Effect of dietary organic selenium on muscle proteolytic activity and water-holding capacity in pork

Effects of Se-enriched yeast on the amelioration of atrazine-induced meat quality degradation

Atrazine (ATR) is herbicide that causes serious harm to the environment and threatens human food safety. Se-enriched yeast is the best organic selenium source for protecting cells from damage caused by poisonous substances. To explore mechanism of ATR on meat quality degradation and potential protective effects of Se-enriched yeast on ATR-induced muscle injury, quails were treated with ATR and/or Se-enriched yeast for 28 days. The results found ATR disrupted muscle fiber structure and decreased pH, tenderness, water-holding capacity, essential amino acid content and polyunsaturated fatty acid content. ATR aggravated oxidative stress and inflammation by inhibiting Nrf2 pathway and activating NF-κB pathway, ultimately causing apoptosis. However, Se-enriched yeast alleviated ATR-induced alterations in muscle chemical and physical properties by inhibiting oxidative stress and inflammation. Taken together, these results revealed that ATR exposure caused meat quality degradation and Se-enriched yeast had the potential to counteract ATR-induced myotoxicity by inhibiting oxidative stress and inflammation.

Exploring effects of organic selenium supplementation on pork loin: Se content, meat quality, antioxidant capacity, and metabolomic profiling during storage

This research was conducted to study the effects of organic selenium (Se) supplements at different levels on pork loin quality during storage. Fifteen pork loins were procured randomly from three groups, Con (fed basal diet), Se15 (fed 0.15 ppm organic Se along with 0.10 ppm inorganic Se), and Se45 (fed 0.45 ppm organic Se along with 0.10 ppm inorganic Se). Each sample was analyzed for Se contents, antioxidant properties (glutathione peroxidase [GPx] activity, 2,2'-azinobis-[3-ethylbenzothiazoline-6-sulfonic acid] [ABTS] and 2,2-diphenyl-1-picrylhydrazyl [DPPH] radical scavenging activities, 2-thiobarbituric acid reactive substances), physicochemical properties (water holding capacity, pH, color), and metabolomic analysis during 14-day storage period. Se45-supplemented group showed significantly higher Se contents and GPx activity than the other groups throughout the storage period. However, other antioxidant properties were not significantly affected by Se supplementation. Selenium supplementation did not have an adverse impact on physicochemical properties. Nuclear Magnetic Resonance-based metabolomic analysis indicated that the selenium supply conditions were insufficient to induce metabolic change. These results suggest that organic Se (0.15 and 0.45 ppm) can accumulate high Se content in pork loins without compromising quality.

Dietary Protected Sodium Butyrate and/or Olive Leaf and Grape-Based By-Product Supplementation Modifies Productive Performance, Antioxidant Status and Meat Quality in Broilers

To meet the demand for chicken meat production, new additives that promote growth and health without adverse effects on meat quality are being investigated. This study was conducted to investigate the effect of protected sodium butyrate (PSB) (0 vs. 2 g/kg), an olive leaf and grape-based by-product (OLG-mix), or a combined supplementation of PSB and OLG-mix on productive performance, antioxidant status, carcass, and meat quality in broilers. PSB improved performance parameters with greater effect in the initial phase. Both, PSB and OLG-mix increased the plasma superoxide dismutase (SOD); however, PSB supplementation was more effective to delay the lipid oxidation of meat from the initial day of storage. OLG-mix produced meat with greater color intensity, b* value and lesser drip losses than PSB. The combination of PSB + OLG-mix did not produce more marked effects that the individual administration; except to control the oxidation of meat. Linear and positive correlations between antioxidant enzymes and weight gain were observed. Significant linear and negative relationships were quantified between plasma SOD and meat lipid oxidation according to dietary treatment. Therefore, the present study would be a first approximation to the possibilities for predicting growth range and meat quality through the evaluation of the blood oxidative status.

