Excessive Tryptophan and Phenylalanine Induced Pancreatic Injury and Glycometabolism Disorder in Grower-finisher Pigs.

BACKGROUND: The increase in circulating insulin levels is associated with the onset of type 2 diabetes (T2D), and the levels of branched-chain amino acids and aromatic amino acids (AAAs) are altered in T2D, but whether AAAs play a role in insulin secretion and signaling remains unclear. OBJECTIVES: This study aimed to investigate the effects of different AAAs on pancreatic function and on the use of insulin in finishing pigs. METHODS: A total of 18 healthy finishing pigs (Large White) with average body weight of 100 ± 1.15 kg were randomly allocated to 3 dietary treatments: Con, a normal diet supplemented with 0.68% alanine; Phe, a normal diet supplemented with 1.26% phenylalanine; and Trp, a normal diet supplemented with 0.78% tryptophan. The 3 diets were isonitrogenous. There were 6 replicates in each group. RESULTS: Herein, we investigated the effects of tryptophan and phenylalanine on pancreatic function and the use of insulin in finishing pigs and found that the addition of tryptophan and phenylalanine aggravated pancreatic fat deposition, increased the relative content of saturated fatty acids, especially palmitate (C16:0) and stearate (C18:0), and the resulting lipid toxicity disrupted pancreatic secretory function. We also found that tryptophan and phenylalanine inhibited the growth and secretion of ß-cells, downregulated the gene expression of the PI3K/Akt pathway in the pancreas and liver, and reduced glucose utilization in the liver. CONCLUSIONS: Using fattening pigs as a model, multiorgan combined analysis of the insulin-secreting organ pancreas and the main insulin-acting organ liver, excessive intake of tryptophan and phenylalanine will aggravate pancreatic damage leading to glucose metabolism disorders, providing new evidence for the occurrence and development of T2D.

In-vitro method and model to estimate methane emissions from liquid manure management on pig and dairy farms in four countries.

Methane (CH4) emissions from manure management on livestock farms are a key source of greenhouse gas emissions in some regions and for some production systems, and the opportunities for mitigation may be significant if emissions can be adequately documented. We investigated a method for estimating CH4 emissions from liquid manure (slurry) that is based on anaerobic incubation of slurry collected from commercial farms. Methane production rates were used to derive a parameter of the Arrhenius temperature response function, lnA', representing the CH4 production potential of the slurry at the time of sampling. Results were used for parameterization of an empirical model to estimate annual emissions with daily time steps, where CH4 emissions from individual sources (barns, outside storage tanks) can be calculated separately. A monitoring program was conducted in four countries, i.e., Denmark, Sweden, Germany and the Netherlands, during a 12-month period where slurry was sampled to represent barn and outside storage on finishing pig and dairy farms. Across the four countries, lnA' was higher in pig slurry compared to cattle slurry (p < 0.01), and higher in slurry from barns compared to outside storage (p < 0.01). In a separate evaluation of the incubation method, in-vitro CH4 production rates were comparable with in-situ emissions. The results indicate that lnA' in barns increases with slurry age, probably due to growth or adaptation of the methanogenic microbial community. Using lnA' values determined experimentally, empirical models with daily time steps were constructed for finishing pig and dairy farms and used for scenario analyses. Annual emissions from pig slurry were predicted to be 2.5 times higher than those from cattle slurry. Changing the frequency of slurry export from the barn on the model pig farm from 40 to 7 d intervals reduced total annual CH4 emissions by 46 %; this effect would be much less on cattle farms with natural ventilation. In a scenario with cattle slurry, the empirical model was compared with the current IPCC methodology. The seasonal dynamics were less pronounced, and annual CH4 emissions were lower than with the current methodology, which calls for further investigations. Country-specific models for individual animal categories and point sources could be a tool for assessing CH4 emissions and mitigation potentials at farm level.

Effects of Dietary Supplementation of Quillaja Saponin or Phytase on the Growth Performance, Nutrient Digestibility, Faecal Gas Emissions, and Carcass Grade in Growing-Finishing Pigs.

