Dietary short-term supplementation of grape seed proanthocyanidin extract improves pork quality and promotes skeletal muscle fiber type conversion in finishing pigs

Plant extracts are commonly used as feed additives to improve pork quality. However, due to their high cost, shortening the duration of supplement use can help reduce production costs. In this study, we aimed to investigate the effects of grape seed proanthocyanidin extract (GSPE) on meat quality and muscle fiber characteristics of finishing pigs during the late stage of fattening, which was 30 days in our experimental design. The results indicated that short-term dietary supplementation of GSPE significantly reduced backfat thickness, but increased loin eye area and improved meat color and tenderness. Moreover, GSPE increased slow myosin heavy chain (MyHC) expression and malate dehydrogenase (MDH) activity, while decreasing fast MyHC expression and lactate dehydrogenase (LDH) activity in the Longissimus thoracis (LT) muscle. Additionally, GSPE increased the expression of Sirt1 and PGC-1α proteins in the LT muscle of finishing pigs and upregulated AMP-activated protein kinase α 1 (AMPKα1), AMPKα2, nuclear respiratory factor 1 (NRF1), and calcium/calmodulin-dependent protein kinase kinase β (CaMKKβ) mRNA expression levels. These findings suggest that even during the late stage of fattening, GSPE treatment can regulate skeletal muscle fiber type transformation through the AMPK signaling pathway, thereby affecting the muscle quality of finishing pigs. Therefore, by incorporating GSPE into the diet of pigs during the late stage of fattening, producers can enhance pork quality while reducing production costs.

The effects of synbiotics-glyconutrients on growth performance, nutrient digestibility, gas emission, meat quality, and fatty acid profile of finishing pigs

Glyconutrients help in the body's cell communication. Glyconutrients and synbiotics are promising options for improving immune function. Therefore, we hypothesized that combining synbiotics and glyconutrients will enhance pig nutrient utilization. 150 pigs (Landrace × Yorkshire × Duroc), initially weighing 58.85 ± 3.30 kg of live body weight (BW) were utilized to determine the effects of synbiotics-glyconutrients (SGN) on the pigs' performance, feed efficiency, gas emission, pork traits, and composition of fatty acids. The pigs were matched by BW and sex and chosen at random to 1 of 3 diet treatments: control = Basal diet; TRT1 = Basal diet + SGN 0.15%; TRT2 = Basal diet + SGN 0.30%%. The trials were conducted in two phases (weeks 1-5 and weeks 5-10). The average daily gain was increased in pigs fed a basal diet with SGN (p = 0.036) in weeks 5-10. However, the apparent total tract digestibility of dry matter, nitrogen, and gross energy did not differ among the treatments (p > 0.05). Dietary treatments had no effect on NH3, H2S, methyl mercaptans, acetic acids, and CO2 emissions (p > 0.05). Improvement in drip loss on day 7 (p = 0.053) and tendency in the cooking loss were observed (p = 0.070) in a group fed basal diets and SGN at 0.30% inclusion level. The group supplemented with 0.30% of SGN had higher levels of palmitoleic acid (C16:1), margaric acid (C17:0), omega-3 fatty acid, omega-6 fatty acid, and ω-6: ω-3 ratio (p = 0.034, 0.020, 0.025, 0.007, and 0.003, respectively) in the fat of finishing pigs. Furthermore, group supplemented with 0.30% of SGN improved margaric acid (C17:0), linoleic acid (C18:2n6c), arachidic acid (C20:0), omega 6 fatty acid, omega-6 to omega-3 ratio, unsaturated fatty acid, and monounsaturated fatty acid (p = 0.037, 0.05, 0.0142, 0.036, 0.033, 0.020, and 0.045, respectively) in the lean tissues of finishing pigs compared to pigs fed with the control diets. In conclusion, the combination of probiotics, prebiotics, and glyconutrients led to higher average daily gain, improved the quality of pork, and more favorable fatty acid composition. Therefore, these results contributed to a better understanding of the potential of SGN combinations as a feed additive for pigs.

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.

Alfalfa leaf meal as a new protein feedstuff improves meat quality by modulating lipid metabolism and antioxidant capacity of finishing pigs

The effects of alfalfa leaf meal (ALM) on the meat quality of finishing pigs are largely unknown. Here, we investigated the effects of ALM diet on meat quality by replacing 0%, 25%, 50%, and 75% of soybean meal in the diet of finishing pigs, respectively. The findings showed that 25% ALM diet increased the IMF, cooked meat rate, a* and antioxidant capacity of longissimus dorsi (LD), improved amino acid composition, increased MUFA content, and increased LD lipid synthesis and mRNA expression of antioxidation-related genes. At the same time, ALM diet altered serum lipid metabolism (TG, FFA). Correlation analysis showed that antioxidant capacity was positively correlated with meat quality. In addition, metabolomic analysis of LD showed that the main metabolites of 25% ALM diet altered stachydrine and l-carnitine were associated with meat quality and antioxidant capacity. In conclusion, ALM replacing 25% soybean meal diet can improve the meat quality of pigs.

