The effect of quercetin dietary supplementation on meat oxidation processes and texture of fattening lambs

Cardioprotective properties of quercetin in fescue toxicosis-induced cardiotoxicity via heart-gut axis in lambs (Ovis Aries)

The present study investigated whether quercetin mitigated fescue toxicosis-induced cardiovascular injury via the heart-gut axis. Twenty-four commercial Dorper lambs were stratified by body weight and assigned randomly to diets in one of four groups: endophyte-free without quercetin (E-,Q-), endophyte-positive without quercetin (E+,Q-), endophyte-positive plus 4 g/kg quercetin (E+,Q+) or endophyte-free plus 4 g/kg quercetin (E-,Q+) for 42 days. Body weight and average daily feed intake (ADFI) of lambs fed the endophyte-positive diets showed significant decreases. However, in the groups treated with quercetin, there were significant alterations of cardiac enzymes. Furthermore, reduced fescue toxicosis-induced histopathological lesions of heart and aorta were demonstrated in the E+,Q+ lambs. Results also suggested quercetin eased cardiovascular oxidative injury by inhibiting the increase of oxidative metabolites, and enhancing the levels of antioxidases. Quercetin reduced the inflammation response through suppressing NF-κB signaling pathway activation. Additionally, quercetin ameliorated fescue toxicosis-induced mitochondria dysfunction and improved mitochondrial quality control through enhancing PGC-1α-mediated mitochondrial biogenesis, maintaining the mitochondrial dynamics, and relieving aberrant Parkin/PINK-mediated mitophagy. Quercetin enhanced gastrointestinal microbial alpha and beta diversity, alleviated gut microbiota and microbiome derived metabolites-SCFAs dysbiosis by fescue toxicosis. These findings signified that quercetin may play a cardio-protective role via regulating the heart-gut microbiome axis.

Mixed oats and alfalfa improved the antioxidant activity of mutton and the performance of goats by affecting intestinal microbiota

Oat hay and alfalfa hay are important roughage resources in livestock production. However, the effect of the mixture of oat hay and alfalfa hay on the meat quality of Albas goats is unclear. This study aimed to investigate the effects of feeding different proportions of oat hay and alfalfa hay on the growth performance and meat quality of Albas goats. Therefore, 32 goats were fed for 70 days and randomly divided into four treatment groups on the principle of similar weight: whole oat group (OAT), oat alfalfa ratio 3:7 group (OA73), oat alfalfa ratio 7:3 group (OA37) and whole alfalfa group (Alfalfa), with eight goats in each group. Daily feed intake records, feces, feed samples, and rumen fluid collection were made throughout the trial. The goats were weighed on the last day of the trial, and four goats per group were randomly selected for slaughter. Cecum contents, meat samples, and hot carcass weight were collected, and data were recorded. Furthermore, the relationship between the rumen and cecal microbes on performance and meat quality was clarified by analyzing the rumen and hindgut microbiomes. The results showed that feeding alfalfa could significantly reduce the daily weight gain of fattening goats. Compared with the highest group (OA37), the daily weight gain decreased by 19.21%. Although there was no significant change in feed intake in the four treatments, the feed conversion rate of the alfalfa group significantly decreased by 30.24-36.47% compared to the other groups. However, with the increased alfalfa content, MDA decreased significantly, T-AOC was up-regulated, and the antioxidant activity of the fattened goat meat fed with the high alfalfa group was significantly higher than that of the low alfalfa group. Notably, the abundance of Bacteroidales_unclassified and Clostridium were strongly correlated with T-AOC and MDA. Therefore, increasing the proportion of alfalfa in the diet can affect the antioxidant activity of goat meat by improving the gut microbiota, while an oat-hay mixture can improve the growth performance of livestock.