This experiment aimed to evaluate the effects of low doses of Quillaja saponin (QS) or phytase (PHY) on growth performance, nutrient digestibility, faecal gas emissions, and carcass grade in growing-finishing pigs. A total of 72 pigs (Landrace × Yorkshire × Duroc), each weighing 25.82 ± 1.68 kg, were selected and randomly assigned to three treatment groups. Each group had six replicates, with four pigs per pen, and the allocation was based on the four initial body weight and sex of the pigs. They were randomly divided into the following three diet groups: the basal diet as a control (CON) group, the basal diet + 0.02% PHY; and the basal diet + 0.01% QS. The experiment period lasted for 110 days. The results of adding 0.01% QS to the basal diet of pigs show that it can significantly increase the body weight (BW) of growing-finishing pigs on the 110th day (p < 0.05). QS can significantly increase the average daily weight gain (ADG) on Days 80-110 of the experiment (p < 0.05). QS can significantly increase the total average daily weight gain (TADG) of growing-finishing pigs during the entire experimental period (p < 0.05) and has a tendency to improve the average daily feed intake and feed conversion rate during the entire experimental period. However, QS has no significant effect on pig nutrient digestibility and carcass grade. In addition, we also found that QS has a tendency to reduce carbon dioxide emissions. However, adding 0.02% PHY to the basal diet of growing-finishing pigs can only increase the TADG during the entire experimental period. Throughout the experiment, adding PHY to the diet had no significant impact on the nutrient digestibility, faecal gas emissions, and carcass grade of growing-finishing pigs. In summary, adding QS to feed can significantly improve the growth performance of growing-finishing pigs, and has a tendency to improve faecal gas emissions. PHY can only improve the growth performance of growing-finishing pigs.

Dietary grape seed proanthocyanidin extract supplementation improves antioxidant capacity and lipid metabolism in finishing pigs.

Grape seed proanthocyanidin extract (GSPE) plays a significant role in body health, including improving antioxidant capacity and maintaining lipid metabolism stability. However, whether dietary GSPE supplementation can improve lipid metabolism in finishing pigs remains unclear. Here 18 castrated male Duroc × Landrace × Yorkshire finishing pigs were randomly divided into three groups with six replicates and one pig per replicate. Pigs were fed a basal diet (control), a basal diet supplemented with 100 mg/kg GSPE, or a basal diet supplemented with 200 mg/kg GSPE for 30 days. Antioxidant analysis showed that dietary 200 mg/kg GSPE supplementation increased glutathione, total antioxidant capacity and glutathione peroxidase levels, and reduced malondialdehyde levels in serum, muscle and liver. Dietary 200 mg/kg GSPE supplementation also upregulated the mRNA and protein levels of nuclear-related factor 2 (Nrf2). Lipid metabolism analysis showed that dietary GSPE supplementation increased serum high-density lipoprotein cholesterol levels and reduced serum triglyceride and total cholesterol levels. Besides, GPSE upregulated the mRNA expression of lipolysis- and fatty acid oxidation-related genes downregulated the mRNA expression of lipogenesis-related genes, and activated the AMPK signal in finishing pigs. Together, we provided evidence that dietary GSPE supplementation improved the antioxidant capacity and lipid metabolism in finishing pigs.

Multiple amino acid supplementations to reduce dietary protein for pigs during early and late finisher periods under commercial conditions.

BACKGROUND: With the easy availability and competitive prices of crystalline amino acids (AAs), the reduction of dietary crude protein (CP) for pigs during early and late finisher periods is possible under commercial conditions. Two experiments were conducted to assess the growth efficiency of early and late-finishing pigs fed with protein-restricted diets supplemented with Lys, Met, Thr, Trp, Val, Ile and His. In Experiment 1, 840 early finishing pigs were allocated to four dietary treatments with CP levels designed at 150, 142, 134, and 126 g kg-1 diet. In Experiment 2, 768 late-finishing pigs were allotted to four dietary treatments providing CP levels at 140, 130, 120, and 110 g kg-1 diet. RESULTS: In Experiment 1, the data showed that CP levels could be decreased from 150 to 126 g kg-1 without adversely affecting performance of early finishing pigs as no significant difference was observed for final bodyweight, average daily gain (ADG), feed to gain ratio (F:G), or average daily feed intake (ADFI). In Experiment 2, late-finishing pigs consuming 120 g kg-1 CP tended to have the highest ADG and lowest F:G whereas those fed the 110 g kg-1 CP diet showed the opposite trend. Based on quadratic analysis, the optimum CP levels to maximize ADG and minimize F:G were 126 and 127 g kg-1 , respectively. CONCLUSION: These findings showed that dietary CP levels could be decreased to 126 g kg-1 for early finishing pigs while improved performance was noted in late-finishing pigs consuming 120 g kg-1 CP. © 2023 Society of Chemical Industry.

