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This study was conducted to evaluate the effects of dietary resveratrol supplementation on growth performance, meat quality, serum lipid profiles, intramuscular fat (IMF) deposition, and the expression levels of several lipid metabolism-related miRNAs and genes in growing-finishing pigs. A total of 36 healthy crossbred pigs (Duroc × Landrace × Yorkshire) with an average initial BW of 24.67 ± 3.49 kg were randomly divided into two groups and fed either with a basal diet (CON) or basal diet containing 600 mg/kg resveratrol (RES). The trial lasted for 119 d. Resveratrol had no significant effect on growth performance and carcass characteristics. However, the concentrations of serum triglyceride, total cholesterol, low-density lipoprotein cholesterol, and very low-density lipoprotein were lower in RES group than those of CON group (P < 0.05). Dietary resveratrol supplementation increased the IMF content in longissimus dorsi (P < 0.05), up-regulated mRNA abundances of peroxisome proliferator-activated receptor γ, fatty acid synthase, acetyl-CoA carboxylase, and lipoprotein lipase (P < 0.05), while downregulated mRNA abundances of carnitine palmitoyl transferase-1, sirtuin 1, and peroxisome proliferator-activated receptor α (P < 0.05) in LM. In addition, resveratrol enhanced (P < 0.05) the expression of ssc-miR-181a, ssc-miR-370, and ssc-miR-21 and reduced (P < 0.05) the expression of ssc-miR-27a in longissimus dorsi. These results indicated that dietary resveratrol supplementation significantly improved IMF content and decreased serum lipids levels, which might be related with the changes in ssc-miR-181a, ssc-miR-370, ssc-miR-21, ssc-miR-27a and their downstream genes expression., (© The Author(s) 2019. Published by Oxford University Press on behalf of the American Society of Animal Science. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

This study was conducted to investigate the effects of benzoic acid (BA) on growth performance, intestinal development and intestinal barrier function in weaned pigs. Ninety weaned pigs were randomly assigned to one of three treatments: a basal diet (CON), the basal diet supplemented with 2000 mg/kg benzoic acid (BA1) and 5000 mg/kg benzoic acid (BA2). At the end of days 14 and 42, six pigs per treatment were randomly selected to collect plasma and intestinal samples. Results showed that BA supplementation not only improved final body weight, daily growth and feed conversion ratio from days 15 to 42 and days 1 to 42, but also decreased the activity of plasma diamine oxidase (day 42) and the pH values of jejunal contents (day 14) (p < 0.05). Ileal Bacillus populations (day 14) were increased by BA, while Escherichia coli counts in the ileum and caecum (day 42) were decreased (p < 0.05). Higher Lactobacillus counts occurred in the ileum (day 14, 42) of BA1-fed piglets as compared to CON and BA2-fed piglets (p < 0.05). In addition, BA supplementation increased the ratio of villus height to crypt depth (day 14, 42) and decreased the crypt depth (day 14) (p < 0.05). Growth-stimulating factors (insulin-like growth factor-1, day 42; insulin-like growth factor-1 receptor, day 14, 42) and tight junction protein (occludin, day 14, 42; zonula occludens-1, day 42)-related gene mRNA levels were upregulated in the jejunum of piglets fed BA diets (p < 0.05). In conclusion, this study provides the first evidence that BA has beneficial effects on intestinal development and intestinal barrier function of weaned pigs, which can partly explain why growth performance of pigs was improved by dietary BA supplementation., (Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.)