Carcass and meat quality traits and their relationships in Duroc × Landrace × Yorkshire barrows slaughtered at various seasons

To understand characteristics of carcass traits and meat quality in pig population, 22 indicators of carcass characteristics and meat quality traits were measured on 278 Duroc × Landrace × Yorkshire barrows that were slaughtered in different seasons (spring, summer, autumn and winter). The effects of body weight and season on carcass characteristics and meat quality were analyzed by GLM procedure, followed the Bonferroni multiple test. The phenotypic correlations among those traits were calculated by employing the CORR procedure. In addition, the linear regression equations were constructed by stepwise regression model in REG procedure. The results showed that pigs slaughtered in spring had the heaviest body weight among the four seasons (P < 0.05), pigs slaughtered in summer had the lowest backfat depth and shear force (P < 0.05), and pigs slaughtered in winter had the lowest drip loss (P < 0.05). The results showed more variation in backfat depth, drip loss, intramuscular fat content, and shear force, compared with other indicators across pigs. Body weight had a significant association with loin eye area, average backfat depth and L^⁎_{24 h} (P < 0.05). Furthermore, regression equations for drip loss, cooking loss, shear force, and intramuscular fat content were constructed using more accessible indicators. Collectively, this study provided an overall view of carcass and meat quality traits in a commercial pig population in China, and illustrated that season significantly affected carcass characteristics and meat quality traits independently of body weight.

Effects of dietary grape seed proanthocyanidin extract supplementation on meat quality, muscle fiber characteristics and antioxidant capacity of finishing pigs

The aim of this study was to investigate effects of dietary grape seed proanthocyanidin extract (GSPE) supplementation on meat quality, muscle fiber characteristics and antioxidant capacity of finishing pigs. The data showed GSPE increased pH24 h, redness, crude protein content and decreased shear force, drip loss48 h, lactate content and glycolytic potential in longissimus dorsi (LD) muscle, accompanied by increased contents of total polyunsaturated fatty acid (PUFA), n-3 PUFA, and the ratio of PUFA to saturated fatty acid. GSPE promoted MyHC I mRNA and slow MyHC protein expression, and increased slow-twitch fiber percentage. The activities of total antioxidant capacity, total superoxide dismutase, catalase and glutathione peroxidase in LD muscle were increased by GSPE while malondialdehyde content was decreased. Together, this study demonstrated that dietary GSPE supplementation can effectively improve the color, water-holding capacity, tenderness and nutritional value of pork, and increase slow-twitch fiber percentage and antioxidant capacity of finishing pigs.

Different dietary starch sources alter the carcass traits, meat quality, and the profile of muscle amino acid and fatty acid in finishing pigs

BACKGROUND

With increasing health awareness among consumers, the demand for healthier, tastier, higher quality and nutritional value pork is increasing. It has been shown that different dietary starch sources can alter the carcass traits and meat quality. However, research on the effects of different starch sources with clear different amylose/amylopectin ratio on the amino acid and fatty acid composition in Longissimus thoracis (L. thoracis) muscle of pigs is limited. This study aimed to investigate the effects of different dietary starch sources on carcass traits, meat quality, muscle amino acid and fatty acid composition, and the mRNA expression levels of genes involved in lipid metabolism and muscle fiber characteristics in finishing pigs. A total of 72 Duroc × Landrace × Large White barrows were randomly allocated to 3 different dietary treatment groups with 8 replicate pens/group and 3 pigs per pen. Tapioca starch (TS), corn starch (CS), and pea starch (PS), with amylose/amylopectin ratio of 0.11, 0.25, and 0.44, respectively, were used as their dietary starch sources for 40 days.

RESULTS

Results showed that the PS diet significantly increased (P < 0.05) the final body weight, average daily gain, loin-eye area, and fat-free lean index compared with the TS diet, but significantly decreased (P < 0.05) the feed to gain ratio and backfat thickness. Compared with the TS diet, PS diet also increased (P < 0.05) the pH45 min, marbling scores, the content of intramuscular fat and inosine monophosphate in the L. thoracis, and decreased (P < 0.05) the drip loss and shear force. In addition, compared with the TS diet, PS diet increased (P < 0.05) the proportions of flavor amino acids, DHA, EPA, and n-3 polyunsaturated fatty acid (PUFA) in the L. thoracis compared with TS diet, but decreased (P < 0.05) the ratio of n-6/n-3 PUFA. Furthermore, compared with the TS diet, PS diet also upregulated (P < 0.05) the lipogenic genes (FAS, LPL, SCD, ACCα) and myosin heavy-chain (MyHC)-IIa mRNA expression levels compared with the TS diet, but downregulated (P < 0.05) the CPT1B and MyHC-IIb mRNA levels.