Effects of dietary l-theanine supplementation on pork quality and muscle fiber type transformation in finishing pigs.

BACKGROUND: This experiment aimed to investigate effects of dietary l-theanine supplementation on pork quality and muscle fiber type transformation in finishing pigs. In a 30-day experiment, 18 healthy Duroc × Landrace × Yorkshire (DLY) pigs with an average body weight of 86.03 ± 0.83 kg were randomly divided into three groups (a basal diet or a basal diet supplemented with 500 and 1000 ppm l-theanine, respectively), with six duplicates and one pig per replicate. RESULTS: The results showed that dietary 1000 ppm l-theanine supplementation significantly reduced (P < 0.05) b*24 h and drip loss. Dietary 1000 ppm l-theanine supplementation significantly increased (P < 0.05) slow myosin heavy chain (MyHC) protein expression and the percentage of slow-twitch fibers, as well as significantly decreased (P < 0.05) fast MyHC protein expression and the percentage of fast-twitch fibers, accompanied by an increase in succinate dehydrogenase (SDH) and malate dehydrogenase (MDH) activities and a decrease in lactate dehydrogenase (LDH) activity. In addition, the adenosine monophosphate (AMP)-activated protein kinase (AMPK) signaling pathway was activated by l-theanine. CONCLUSION: Together, this study demonstrated for the first time that dietary supplementation of 1000 ppm l-theanine can improve pork color and drip loss and promote muscle fiber type transformation from fast-twitch to slow-twitch in finishing pigs. © 2022 Society of Chemical Industry.

Effects of low protein diet with a balanced amino acid pattern on growth performance, meat quality and cecal microflora of finishing pigs.

BACKGROUND: The present study aimed to investigate the effects of low protein diets balanced with four amino acids on growth performance, meat quality and cecal microflora of finishing pigs. Fifty-four healthy hybrid barrows (Duroc × Landrace × Yorkshire) with an average body weight of 70.12 ± 4.03 kg were randomly assigned to one of the three dietary treatments with six replicate pens per treatment (three barrows per pen). The three dietary treatments included a normal protein diet (NP), a low protein diet (LP) and a very low protein diet (VLP). RESULTS: The average daily gain, average daily feed intake and feed conversion ratio of pigs were not significantly changed with the LP and VLP diets compared to the NP diet (P > 0.05). The water holding capacity and shear force of longissimus dorsi muscle were decreased, whereas the intramuscular fat content of the longissimus dorsi muscle was increased (P < 0.05) in pigs fed with the LP and VLP diets compared to the NP diet. The contents of saturated fatty acids in muscle were decreased (P < 0.05), whereas the content of polyunsaturated fatty acids in muscle was increased (P < 0.01) with the VLP diet compared to the NP diet. The contents of histamine, spermidine, spermine and tyramine of muscle were decreased with the VLP diet compared to the NP diet (P < 0.05). The relative abundance of Turicibacter, Terrisporobacter, Clostridium_sensu_stricto_1 and UCG-005 was higher (P < 0.05), whereas the relative abundance of Lactobacillus and Streptococcus was lower (P < 0.05) in pigs fed with the LP and VLP diets compared to the NP diet. Based on the correlation of cecal microbiota and cecal biogenic amine, the contents of tyramine, spermidine and histamine were negatively correlated with the abundance of Terrisporobacter (P < 0.01) and the content of histamine was positively correlated with the abundance of Lactobacillus (P < 0.01). CONCLUSION: Balanced with four essential amino acids, the VLP diet with crude protein levels decreased by > 4% increased the intramuscular fat content, changed the fatty acid and amino acid composition of longissimus dorsi muscle and the profile of cecum microbiota, and reduced the content of cecum bioamine, with no negative effect on the growth performance of pigs. © 2022 Society of Chemical Industry.

