABSTRACT FROM AUTHOR]

In order to deeply investigate the dielectric and ferroelectric photovoltaic properties of BiFeO3 (BFO) thin films, the Pt/BFO/La 0. 5 Sr 0. 5 CoO3 (LSCO) heterostructure ferroelectric capacitor grown on (001) SrTiO3 (STO) substrate is successfully fabricated by off-axis magnetron sputtering. The X-ray diffraction (XRD) and Phi scanning results show that the STO-based BFO and LSCO films are both (001) epitaxial structure. Although the BFO ferroelectric film exhibits an obvious dielectric dispersion phenomenon, a remarkable ferroelectric photovoltaic performance is obtained with open circuit voltage ( V OC ) of 0.38 V and short-circuit current ( J SC ) of 0.23 mA/cm2, respectively. With increasing test temperatures, V OC decreases slowly and then rapidly, while J SC increases rapidly and then decreases. At a critical temperature of 80∘C, the BFO ferroelectric film exhibits a faster photovoltaic response, in which the values of V OC and J SC are about 0.19 V and 0.28 mA/cm2, respectively. Moreover, the energy band analysis indicates that a large work function difference (∼ 1 eV) between LSCO and Pt leads to a strong built-in electric field in the BFO film, which is beneficial to separate the photo-generated carriers and improve ferroelectric photovoltaic effect. In all, this study not only shows that BFO is an excellent and environmentally friendly photovoltaic candidate material, but also provides a practical strategy for improving the performance of BFO ferroelectric photovoltaic devices. [ABSTRACT FROM AUTHOR]

Recent in vivo work with growing pigs suggests that the small intestinal mucosa plays an important role in degrading dietary essential amino acids (EAA). This study was conducted to test the hypothesis that EAA are extensively catabolized by pig enterocytes. Jejunal enterocytes were isolated from ten 50-d-old pigs weaned at 21 d of age (5 barrows and 5 gilts). Cells were incubated at 37 oC for 45 min in 2-ml oxygenated (95% O2/5% CO2) Krebs-bicarbonate buffer (pH 7.4) containing 1% BSA, 5 mM glucose, and plasma concentrations of amino acids (Wu et al. J Nutr 127: 2342, 1997). The medium also contained one of the following L-amino acids at 0.5, 2, or 5 mM plus their L-[1-14C]- or L-[U-14C]-labeled tracers: His, Ile, Leu, Met, Phe, Lys, Thr, Trp, and Val, as well as 0 or 5 mM L-cycloserine (an inhibitor of transaminase). The use of [1-14C]- and [U-14C]-labeled amino acids allowed for quantification of the oxidation of their carboxyl carbons and remaining carbon skeletons (Wu et al. Int J Biochem 19: 937, 1987). Results indicate extensive transamination of all the three branched-chain amino acids (BCAA) in enterocytes, with their α-ketoacids undergoing limited oxidation by branched-chain α-ketoacid dehydrogenase or the Krebs cycle. BCAA degradation was markedly inhibited by L-cycloserine (P < 0.01). Rates of enterocyte BCAA catabolism did not differ (P > 0.05) between barrows and gilts. Oxidation of all other EAA was negligible in the cells from barrows or gilts. The lack of degradation of His, Met, Phe, Lys, Thr, and Trp was confirmed by HPLC analysis of amino acids in medium plus incubated cells. Collectively, our results demonstrate that BCAA are degraded substantially in pig enterocytes and that these cells are not the site for the extensive catabolism of His, Lys, Met, Phe, Thr, and Trp in the pig small intestine. Supported by funds from the Chinese Academy of Sciences, China NSF, and TAES. [ABSTRACT FROM AUTHOR]

