Meat Oxidative Stability Research Articles

Effects of Co-Supplementation of β-Galacto-Oligosaccharides and Methionine on Breast Meat Quality, Meat Oxidative Stability, and Selected Meat Quality Genes in Broilers

Effects of Co-Supplementation of β-Galacto-Oligosaccharides and Methionine on Breast Meat Quality, Meat Oxidative Stability, and Selected Meat Quality Genes in Broilers

In Vitro Antioxidant Activities of Plant Polyphenol Extracts and Their Combined Effect with Flaxseed on Raw and Cooked Breast Muscle Fatty Acid Content, Lipid Health Indices and Oxidative Stability in Slow-Growing Sasso Chickens.

Adding flaxseed was found to decrease oxidative stability in feed and increase the antioxidant needs of chicken. This has also been associated with a decrease in the nutritional value and oxidative stability of meat if sufficient dietary antioxidants are not included. Furthermore, dietary flaxseed has been explored in fast-growing chickens as such studies are limited with slow-growing chickens. Thus, this study aimed to evaluate the effects of feeding plant polyphenol extracts as an antioxidant alongside flaxseed on fatty acid content, oxidative stability, and lipid health indices in breast muscle of slow-growing Sasso T451A dual-purpose chicken. A total of 126 chickens assigned to six groups (seven replicates of three) were fed on NC (control and no antioxidants), FS (75 g flaxseed and no antioxidants), VE8 (75 g flaxseed and 800 mg vitamin E), TS8 (75 g flaxseed and 800 mg Thymus schimperi), DA8 (75 g flaxseed and 800 mg Dodonaea angustifolia) and CD8 (75 g flaxseed and 800 mg Curcuma domestica) extract per kg diet. Feeding on CD8 and VE8 in raw and TS8, CD8 and VE8 diets in cooked breast muscle increased (p < 0.05) the C22:6n − 3 (DHA) and C20:5n − 3 (EPA) contents compared to the FS diet. Feeding FS increased (p < 0.05) the malondialdehyde (MDA) content in breast muscle, whereas TS8 in cooked and raw and CD8 and DA8 diets in raw breast muscle decreased it (p < 0.05). No added benefit was observed in feeding VE8 over plant extracts in terms of improving fatty acid composition and lipid health indices and reducing lipid oxidation in breast meat.

Broiler meat fatty acids composition, lipid metabolism, and oxidative stability parameters as affected by cranberry leaves and walnut meal supplemented diets

A randomized complete block with a 2 × 3 factorial arrangement was used to design a nutrition experiment conducted for the evaluation of the relation between walnut meal (WM—6% inclusion rate) and cranberry leaves (CL—1% and 2% inclusion rate) supplements and their effects on tissue lipid profile, lipid metabolism indices and oxidative stability of meat. Semi-intensive system conditions were simulated for 240 Ross 308 broilers and the animals were reared on permanent shave litter in boxes of 3 m2 (40 broilers / each group, housed in a single box). The current study results showed that the diets enriched in linolenic acid (LNA) (WM diets) led to broilers meat enriched in LNA, but the synthesis of long-chain omega-3 polyunsaturated fatty acids (LC n-3 PUFA) was stimulated when the diets were supplemented with a natural antioxidants source (CL diets). The CL diet also exhibited the most powerful effect in counteracting the oxidative processes of meat.

Studies on antioxidant activities of grape pomace using in vitro, ex vivo, and in vivo models

Grape pomace (GP) is a by-product resulting from the wine industry and can be considered raw material for animal nutrition, mainly due to its richness in polyphenolic substances. The present study, determined the antioxidant activity of GP by different in vitro assays including 1,1-Diphenyl-2-picrylhydrazyl (DPPH), superoxide anion, and hydroxyl radical and hydrogen peroxide scavenging activity and the inhibitory effect on iron-induced lipid peroxidation system. The estimated IC50 value (the concentration required to scavenge 50% of the radicals) of GP methanolic extract was 53.49 mg/L for DPPH; 57.37 mg/L for hydroxyl radical; 29.06 mg/L for superoxide radical and 102.15 mg/L for hydrogen peroxide. The effect of grape pomace supplements in broiler diets on oxidative stability of meat was tested in an experiment on 80 broiler chicks, 1-day-old Cobb 500, divided into 2 groups (C and E) reared on permanent wood shaves litter (10–12 cm thick). Compared to the control diet C, during the grower (14–28 days) and finisher (29–42 days) stages, the experimental diet (E) was supplemented with 6% GP. At the end of the experiment, 6 chicks aged 42 days from each group were slaughtered and samples of thigh meat were collected for further analysis. When the iron-induced lipid peroxidation system was applied, no significant differences were noticed between ex vivo groups’ lipid peroxidation inhibition percentage (24.71% inhibition when GP was added to meat samples and 24.10% inhibition when GP was ingested by animals) and in vivo data (26.92% inhibition) obtained.