MicroRNAs (miRNAs) are a class of small non-coding RNAs that negatively regulate gene expression of target messenger RNAs (mRNAs) and miRNAs have been proven to play vital roles in skeletal muscle development. The miRNA-499-5p has been reported to be negatively related with the expression of Sox6, a critical transcription factor for the maintenance of fast-twitch skeletal muscle. In this study, we amplified a length of 2012-bp mRNA that contains a 1512-bp porcine Sox6 (pSox6) 3'UTR from skeletal muscle of a Duroc×Landrace×Yorkshire pig. By luciferase reporter assay we verified that pSox6 is a target of miR-499-5p. In extensor digitorum longus and Soleus muscles of pigs, the expression levels of miR-499-5p and pSox6 mRNA were also inversely correlated. Besides, overexpression of miR-499-5p in porcine satellite cells promoted the expression of MyHC I and MyHC IIa mRNA, along with a reduction of pSox6 mRNA. Taken together, these results indicate that miR-499-5p may facilitate the oxidative myofibers formation by downregulating pSox6 expression.

Montmorillonite (MMT) is widely used as a mycotoxin adsorbent in animal feeds, but its safety remains unclear. This study was conducted to investigate the safety of MMT supplementation in diets fed to starter pigs. A total of 120 32-d-old piglets (initial weight, 8.0 ± 0.9 kg) were randomly allotted into dietary treatments with graded MMT levels (0 [FS 0], 0.5% [FS 0.5], 1.0% [FS 1.0], 2.5% [FS 2.5], and 5.0% [FS 5.0]) with 6 replicate pens per treatment and 4 pigs per pen. All diets were fed for 28 d. As the MMT level increased, ADG and G:F changed in a linear and quadratic manner, while ADFI was linearly decreased ( > 0.05). Compared with FS 0, ADG, ADFI, and G:F of pigs in FS 1.0 increased ( < 0.05). However, the ADFI in pigs of FS 5.0 was lower than that in pigs of FS 0 ( < 0.05). The relative liver weight activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) changed in a linear and quadratic manner ( < 0.05). Compared with FS 0, pigs in FS 2.5 and FS 5.0 had a greater serum ALT ( < 0.05), while AST activity significantly increased in pigs of FS 5.0 ( < 0.05). Dietary MMT supplementation decreased serum Mg content in a linear and quadratic manner ( < 0.05), while Zn and Cu contents were linearly decreased ( < 0.05). Serum Zn and Cu contents of pigs in FS 0.5, FS 2.5, and FS 5.0 groups were lower than those in the control. Pigs fed with 2.5% and 5% MMT showed hepatic histopathological changes, including swelling, granular and vesicular degeneration, and apparent vacuolar degeneration. In addition, the content of serum total antioxidant capacity (T-AOC) and activity of glutathione peroxidase (GSH-PX) decreased in a linear and quadratic manner ( < 0.05). Compared to the control, 5.0% MMT significantly increased piglets' serum malondialdehyde (MDA) concentration and decreased GSH-PX activity ( < 0.05). T-AOC concentration in the pigs fed 2.5% and 5.0% MMT was lower than that in the control group ( < 0.05). Serum superoxide dismutase (SOD) activity changed in a quadratic manner ( < 0.05). Piglets in FS 1.0 showed a higher SOD activity when compared with the control ( < 0.05). These results indicate that supplementation of MMT higher than 1.0% can negatively affect liver structure and serum mineral content, and 5.0% MMT supplementation would also decrease feed intake, aggravate liver damage, and reduce the antioxidant capacity of starter pigs. Therefore, excess supplementation of MMT is not safe in starter pigs.