Effects of sweet potato vine silage supplementation on meat quality, antioxidant capacity and immune function in finishing pigs.

Sweet potato vine, the byproduct of sweet potato, has a high nutritional value. Silage is an effective solution for nutrient preservation. This article explored the effects of sweet potato vine silage (SPVS) supplementation on meat quality, antioxidant capacity and immune function in finishing pigs. One hundred and eighty finishing pigs (Berkshire × Licha Black) with a body weight of 74.54 ± 3.32 kg were randomly divided into three groups. The three groups were separately fed basal diet (Ctrl), Ctrl supplemented with 2.5% SPVS (LSPVS) or 5% SPVS (HSPVS) on a dry matter basis. Results showed that the eye muscle area in the LSPVS group was significantly increased. The carcass weight in the HSPVS was significantly reduced compared with Ctrl. For the meat quality, only cooking loss in both HSPVS and LSPVS was reduced while other indexes had no significant differences. For the antioxidant capacity, the hepatic level of glutathione (GSH) peroxidase (GSH-PX) was significantly upregulated in LSPVS but downregulated in HSPVS. In the serum, HSPVS decreased GSH level and increased GSH-PX level. HSPVS significantly reduced hepatic interleukin-1ß (IL-1ß) levels and LSPVS significantly reduced IL-12 levels and increased IL-8 and IL-6 levels. Moreover, HSPVS and LSPVS promoted the secretion of immunoglobulin M (IgM) and IgG in the serum. Our data showed that low-dose SPVS supplementation improved carcass traits and high-dose SPVS supplementation increased immune function in finishing pigs, which provides a new alternative to improve animal health.

Effects of slaughter age on carcass traits and meat quality of crossbred (Duroc × Landrace × Yorkshire) finishing pigs.

Thirty castrated Duroc × Landrace × Yorkshire (DLY) pigs were randomly divided into three groups and slaughtered at 180, 210, and 240 days of age, respectively. Here, we found that the live weight, carcass weight, carcass length, dressing percentage, eye muscle area, backfat deposit, muscle yellowness b* value, drip loss, and cooking loss increased significantly, and the muscle pH 45 min value decreased dramatically as the slaughter age of DLY pigs extended. Moreover, increasing the slaughter age of DLY pigs could obtain higher n-3 polyunsaturated fatty acid (PUFA) percentage, crude protein, essential amino acids (EAA) contents and EAA/NEAA level, and lower n-6/n-3 PUFA level and antioxidant capacity. Together, this study suggests that the older slaughter age improves the carcass traits and nutritional value of pork, but leads to a significant decrease in pork sensory quality in DLY finishing pigs.

Effects of dietary dihydromyricetin supplementation on intestinal barrier and humoral immunity in growing-finishing pigs.

In this study, we investigated the effect of dietary dihydromyricetin (DHM) supplementation on intestinal barrier and humoral immunity in growing-finishing pigs. The data showed that dietary DHM supplementation improved jejunal barrier function by upregulating the protein expressions of Occludin and Claudin-1 and the mRNA levels of MUC1 and MUC2. Dietary DHM supplementation increased the amylase, lipase, sucrase and maltase activities and the mRNA expression of nutrient transporter (SGLT1, GLUT2, PepT1) in the jejunum mucosa. Dietary DHM supplementation significantly reduced the E. coli population in the cecum and colon and increased the Lactobacillus population in the cecum. In addition, dietary DHM supplementation increased the contents of butyric acid and valeric acid in cecum and colon. In serum, dietary DHM supplementation reduced interleukin-1ß (IL-1ß) content and increased interleukin-10 (IL-10), Immunoglobulin M (IgM) and Immunoglobulin A (IgA) contents (p < 0.05). In addition, compared with the control group, dietary DHM supplementation improved secretory immunoglobulin A (sIgA) and interleukin-10 (IL-10) contents and down-regulated TNF-α protein expression in jejunum mucosa (p < 0.05). Together, this study demonstrated that dietary DHM supplementation improved intestinal barrier function, digestion and absorption capacity and immune function in growing-finishing pigs.