SNP discovery and association study for growth, fatness and meat quality traits in Iberian crossbred pigs

Iberian pigs and its crosses are produced to obtain high-quality meat products. The objective of this work was to evaluate a wide panel of DNA markers, selected by biological and functional criteria, for association with traits related to muscle growth, fatness, meat quality and metabolism. We used 18 crossbred Iberian pigs with divergent postnatal growth patterns for whole genome sequencing and SNP discovery, with over 13 million variants being detected. We selected 1023 missense SNPs located on annotated genes and showing different allele frequencies between pigs with makerdly different growth patterns. We complemented this panel with 192 candidate SNPs obtained from literature mining and from muscle RNAseq data. The selected markers were genotyped in 480 Iberian × Duroc pigs from a commercial population, in which phenotypes were obtained, and an association study was performed for the 1005 successfully genotyped SNPs showing segregation. The results confirmed the effects of several known SNPs in candidate genes (such as LEPR, ACACA, FTO, LIPE or SCD on fatness, growth and fatty acid composition) and also disclosed interesting effects of new SNPs in less known genes such as LRIG3, DENND1B, SOWAHB, EPHX1 or NFE2L2 affecting body weight, average daily gain and adiposity at different ages, or KRT10, NLE1, KCNH2 or AHNAK affecting fatness and FA composition. The results provide a valuable basis for future implementation of marker-assisted selection strategies in swine and contribute to a better understanding of the genetic architecture of relevant traits.

Effects of Selenium Auricularia cornea Culture Supplementation on Growth Performance, Antioxidant Status, Tissue Selenium Concentration and Meat Quality in Growing-Finishing Pigs

Simple Summary

Selenium Auricularia cornea culture (SAC) is a dried product via full fermentation, containing organic-Se, Auricularia cornea (AC) mycelium, and various metabolites of AC. The objective of this study was to evaluate whether SAC could effectively improve the health, growth, meat quality, and oxidative stability of meat in growing-finishing pigs. Currently, dietary SAC supplementation positively impacts growth performance and oxidative stability of fresh meat.

Abstract

Selenium Auricularia cornea culture (SAC) is a new source of organic selenium. Two experiments were conducted to determine the available energy of SAC fed to pigs and to evaluate the effects of dietary SAC supplementation on growth performance, serum biochemical profiles, fecal short chain fatty acids (SCFA), meat quality, tissue selenium concentration, and oxidative stability of fresh meat in growing-finishing pigs. In Experiment (Exp.) 1, 12 barrows with average body weight (BW) of 42.40 ± 5.30 kg were randomly allotted to two groups and fed the basal diet and SAC-supplemented diet, individually. In Exp. 2, 96 growing-finishing pigs (BW: 91.96 ± 7.55 kg) were grouped into four dietary treatments; each treatment contained six replicates with four pigs per replicate. The four treatments fed a control diet and three experimental diets supplemented with 0.6%, 1.2%, and 2.4% SAC, respectively. The trial lasted for 45 days. The results revealed that digestible energy (DE) of SAC was 11.21 MJ/kg. The average daily gain (ADG) was improved in pigs fed 1.2% and 2.4% SAC during day 24 to 45 and the overall period. Dietary 1.2% and 2.4% SAC supplementation had a lower F/G (p < 0.05) than the control diet during different stages. Dietary SAC supplementation increased fecal butyrate contents (p < 0.05), and pigs fed 1.2% and 2.4% SAC diets had a higher MCT1 mRNA expression (p = 0.04) in the colon. Pigs fed 2.4% SAC had higher GSH-Px contents (p < 0.05) in serum, liver, and longissimus dorsi muscle (LDM) than those in the control group. The 2.4% SAC-supplemented group revealed a higher Se content (p < 0.05) in LDM and a lower MDA concentration (p < 0.05) in fresh meat during the simulated retail display on day six. In conclusion, this study suggested that SAC was more effective in improving growth, enhancing the antioxidant status, depositing Se in muscle, and increasing meat oxidative stability of pigs.

Selenium and Natural Zeolite Clinoptilolite Supplementation Increases Antioxidative Status and Immune Response in Growing Pigs