The objective of this study was to evaluate the effects of dietary addition of spray-dried chicken plasma (SDCP) as a replacement for spray-dried porcine plasma (SDPP) on serum biochemistry, intestinal barrier function, immune parameters, and the expression of intestinal development-related genes in weaning pigs. One hundred and forty-four 25-d-old weaning piglets with BW of 6.43 ± 0.39 kg were randomly allotted to 1 of 4 dietary treatments: 1) CON (basal diet; control), 2) SDPP (containing 5% SDPP), 3) SDPP + SDCP (containing 2.5% SDPP and 2.5% SDCP), and 4) SDCP (containing 5% SDCP). After a 28-d trial, 6 pigs from each treatment were randomly selected to collect serum and intestinal samples. On d 14 after the initiation of the trial, pigs in the SDPP, SDPP + SDCP, and SDCP groups had an increase ( < 0.05) in serum concentrations of total protein and IgG and a decrease ( < 0.05) in activities of alanine aminotransferase and diamine oxidase compared with the CON group. In the jejunum, supplementation with SDPP and SDCP reduced ( < 0.05) the concentration of tumor necrosis factor-α (TNF-α) and upregulated ( < 0.05) the mRNA levels of zonula occludens 1 (ZO-1), zonula occludens 2 (ZO-2), occludin (OCLN), Toll-like receptor 2 (TLR2), glucagon-like peptide 2 (GLP2), and IGF-1 compared with the CON group. In the ileum, feeding SDPP, SDPP + SDCP, and SDCP decreased ( < 0.05) the concentrations of TNF-α and secretory IgA (sIgA) and upregulated ( < 0.05) the mRNA levels of claudin 1 (CLDN-1) and TLR2 compared with feeding CON. However, there were no differences among the SDPP, SDPP + SDCP, and SDCP groups. Furthermore, supplementation with SDCP reduced ( < 0.05) the concentration of IL-10 and upregulated ( < 0.05) the mRNA levels of GLP-2, mucin 2 (MUC2), and trefoil factor family 3 (TFF3) in the ileum compared with feeding CON. Collectively, the current results indicate that dietary addition of SDCP has a beneficial influence on the health condition of weaning pigs by alleviating liver damage, promoting intestinal development, improving intestinal barrier function, and reducing overstimulation of immune response. The efficacy of SDCP is comparable to that of SDPP.

One hundred forty-four 25-d-old weaning piglets with BW of 6.43 ± 0.39 kg were used in a 28-d trail to evaluate the effects of dietary addition of spray-dried chicken plasma (SDCP) as a replacement for spray-dried porcine plasma (SDPP) on growth performance, nutrient digestibility, diarrhea incidence, small intestinal morphology, digestive enzyme activity, and microflora. Pigs were randomly allotted to 1 of 4 dietary treatments: 1) CON (control; a basal diet), 2) SDPP (containing 5% SDPP), 3) SDPP + SDCP (containing 2.5% SDPP and 2.5% SDCP), and 4) SDCP (containing 5% SDCP). Six pigs from each treatment were randomly selected to collect serum and intestinal samples. Compared with the CON group, both the SDPP and the SDPP + SDCP groups improved final BW of pigs (P < 0.05), but there were no differences among the SDPP, SDPP + SDCP, and SDCP groups. From d 1 to 14 and d 15 to 28, pigs fed the SDPP and SDPP + SDCP diets had a greater (P < 0.05) ADG than pigs fed the CON diet. During the overall period, both ADG and ADFI of pigs in the SDPP and SDPP + SDCP groups were improved (P < 0.05) compared with pigs in the CON group. Furthermore, pigs fed diets containing SDPP or SDCP had a greater (P < 0.05) apparent total tract digestibility (ATTD) of CP, ether extract, Ca, and ash and less (P < 0.05) incidence of diarrhea than pigs fed the CON diet. However, no differences were observed for ATTD and diarrhea incidence between the SDPP and SDCP groups. Compared with the CON group, duodenal villus height and the ratio of villi to crypt were increased (P < 0.05) in the SDPP, SDPP + SDCP, and SDCP groups and jejunal crypt depth was decreased in the SDPP + SDCP and SDCP groups (P < 0.05). Pigs in the SDPP group had greater (P < 0.05) activities of amylase, maltase, and trypsin than pigs in the CON group. However, no significant differences were observed between the SDCP and SDPP groups. Additionally, inclusion of SDCP in diet decreased (P < 0.05) the population of Escherichia coli. In conclusion, these results demonstrated that the addition of SDCP in pigs’ diet had an effect similar to SDPP on improving growth performance through the promotion of the small intestinal development, increasing digestive enzymes activities, enhancing ATTD of nutrients, and decreasing diarrhea incidence.