Effects of dietary lycopene supplementation on intestinal morphology, antioxidant capability and inflammatory response in finishing pigs.

In this study, eighteen healthy Duroc × Landrace × Yorkshire barrows with initial body weight of 63.89 ± 1.15 kg were randomly allotted to three treatments and fed a basal diet or a basal diet supplemented with 100 mg/kg and 200 mg/kg lycopene, respectively. Data showed that villus height to crypt depth ratio increased with 200 mg/kg lycopene (p < 0.05) in the jejunum. In duodenum, the malondialdehyde content was decreased (p < 0.05) in 100 and 200 mg/kg lycopene groups. Furthermore, in the jejunum, dietary 100 and 200 mg/kg lycopene supplementation increased (p < 0.05) catalase activity. In the duodenum, interleukin-1ß (IL-1ß), nuclear factor-κB and tumor necrosis factor-α contents were decreased (p < 0.05) in 200 mg/kg lycopene group. In the jejunum, IL-1ß content was reduced (p < 0.05) and IL-1ß mRNA expression was down-regulated (p = 0.046) in 200 mg/kg lycopene group. Additionally, claudin-1 mRNA and protein levels in 200 mg/kg group were also increased (p < 0.05). These results indicated that dietary lycopene supplementation could maintain intestinal health, which was associated with improving intestinal morphology, enhancing tight junction function, inhibiting inflammatory response, and elevating antioxidant capacity in finishing pigs.

Dietary stevia residue extract supplementation improves the performance and antioxidative capacity of growing-finishing pigs.

BACKGROUND: Improper disposal of stevia residue causes environmental pollution and waste of resources. The extract of stevia residue is rich in chlorogenic acid and isochlorogenic acids, and has a great potential in livestock and poultry breeding. Therefore, this study aimed to investigate the effects of dietary stevia residue extract (SRE) supplementation on the performance, meat quality, antioxidative capacity and gut microbiota in growing-finishing pigs. RESULTS: The results showed that increasing the concentration of SRE supplementation linearly increased (P < 0.05) body weight from day 1 to 35. Supplementation with SRE significantly increased (P < 0.05) average daily gain (ADG) from day 1 to 75. 100 mg kg-1 SRE supplementation significantly increased (P < 0.05) hot carcass weight and gastric index. Moreover, increasing the concentration of SRE linearly increased (P < 0.05) the score of appearance of longissimus thoracis, as well as serum albumin, triglyceride and high-density lipoprotein cholesterol content. Further study found that increasing the concentration of SRE linearly increased (P < 0.05) serum total superoxide dismutase activity, and showed a significant quadratic relationship (P < 0.05) with activity of serum catalase, while linearly decreasing (P < 0.05) muscle malondialdehyde (MDA) content. Furthermore, supplementation with 100 mg kg-1 SRE significantly decreased (P < 0.05) serum MDA content, while 600 and 800 mg kg-1 SRE supplementation significantly decreased (P < 0.05) muscle MDA content. However, SRE supplementation had no significant effect on gut microbiota (P > 0.05). CONCLUSION: These data indicated that dietary SRE supplementation improves the performance and antioxidative capacity of growing-finishing pigs. We recommend that the optimal supplemental level of SRE in the diet of growing-finishing pigs is 100 mg kg-1 . © 2022 Society of Chemical Industry.

Balanced branched-chain amino acids modulate meat quality by adjusting muscle fiber type conversion and intramuscular fat deposition in finishing pigs.