Quercetin ameliorates chicken quality by activating the PI3K/PKB/AMPK signaling pathway in broilers

This study was conducted to investigate the effects and mechanism of quercetin on chicken quality in broilers. We selected 480 AA broilers (1 day old) and randomly allotted those to four treatments (negative control and 0.2, 0.4, or 0.6 g of quercetin per kg of diet) for 42 days. Compared with the control group, the supplementation with 0.4 g of quercetin significantly increased the pH_45min and L ^* value of the thigh muscle and decreased the shearing force of the thigh muscle and breast muscle and drip loss of the thigh muscle (P < 0.05). The supplementation with 0.6 g/kg of quercetin significantly increased the pH_45min and L ^* value of the thigh muscle, and pH_45min of breast muscle and decreased the drip loss of the thigh muscle (P < 0.05). Sensory scores of meat color, tenderness, and juiciness also were improved with increasing quercetin concentration (P < 0.05). The inosinic acid (IMP) content of the breast and thigh muscles of broilers was significantly increased by supplementation with 0.6 g/kg of quercetin (P < 0.05). Supplementation with 0.2, 0.4, and 0.6 g of quercetin significantly reduced mRNA expression of L-FABP (P < 0.05, P < 0.05, and P < 0.05); supplementation with 0.4 and 0.6 g/kg of quercetin significantly increased mRNA expression of PKB and AMPKα1 (P < 0.05 and P < 0.05); supplementation with 0.6 g/kg of quercetin in the diet significantly reduced mRNA expression of SREBP1 and HMGR (P < 0.05 and P < 0.05) and significantly increased mRNA expression of CPT1 and PPARγ (P < 0.05 and P < 0.05); and supplementation with 0.2, 0.4, and 0.6 g/kg of quercetin significantly increased mRNA expression of PI3K, LPL, and Apo A1 and significantly reduced mRNA expression of ACC and FATP1 in the breast muscle of broilers (P > 0.05). PI3k, PKB, AMPK, SREBP1, and L-FABP were significantly and positively correlated with pH_45min (P < 0.05); PPARγ was significantly and positively correlated with shear force (P < 0.05); CPT1 was significantly and positively correlated with the L ^* value (P < 0.05); and HMGR was significantly and positively correlated with drip loss (P < 0.05). In conclusion, quercetin improved the meat quality, protecting it against lipid oxidation and deposition by regulating the PI3K/PKB/AMPK_α1 signaling pathway in the breast muscle of broilers.

Effects of dietary resveratrol supplementation on the chemical composition, oxidative stability and meat quality of ducks (Anas platyrhynchos)

The effects of dietary resveratrol (0, 300, 400 and 500 mg/kg) on the chemical composition, antioxidative capacity, meat quality and volatile compound concentrations of duck meat were investigated. The results showed that dietary resveratrol had no significant effects on the chemical composition. Dietary resveratrol supplementation increased superoxide dismutase, glutathione peroxidase, catalase activity, pH_{15 min}, pH_{24 h} and color, and reduced the malondialdehyde, and carbonyl contents and shear force, thereby improving water mobility and distribution (T_2b, T₂₁, T₂₂), drip loss, cooking loss and volatile compounds concentration of duck meat. In conclusion, dietary resveratrol supplementation improved the meat quality of ducks by enhancing the antioxidant capacity, improving the color and shear force, and suppressing lipid and protein oxidation, and 500 mg/kg dietary resveratrol had the greatest effect in this study.

The effects of dietary quercetin supplementation on the meat quality and volatile profile of rabbit meat during chilled storage

Thirty-four New Zealand White rabbits of both sexes were fed a control or supplemented (2 g/kg quercetin dihydrate) diet from weaning until slaughter (13 weeks). After post-mortem chilling, excised and minced Longissimus thoracis et lumborum muscles were stored at 3.2 °C under oxygen-permeable wrapping for 1, 3 or 5 days. Colour, pH, lipid oxidation (TBARS), antioxidant capacity (FRAP), volatile profile (day 1 and 5) and microbial count (day 5) were determined. Quercetin reduced alkane (day 5) and hexanal (day 1) concentrations, but otherwise had minimal antioxidant effect, and did not benefit microbial quality, and thus did not substantially improve the shelf-life. The sex effect was similarly limited. Overall, the pH increased and FRAP decreased during storage, but TBARS did not change and discolouration seemed delayed. The volatile profile was dominated by esters, alcohols and heterocyclic compounds, and while it changed during storage, lipid oxidation products did not increase as expected, suggesting that rabbit meat may have relatively active reducing mechanisms.