There are marked decreases in both plasma cortisol concentrations and intestinal activity of N-acetylglutamate synthase (NAGS; a key enzyme in arginine synthesis) in piglets during the suckling period. This study was designed to test the hypothesis that cortisol may play an important role in regulating intestinal NAGS expression in sowreared piglets. Thirty-two 7-day-old suckling pigs were randomly assigned to one of four groups with seven animals each, and received intramuscular injections of vehicle solution (sesame oil) (control group), hydrocortisone-21-acetate (HYD) (25 mg/kg body wt), RU486 (10 mg/kg body wt) (a potent blocker of glucocorticoid receptors), or HYD plus RU486. During the entire experimental period, pigs were nursed by sows. At 14 days of age, pigs were sacrificed for preparation of jejunal enterocytes for measurements of synthesis of citrulline and arginine from glutamine and proline, mitochondrial activity of NAGS, and mitochondrial concentration of N-acetylglutamate (NAG), using established methodologies (Wu, Am J Physiol 272: G1382, 1997; Bush et al. J Nutr 132: 59, 2002). Cortsiol administration had no effect (P > 0.05) on body weight but increased (P < 0.05) jejunal weight and villus height, compared with the control group. The cortisol treatment enhanced 1) NAGS activity and prevented the postnatal decline in NAGS activity during the suckling period; 2) increased NAG concentration as well as citrulline and arginine synthesis from glutamine and proline in enterocytes (P < 0.01), in comparison with the control group. The stimulatory effects of cortisol on intestinal NAGS activity and arginine synthesis were abolished (P < 0.01) by co-administration of RU486. Our results indicate that cortisol treatment provides a novel and effective means to prevent the marked declines in intestinal NAGS expression and arginine synthesis in suckling piglets via a glucocorticoid receptor-mediated mechanism. Supported by funds from the Chinese Academy of Sciences, China NSF, and USDA. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the effect of dietary starch sources on the balance of glucose and amino acids across the portal-drained viscera (PDV) of growing pigs. Four Duroc×Landrance×Yolkshire cross-bred barrows (with an average body wt of 22.5 kg) were housed individually in stainless steel metabolism cages and trained to consume feed provided daily. After a 2-wk adaptation period, pigs were fitted with permanent catheters in the portal vein, mesenteric vein, and carotid artery. After a 13-d recovery period, pigs were assigned randomly into one of 4 treatment groups in a 4×4 Latin square design representing 4 cornstarch- and casein-based isocaloric and isonitrogenous diets containing 52.0% corn, 65.8% brown rice, 65.3% sticky rice, and 51.8% Hi-Maize 1043 (resistant starch). Pigs were fed 3 times daily at 07:30, 15:30 and 23:30 at a feeding level of >963 kJ DE/kg diet. Each diet was fed to the pig after a 6-d adaptation period. On d 7, blood samples were obtained simultaneously from the 3 catheters at 30 min prior to feeding and hourly for 8 h after feeding. Portal blood flow was measured using p-aminohippuric acid. Results showed that portal glucose absorption (expressed per 100 g feed intake) was lower (P < 0.05) for the resistantstarch diet compared with corn, stick rice and brown rice diets at all sampling times. In comparison with the corn diet, net portal glucose absorption was higher (P < 0.05) for the sticky rice and brown rice diets up to 4 h after feeding, but was reduced (P < 0.05) thereafter. Feeding the resistant-starch diet reduced (P < 0.05) the net portal absorption of total amino acids, particularly Pro, Leu, and Ile. The net appearance of total amino acids absorbed from the ileum differed (P < 0.05) among the treatment groups, and was 48.4, 63.8, 61.8, and 59.3%, respectively, for piglets fed the corn, brown rice, sticky rice, and resistant-starch diets. These findings indicate that dietary sources of starch affect intestinal absorption and metabolism of glucose and amino acids in growing pigs. Supported by funds from Chinese Academy of Sciences and China NSF. [ABSTRACT FROM AUTHOR]