Selenium (Se), an essential trace element for human and animal health, is covalently incorporated into amino acids, acts as a cofactor for antioxidant enzymes, and is involved in the maintenance of the immune system. The main goal of this investigation was to show the effect of Se supplementation, at levels slightly higher than the recommended values, combined with natural zeolite clinoptilolite on Se deposition in tissues (muscle and liver) and on the immune and antioxidative status of supplemented growing pigs. The experiment was carried out during a 98 d period on 60 pigs. Pigs were fed a standard feed mixture based on corn and soybean and were divided into four groups, according to the level of dietary selenium supplementation as follows: C-0.3 mg/kg DM organic Se, E1-0.5 mg/kg DM sodium selenite, E2-0.5 mg/kg DM organic selenium; E3-0.5 mg/kg DM organic Se+0.2% zeolite. Higher (P < 0.05) selenium concentrations were determined in the muscle and liver in growing pigs fed with higher organic Se in combination with zeolite compared to the lower organic Se concentration. Addition of organic Se increased (P < 0.05) Se deposition in muscle and liver compared to the equal amount of inorganic Se (E2 vs. E1). Higher organic Se in combination with natural zeolite addition increases (P < 0.05) proportion of pigs' cluster of differentiation (CD)45⁺ compared to the same amount of inorganic Se and lower organic Se addition. The proportion of CD45⁺ and CD4⁺ lymphocytes was higher (P < 0.05) in E3 group compared to the other groups. Higher (P < 0.05) proportion of CD21⁺ lymphocytes were measured in the E2 and E3 groups compared with the other groups. The highest (P < 0.01) activity of glutathione peroxidase (GSH-Px) in pig erythrocytes was observed in the E3 group, while higher (P < 0.05) activity of glutathione reductase (GR) was in all experimental groups related to the control one. A dietary addition of 0.5 mg/kg DM of organic Se in combination with zeolite (0.2% DM) has increased (P < 0.05) Se deposition in liver, muscle, and blood, compared to the dietary addition of 0.3 mg/kg DM of the organic Se.

Dietary oleuropein extract supplementation and its combination with α-tocopheryl acetate and selenium modifies the free fatty acid profile of pork and improves its stability

BACKGROUND

Olive-derived antioxidants have been shown to affect the oxidative status of meat and have also been associated with greater consumption of glucose, which might affect glycogen stores and muscle characteristics. This study evaluated the effect of oleuropein extract supplementation (OLE) versus vitamin E + Se (VE), and their combination (VEOLE), in pig diets, on pH, drip loss, the proportion of free fatty acids, and meat stability, and their prediction by blood oxidative status markers.

RESULTS

The drip loss of muscle was lower in antioxidant-supplemented groups when compared with controls. α-Tocopherol concentration and total fatty acids profile were not affected by dietary oleuropein supplementation. However, OLE and VEOLE had lower free n-3 polyunsaturated fatty acid (PUFA) levels when compared with VE and tended to have higher free monounsaturated fatty acid (MUFA) levels. Furthermore, the VEOLE group had lower free n-6 PUFA levels when compared with controls or VE, whereas the OLE group had intermediated values. Muscle samples from pigs subjected to the antioxidant-mixed supplementation (VEOLE) had lower malondialdehyde concentration when compared with the others. The VE and OLE groups showed intermediate malondialdehyde values. Chilled meat stability was highly correlated with antioxidant status in vivo.

CONCLUSION

The administration of 96 mg oleuropein kg^-1 feed produced similar meat quality characteristics as the use of 100 mg kg^-1 α-tocopheryl acetate +0.26 mg kg^-1 sodium selenite and it would be an interesting alternative in Mediterranean countries. The VEOLE group was the most effective for reducing lipid oxidation and for the production of polyunsaturated free fatty acids in meat, which would result in lower rancidity formation and better aroma development in products. © 2020 Society of Chemical Industry.

Effects of L-Glutamine Supplementation during the Gestation of Gilts and Sows on the Offspring Development in a Traditional Swine Breed

Simple Summary

Nutritional strategies during pregnancy in swine production are considered essential to increase the number of piglets born alive and improve their survival and development. Amino acids, such as glutamine, are among the best compound to introduce in commercial farms after obtaining positive results in trials carried out in selected swine breeds. However, several critical productive factors have to be assessed before translating these strategies to the farm level to ensure the best balance between benefits and investments. The current study focused on the effects of prenatal L-glutamine supplementation on the offspring of Iberian gilts and sows under farm conditions. It is the first trial of amino acid supplementation during pregnancy carried out in traditional swine breeds. These non-selected swine breeds show productive or physiological differences that could affect the supplementation effect. Indeed, although there were changes at the molecular and tissue level, these effects did not turn into advantageous effects for the offspring of traditional breeds. The present study shows the importance of pre-testing nutritional strategies under the final conditions and breeds of implementation and the need to deepen at the molecular level to improve the biological interpretation of findings.

