Effect of thymol on the broiler chicken antioxidative defence system after sustained dietary thyme oil application

1. The purpose of this study was to examine if the concentration of thymol as the main compound of Thymus vulgaris essential oil (TEO) influenced the antioxidant defence system in broilers. 2. Twenty-four broiler chickens were randomly divided at the day of hatching into three dietary treatment groups (0%, 0.05% and 0.1%, w/w TEO) with eight birds in each and were fed until four weeks of age. 3. Thymol content in plasma, duodenal wall and breast muscle significantly increased when 0.1% of thyme oil was added to the diet (P < 0.05). Thymol concentration in plasma significantly correlated with levels measured in the duodenal wall and feed (r_s = 0.7857, P < 0.05; r_s = 0.7647, P < 0.05). Superoxide dismutase (SOD) activity increased, and malondialdehyde (MDA) concentration decreased significantly (P < 0.05) in blood from chickens fed 0.1% TEO supplementation. Although the thymol concentration did not significantly decrease MDA amounts in breast muscle, a declining trend was observed. 4. The trial data confirmed the efficient absorption of thymol from the digestive tract into the systemic circulation, but only traces were found in breast muscle. Thymol content was sufficient for expressing its antioxidant properties in blood, but its low content in breast muscle was insufficient to significantly affect lipid oxidation and fatty acid composition.

Dynamics of thymol dietary supplementation in quail (Coturnix japonica): Linking bioavailability, effects on egg yolk total fatty acids and performance traits

Phytogenic additives such as thymol are encountering growing interest in the poultry industry. However, there are still questions concerning dynamics of their bioavailability, biological action, optimal dosage and duration of supplementation needed to achieve meaningful effects, as well as persistence of induced changes after supplement withdrawal. We studied the link between the dynamics of free thymol concentration and the changes in fatty acids composition in quail egg yolk, both during a month-long chronic dietary supplementation and after 3 weeks of supplement withdrawal (post-supplementation). Fifty, 85 days-old, female quail of homogeneous body weights (251±1g) in egg-laying peak were used. To evaluate potential dose-dependent effects, three increasing doses 2, 4, and 6.25 g of thymol/kg of feed (THY2, THY4 and THY6, respectively) and two controls were evaluated (n = 10). In parallel, we assessed the concomitant changes in free thymol excretion, potential liver histopathological changes, and birds´ performance traits. Egg yolk and droppings show a dose-dependent increase in THY concentration after 9 days of supplementation and a decrease after post-supplementation. In egg yolk, these changes were accompanied by reduced saturated fatty acid concentrations achieved by 28 days of supplementation in THY2 and 14 days of supplementation in THY4 and THY6. However, after post-supplementation the aforementioned effect disappeared in THY2 but not in THY4 and THY6. While THY2 failed to increase polyunsaturated fatty acids, THY4 and THY6 increased polyunsaturated fatty acids by day 14 of supplementation and remained increased after post-supplementation. Fatty acids changes induced by thymol are consistent with improved nutritional quality of eggs. No treatment effects were observed in liver histopathology and female performance. Findings suggest that both dose of thymol and duration of supplementation modulate thymol and fatty acids concentrations in egg yolk and thymol concentration in droppings. Furthermore, the persistence of those effects after post-supplementation period is also a dose-dependent phenomenon.

Influence of Different Production Systems on the Quality and Shelf Life of Poultry Meat: A Case Study in the German Sector

Production-specific factors, such as breeding, diet, and stress, are known to influence meat quality, but the effect of different husbandry systems on the development of quality parameters and shelf life has hardly been investigated. Thus, the aim of the study was the investigation of an alternative production system based on a slow-growing, corn-fed, and antibiotics-free chicken line compared with conventional poultry production. Additionally, the effect on meat quality, microbiology, and spoilage was analyzed. In total, 221 breast filets from a German poultry meat producer were investigated. Nutritional, biochemical, and cooking loss analyses were conducted on a subset of samples 24 h after storage. The rest of the samples were stored aerobically at 4°C, and the spoilage process was characterized by investigating pH, color, lipid oxidation, microbiology, and sensory attributes subsequently every two days during storage. The alternative production line showed a significantly healthier nutritional profile with a higher protein and lower fat content. Additionally, the amount of L-lactic acid and D-glucose was significantly higher than in the conventional production line. The color values differed between both production lines, with the corn-fed line displaying more yellowish filets. The lipid oxidation and microbial spoilage were not affected by the production line. The shelf life did not differ between the investigation groups and was deemed 7 days in both cases. Despite the highest severity of white striping being observed most in the conventional production line, there was no overall difference in the incidence among groups. The purchase decision was affected by the occurrence of white striping and showed a tendency for a higher acceptance for the alternative production line.