The objectives of this study were to determine true phosphorus (P) digestibility and the gastrointestinal endogenous P outputs associated with brown rice at the ileal and the fecal levels in weanling pigs. Six Duroc x Large White x Landrace barrows, with an average initial BW 12.5 ± 0.6 kg, were fitted with a simple T-cannula at the distal ileum and fed six diets according to a 6 x 6 Latin square design. The diets were cornstarch-based and contained six levels of P (0.80, 1.36, 1.93, 2.49, 3.04 and 3.61 g/kg DMI) from brown rice. Chromic oxide (3.5 Nonruminant Nutrition: Dietary Influences in Nursery Pigs g/kg diet, on as-fed basis) was included as a digestibility marker. Each experimental period consisted of 9 d with 6-d adaptation and 3d collection of representative ileal digesta and fecal samples. True ileal and fecal P digestibility values and the ileal and fecal endogenous P outputs associated with brown rice were determined by the regression analysis technique. There were no differences (P > 0.05) in true P digestibility values (ileal, 57.7 ± 5.4 vs. fecal, 58.2 ± 5.9%, n = 36) and the endogenous P outputs (ileal, 0.812 ± 0.096 vs. fecal, 0.725 ± 0.083 g/kg DMI, n = 36) between the ileal and the fecal levels. In conclusion, about 58% of the total P in conventional brown rice is digested in weanling pigs. The large intestine does not play an role in the digestion and absorption of P associated with brown rice in the weanling pig. [ABSTRACT FROM AUTHOR]

Six Yorkshire x Landrace dry sows, with an average initial BW 200 kg and 5-7 parity, were housed individually and fed six diets (2 kg/d) according to a 6x6 Latin square design. The diets were soybean meal (SBM)-cornstarch-glucose based and contained six graded levels of Ca (1.58, 1.69, 1.94, 2.30, 2.88 and 3.65 g/kg DMI) and P (0.79, 1.91, 2.91, 4.04, 4.86 and 5.82 g/kg DMI). Chromic oxide (0.35%) was included in the diets as a digestibility marker. Each experimental period lasted 8 d with a 5-d adaptation and 3-d collection of fecal samples. True digestibility of Ca (27 ± 5.0%) and P (44.0 ± 4.5%) and the endogenous outputs of Ca (1.19 ± 0.12 g/kg DMI) and P (0.78 ± 0.17 g/kg DMI) associated with the solvent-extracted SBM for the sows were obtained by the simple linear regression analysis technique. In conclusion, Ca associated SBM was poorly digestible in sows. The endogenous fecal Ca output associated with SBM was relatively high in sows. [ABSTRACT FROM AUTHOR]