Effect of dietary magnolia bark extract supplementation in finishing pigs on the oxidative stability of meat

BackgroundMagnolia bark extract (MBE) is a natural supplement with antioxidant, anti-inflammatory, and antimicrobial activities. Its properties suggest that the dietary supplementation in livestock could improve the quality of products. Therefore, the aim of this study was to investigate, for the first time, the effect of dietary MBE supplementation (0.33 mg/kg) in finishing pigs on the oxidative stability of meat. Oxidative stability is of paramount importance for pork, as it affects storage, retail, and consumer acceptance. For the purpose, the fatty acid profile, cholesterol, fat-soluble vitamins, antioxidant enzymes (catalase, glutathione peroxidase, and superoxide dismutase), non-enzymatic antioxidant capacity (TEAC, FRAP, and Folin-Ciocalteu assays), color stability, and lipid stability of pork were assessed.ResultsConcerning carcass characteristics, dietary MBE did not affect cold carcass yield, but reduced (P = 0.040) the chilling weight loss. The meat from pigs fed MBE had a lower (P = 0.031) lightness index than the control meat. No effect on intramuscular fat, cholesterol, and fatty acid profile was observed. Dietary MBE did not affect the content of vitamin E (α-tocopherol and γ-tocopherol) in pork, whereas it reduced (P = 0.021) the retinol content. The catalase activity was 18% higher (P = 0.008) in the meat from pigs fed MBE compared with the control group. The MBE supplementation reduced (P = 0.039) by 30% the thiobarbituric acid reactive substances (TBARS) in raw pork over 6 d of aerobic refrigerated storage. Instead, no effect on lipid oxidation was observed in cooked pork. Last, the meat from pigs fed MBE reduced Fe3+-ascorbate catalyzed lipid oxidation in muscle homogenates, with a lower (P = 0.034) TBARS value than the control group after 60 min of incubation.ConclusionsDietary MBE supplementation in finishing pigs delayed the lipid oxidation in raw meat. This effect was combined with an increased catalase concentration. These results suggest that dietary MBE could have implications for improving the shelf-life of pork.

Influence of almond hulls in lamb diets on animal performance and meat quality

Almond hulls (AH) were fed to lambs to study effects on performance and meat quality. Thirty Sarda lambs were allotted to three experimental groups and fed for 40 days either a cereal-based concentrate diet (control) or diets in which cereals were replaced with 15% (AH15) or 30% (AH30) almond hulls on a DM basis. Diets did not affect final body weight, dry matter intake, average daily gain, feed conversion ratio or carcass weight. Replacing part of the cereal mix (i.e., barley and maize) with AH did not affect meat fatty acid profiles. After 5 and 7 days of refrigerated storage respectively for cooked and raw meat, AH15 and AH30 treatments reduced meat lipid oxidation (P < 0.001). Our results suggest feeding almond hulls up to 30% in fattening lamb diets can improve meat oxidative stability without compromising growth performance.

Soybean oil and selenium yeast levels in the diet of rabbits on performance, fatty acid profile, enzyme activity and oxidative stability of meat

The objective was to evaluate the effectiveness of selenium yeast (Se, 0 and 0.15 mg/kg) as an antioxidant agent and its incorporation into meat when associated with different levels of soybean oil (SO, 1.5% and 3.0%) in the diet of rabbits. Rabbit meat was evaluated for chemical composition, fatty acid profile, enzymatic activity and oxidative stability. The increase in the soybean oil level promoted better incorporation of selenium in the meat. The 3.0% SO level improved the fatty acid profile of the meat, promoting a better saturated/unsaturated ratio and increased linoleic acid deposition. Malondialdehyde values in meat were affected by storage time and by the addition of selenium in the diet. Thus, the higher SO levels contributed to improve the saturated/unsaturated fatty acid ratio, which was directly influenced by the meat storage time. On the other hand, supplementation with Se yeast promoted better elongase enzyme activity, aiding in the production of eicosanoic acid and decreased lipid oxidation of rabbit meat.