Grain grinding size of cereals in complete pelleted diets for growing lambs: Effects on animal performance, carcass and meat quality traits

The main goal of the present study was to clarify the effects of different grinding particle size of grains (2-mm vs. 6-mm) included in complete pelleted diets (CPD) for fattening lambs on animal performance, carcass and meat quality. Twenty male merino lambs (14.8 kg; n = 10 per group) were fed the corresponding diet ad libitum and slaughtered when they reached 27 kg. No differences were observed in the feed conversion ratio or carcass characteristics. However, lambs fed coarser diets (6 mm) were more efficient with less residual feed intake (-14.0 vs. 15.4 g DM/animal/d; P < .05) than lambs fed the 2 mm CPD. Lambs fed the 6-mm CPD showed higher levels of intramuscular fat and saturated fatty acids. Consequently, increasing the particle size of the grains included in CPD allows for improving feed efficiency and intramuscular fat in fattening lambs.

Grape pomace in ewes diet: Effects on meat quality and the fatty acid profile of their suckling lambs

Grape pomace (GP) is an inexpensive natural antioxidant promising as animal feed supplement due to its high content of phenolic compounds. In order to evaluate its effect in lactating ewe rations on meat quality and fat composition of their suckling lambs, 48 Churra ewes were divided into 4 treatments. All animals were fed a ration containing linseed oil (Control) supplemented with Vitamin E or two levels of GP. Lambs were nourished exclusively by suckling until they were slaughtered. Dietary GP did not generate adverse effects on carcasses or lambs meat quality when compared with Control or Vit-E diets. GP improved the water holding capacity of the meat. In addition, lambs meat FA profile was not nutritionally affected with the diets assayed. Hence, the use of GP as a dietary supplement in ewe rations would not have negative effects on meat from suckling lambs.

Effects of dietary supplementation with polyphenols on meat quality in Saanen goat kids

Background

Diet supplementation with polyphenols is a novel strategy to improve meat quality in livestock, by preventing oxidative deterioration of lipids and protein. Polyphenols have beneficial effects on both human and animal health and can be obtained from several sources, such as olive mill wastewaters (OMWW). These are severe environmental pollutants and therefore may be recycled and utilized in other sectors. The aim of this study was to evaluate growth performance, meat characteristics, fatty acid composition, antioxidant status, different forms of myoglobin and malondialdehyde formation in kids who received a diet supplemented with polyphenols obtained from OMWW. Weaned goat kids (n = 18) were divided into two homogenous groups: control (C) group (n = 9) received a fattening standard diet while the other group (n = 9) received the same diet, supplemented with 3.2 mg/day of polyphenols powder extract (PE group). Average daily gain (ADG) was calculated 10 days apart throughout the study. After 78 days, the kids were slaughtered and pH and carcass yield were evaluated. Longissimus thoracis et lumborum muscle was collected and utilized for chemical analysis, meat quality evaluation and oxidative stability.

Results

No differences were recorded in ADG, carcass weight, pH and dressing between the two groups. Furthermore a similar meat proximate composition, texture and color was observed. Dietary polyphenols supplementation significantly (P < 0.01) decreased short chains (<C12:0) (2.93 + 0.50 and 0.35 + 0.40 g/100 g of fatty acids, for C and PE Group, respectively), and saturated (49.22 ± 2.39 and 39.51 ± 1.95 g/100 g, in C and PE Group, respectively) fatty acids. Furthermore, a higher (P < 0.05) proportion of monounsaturated (34.35 ± 2.84 and 42.22 ± 2.32 g/100 g, in C and PE Group, respectively) fatty acids was recorded. Malondialdehyde formation was significantly (P < 0.05) lower in PE compared to C Group (0.25 ± 0.005 and 0.15 ± 0.005, in C and PE Group, respectively).

Conclusions

Polyphenols dietary supplementation has positive effects on kid meat, improving fatty acid profile and reducing malondialdehyde contents. Furthermore the utilization of OMWW as the source of polyphenols may represent an innovative strategy to re-utilize agri-food industry wastes.

Assessment of the antioxidant effect of astaxanthin in fresh, frozen and cooked lamb patties