Abstract

The use of amino acids during pregnancy, such as glutamine (Gln), seems to be a promising strategy in selected swine breeds to improve the offspring prenatal development. The main goal of the current study was to assess the development of the offspring from parity 1–3 sows of a traditional breed, which were supplemented with 1% glutamine after Day 35 of gestation, under farm conditions. A total of 486 (288 treated) piglets from 78 (46 treated) Iberian sows were used. At birth and slaughterhouse, fatty acid composition, metabolism, and mTOR pathway gene expression were analyzed. At birth, treated newborns showed greater amounts of specific amino acids in plasma, such as glutamine, asparagine, or alanine, and Σn-3 fatty acids in cellular membranes than control newborns. The expression of genes belonging to mTOR Complex 1 was also higher in treated piglets with normal birth-weight. However, these findings did not improve productive traits at birth or following periods in litters from supplemented gilts (parity 1) or sows (parities 2–3). Thus, further research is needed to properly understand the effects of prenatal glutamine supplementation, particularly in traditional swine breeds.

Supplementation Effect of Oleuropein Extract Combined with Betaine, Magnesium, and Vitamin E on Pigs' Performance and Meat Quality Characteristics

Simple Summary

Oleuropein, betaine, magnesium, and vitamin E show antioxidant and/or metabolic effects on the organism that are reflected, in many cases, in performances and meat quality. This study evaluated whether the combination of these nutrients at two doses manifest different effects on the final product. Both combinations were enough to improve the oxidative status of pigs, although performances were not affected. However, the higher doses increased n-6 and n-3 PUFA in the triglycerides and free fatty acid fractions that resulted in meat that was more susceptible to oxidation.

Abstract

This study evaluates the effect of the dietary combination of oleuropein extract (1200 mg/kg) and betaine (1000 mg/kg), magnesium oxide (600 mg/kg), and α–tocopheryl acetate (400 mg/kg), or a half-dose of these compounds, on pigs’ performance, oxidative status, and meat quality characteristics (drip loss, TBARS, and texture and fatty acid profile of intramuscular fat). Sixty-six barrows and females were slaughtered at 120 kg of BW. Performance and carcass yield were not changed by treatments. The high-dose mixture resulted in higher serum ferric reducing/antioxidant power (p = 0.0026), lower glucose (p = 0.03) and a tendency to have lower serum TBARS (p = 0.07) when compared to control. Percentage of drip loss, moisture content, intramuscular fat, or texture parameters were not modified by dietary treatments. Pigs supplemented with the high-dose mixture had higher PUFA (p = 0.0001), n-6 (p = 0.0001), n-3 (p = 0.0095) and lower MUFA (p = 0.0064) in the neutral lipid fraction of intramuscular fat. Free PUFA, mainly n-3 fatty acids (p = 0.0009), were also higher in the meat of pigs fed the high-dose mixture compared with the others. A higher mobilization (neutral to free fatty acids hydrolysis) of n-3 and MUFA fatty acids in the muscle from pigs fed the high-dose mixture was observed. However, dietary mixture supplementation tended to increase MUFA (p = 0.056) and decrease the total PUFA (p = 0.0074) proportions in muscle polar lipids. This specific fatty acid composition of meat from pigs supplemented with the high-dose mixture could be responsible for the higher meat lipid oxidation observed in this group when compared to the other groups. Consequently, the low-dose mixture would be more adequate for maintaining the oxidative status of pigs and, meat lipid stability.

Effect of Castor and Cashew Nut Shell Oils, Selenium and Vitamin E as Antioxidants on the Health and Meat Stability of Lambs Fed a High-Concentrate Diet

Functional oils are known for their compounds with antioxidant, antimicrobial and anti-inflammatory properties, and are used in ruminant nutrition as alternatives to chemicals in order to improve performance. This study aimed to compare the influence of castor and cashew nut shell oils with pure organic selenium (hydroxy-selenomethionine) plus vitamin E, which are known and well-stablished antioxidants, on the performance traits, shelf life and microbial quality of the meat, physiological functions and oxidative stress control of lambs. Thirty-two Dorper x Santa Ines lambs (initial bodyweight of 22.42 ± 3.9 kg and 60 days of age) were submitted to a diet consisting of Cynodon dactylon hay (6%) and concentrate (94%). The animals were divided into four treatments: control, without additives; functional oils (FO), 0.50 g/kg DM of castor and cashew nut shell oils; hydroxy-selenomethionine and vitamin E (SeE), 0.50 mg/kg of organic selenium and 100 IU/kg DM of vitamin E; FO plus SeE, at the same doses as the other groups. Blood samples were collected after 1, 30 and 53 days on feed. After 54 days, the lambs were slaughtered and rumen health, carcass and meat traits, shelf life, and microbiological quality were evaluated. There were no differences in performance or carcass traits. A higher muscle and serum Se concentration (p < 0.0001), lower lipid peroxidation in meat during display (p < 0.0001), and a lower count of psychrotrophic microorganisms on day 5 were observed in the SeE and FO plus SeE groups. The treatments reduced the counts of Enterobacteriaceae, and Staphylococcus spp. FO animals showed higher GSH-Px activity on day 30, while the peroxidase activity was higher in FO plus SeE animals (p = 0.035). SeE and FO plus SeE animals had lower serum ALT and AST levels. Functional oils improved the microbiological quality of meat. Hydroxy-selenomethionine and vitamin E prevented oxidative stress, lipid peroxidation, and microbial spoilage.