CONCLUSIONS

In conclusion, these results provided compelling evidence that the different dietary starch source altered the carcass traits, meat flavor and quality in finishing pigs, and consumption of a diet with higher amylose/amylopectin ratio results in the production of a healthy, higher quality, and nutritional value pork.

Increasing selenium supplementation to a moderately-reduced energy and protein diet improves antioxidant status and meat quality without affecting growth performance in finishing pigs

BACKGROUND

Along with economic development and living standards' improvement, more and more attention has been converted from satisfying meat quantity to pursuing meat quality.

RESEARCH PURPOSE

This study was conducted to evaluate the effects of increasing selenium (Se) supplementation to a moderately-reduced energy and protein diet (MREP) on growth performance, antioxidant status, meat quality in finishing pigs.

BASIC PROCEDURES

A total of 144 "Duroc × Landrace × Yorkshire" pigs with the average body weight of 75 ± 1 kg were randomly allotted to 3 dietary treatments with six replicates per treatment and eight pigs per replicate. The 3 experimental diets were as follows: (1) Normal energy and protein (NEP) +0.2 mg/kg Se diet (14.02 MJ/kg DE, 14% CP and 0.2 mg/kg Se as selenite sodium), (2) MREP +0.2 mg/kg Se diet (13.60 MJ/kg DE, 13% CP and 0.2 mg/kg Se as selenite sodium), and (3) MREP +0.5 mg/kg Se diet (13.60 MJ/kg DE, 13% CP, 0.2 mg/kg Se as selenite sodium, and 0.3 mg/kg Se as Se-enriched yeast). The study lasted for 45 days.

MAIN FINDINGS

The results show that there were no differences for growth performance, antioxidant status and meat quality of finishing pigs between NEP +0.2 mg/kg Se group and MREP +0.2 mg/kg Se group (P＞0.05). However, compared to pigs from MREP +0.2 mg/kg Se group, pigs from MREP +0.5 mg/kg Se group had greater Se concentration, GSH-Px activity and GSH concentration, but lower MDA concentration in serum (P＜0.05). Also, pigs from MREP +0.5 mg/kg Se group had greater Se concentration, T-AOC, and SOD activity, but lower MDA concentration in loin compared with pigs from MREP +0.2 mg/kg Se group (P＜0.05). As for meat quality, pigs from MREP +0.5 mg/kg Se group had greater a* value (relative redness) at 45 min and 24 h in loin compared with pigs from MREP +0.2 mg/kg Se group (P＜0.05). Compared to pigs from MREP +0.2 mg/kg Se group, pigs from MREP +0.5 mg/kg Se group had lower MDA concentration of fresh pork during a simulated retail display at 0, 1, 2, 4, 6 and 7 day (P＜0.05).

PRINCIPAL CONCLUSIONS

In conclusion, increasing selenium supplementation to a moderately-reduced energy and protein diet improved antioxidant status and meat quality without affecting growth performance in finishing pigs. (New Aspects) The present study provided a nutritional strategy for reducing feed costs and improving pork quality without influencing growth performance in finishing pigs.

The effect of dietary garcinol supplementation on oxidative stability, muscle postmortem glycolysis and meat quality in pigs

The objective of this study was to evaluate the effects of dietary garcinol (0, 200, 400 and 600 mg/kg) on the growth performance, meat quality, postmortem glycolysis and antioxidative capacity of finishing pigs. Dietary garcinol increased pigs' average daily gain, pH _24h, a* and myoglobin content of longissimus dorsi (LM) (P < 0.05), and decreased feed/gain ratio, the L*_24h, glycolytic potential, drip loss, shear force, and backfat depth (P < 0.05). The glutathione peroxidase (GPx), catalase (CAT) and total antioxidative capacity (T-AOC) were significantly increased by garcinol (P < 0.05), while the activity of lactate dehydrogenase (LDH) and malonaldehyde (MDA) content were decreased (P < 0.05). Moreover, garcinol decreased the p300/CBP-associated factor (PCAF) activity, the acetylation level and activities of glycolysis enzymes phosphoglycerate kinase 1 (PGK1), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and 6-phosphofructo-2-kinase/fructose-2, 6-bisphosphatase-3 (PFKFB3) (P < 0.05). The results of this study showed that garcinol decreased postmortem glycolysis, and this may be due to the mechanism of decreasing glycolytic enzyme acetylation induced by PCAF. The present study indicates that garcinol can facilitate the growth performance of pigs and improve pork quality by changing postmortem glycolysis and antioxidative capacity.