BACKGROUND: Pork is an important food for humans and improving the quality of pork is closely related to human health. This study was designed to investigate the effects of balanced branched-chain amino acid (BCAA)-supplemented protein-restricted diets on meat quality, muscle fiber types, and intramuscular fat (IMF) in finishing pigs. RESULTS: The results showed that, compared with the normal protein diet (160 g kg-1 crude protein), the reduced-protein diet (120 g kg-1 crude protein) supplemented with BCAAs to the ratio of 2:1:2 not only had higher average daily gain (P < 0.05) and carcass weight (P < 0.05) but also improved meat tenderness and juiciness by decreasing shear force (P < 0.05) and increasing water-holding capacity (P < 0.05). In particular, this treatment showed higher (P < 0.05) levels of phospho-acetyl-CoA carboxylase (P-ACC) and peroxisome proliferation-activated receptor-γ (PPARγ), and lower (P < 0.05) levels of P-adenosine 5'-monophosphate (AMP)-activated protein kinase (P-AMPK), increasing the composition of IMF and MyHC I (P < 0.05) in the longissimus dorsi muscle (LDM). In terms of health, this group increased eicosapentaenoic acid (EPA) (P < 0.01) and desirable hypocholesterolemic fatty acids (DHFA) (P < 0.05), and decreased atherogenicity (AI) (P < 0.01) and hypercholesterolemic saturated fatty acids (HSFA) (P < 0.05). CONCLUSION: Our findings suggest a novel role for a balanced BCAA-supplemented restricted protein (RP) diet in the epigenetic regulation of more tender and healthier pork by increasing IMF deposition and fiber type conversion, providing a cross-regulatory molecular basis for revealing the nutritional regulation network of meat quality. © 2021 Society of Chemical Industry.

Effects of Achyranthes japonica extract on the performance of finishing pigs fed diets containing palm kernel meal and rapeseed meal as a partial alternative to soybean meal.

A total of 120 finishing pigs with an average initial body weight of 49.72 ± 0.08 kg (mean ± SD) were used in a 10 weeks trial. Pigs were randomly allotted into one of four dietary treatments (6 replicate pen/treatment, 5 pigs/pen). The nutritional dietary treatments were corn, soy bean meal, palm- kernel meal, and rapeseed meal based basal diets supplemented with 0, 0.05, 0.10, and 0.20% of Achyranthes japonica extract (AJE). Dietary inclusion of AJE supplementation had trend to increase the body weight and average daily gain of pigs at week 10 and the overall experimental period, respectively. The graded level of AJE supplement had increase the total track digestibility dry matter (p = 0.067) only at week 5 while nitrogen and energy digestibility (p < 0.05) was linearly increased at both weeks 5 and 10. During week 10, pigs fed with an increased level of AJE supplementation had linearly increase (p < 0.05) fecal Lactobacillus counts. In addition, AJE supplementation in the diet of finishing pigs had linearly decreased (p > 0.05) NH3 emission of gas and trend to decrease total mercaptans during week 10. Dietary inclusion of AJE supplement resulted in a linear increase in the blood protein concentration level. Moreover, drip loss was linearly reduced on day 5 and day 7 (p > 0.05) post slaughter in finishing pigs fed with gradually increased levels of AJE supplementation. During weeks 5 and 10, pigs fed with graded levels of AJE supplementation had linearly increase (p < 0.05) the backfat thickness and lean meat percentage. Therefore we conclude that dietary inclusion of AJE with palm kernel meal and rapeseed meal could be benificial to enhance the growth performance, nutrient digestibility, fecal microbial, blood prolife, meat quality and reduced fecal gas emission in finishing pigs.

Meta-analysis of energy intake of growing-finishing pigs in China.

Data from 655 treatments of 116 studies were used in a meta-analysis to determine the daily digestible energy (DE), metabolizable energy (ME) and net energy (NE) intake of Chinese growing-finishing pigs, and to predict feed efficiency responses to change in dietary DE, ME and NE. Three alternative functions (i.e., polynomial, Bridges and asymptotic function) were employed for fitting daily DE, ME or NE intakes to mean body weight. The results showed that the three models from the current study provided reasonable fit (all R2  > 0.83) for the energy intake data. However, under the same energy system, the polynomial function had the smallest Akaike's information criteria (AIC) and residual standard deviation (RSD), followed by Bridges and asymptotic functions. The three model-generated energy intakes of growing pigs were significantly less than that of the Chinese Feeding Standard of Swine, but similar to that of the National Research Council (2012), while the values of finishing pigs were greater than both standards. Compared with those that predict feed efficiency based on DE or ME, the equation with NE as a predictor had the minimized AIC and RSD. It was also found that feed efficiency increased with increasing dietary energy density (DED), but this response varied with pig body weight, and the lighter pigs were more sensitive to DED than heavier pigs.