Effect of modelled stress and adaptogens on microstructural characteristics of pork from fast-growing hybrid animals

This research aimed to study the effect of modelled technological stress and the introduction of selenium and dihydroquercetin (DHQ) into pig diets on the microstructure of M. longissimus dorsi muscle tissue. The in vivo experiment was carried out on 36 hybrid young barrows (Large White x Landrace) x Duroc) with an initial live weight of 34 – 36 kg until they reached a weight of not less than 110 kg. The animals were divided into four groups: 1 (C-) – pigs did not receive adaptogens and were not subjected to modelled technological stress; 2 (C+) – pigs did not receive adaptogens but were subjected to stress via relocation of animals; 3 (С+Se) – pigs were subjected to stress and received 0.2 mg Se.kg-1 feed as selenium proteinate in addition to their diet; 4 (С+DHQ) – pigs were subjected to stress and received 32 mg DHQ.kg-1 feed in addition to their diet. The best results regarding the muscle tissue condition were recorded in the musle  L. dorsi samples were taken from the carcasses of group 4 (С+DHQ). Analysis of variance using the Fisher–Snedecor test confirmed that addition of adaptogens led to an improvement of the pH24 value (at p = 0.05, f observed  = 5.90 >fcritical = 4.17) and moisture-holding capacity (at p = 0.05, f observed  = 3.04 >fcritical = 2.92). The effect of long-term addition of DHQ to pig diets (78 days) on the condition of muscle tissue was studied for the first time, which allowed us to conclude its role in the prevention of myopathic changes in the muscle fibre structure.

Effect of Different Selenium Sources on Growth Performance, Tissue Selenium Content, Meat Quality, and Selenoprotein Gene Expression in Finishing Pigs

Se-methylselenocysteine (MeSeCys) is a natural organic selenium (Se) supplement. However, its effects on animal nutrition are poorly understood. This study compared the effects of sodium selenite (SeNa), MeSeCys, and selenomethionine (SeMet) on immune function, tissue Se concentration, meat quality, and selenoprotein gene expression in pigs. A total of 72 finishing pigs were divided into four groups, which received a basal diet (BD, 0.1 mg Se/kg) without Se supplementation or one supplemented with SeNa, MeSeCys, or SeMet at a concentration of 0.25 mg Se/kg. Organic Se supplementation significantly increased the immune globulin A (IgA), IgG, and IgM serum levels compared with BD and SeNa groups (P < 0.05). There were no statistically significant differences in growth performance among the four groups. SeMet was more efficient in increasing Se concentrations in the heart, muscle, and liver than MeSeCys and SeNa (P < 0.05), while no statistically significant differences were observed between MeSeCys and SeNa. Se supplementation significantly decreased the pressing muscle loss compared with the BD group (P < 0.05). Meat color and pH were not significantly affected. Se supplement effects on liver selenoprotein gene mRNA level enhancement were ranked as follows: MeSeCys > SeMet > SeNa (P < 0.05). In muscle tissues, only the SELENOW mRNA level was significantly increased by the MeSeCys and SeMet treatment, compared with the SeNa group. In conclusion, SeMet was more efficient in increasing Se concentrations than MeSeCys and SeNa in pigs, while MeSeCys was more efficient in enhancing selenoprotein gene expression than SeMet and SeNa.