Dietary β-glucan supplementation improves growth performance, carcass traits and meat quality of finishing pigs

This experiment was conducted to investigate growth performance, carcass traits and meat quality of finishing pigs with dietary β-glucan supplementation. A total of 96 healthy pigs (Duroc × Landrace × Yorkshire; initial average BW = 25 kg) were randomly allocated into 4 dietary treatments with 6 replicates per treatment and 4 pigs per replicate. The control group was fed a basal diet, and the experimental diets were supplemented with 50, 100 and 200 mg/kg Agrobacterium sp. ZX09 β-glucan, respectively. The experiment lasted 103 d. The basal diet supplemented with 100 mg/kg β-glucan significantly increased average daily gain and feed conversion ratio, probably due to the improved digestibility of dry matter, gross energy and crude protein (P < 0.05). Beta-glucan supplementation from 100 to 200 mg/kg of diet significantly increased carcass length (P < 0.05). The basal diet supplemented with 100 mg/kg β-glucan supplementation also significantly (P < 0.05) increased muscle pH, reduced drip losses and increased a^∗ values. The basal diet supplemented with 100 mg/kg β-glucan increased the content of intramuscular fat and changed the proportion of saturated fatty acid and unsaturated fatty acid, thereby improved the flavor of meat. In conclusion, the basal diet supplemented with 100 mg/kg Agrobacterium sp. ZX09 β-glucan improves growth performance, nutrient digestibility, carcass length, and pork quality of finishing pigs.

Hermetia illucens larvae as a potential dietary protein source altered the microbiota and modulated mucosal immune status in the colon of finishing pigs

Background

Insects, such as Hermetia illucens larvae, are rich in chitin and proteins, and represent a suitable feed ingredient replacement for animals. However, little is known about the effect of administering H. illucens larvae on intestinal microbiota, bacterial metabolite profiles, and mucosal immune status in animals. This study aimed to investigate the effects of administering H. illucens larvae on colonic microbiota and bacterial metabolites production in finishing pigs. Seventy-two crossbred (Duroc × Landrace × Large White) female pigs (initial body weight, 76.0 ± 0.52 kg) were randomly allocated to three different dietary treatments: a control diet (Control group) and two diets corresponding to 4% (H1 group) and 8% (H2 group) H. illucens larvae inclusion levels, respectively. Each treatment consisted of eight pens (replicates), with three pigs per pen. After 46 days of feeding, eight pigs per treatment (n = 8) were slaughtered, and the colonic digesta and mucosa were collected for microbial composition and microbial fermentation products, and genes expression analyses.

Results

The results showed that the H1 diet significantly increased the abundance of Lactobacillus, Pseudobutyrivibrio, Roseburia, and Faecalibacterium compared with those in the control group (P < 0.05), with a decrease in the abundance of Streptococcus. The numbers of Lactobacillus, Roseburia, and Clostridium cluster XIVa were significantly greater in the H1 group than in the control group (P < 0.05). Meanwhile, H2 diet increased the number of Clostridium cluster XIVa compared with the control group (P < 0.05). For colonic metabolites, total short chain fatty acids, butyrate, and isobutyrate concentrations were significantly higher in the H1 group than those in the control group (P < 0.05); the H1 treatment caused a striking decrease in protein fermentation compared with the control group, as the concentrations of total amines, cadaverine, tryptamine, phenol, p-cresol, and skatole were significantly lower (P < 0.05). Additionally, H2 diet also increased butyrate concentration compared with control group (P < 0.05), while decreased the concentrations of phenol, p-cresol, and skatole (P < 0.05). Pigs in the H1 group down-regulated the expression of TLR-4 and pro-inflammatory cytokines (IFN-γ) compared with pigs in the control group (P < 0.05), and up-regulated anti-inflammatory cytokine (IL-10) and intestinal barrier genes (ZO-1, occludin, and mucin-1). H2 diet up-regulated the expression of ZO-1 compared with control group (P < 0.05). Furthermore, the changes in the colonic mucosal gene expression were associated with changes in the bacterial composition and their metabolites.

Conclusions

Collectively, dietary inclusion of Hermetia illucens larvae may enhance mucosal immune homeostasis of pigs via altering bacterial composition and their metabolites. These findings provide a new perspective on insect meal as a sustainable protein source rich in nutrient ingredients for swine.

Electronic supplementary material

The online version of this article (10.1186/s40104-019-0358-1) contains supplementary material, which is available to authorized users.

Use of Hermetia illucens larvae as a dietary protein source: Effects on growth performance, carcass traits, and meat quality in finishing pigs

This study investigated the effects of feeding Hermetia illucens larvae (0, 4, and 8%; HI0, HI4, and HI8 groups, respectively) on growth performance, carcass traits, and meat quality of finishing pigs. Results showed that the HI4 diet increased (P < .05) final body weight and average daily gain and decreased (P < .05) feed to gain ratio compared with HI0 and HI8 group. HI4 and HI8 diets increased (P < .05) loin-eye area, marbling scores, and inosine monophosphate content of longissimus thoracis (LT) compared with HI0 diet. The intramuscular fat content was greater (P < .05) in HI4 group than in the HI0 group. Furthermore, HI4 diet up-regulated (P < .05) lipogenic genes and MyHC-IIa mRNA levels in LT compared with HI0 diet. Our results indicated that dietary inclusion of H. illucens larvae has a beneficial impact on growth performance and meat quality, and the underlying mechanism may be due to the altered lipogenic potential induced by H. illucens larvae.