Innovative Use of Olive, Winery and Cheese Waste By-Products as Functional Ingredients in Broiler Nutrition.

The purpose of this study was to evaluate the dietary use of novel silage that was created by combining three agro-industrial wastes produced in bulk, i.e., olive mill wastewater, grape pomace, and deproteinized feta cheese whey, in the diets of broiler chickens. A total of 216 one-day-old male Ross-308 chicks were randomly allocated to three treatment groups with six replications (12 chicks per pen). Three isocaloric and isonitrogenous diets were formulated to include the examined silage at 0%, 5%, or 10%. Commercial breeding and management procedures were employed throughout the trial. At the end of the trial (day 35), tissue samples were collected for analysis. Feeding 10% silage resulted in increased (p ≤ 0.001) final body weight (p ≤ 0.001) and feed intake. Jejunum and cecum microflora, as well as breast and thigh meat microflora, were modified (p ≤ 0.05) by the dietary inclusion. Thigh meat oxidative stability was improved (p < 0.01) by the silage supplementation. In addition, breast and thigh meat fatty acid profiles were different, respectively, (p < 0.05) in the supplemented treatments compared to the control. The examined silage was successfully tested in broiler diets with potential benefits for their performance and meat quality.

Influence of Dietary Inclusion of Exhausted Bergamot By-Product in Pigs on Animal Performance, Fatty Acid Profile and Oxidative Stability of Meat and Meat Products.

Simple SummaryThe pharmaceutical industry is increasingly interested in the extraction of phenolic compounds from bergamot pulp, which becomes less available for use in animal feeding. On the other hand, the extraction of phenol compounds generates a new bergamot by-product characterized by a low moisture content and a small concentration of phenolic compounds which are residual after extraction. In light of the above, the aim of the present study was to investigate the effect of supplementation of exhausted bergamot by-product in pigs’ performance and on the quality of meat and meat products.An investigation was carried out on the effect in pig diet of supplementation with exhausted bergamot by-product, stemming from pharmaceutical industry after extraction of phenolic compounds, on growth performance and on the quality of meat and meat products. Twenty pigs were assigned to two dietary treatments and fed a conventional concentrate (control) or a concentrate including exhausted bergamot by-product at the level of 15% on a DM basis (EB). No significant differences between dietary treatments were found for final weight (p = 0.243), carcass weight (p = 0.679), dry matter intake (p = 0.321). In EB pork, the proportion of docosapentaenoic acid was significantly increased (p < 0.05); it tended to have a greater proportion of n-3 PUFA (p = 0.09), and the n-6/n-3 PUFA ratio was lower in EB treatment (p = 0.01). In salami from EB pigs fed, the proportion of α-linolenic acid and the total n-3 PUFA were higher than in the control group (p < 0.001). In salami, the TBARS value was lower after 5 days of storage (p < 0.001) in the EB group. Therefore, the present results suggest that the inclusion of exhausted bergamot by-product in pig diet resulted in a qualitative improvement of meat and meat products.

Dietary Orange Pulp and Organic Selenium Effects on Growth Performance, Meat Quality, Fatty Acid Profile, and Oxidative Stability Parameters of Broiler Chickens