Vitamin D3 Supplementation in Drinking Water Prior to Slaughter Improves Oxidative Status, Physiological Stress, and Quality of Pork

The aims of this study were to investigate the effect of vitamin D₃ administration in drinking water during lairage time prior to slaughter on physiological stress, oxidative status, and pork quality characteristics. Two experiments were carried out. The first one was performed to examine the effect of vitamin D₃ supplementation in drinking water, and the second one to check the effect of supplementation dose (500,000 IU/L vs. 700,000 IU/L). Serum calcium concentration was greater in pigs receiving vitamin D₃ in water when compared to the control group. In experiment 1, a 40% α-tocopherol increase in meat from the group supplemented with vitamin D₃ (500,000 IU/animal) was observed, that resulted in a tendency of decreased meat malondialdehyde (MDA) values at days 5 and 8 after refrigerated storage. In experiment 2, since water intake was higher (800,000 IU and 1,120,000 IU/animal of vitamin D₃ consumption) effects on oxidative status were more profound and vitamin D₃ supplementation increased serum α-tocopherol and decreased cortisol and serum TBARS. These effects were also observed in meat; TBARS levels were decreased after 3 days of refrigerated storage. In both experiments meat from pigs that received vitamin D₃ in drinking water had a lower proportion of total free-polyunsaturated fatty acids (mainly n-6) when compared to the unsupplemented pigs, and these were positively correlated with TBARS production at day 5 of refrigerated storage (r = 0.53 and 0.38 for experiments 1 and 2, respectively). Meat from pigs receiving vitamin D₃ in water showed reduced cohesiveness, gumminess, and chewiness values compared to the control group. The magnetic resonance imaging study of muscle confirmed the effects on water retention with lesser transverse relaxation time in pigs supplemented with vitamin D₃. No vitamin D₃ dose effect was observed, apart from muscle α-tocopherol concentration that was higher in pigs supplemented with 700,000 compared to those supplemented with 500,000 UI/L.

Piglet birthweight and sex affect growth performance and fatty acid composition in fatty pigs

This study aimed to determine the effects of piglet birthweight (BIW) and sex, and within-litter BIW variation, on postnatal growth traits and meat quality in fatty breeds of pig. In total, 406 crossbred piglets (half male, half female) born to Iberian sows were studied during their postnatal development until slaughter. After birth, piglets were classified into four BIW categories: very low, low, medium and high. There was a negative effect of low BIW on growth patterns and fatty acid (FA) composition, but effects of litter size and within-litter BIW variation were not found. The very low BIW piglets underwent a period of significant catch-up growth (P &lt; 0.005) relative to high BIW piglets during the early postnatal phase, but also showed a higher feed conversion rate and lower average daily weight gain (P &lt; 0.05 for both measures) throughout the study period. BIW affected development during the entire productive life, and the sex effect increased with age. As a result, the period to reach market weight was longer in very low BIW piglets, by 43 days for females and 15 days for males, compared with their high BIW counterparts. BIW and sex also influenced amount of intramuscular fat, n-3 FA content and monounsaturated FA composition. The study indicates that BIW, modulated by sex, is a critical point for productive traits in fatty pigs. These results provide a basis for future strategies to enhance productive efficiency and meat quality of traditional swine breeds.

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.

Magnolol additive improves carcass and meat quality of Linwu ducks by modulating antioxidative status

Magnolol rich in Magnolia officinalis is a bioactive polyphenolic compound. The aim of this study was to clarify the effects of magnolol additive (MA) on carcass and meat quality, biochemical characteristics and antioxidative capacity of Linwu ducks, by comparing it to that of antibiotic additive (colistin sulphate, CS). A total of 275 49-d-old ducks were randomly assigned to 5 groups with 5 cages of 11 ducks each and fed by the diets supplemented with 0, 100, 200 and 300 mg of MA/kg and 30 mg of CS/kg for 3 weeks, respectively. The results revealed that MA administration not only increased dressed percentage (calculated as a percentage of live weight), percentage of breast muscle, leg muscle and lean meat (calculated as a percentage of eviscerated weight), but also remarkably increased a*_{45 min} and pH_{45 min} of leg muscle. Moreover, MA administration decreased the percentage of abdominal fat (calculated as a percentage of eviscerated weight), 45-min cooking loss, water loss rate of leg muscle, 45-min cooking loss and drip loss of breast muscle at 24 hr and 48 hr. Furthermore, MA administration enhanced the activities of superoxide dismutase and catalase in serum or liver, serum total antioxidant capacity and hepatic reduced glutathione concentration significantly, compared with the basal diet or CS group (p < .05). On the other hand, triglyceride, total cholesterol, aspartate aminotransferase, malondialdehyde, protein carbonyl and 8-hydroxy-2'-deoxyguanosine contents in serum and liver were significantly increased in Linwu ducks fed with CS, compared with MA groups (p < .05). Taken together, these data demonstrated that magnolol could effectively improve the carcass and meat quality of Linwu ducks by regulating the in vivo antioxidant status and would be a potential candidate to replace antibiotic.