Supplementation of different fat sources affects growth performance and carcass composition of finishing pigs

Background

There are various fat sources with different energy values and fatty acid compositions that may affect growth performance and carcass composition of grow-finishing pigs. A higher net energy was recently reported in choice white grease compared with soybean oil. Therefore, two experiments were conducted to determine whether practical responses confirm that difference between choice white grease and soybean oil, and to extend the observations to other fat sources.

Results

In Exp. 1, pigs fed fats had lower (P < 0.05) average daily feed intake in phase II and overall period, greater (P < 0.05) gain:feed in phase I, phase II, and overall period than pigs fed the control diet. Pigs fed fats tended (P = 0.057) to have thicker backfat depth at the last rib than those fed control. Pigs fed 6% fats had greater (P < 0.01) gain:feed in phase II and overall period than pigs fed 3% fats. During phase I, pigs fed choice white grease grew faster (P < 0.05) than pigs fed soybean oil. In Exp. 2, pigs fed dietary fats (soybean oil, choice white grease, animal-vegetable blend, palm oil, or tallow) had greater (P < 0.01) gain:feed in each phase and overall period, greater (P < 0.01) average daily gain in phase I, but lower (P < 0.01) average daily feed intake in phase II an overall than pigs fed the control diets. The choice white grease also increased (P < 0.05) average daily gain during phase I compared with soybean oil. Pigs fed palm oil had thicker (P < 0.05) backfat depth at the 10^th rib than those fed soybean oil, animal-vegetable blend, or tallow.

Conclusions

Inclusion of 6% dietary fat improved feed efficiency of finishing pigs, while different fats produced different practical results that may be consistent with their different energy values. Results from the early stage indicate that dietary fats with relatively more saturated fatty acids may provide greater energy than those with relatively more unsaturated fatty acids for growing pigs.

Prevalence, bioserotyping and antibiotic resistance of pathogenic Yersinia enterocolitica detected in pigs at slaughter in Sardinia

The aims of the present study were to determine Yersinia enterocolitica prevalence in finishing pigs and piglets at slaughter and to characterize the isolates in terms of bioserotype, virulence profile, antimicrobial susceptibility and genetic diversity. During the years 2013-2014, nine pig slaughterhouses placed in Sardinia (Italy) were visited twice, in order to collect animal samples and scalding water. Overall, 609 samples respectively of tonsils (126), colon content (161), mesenteric lymph nodes (161) and carcass surfaces (161) were collected from 126 finishing pigs and 35 piglets. Moreover, 18 scalding water samples were collected. Samples were analyzed for the detection of Y. enterocolitica according to ISO 10273-2003 standard (with some modifications). With regard to finishing pigs, Y. enterocolitica was detected in 11.9% of colon content samples, 3.2% of tonsils and 2.4% of lymph nodes. In piglets, Y. enterocolitica prevalence was 8.6% in colon content and 2.8% lymph nodes samples. Y. enterocolitica was not detected from carcass surface samples of both finishing pigs and piglets and from scalding water samples. Isolates were bio- and serotyped, tested for the presence of four virulence genes by PCR (ail, ystA, ystB and inv) and for antimicrobial resistance by disc-diffusion method. Among 47 confirmed isolates, 33 (70.2%) belonged to bio-serotype 4:O3, 7 (14.9%) to bio-serotype 2/O:5 and 7 (14.9%) to bio-serotype 1A. Bio-serotype 1A was detected only in isolates of piglets' samples. In bio-serotype 4/O:3 isolates the most common virulence genes were ystA (97.0%), ail (84.8%) and inv (78.8%). In bio-serotype 2/O:5, ail, inv and ystA genes were detected in all of the isolates. All bio-serotype 1A isolates were ystB positive (lacking ail, inv and ystA). All isolates were susceptible to cefotaxime, ceftazidime, chloramphenicol, ciprofloxacin, enrofloxacin, gentamicin, nalidixic acid, sulphonamide, tetracycline and trimethoprim-sulphametoxazole. Resistances to ampicillin and cefalothin were the most common (100%), followed by amoxicillin/clavulanic acid (83.0%) and streptomycin (4.3%). Resistance to amoxicillin/clavulanic acid was detected in 57% of bio-serotype 4/O:3 isolates, 71% of bio-serotype 1A and 100% of bio-serotype 2/O:5 isolates. Two bio-serotype 4/O:3 isolates (6%) were resistant to streptomycin. Thirty-two pathogenic Y. enterocolitica isolates were tested by NotI-PFGE, which identified 5 patterns among bio-serotype 4/O:3 isolates and 2 patterns among bio-serotype 2/O:5 isolates. This study provides epidemiological data about human pathogenic Y. enterocolitica and highlight the role of pigs as a potential source of infection for the consumers in Sardinia.