In this study, orange pulp (OP) and/or organic Se were fed to broilers in order to investigate their effects on the performance, behavior, breast meat quality, and oxidative stability. A total of 240 chicks were allocated to four groups: a control group; an OP group, fed with OP at 50 g/kg of diet; a Se group, fed with organic Se at 0.15 ppm; and an OP + Se group, fed with OP and organic Se at 50 g/kg and 0.15 ppm, respectively. The selenium and OP + Se groups showed improved meat oxidative stability during frozen storage from 90 to 210 days (p &lt; 0.05), whereas the performance and meat quality were unaffected by the dietary treatments (p &gt; 0.05), apart from a reduction in the meat pH and the dressing percentage in the OP-supplemented groups (p &lt; 0.05). A synergistic action between OP and Se was observed for the meat oxidative stability. The polyunsaturated fatty acid (FA) and α-linolenic acid (ALA) contents in the breast meat lipid fractions were increased in the OP groups (p &lt; 0.05). Dietary intervention did not affect the feeding or drinking behaviors of the broilers (p &gt; 0.05). The dietary supplementation of broiler chickens with the citrus industry byproduct orange pulp at 50 g/kg, along with organic Se at 0.15 ppm, beneficially improves the meat oxidative stability and the meat nutritional value, with no negative side effects on the performance or the meat quality.

Effects of dietary flaxseed oil with or without products with antioxidant properties on pig performance, carcass characteristics, meat quality and oxidative stability

Context The inclusion of natural products with antioxidant properties in animal diets as well as the use of different lipid sources has been tested to improve the nutritional quality of meat. Aim The aim of this work was to compare natural products with antioxidant properties and vitamin E in swine diets containing flaxseed oil. Methods Ninety-six animals were allocated to six treatments: control diet (C), diet with 3% flaxseed oil (F), diet with 3% flaxseed oil + 10% grape pomace (FGP), diet with 3% flaxseed oil + 0.0022% grape seed extract (FGE), diet with 3% flaxseed oil + 5% Nile tilapia carcass hydrolysate (FH), and diet with 3% flaxseed oil + 200 ppm vitamin E supplement (FVitE). Key results The treatments had no effect on growth performance or serum total antioxidant status, while low-magnitude effects on carcass traits were observed. The addition of flaxseed oil to the diet increased the omega-3 and total polyunsaturated fatty acid concentrations and decreased saturated fatty acid and monounsaturated fatty acid concentrations in meat; high concentrations of total tocopherol were observed in the treatments FVitE, FGE, and FH, while a higher oxidative stability (Rancimat®) of backfat was observed for the treatment FVitE. The thiobarbituric acid-reactive substances assay and the sensory evaluation of mini-burgers revealed that vitamin E was the most efficient antioxidant throughout the storage, although the treatments FH and FGE have presented a mild effect. Conclusions Problems of oxidative stability of pork resulting from including flaxseed oil in the diet of pigs due to increases in omega-3 fatty acids were better overcome by dietary vitamin E than by the use of the other natural antioxidants assessed here. However, this study also demonstrated that both the tilapia hydrolysate and grape seed extract have potential to be used as natural antioxidants, although further studies are required. Implications The results impact the meat industry in regard to the nutritional quality and oxidative stability of meat. Pork with higher omega-3 content and natural antioxidants can meet consumer demand for a healthier diet, besides providing higher stability throughout storage, providing an additional market niche for the pork industry.

Growth Performance, Meat Quality and Antioxidant Status of Sheep Supplemented with Tannins: A Meta-Analysis.