The arginine-family amino acids include glutamine, glutamate, aspartate, proline, ornithine, citrulline, and arginine. They can be inter-converted in mammals through inter-organ metabolism and cell-specific pathways, although the rates of their conversion vary greatly with precursors, species, developmental stages, and disease. Growing interests in these amino acids in nonruminant nutrition mainly arise from the emerging knowledge about: 1) their high concentrations in fetal and postnatal animals; 2) remarkable species-differences in their tissue-specific catabolism and synthesis; 3) their roles in regulating the metabolic processes essential for animal growth and development (e.g., fat metabolism, protein turnover, glucose homeostasis, nucleotide synthesis, and immune response) via the production of unique metabolites and signaling pathways; 4) their dietary supplementation as a practical, effective means to maintain tissue integrity, improve pregnancy outcomes, enhance animal growth, and optimize health; and 5) their role in reducing dietary protein content to minimize nitrogen excretion and environmental pollution. Recent examples for the beneficial application of the arginine-family amino acids to swine nutrition are: 1) preventing intestinal atrophy and improving growth performance in weanling pigs through dietary supplementation with glutamine; and 2) increasing growth performance in milk-fed piglets and finishing pigs as well as enhancing fetal survival and growth in gestating sows through dietary supplementation with arginine. Future holds great promise for the use of the arginine-family amino acids in increasing the efficiency of animal agriculture. Supported by grants from USDA/NRI, TAES, Texas Tech University, The Chinese Academy of Sciences, and China NSF. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the effects of exogenous zinc-metallothionein (Zn-MT) on anti-oxidative function in pork meat. After feeding a corn- and soybean meal-based diet for two weeks, 48 pigs (Duroc×Landrace×Chinese Black Pig) were assigned randomly into one of four treatment groups (12 pigs/group). Pigs in group 1 were maintained under non-stress conditions, whereas pigs in groups 2, 3 and 4 were aggressively handled for 25 min to produce stress. Then, pigs in groups 1 (control group) and 2 (negative control group) received intramuscular administration of saline, while pigs in groups 3 (low dose group) and 4 (high dose group) received 0.8 and 1.6 mg rabbit liver Zn-MT per kg body weight, respectively. Pigs were slaughtered at 3 and 6 h post-injection. Zn-MT treatment increased (P<0.05) the activities of superoxide dismutase (SOD) and glutathione-peroxidase (GSH-PX) while decreasing the concentration of malondialdehyde (MDA) in the liver. These responses were greater (P < 0.05) at 6 h than at 3 h post Zn-MT injection. Zn-MT treatment increased (P < 0.05) hepatic SOD mRNA levels in a time- and dosedependent manner, and decreased (P < 0.05) blood activities of glutamate-pyruvate transaminase and lactate dehydrogenase (indicators of tissue integrity). Zn-MT administration decreased (P < 0.05) lactic acid concentrations, thereby increasing (P < 0.05) the pH and water-holding capacity of the meat. Collectively, our results indicate that intramuscular administration of Zn-MT to preslaughter-stressed pigs improves tissue anti-oxidative ability and pork quality. Supported by funds from the Chinese Academy of Sciences and China NSF. [ABSTRACT FROM AUTHOR]

The experiment was conducted to determine the effects of dietary supplementation with the Chinese herb on growth performance, diarrhea incidents, serum biochemical parameters, and tissue integrity in weanling piglets. Sixty pigs were weaned at 21 days of age, housed individually and assigned randomly into one of three treatment groups (20 pigs/group), representing the corn- and soybean meal-based diets supplemented with 0 (control) or 0.2% Chinese herb or 0.02% Colistin (an antibiotic). The genus and species of the herbs used in the study were Astragalus membranaceus (Fisch.) Bge.var.mongholicus (Bge) hsiao; Acanthopanax senticosus (Rupr. Et Maxim) Harms; Codonopsis pilosula (Franch.) Nann.; Crataegus pinnatifida Bge.; and Salvia miltiorrhiza Bge. Pigs had free access to diets and drinking water. Feed intake and BW were measured weekly. Blood samples were obtained randomly from 5 piglets of each treatment group at wks 1, 2, 3, and 4 post-weaning. Results indicated that dietary supplementation with the Chinese herb for 4 wks increased (P < 0.05) ADG by 18.8% (432.1 vs 363.8 g), did not affect (P > 0.05) F:G (1.57 vs 1.62), and reduced (P < 0.05) diarrhea incidence by 40% in piglets, when compared with the control group. Dietary supplementation with Colistin did not affect (P > 0.05) ADG (385.9 vs 363.8 g)and had no effect (P > 0.05) on F:G (1.67 vs 1.62). At wk 1, serum concentrations of triglycerides in the herb-supplemented piglets were lower (P < 0.05) than those in the control group. At wk 2, the activity of serum creatine kinase (an indicator of tissue integrity) was lower (P < 0.05) in the herbsupplemented piglets in comparison with the other two groups. At wk 4, the activity of stomach amylase in the herb-supplemented piglets was higher (P < 0.05) than in the control and Colistin-supplemented piglets. These findings suggest that the Chinese herbal formula is a highly effective and safe feed additive for improving growth performance, preventing diarrhea, and protecting tissue integrity in weanling piglets. Supported by funds from the Chinese Academy of Sciences and China NSF. [ABSTRACT FROM AUTHOR]