Effects of dietary starch types on early postmortem muscle energy metabolism in finishing pigs

This study aimed to investigate the effects of different dietary starch types on early postmortem muscle energy metabolism in finishing pigs. Ninety barrows (68.0±2.0kg) were randomly allotted to three experimental diets with five replicates of six pigs, containing pure waxy maize starch (WMS), nonwaxy maize starch (NMS), and pea starch (PS) (amylose/amylopectin were 0.07, 0.19 and 0.28 respectively). Compared with the WMS diet, pigs fed the PS diet exhibited greater creatine kinase activity, higher adenosine triphosphate and adenosine diphosphate contents, lower phosphocreatine (PCr), adenosine monophosphate and glycogen contents, and lower glycolytic potential (P<0.05). Moreover, the PS diet led to reduced percentage of bound hexokinase activity, decreased level of phosphorylated AKT (P<0.05) and increased level of hypoxia-inducible factor-1α (P<0.05). In conclusion, diet with high amylose content might promote PCr degradation and inhibit the rate of glycolysis, followed by attenuation of early postmortem glycolysis in finishing pigs.

Dietary starch types affect liver nutrient metabolism of finishing pigs

This study aimed to evaluate the effect of different starch types on liver nutrient metabolism of finishing pigs. In all ninety barrows were randomly allocated to three diets with five replicates of six pigs, containing purified waxy maize starch (WMS), non-waxy maize starch (NMS) and pea starch (PS) (the amylose to amylopectin ratios were 0·07, 0·19 and 0·28, respectively). After 28 d of treatments, two per pen (close to the average body weight of the pen) were weighed individually, slaughtered and liver samples were collected. Compared with the WMS diet, the PS diet decreased the activities of glycogen phosphorylase, phosphoenolpyruvate carboxykinase and the expression of phosphoenolpyruvate carboxykinase 1 in liver (P0·05). Compared with the WMS diet, the PS diet reduced the expressions of glutamate dehydrogenase and carbamoyl phosphate synthetase 1 in liver (P<0·05). PS diet decreased the expression of the insulin receptor, and increased the expressions of mammalian target of rapamycin complex 1 and ribosomal protein S6 kinase β-1 in liver compared with the WMS diet (P<0·05). These findings indicated that the diet with higher amylose content could down-regulate gluconeogenesis, and cause less fat deposition and more protein deposition by affecting the insulin/PI3K/protein kinase B signalling pathway in liver of finishing pigs.

Effects of dietary starch types on growth performance, meat quality and myofibre type of finishing pigs

To investigate the effects of dietary starch types on growth performance and meat quality of finishing pigs, ninety barrows (68.0±2.0kg) were randomly allotted to three experimental diets with five replicates of six pigs, containing pure waxy maize starch (WMS), nonwaxy maize starch (NMS) and pea starch (PS) (amylose/amylopectin were 0.07, 0.19 and 0.28 respectively). Compared with WMS diet, PS diet increased the average daily gain, loin eye area, pH45 value, NMR transverse relaxation (T2)2 peak area ratio and sarcoplasmic protein solubility, decreased the feed to gain ratio, back fat, drip loss, cooking loss and T23 peak area ratio (P<0.05). Moreover, PS diet increased the myosin heavy-chain (MyHC)-I and IIa levels, decreased the MyHC-IIb level, decreased the miR23a level and increased its target gene level, increased the miR499 level and decreased its target gene level (P<0.05). Diet with high amylose content might be beneficial to the growth performance and meat quality of finishing pigs.

Effect of dietary supplementation with sugar cane extract on meat quality and oxidative stability in finishing pigs

The aim of the present study was to investigate the effect of dietary supplementation with sugar cane extract (SCE) on meat quality and oxidative stability of Longissimus dorsi muscle in finishing pigs. Eighteen barrows (Duroc × Landrace × Jiaxing Black), with an average initial body weight of 62.1 ± 5.0 kg, were randomly allotted to 1 of 3 diets with 6 replicates per treatment for 42 days. The diets comprised a normal diet and the normal diets supplemented with 5 and 25 g/kg SCE. The results showed that SCE supplementation did not affect final body weight of finishing pigs. Dietary SCE supplementation significantly increased (P < 0.05) Longissimus dorsi muscle pH24 h, and tended to reduce (P < 0.1) and significantly decreased (P < 0.05) shear force, drip loss, myofiber cross sectional area and lactate dehydrogenase activity at 5 and 25 g/kg, respectively. Meanwhile, dietary SCE treatments significantly decreased (P < 0.05) malonaldehyde content and total superoxide dismutase activity in Longissimus dorsi muscle, and tended to reduce (P < 0.1) malonaldehyde content in serum. Altogether, these data indicate that SCE is an effective feed additive to improve pork meat quality, and the underlying mechanism may be partly due to the improved oxidative stability induced by dietary SCE supplementation.