Simple SummaryTannins can be used to improve productive performance, meat quality and antioxidant status of ruminants. The objective of this study was to evaluate the effects of dietary tannin supplementation on productive performance, carcass characteristics, meat quality and blood serum antioxidant status of sheep through a meta-analysis. Only studies with weaned or older sheep were included. The sheep included in the present study were between 2 and 6 months old, and between 12 and 31 kg of body weight. Tannin supplementation improved productive performance, carcass yield, meat oxidative stability and blood serum antioxidant capacity. This suggests that the inclusion of tannins in sheep diets could be used to improve growth and reduce oxidative stress in animals, and to improve meat quality and shelf life.The objective of this study was to evaluate the effects of dietary supplementation with tannins (TANs) on productive performance, carcass characteristics, meat quality, oxidative stability, and blood serum antioxidant capacity of sheep through a meta-analysis. Using Scopus, Web of Science, ScienceDirect, and PubMed databases, a systematic search was performed for studies published in scientific journals that investigated the effects of TANs supplementation on the variables of interest. Only studies with weaned or older sheep were included. The data analyzed were extracted from 53 peer-reviewed publications. The sheep included in the present study were between 2 and 6 months old, and between 12 and 31 kg of body weight. The effects of TANs were analyzed using random-effects statistical models to examine the standardized mean difference (SMD) between treatments with TANs and control (no TANs). Heterogeneity was explored by meta-regression and a subgroup analysis was performed for covariates that were significant. Supplementation with TANs did not affect dry matter intake, pH, color (L* and b*), Warner–Bratzler shear force, cooking loss and meat chemical composition (p > 0.05). Supplementation with TANs increased daily weight gain (SMD = 0.274, p < 0.05), total antioxidant capacity (SMD = 1.120, p < 0.001), glutathione peroxidase enzyme activity (SMD = 0.801, p < 0.001) and catalase (SMD = 0.848, p < 0.001), and decreased malondialdehyde (MDA) concentration in blood serum (SMD = −0.535, p < 0.05). Supplementation with TANs decreased feed conversion rate (SMD = −0.246, p < 0.05), and the concentration of MDA (SMD = −2.020, p < 0.001) and metmyoglobin (SMD = −0.482, p < 0.05) in meat. However, meat redness (SMD = 0.365), hot carcass yield (SMD = 0.234), cold carcass yield (SMD = 0.510), backfat thickness (SMD = 0.565) and the Longissimus dorsi muscle area (SMD = 0.413) increased in response to TANs supplementation (p < 0.05). In conclusion, the addition of tannins in sheep diets improves productive performance, antioxidant status in blood serum, oxidative stability of meat and some other characteristics related to meat and carcass quality.

Does Pleurotus ostreatus influence health status and meat quality attributes of broiler chickens?

An 8-week study was piloted to establish the effect of Pleurotus ostreatus (PO) extract (Oyster mushroom) on health status and quality attributes of meat. One hundred and eighty (180) day old Cobb chicks were allotted into three treatments and orally administered extract of Pleurotus ostreatus at 0 (control), 2000 and 4000 mg/L. Haematological indices, serum metabolites, quality attributes of meat and oxidative stability of meat were determined. Oral administration of PO had no effect on haematological indices and some serum metabolites except serum albumin and calcium. Thiobarbituric acid (TBARs) in blood was lowered in 4000 mg/L group at week 4 and 8 of growth. Crude protein and water holding capacity (WHC) increased as level of oral administration of PO increased with the highest values in 2000 mg/l and 4000 mg/L groups. Glutathione Peroxidase (GSH-Px) activity in meat tissue was highest in the 4000 mg/L treatment while Thiobarbituric Acid Reactive Substances was statistically lowest and similar in the control and 4000 mg/L groups. It is concluded that Pleurotus ostreatus extract can be orally administered up to 4000 mg/L as an antioxidant in birds in order to decrease lipid peroxidation in birds and improve meat quality and oxidative stability.

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

Simple SummarySelenium 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.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.

Influence of the Application of Organic Selenium in Duck Concentrate Mixtures on the Sensory Properties of Duck Meat

There are data in the literature on the influence of higher amounts of organic selenium on production results, and the obtained results indicate that high levels of organic selenium added to feed (even up to 15 mg / kg) of chickens did not have a negative effect on production results. Also, in the literature related to chicken nutrition there is data on the use of different forms (inorganic, organic) and different amounts of selenium on carcass meat, pH value of meat, ability to bind water, chemical parameters of meat quality, oxidative stability of meat, and and on the sensory properties of broiler meat. Of particular importance are the studies of the possibility of using increased amounts of organic selenium in poultry nutrition in order to enrich meat with selenium. This is of particular importance for the nutritional value of meat, and in connection with this, human health. The aim of this study was to investigate the effect of adding different amounts of organic selenium (ALKOSEL® R397) in concentrate mixtures on the sensory properties of meat streams.