Effects of dietary plant essential oil supplementation on growth performance, nutrient digestibility and meat quality in finishing pigs.

This study was aimed to explore the effects of dietary plant essential oil (PEO) supplementation on growth performance and meat quality in finishing pigs. A total of eighteen Duroc × Landrace × Yorkshire finishing barrows with an average initial body weight of 79.86 ± 1.94 kg were randomly assigned to CON group (fed with a basal diet) and PEO group (fed with the basal diet containing 200 mg/kg PEO) with 9 replicates per treatment. The trial lasted for 42 days. The results showed that dietary PEO supplementation significantly increased ADG during phase I (1-21 days) and the overall experimental period (p < 0.05), tended to increase ADFI in phase II (22-42 days) and the overall experimental period (p = 0.09), decreased F/G in phase I (p < 0.05) and tended to decrease F/G during the overall experimental period (p = 0.08). Meanwhile, compared to the CON group, the digestibility of DM, GE and EE in the PEO group was improved remarkably (p < 0.05). PEO supplementation also significantly improved T-AOC and lowered MDA content in longissimus dorsi (p < 0.05), tended to increase the activity of T-SOD (p = 0.06). A higher IMF content (p = 0.09) and a lower shear force (p = 0.08) of longissimus dorsi were found in the PEO group than that in CON group (p = 0.09). Furthermore, pigs fed the PEO diet showed higher mRNA abundances of GLUT4, LPL, CPT-1, CD36, FABP and LDL-R in the liver, and GLUT4 and FAS in the longissimus dorsi (p < 0.05). In conclusion, PEO fed to finishing pigs improved the growth performance and nutrient digestibility. Furthermore, PEO supplementation had the potential role to improve pork quality by increasing the antioxidant capacity and IMF content, and decreasing the shear force of longissimus dorsi to a certain extent.

Dietary addition of fermented sorghum distiller's dried grains with soluble improves carcass traits and meat quality in growing-finishing pigs.

The fermented sorghum distiller's dried grain with soluble (FS-DDGS) contains numerous nutrients, yet its nutritional effects on growing-finishing pigs remain unclear. The present study evaluated the effects of dietary FS-DDGS addition on growth performance, carcass traits, and meat quality in growing-finishing pigs. A total of 48 healthy male crossbred (Large White × Landrace × Duroc) barrows with initial body weight (BW) of 39.95 ± 2.15 kg were allocated to one of four dietary treatments (12 pigs per treatment). The dietary treatments were as follows: basal diet without (FS-DDGS0 group) or with 50 g/kg (FS-DDGS50 group), 100 g/kg (FS-DDGS100 group), or 150 g/kg (FS-DDGS150 group) FS-DDGS, respectively. Results showed that there were no significant differences in the final BW, average daily gain, average daily feed intake, and feed to gain ratio among these four groups. However, dietary FS-DDGS addition increased (linear, P < 0.05) the pH24h value, contents of ash, crude protein, and proline in Longissimus dorsi muscle, and alanine, arginine, aspartic acid, glutamic acid, isoleucine, leucine, lysine, serine, and tyrosine in Biceps femoris (BF) muscle, when compared with the control group. In addition, dietary FS-DDGS addition decreased (linear, P < 0.05) the drip loss, yellowness (b*) value, and lightness (L*) value, while quadratically improved (P < 0.05) the total bone percentage and glycine and proline contents in BF muscle compared with the control group. Collectively, these findings suggested that dietary FS-DDGS addition could improve the carcass traits and meat quality in growing-finishing pigs although further research is needed to explore the underlying mechanisms.

Effects of apple polyphenols on myofiber-type transformation in longissimus dorsi muscle of finishing pigs.