Effects of the ratio of unsaturated fatty acid to saturated fatty acid on the growth performance, carcass and meat quality of finishing pigs

The effects on finishing pigs (80–100 kg BW) fed diets supplemented with oil sources containing different ratios of unsaturated to saturated fatty acids (UFA:SFA ratio) were evaluated in 15 barrows and 15 gilts (Duroc × Large White × Landrace). Three experimental diets were evaluated using a randomized complete block design, with broken rice, soybean meal and rice bran as the main feedstuffs in the control diet. Diets 2 and 3 consisted of the control diet supplemented with 3% oil, with UFA:SFA ratios of 2.5:1 and 5:1, respectively. Overall, there was no significant difference (P > 0.05) found in the average daily gain (ADG) of the pigs fed the treatment diets; however, the pigs fed the control diet and diet 3 had better (P < 0.05) feed conversion ratios (FCR) than the pigs fed diet 2. The pigs fed diets 2 and 3, which were supplemented with oil at UFA:SFA ratios of 2.5:1 and 5:1, had greater (P < 0.05) average daily feed intakes (ADFI) than the pigs in the control group. Additionally, it was found that the gender of the pigs had an effect (P < 0.05) on the FCR. Interaction effects between the experimental diets and the gender of the pigs (P < 0.05) were found in the ADFI and FCR. There were no significance differences (P > 0.05) among the treatment groups with regard to the carcass quality of the pigs; however, it was found that the gilts had greater (P < 0.01) loin eye areas than the barrows fed diets 2 and 3 and the loin eye area of pig fed diet 2 was the largest (P < 0.05). In the case of the meat quality parameters, it was clearly found that the pigs fed the control diet had a greater (P < 0.05) lightness (L^∗) in the meat colour, and the lowest cooking loss was found in the pigs fed the diet supplemented with fat containing the UFA:SFA ratio of 5:1. Overall, the dietary treatment did not significantly affect the drip loss, thawing loss and shear force of the pork. In conclusion, the supplementation of oil with UFA:SFA ratios of 2.5:1 and 5:1 has the potential to improve pork quality.

Nutritionally related blood metabolites and performance of finishing pigs fed on graded levels of dietary fibre

The objective of the study was to determine effect of feeding fibrous diets on performance and biochemical profiles of finishing pigs. A total of 84 clinically healthy male pigs were used in the experiment. Body weight of the pigs at the beginning of the experiment was 85 ± 10.1 kg. Maize cob (MC), sunflower hulls (SH), lucerne hay (LH) and dried citrus pulp (PU) were incorporated in a basal diet for finishing pigs at different inclusion levels of 0, 80, 160, 240, 320 and 400 g/kg. Effects of week of feeding, fibre source and inclusion level of fibre were significant (P < 0.05). Pigs consumed more LH compared to MC, SH and PU. Average daily gain was high for pigs consuming diets with inclusion levels of 0, 80, 160 and 240 g/kg and low for pigs consuming 320 and 400 g/kg inclusion level of fibre in a diet. There was an increase in serum total concentration (TP) with an increase in PU, MC and LH in pig diets (P < 0.05). Creatine kinase (CK) concentrations decreased as levels of PU, LH and MC increased (P < 0.05). Increasing inclusion level of LH and SH in pig diets resulted in an increase in glycated haemoglobin concentration (P < 0.05). It can be concluded that level of PU, LH, MC and SH in diets of finishing pigs negatively influences average daily feed intake, average daily gain and biochemical profiles.

Impact of particulate matter and ammonia on average daily weight gain, mortality and lung lesions in pigs

The present study investigated the simultaneous influence of particulate matter (PM10) and ammonia (NH3) on performance, lung lesions and the presence of Mycoplasma hyopneumoniae (M. hyopneumoniae) in finishing pigs. A pig herd experiencing clinical problems of M. hyopneumoniae infections was selected. In total, 1095 finishing pigs of two replicates in eight compartments each were investigated during the entire finishing period (FP). Indoor PM10 and NH3 were measured at regular intervals during the FP with two Grimm spectrometers and two Graywolf Particle Counters (PM10) and an Innova photoacoustic gas monitor (NH3). Average daily weight gain (ADG) and mortality were calculated and associated with PM10 and NH3 during the FP. Nasal swabs (10 pigs/compartment) were collected one week prior to slaughter to detect DNA of M. hyopneumoniae with nested PCR (nPCR). The prevalence and extent of pneumonia lesions, and prevalence of fissures and pleurisy were examined at slaughter (29 weeks). The results from the nasal swabs and lung lesions were associated with PM10 and NH3 during the FP and the second half of the FP. In the univariable model, increasing PM10 concentrations resulted in a higher odds of pneumonia lesions (second half of the FP: OR=8.72; P=0.015), more severe pneumonia lesions (FP: P=0.04, second half of the FP: P=0.009), a higher odds of pleurisy lesions (FP: OR=20.91; P<0.001 and second half of the FP: OR=40.85; P<0.001) and a higher number of nPCR positive nasal samples (FP: OR=328.00; P=0.01 and second half of the FP: OR=185.49; P=0.02). Increasing NH3 concentrations in the univariable model resulted in a higher odds of pleurisy lesions (FP: OR=21.54; P=0.003) and a higher number of nPCR positive nasal samples (FP: OR=70.39; P=0.049; second half of the FP: OR=8275.05; P=0.01). In the multivariable model, an increasing PM10 concentration resulted in a higher odds of pleurisy lesions (FP: OR=8.85; P=0.049). These findings indicate that the respiratory health of finishing pigs was significantly affected by PM10.