Astaxanthin is a natural red carotene exerting a strong antioxidant action. The effect of this carotene on the oxidative stability of raw and cooked lamb patties was evaluated. Seven experimental treatments were included in this study depending on the antioxidants added, which are: no antioxidant added (control), 450 mg/kg of sodium metabisulphite, 500 mg/kg of sodium ascorbate, and 20 mg/kg, 40 mg/kg, 60 mg/kg and 80 mg/kg of astaxanthin. The raw patties were either refrigerated for up to 11 days or frozen for 3 months under aerobic conditions. Changes in thiobarbituric reactive substances (TBARS), instrumental colour, pH and Eh were determined in the refrigerated patties and TBARS in the frozen patties. Volatile compounds were determined in cooked patties and cholesterol oxides in both cooked and after cooking microwave reheated patties. The changes in TBARS of cooked patties during a four-day refrigerated storage were also studied. Compared to the control patties, the use of astaxanthin reduced the TBARS generation in a manner depending on the dose for both raw and cooked patties during storage (P < 0.05). Astaxanthin added at levels of 60 and/or 80 mg/kg showed a greater antioxidant effect than ascorbate and metabisulphite. The presence of astaxanthin, like that of ascorbate, decreased the oxysterols levels of cooked patties with regard to controls. The amount of volatiles released from the cooked patties was also reduced by astaxanthin. This effect was not observed for ascorbate or metabisulphite. Astaxanthin in lamb patties at levels of 60-80 mg/kg could improve raw and cooked lamb patty oxidative stability during refrigerated aerobic storage, protect their lipids against thermal degradation more than ascorbate and metabisulphite, and reduce oxysterols formation during cooking in a similar way to ascorbate.

Effect of hop (Humulus lupulus L.) inclusion in the diet for fattening lambs on animal performance, ruminal characteristics and meat quality

Thirty male merino lambs were fed with a pelleted total mixed ration (TMR) alone or supplemented with hop (Humulus lupulus L.) cones at two different doses (1.5 and 3.0 g hop cones/kg pelleted TMR, respectively), to study the effects of this dietary source of antioxidants on animal performance, ruminal parameters and meat quality attributes. The results showed that dietary supplementation with hop cones decreased lambs' growth rate (P < 0.05) due to a shift in ruminal fermentation, towards a more acetic and less propionic acid production (P < 0.05). These changes in animal growth rate might have promoted microstructural modifications in the quantity and size of muscle fibres, thereby inducing the differences observed in meat chemical composition, colour and texture (P < 0.05), regardless of the lack of differences in meat antioxidant status (P > 0.10).

Effects of grape pomace in growing lamb diets compared with vitamin E and grape seed extract on meat shelf life

The effect of dietary treatment (CTRL, control; VIT-E, 500 mg kg(-1) vitamin E; GSE, 50 mg grape seed extract kg(-1); GP-5, 5% dried red grape pomace kg(-1)) on shelf life of lamb meat was studied. After slaughter (27 kg LBW), m. longissimus thoracis et lumborum was sliced, packaged under modified atmosphere (80:20%/O2:CO2) and stored in retail conditions for 14 days. At each sampling day (0, 4, 7, 11, 14), microbiological, physico-chemical and sensory characteristics were analysed. Meat from VIT-E presented lower microbial counts than CTRL, GSE and GP-5, without differences between polyphenol treatments (GSE and GP-5) and CTRL. Vitamin E reduced meat discoloration and lipid oxidation (TBARS values) from day 7 with respect to the other treatments. Although not significant, an improvement in TBARS values of about 20% was observed for GSE and GP-5, compared with CTRL, from day 7 of storage. VIT-E dietary treatment was more effective in preventing sensory spoilage than the other treatments.

Antioxidant and antimicrobial effects of dietary supplementation with rosemary diterpenes (carnosic acid and carnosol) vs vitamin E on lamb meat packed under protective atmosphere

The antioxidant and antimicrobial effects on lamb meat of the dietary use of rosemary diterpenes and vitamin E were compared. Thirty fattening lambs were assigned to three diets: (C) control; (R) C plus 600 mg kg(-1) carnosic acid and carnosol at 1:1 w:w; or (E) C plus 600 mg kg(-1) α-tocopherol. The deposition of the dietary supplements in the muscle was determined. Microbial quality (total viable counts, Lactic Acid Bacteria, Enterobacteriaceae, Escherichia coli and Salmonella spp), oxidative stability (CIELab color, malondialdehyde and total carbonyls) and sensory attributes (appearance and odor) were determined in loin stored at 2°C under 70% O2/30% CO2 atmosphere. Microbial quality was ensured by packaging and chilling. The E-diet was more effective (P ≤ 0.05) than the R-diet in preventing meat oxidation, although the latter had antimicrobial effects on meat. The shelf life of lamb (assessed as the loss of freshness) could be increased by 5 (R-diet) or 10 (E-diet) days.