Effect of feeding pigs with bergamot by-product on fatty acid composition and oxidative stability of meat and salami

This work investigated the effects of feeding ensiled bergamot pulp to pigs on meat and salami quality. Eighteen pigs were assigned to two experimental treatments and fed a cereal-based concentrate diet (control) or the same diet in which ensiled bergamot pulp replaced 15% dry matter of the diet fed (BP). The BP treatment increased α-linolenic acid (+250%; P<0.05), docosapentaenoic acid (+62%; P<0.05), docosahexaenoic acid (+43%; P<0.05) and consequently n-3 PUFA (+15%; P<0.01) in meat. In salami, the content of α-linolenic acid, total PUFA and n-3 PUFA increased (+320%, +25% and+258%, respectively) by feeding the BP diet (P<0.001). The inclusion of bergamot pulp in the diet did not alter the oxidative stability in raw and cooked meat and colour descriptors. In salami, TBARS values were lower after 5days of storage (P<0.001) in BP group (1.54 vs 2.96). Finally, dietary supplementation with ensiled bergamot pulp to pigs improved the nutritional value of meat and meat products.

Growth pattern, lipid composition, oxidation status, and serum biochemical profile of broiler chicken fed flaxseed meal for different durations

This research studied the effects of flaxseed meal (FSM) feeding for different durations on growth performance, fatty acid profile, oxidative stability of meat, and serum biochemical profile of broiler chicken. In basal diet 100 g FSM replaced soybean meal. The FSM based diet was fed for different durations resulting in six dietary treatments viz. T1 (0-5 weeks), T2 (1-5 weeks), T3 (2-5 weeks), T4 (3-5 weeks), T5 (4-5 weeks), and T6 (without FSM). The results revealed significant negative effects of FSM feeding beyond 3 weeks duration (2-5 weeks) on the weight gain, feed efficiency, production efficiency factor, protein efficiency ratio, and energy efficiency ratio of broiler chicken. Significant improvement of fatty acid profile of chicken meat was observed by FSM feeding up to 3 weeks only. Increasing the FSM feeding beyond 1 week in case of thigh meat and 2 weeks in case of breast meat significantly decreased the antioxidant capacity of broiler chicken meat. The lipid oxidation of broiler chicken meat increased significantly by feeding FSM beyond 2 weeks. Increase in the duration of FSM feeding has significantly decreased the serum triglyceride, cholesterol, cardiac risk ratio, atherogenic coefficient, and atherogenic index of plasma, though, the decline was not significant beyond the 2 weeks (3-5 weeks) feeding duration. The progressive increase in serum HDL cholesterol, serum antioxidant enzyme activities, and MDA concentration was observed with increase of FSM feeding duration. Thus, the 100 g FSM feeding for 2 weeks duration (3-5 weeks) has no negative effect on the growth performance with better health indices and serum biochemical profile of broiler chicken. However, increasing the duration of feeding beyond 1 week (4-5 week) exerts negative effects on the oxidative stability of meat and serum antioxidant enzyme profile.

Impact of Fermented or Enzymatically Fermented Dried Olive Pomace on Growth, Expression of Digestive Enzyme and Glucose Transporter Genes, Oxidative Stability of Frozen Meat, and Economic Efficiency of Broiler Chickens.

The use of dried olive pomace as complementary energy sources in poultry feed is still limited due to its low protein and high fiber contents. Bioconversion of olive pomace through solid-state fermentation with or without exogenous enzymes is considered as a trial for improving its nutritional value. This study aimed to evaluate the effects of fermented olive pomace with or without enzymatic treatment on the growth, modulations of genes encoding digestive enzymes and glucose transporters, meat oxidative stability, and economic efficiency of broiler chickens. A total of 1400 day-old broiler chicks (Ross 308) were randomly allocated to seven dietary treatments with 10 replicates of 20 birds/replicate. Treatments included control (basal corn–soybean diet) and other six treatments in which basal diet was replaced by three levels (7.5, 15, and 30%) of fermented olive pomace (FOPI) or enzymatically fermented olive pomace (FOPII) for 42 days. The highest body weight gain was observed in groups fed 7.5 and 15% FOPII (increased by 6.6 and 12.5%, respectively, when compared with the control group). Also, feeding on 7.5 and 15% FOPII yielded a better feed conversion ratio and improved the digestibility of crude protein, fat, and crude fiber. The expression of the SGLT-1 gene was upregulated in groups fed FOPI and FOPII when compared with the control group. Moreover, the expression of the GLUT2 gene was elevated in groups fed 7.5 and 15% FOPII. By increasing the levels of FOPI and FOPII in diets, the expression of genes encoding pancreatic AMY2A, PNLIP, and CCK was upregulated (p < 0.05) when compared with the control. Fat percentage and cholesterol content in breast meat were significantly reduced (p < 0.05) by nearly 13.7 and 16.7% in groups fed FOPI and FOPII at the levels of 15 and 30%. Total phenolic and flavonoid contents in breast meat were significantly increased in groups fed 15 and 30% FOPI and FOPII when compared with the control group and even after a long period of frozen storage. After 180 days of frozen storage, the inclusion of high levels of FOP significantly increased (p < 0.05) the levels of glutathione peroxide and total superoxide dismutase and meat ability to scavenge free radical 1,1-diphenyl-2-picrylhydrazyl. Furthermore, the highest net profit and profitability ratio and the lowest cost feed/kg body gain were achieved in groups fed 7.5 and 15% of FOPII, respectively. The results of this study indicated that dietary inclusion of 15% FOPII could enhance the growth performance and economic efficiency of broiler chickens. Moreover, a higher inclusion level of FOPI or FOPII could enhance the quality and increase the oxidative stability of frozen meat and extend the storage time.