Effects of dietary n-6:n-3 PUFA ratio on fatty acid composition, free amino acid profile and gene expression of transporters in finishing pigs

Revealing the expression patterns of fatty acid and amino acid transporters as affected by dietary n-6:n-3 PUFA ratio would be useful for further clarifying the importance of the balance between n-6 and n-3 PUFA. A total of ninety-six finishing pigs were fed one of four diets with the ratio of 1:1, 2·5:1, 5:1 and 10:1. Pigs fed the dietary n-6:n-3 PUFA ratio of 5:1 had the highest (P< 0·05) daily weight gain, and those fed the dietary n-6:n-3 PUFA ratio of 1:1 had the largest loin muscle area (P< 0·01). The concentration of n-3 PUFA was raised as the ratio declined (P< 0·05) in the longissimus dorsi and subcutaneous adipose tissue. The contents of tryptophan, tasty amino acids and branched-chain amino acids in the longissimus dorsi were enhanced in pigs fed the dietary n-6:n-3 PUFA ratios of 1:1-5:1. The mRNA expression level of the fatty acid transporter fatty acid transport protein-1 (FATP-1) was declined (P< 0·05) in the longissimus dorsi of pigs fed the dietary n-6:n-3 PUFA ratios of 1:1-5:1, and increased (P< 0·05) in the subcutaneous adipose tissue of pigs fed the dietary n-6:n-3 PUFA ratios of 5:1 and 10:1. The expression profile of FATP-4 was similar to those of FATP-1 in the adipose tissue. The mRNA expression level of the amino acid transceptors LAT1 and SNAT2 was up-regulated (P< 0·05) in the longissimus dorsi of pigs fed the dietary n-6:n-3 PUFA ratios of 1:1 and 2·5:1. In conclusion, maintaining the dietary n-6:n-3 PUFA ratios of 1:1-5:1 would facilitate the absorption and utilisation of fatty acids and free amino acids, and result in improved muscle and adipose composition.

Welfare measurements of finishing pigs on the day of slaughter: a review

Animal welfare on the day of slaughter is of increasing concern to the authorities and consumers alike, creating a need not only to optimize the welfare of the animals but also to document the level of welfare. The day of slaughter is composed of a variety of stages, initiated when the pigs leave the home pen and including pick-up facilities, transport, lairage, stunning and sticking. At each of these stages, the animals are exposed to different stressors that, both individually and in interaction with one another, can compromise welfare. As part of the initial work aiming to document the welfare of finishing pigs on the day of slaughter, this paper provides an overview of the individual stages including a discussion of potential stressors and potential welfare measurements. These measurements are discussed with regard to their relevance and suitability for documentation of animal welfare on the day of slaughter for development of on-site tools for continuous automatic monitoring of animal welfare.

Salmonella Enterica Prevalence in Finishing Pigs at Slaughter Plants in Northern Italy

Finishing pigs carrying Salmonella enterica are believed to be the main source of carcass contamination at the beginning of slaughtering. The aim of this study was to assess the S. enterica carrier status of finishing pigs at herd level by sampling pooled faeces on farm and mesenteric lymph nodes at slaughter in the North East of Italy. Environmental faecal samples belonging to 30 batches of pigs were collected on farm. At slaughter, mesenteric lymph nodes were collected from five randomly selected pigs per batch. S. enterica was isolated from 16 lymph nodes out of 150 (10.6%) and from seven out of 30 (23.3%) faecal samples. Four batches (13.3%) were positive to S. enterica both in lymph nodes and in faeces. The number of batches positive to S. enterica either in lymph nodes or in faeces was 13 out of 30 (43.3%). The most prevalent serovars from lymph nodes were S. Derby (25.0%) and S. Typhimurium monophasic variant 1, 4,[5],12:i:- (18.6%), which were also isolated from faecal material (14.3 and 42.8% respectively). Contaminated faecal material or lymph nodes could be a primary source of carcass contamination at slaughter during evisceration. S. enterica contamination is widespread on pig farms and carrier pigs pass undetected the inspection visits at slaughter, entering the food chain. Therefore, in order to control S. enterica in pigs, the need to quantify possible risk factors at slaughter and develop effective management strategies on farm is of paramount importance to ensure food safety.