Polyphenols and IUGR Pregnancies: Effects of Maternal Hydroxytyrosol Supplementation on Postnatal Growth, Metabolism and Body Composition of the Offspring

Maternal supplementation with the polyphenol hydroxytyrosol in a swine model of intrauterine growth restriction (IUGR) improves the fetal oxidative status, decreases the appearance of low birth-weight neonates and favors growth during early postnatal stages (lactation). The current study aimed to determine whether hydroxytyrosol supplementation can also improve developmental patterns, metabolic traits, and body composition of the offspring during later postnatal stages (from weaning to adulthood). A total of 21 piglets born from control untreated sows and 20 piglets born from sows treated with hydroxytyrosol during the last two-thirds of pregnancy were selected on the basis of similar body weights at weaning, for avoiding any interfering effects occurred during lactation. The pigs in the treated group had higher average daily weight gain (ADWG) and, therefore, reached higher body weight and corpulence, greater muscle development and higher adiposity than their control counterparts. The following were not found: significant effects on metabolism and body composition except changes in the muscular fatty acid composition of the treated pigs coming from the largest litters; those more affected by IUGR processes. These findings suggest that maternal supplementation with hydroxytyrosol may improve juvenile development of offspring in at-risk pregnancies and pave the way for more specific studies aiming to elucidate effects on adiposity, metabolism, and meat organoleptic characteristics.

Efeito da suplementação de suínos em terminação com diferentes associações entre minerais sobre o desempenho, as características de carcaça e a viabilidade econômica

RESUMO Objetivou-se, com este estudo, verificar a influência da suplementação com diferentes associações entre minerais orgânicos sobre o desempenho e as características de carcaça, bem como avaliar sua viabilidade econômica, para suínos em terminação. Foram utilizados 88 machos castrados, divididos entre quatro tratamentos: controle com dieta basal e suplementação com CrFe, MgSe e CrFeMgSe, durante os 28 dias que antecederam o abate. O delineamento experimental foi em blocos ao acaso, com parcela experimental representada por dois animais. Os animais suplementados com CrFeMgSe apresentaram piores índices de peso final, ganho de peso diário e consumo durante todo o período, com consequente redução no peso de carcaça, menor profundidade de lombo, área de olho-de-lombo e menor quantidade de carne magra na carcaça. Houve um aumento no custo da dieta para os grupos CrFe, MgSe e CrFeMgSe, respectivamente. O uso de cromo mais ferro e magnésio mais selênio, associados dois a dois, não altera os parâmetros de desempenho e as características de carcaça. A associação dos quatro minerais, no entanto, promove piora nessas características e aumenta o custo da dieta.

Current feeding strategies to improve pork intramuscular fat content and its nutritional quality

Pork, one of the most consumed meats worldwide, has been facing major challenges regarding its low sensory quality and unhealthy image of fat. This chapter addresses current feeding strategies to ameliorate pork sensory attributes and nutritional quality by increasing intramuscular fat deposition and improving fatty acid composition, respectively. Dietary protein reduction, alone or combined with some components, contributes to satisfy consumer requirements and enhances the competitiveness of the meat industry with higher pork quality and lower production costs. In addition, feeding sources of n-3 polyunsaturated fatty acids to pigs, mainly from marine origin (rich in eicosapentaenoic and docosahexaenoic acids), increases their content in pork, thus improving the health value of its fatty acid profile. In the near future, the inclusion of microalgae and seaweeds in feed represents a promising approach for the maintenance and development of the livestock sector, as an environmental friendly alternative to balance food and feed industries.

Soybean isoflavones improve the health benefits, flavour quality indicators and physical properties of grass carp (Ctenopharygodon idella)

Health benefits, flavour quality indicators and physical properties were analysed after feeding grass carp graded concentrations of soybean isoflavones (SIF) (0, 25, 50, 75, 100 and 125 mg/kg) for 60 days. The results demonstrated that optimal dietary SIF supplementation improved the protein and total PUFA content, especially healthcare n-3 PUFA (C18: 3n-3, EPA and DHA), and increased the flavour-related free amino acid [especially umami amino acid] and 5'-inosine monophosphate content, improving the health benefits and flavour quality indicators in the muscle of grass carp. In addition, optimal dietary SIF supplementation (25 or 50 mg SIF/kg diet) enhanced some physical properties [water-holding capacity and tenderness] and increased the collagen content; however, it reduced cathepsin activity and apoptosis. SIF supplementation enhanced the glutathione content and the activity of antioxidant enzymes (except CuZnSOD) by regulating their gene expression. The gene expression could be regulated by NF-E2-related factor 2 (Nrf2) signalling in the muscle of grass carp. We demonstrated that optimal dietary SIF supplementation elevated the health benefits, flavour quality indicators and physical properties of fish muscle.