Effects of Grape Seed Oil Supplementation to Broilers Diets on Growth Performance, Meat Fatty Acids, Health Lipid Indices and Lipid Oxidation Parameters

The purpose of this study was to evaluate the effects of grape seed oil (GSO) supplementation to broilers fed polyunsaturated fatty acids (PUFA)-enriched diets on growth performance, color, texture, fatty acid content and lipid peroxidation of meat. The 4-week feeding trial was conducted on 120 Cobb 500 broilers, assigned to three groups and housed in an experimental hall on permanent wood shaves litter. GSO was tested as source of natural antioxidants at different levels, 0% (GSO0, control), 1.5% (GSO1.5) and 3% (GSO3) in the presence of 4% flaxseed meal (FSM) in a completely randomized design. The results show that at the end of the experiment (42 days) the GSO supplementation had no effect (p &lt; 0.05) on productivity parameters, except the final weight which was improved in GSO3 compared to GSO. The thigh meat color indicated a higher degree of lightness (p &lt; 0.05), but the meat texture was not influenced (p &lt; 0.05) by the new tested diets. The GSO diets increased (p &lt; 0.05) the saturated fatty acid (SFA) content and decreased the PUFA content in the thigh meat. Thigh meat samples from GSO treatments had significantly (p &lt; 0.05) improved oxidative stability. In the breast meat only the concentration of thiobarbituric acid-reactive substances (TBARS) decreased (p &lt; 0.05). It is concluded that the GSO significantly improved the thigh meat oxidative stability.

Feeding Broiler Chickens with Grape Seed and Skin Meals to Enhance α- and γ-Tocopherol Content and Meat Oxidative Stability.

Grape seeds (GS) and grape skins (GK) are natural sources of polyphenols with featured antioxidant capacity. An experiment was conducted to investigate the effect of these polyphenol sources in diets formulated to contain the same total extractable grape polyphenol content on growth performance, protein and extractable polyphenol digestibility, plasma and meat α- and γ-tocopherol and thigh meat oxidation in broiler chickens. Five experimental diets were formulated: control, control + vitamin E (200 mg/kg), 30 g/kg GS diet, 110 g/kg GK diet, GS + GK diet (a mixture of 24.4 g/kg GS and 13.1 g/kg GK designed to simulate a reconstituted grape pomace). Feeding chickens with 110 g/kg GK reduced (p < 0.001) daily weight gain, worsened (p < 0.001) feed conversion ratio, increased (p < 0.001) non-extractable polyphenol content in the ileum and in the excreta and decreased (p < 0.05) ileal protein digestibility. Regardless of the grape polyphenol source used, the inclusion of grape byproducts in the diets led to an increase of total extractable polyphenol contents in the ileum (p < 0.01) and the excreta (p < 0.001), which resulted (p < 0.001) in a decrease of extractable polyphenol digestibilities. Alpha- and gamma-tocopherol concentrations increased (p < 0.001) in plasma and in seven-day stored meat in birds fed the diet combining GS and GK with respect to the control group. As it happened with the vitamin E supplementation, feeding the combination of GS and GK also reduced (p < 0.001) the concentration of the lipid peroxidation marker (malondialdehyde) in the stored meat of chickens.