This study aimed to investigate effects of apple polyphenols (APPs) on myofiber-type transformation in longissimus dorsi muscle of finishing pigs and its mechanism. In this study, 36 healthy castrated Duroc × Landrace × Yorkshire pigs with an average body weight of 71.25 ± 2.40 kg were randomly divided into three treatment groups (control, 0.04% APPs, 0.08% APPs). The experiment lasted for 49 days. Results showed that dietary APP supplementation increased the protein expression of MyHC I and the activities of succinic dehydrogenase and malate dehydrogenase, as well as decreased the protein expression of MyHC IIb and the activity of lactate dehydrogenase, suggesting that APPs promoted muscle fiber-type transformation from fast-twitch to slow-twitch in finishing pigs. We also showed that dietary 0.08% APP supplementation increased the expressions of mitochondrial biogenesis and function-related proteins PGC-1α, Sirt1 and Cytc. In addition, dietary supplementation with 0.08% APPs increased the activities of T-SOD, GSH-PX and CAT and decreased the MDA content. Together, we provided the first evidence that APP promotes muscle fiber-type transformation from fast-twitch to slow-twitch in finishing pigs, which may be achieved by improving the mitochondrial biogenesis and function and increasing the antioxidant capacity of skeletal muscle.

Dietary supplementation with Moringa oleifera and mulberry leaf affects pork quality from finishing pigs.

Moringa oleifera and Morus alba leaves are nutritious non-traditional feed ingredients containing bioactive substances. This study was to evaluate the potential application of dietary Moringa and Morus leaf powder on the growth traits, carcass characteristics and meat quality of finishing pigs. Moringa did not alter growth performance or carcass characteristics, but it decreased meat b* value, increased MyHCIIa and decreased MyHCIIx mRNA levels, and increased CP and concentrations of Ala, Thr, Ile, Lys and Pro in longissimus thoracis. Morus increased final BW, ADFI and ADG, decreased F/G ratio, improved slaughter weight, carcass weight, carcass yield and meat a* value, and decreased shear force, drip loss, MyHCIIx and MyHCIIb mRNA levels, and increased MyHCI and MyHCIIa mRNA levels. Morus also increased CP, Glu, Gly, Ala, Arg, Ile, Phe, Pro, Ser, Tyr and Asp, and C16:1, C18:1n9c, C20:4n6, C18:3n3, C20:3n3, C22:1n9 and n-3 PUFA, but decreased C12:0 and C16:0. In summary, Morus improved the parameters and held great potential as an unconventional feed crop.

Effects of acute heat stress on intestinal microbiota in grow-finishing pigs, and associations with feed intake and serum profile.

AIMS: This study was conducted to assess the effects of acute heat stress (HS) on intestinal microbiota, and the associations with the changes in feed intake (FI) and serum profile. METHODS AND RESULTS: Twenty four individually housed pigs (Duroc × Large White × Landrace, 30 ± 1 kg body weight) were randomly assigned to receive one of three treatments (8 pigs/treatment): (i) thermal neutral (TN) conditions (25 ± 1°C), (ii) HS conditions (35 ± 1°C), (iii) pair-feeding (PF) with HS under TN conditions. After 24-h treatment, pigs were monitored to assess FI, and samples of serum and faeces were collected to investigate serum profile, microbial composition and short chain fatty acids (SCFAs). The results showed that HS decreased (P < 0·05) FI compared with the TN group. Compared with TN group, HS changed the serum profile by affecting biochemical parameters and hormones related with energy metabolism and stress response; immune indicators were also altered in HS group. Most of changes in serum profile were independent of FI reduction. Additionally, HS shifted the diversity and composition of faecal microbial community by increasing (P < 0·05) Proteobacteria and decreasing (P < 0·05) Bacteroidetes. Moreover, HS decreased (P < 0·05) the concentrations of propionate, butyrate, valerate, iso-valerate and total SCFAs in faeces in an FI-independent manner. Furthermore, the Spearman correlation analysis implied that changes of serum profile have potential correlation with alterations of faecal microbiota and their SCFAs metabolites in acute HS-treated grow-finishing pigs. CONCLUSIONS: Metabolism disorders caused by 24-h acute HS associated with changes of faecal microbiota and their SCFAs metabolites in an FI-independent manner in grow-finishing pigs. SIGNIFICANCE AND IMPACT OF THE STUDY: These results give us a new insight of the intestinal damage caused by acute HS and the underlying mechanisms.