Maternal undernutrition and offspring sex determine birth-weight, postnatal development and meat characteristics in traditional swine breeds

Background

The aim of this study was to determine how maternal undernutrition during pregnancy and offspring birth-weight can affect the postnatal development of offspring under farm conditions, which may lead to consequences in its meat and carcass quality. The current study involved a total of 80 litters from Iberian sows fed a diet fulfilling daily requirements (n = 47; control) or providing 70% daily requirements (n = 33; underfed) from d 38 to d 90 of gestation when fetal tissue development begins. After birth, piglets born live were classified as low birth-weight (LBW; < 1 kg) and normal birth-weight (NBW; ≥1 kg). During the growing phase, 240 control and 230 underfed pigs (50% males and females) distributed by BW category and sex were studied until the slaughter.

Results

At birth and weaning, there were significant differences in all morphological measures and weight between NBW and LBW piglets as expected (P < 0.0005), but few effects of the gestational feed restriction. During the growing phase, NBW pigs continued with higher weight than LBW pigs on all the days of evaluation (P < 0.05), even though control-LBW-females and LBW-males showed a catch-up growth. However, underfed pigs showed slower growth and higher feed conversion ratio than control pigs (P < 0.0001) at 215 days old. Moreover, the average daily weight gain (ADWG) for the overall period was greater for NBW, male and control pigs than for their LBW, female and underfed pigs (P < 0.0001, P< 0.0005 and P< 0.05, respectively) and NBW pigs were slaughtered at a younger age than LBW pigs (P < 0.0001). After slaughtering, control pigs also had higher carcass yield and backfat depth than underfed pigs (P < 0.0005) and the maternal nutritional effect caused main changes in the polar lipid fraction of liver and loin. The fatty acid composition of loin in control pigs had higher C18:1n-9 and n-3 FA concentrations, as well as lower ∑n-6/∑n-3 ratio, than in underfed pigs (P < 0.005).

Conclusions

In brief, results showed that the effects of maternal nutritional restriction appeared and increased with offspring age, causing worse developmental patterns for underfed pigs than for control pigs.

Electronic supplementary material

The online version of this article (10.1186/s40104-018-0240-6) contains supplementary material, which is available to authorized users.

Analyzing μ-Calpain induced proteolysis in a myofibril model system with vibrational and fluorescence spectroscopy

Degree of post-mortem proteolysis influences overall meat quality (e.g. tenderness and water holding capacity). Degradation of isolated pork myofibril proteins by μ-Calpain for 0, 15 or 45 min was analyzed using four spectroscopic techniques; Raman, Fourier transform infrared (FT-IR), near infrared (NIR) and fluorescence spectroscopy. Sodium dodecyl sulfate polyacrylamide gel electrophoresis was used to determine degree of proteolysis. The main changes detected by FT-IR and Raman spectroscopy were degradation of protein backbones manifested in the spectra as an increase in terminal carboxylic acid vibrations, a decrease in CN vibration, as well as an increase in skeletal vibrations. A reduction in β-sheet secondary structures was also detected, while α-helix secondary structure seemed to stay relatively unchanged. NIR and fluorescence were not suited to analyze degree of proteolysis in this model system.

Meat quality, free fatty acid concentration, and oxidative stability of pork from animals fed diets containing different sources of selenium

This study evaluates the effect of the source of dietary selenium supplementation (organic versus mineral) and the combined effect of organic selenium and vitamin E on the fatty acid composition and lipolysis in pork intramuscular fat and other meat quality characteristics such as drip loss and lipid stability. Higher vitamin E deposition, lower drip loss, and higher stability against oxidation were detected in muscle from pigs fed organic selenium. Also higher proportion of free fatty acids was observed in intramuscular fat from pigs fed organic selenium than those fed inorganic selenium, being these mainly coming from neutral lipid fraction. In addition, the inclusion of vitamin E in the diet enhanced such effect. Dietary organic selenium also increased Δ9-desaturase and elongase indexes and C18:1n−9 concentration. A related decrease of C18:0 concentration was also observed. Described differences in the lipid fraction composition could affect sensory characteristics of meat and meat products.