Thymol, alpha tocopherol, and ascorbyl palmitate supplementation as growth enhancers for broiler chickens

Consumer concern on the quality of products and animal welfare has greatly increased during the past decades. Dietary synthetic antibiotic products used as growth promoters have been restricted or banned in many countries. Edible plants, essential oils, or their main components were suggested as natural feed supplements to improve growth, products' quality, and welfare-related parameters. Thymol (THY), a main component of oregano essential oil, has been proved as an effective antimicrobial and antioxidant compound. Tocopherol (TOC) evidenced antioxidant activity with potential as a growth promoter and a synergic antioxidant activity between TOC and ascorbyl palmitate (AP) has also been reported. Herein, we evaluated whether broiler diet supplementation with THY, and THY with a formulation mix containing TOC and AP (1:0.5:0.5, respectively) have potential as growth enhancers under commercial conditions. Potential protective effects against foot pad dermatitis and hock burns were also evaluated. Newly hatched male broiler chicks with similar body weight (BW) were randomly assigned to 1 of 7 groups (4 replicates each) as follows: Basal (no feed supplements added), Promotor (Basal + 6.26 μmol flavomycin/kg feed), BHT (Basal + 1.33 mmol of buthylated hidroxytoluene (BHT)/kg feed), Prom-BHT (Basal + 6.26 μmol flavomycin/kg feed + 1.33 mmol of BHT/kg feed), TOC-AP (Basal + 0.67 mmoles of TOC + 0.67 mmoles of AP/kg feed), THY (Basal + 1.33 mmoles of THY/kg feed), and THY-TOC-AP (Basal + 0.67 mmoles of THY + 0.67 mmoles of a mix 1:1 of TOC-AP). Along 7 wk, BW, feed intake, and feed conversion ratio were evaluated. Skin injuries were assessed at 35 d of age. At the end of the study (42 d), compared to Basal group, similarly enhanced final BW were observed in all groups but TOC-AP. No main differences between groups were detected in feed intake, feed conversion ratio, or skin injuries. Findings suggest that THY itself or in combination with TOC-AP may have value as a natural growth enhancer alternative for broilers.

The effect of herbal feed additive on the growth performance, carcass characteristics and meat quality of broiler chickens fed low-energy diets

The aim of this study was to determine the effect of herbal feed additive on growth performance, carcass characteristics, the chemical composition of breast muscles and selected meat quality parameters in broiler chickens. The experiment was performed on 1080 Ross 308 chickens, which were randomly divided into six groups with six replicates per group. In experimental groups, dietary energy concentration was reduced by 0.10 or 0.25 MJ kg-1, and the diets were or were not supplemented with the Superliv herbal formula at 500 g t-1 of diet. A statistical analysis revealed that Superliv had a beneficial influence on the final body weights (BWs) of birds, average daily gain (ADG), feed conversion ratio (FCR), European Efficiency Index (EEI) and the proportion of heart relative to total carcass weight. However, meat acidity measured 15 min post mortem was higher in experimental groups. A decrease in dietary energy concentration contributed to a highly significant increase in the water-holding capacity (WHC) of meat and natural drip loss, an increase in pH15, an increase in color lightness, a decrease in redness, an increase in the fat content of meat, and a decrease in malondialdehyde (MDA) concentration.

Influence of Cooking, Storage Period, and Re-heating on Production of Cholesterol Oxides in Chicken Meat

The objective of present study was to investigate the effect of cooking and their combinations with re-heating methods on the formation of cholesterol oxidation products (COPs) in stored chicken thigh meat. Pan roasting, steaming, oven grilling, charcoal grilling, and microwaving were used for cooking. Re-heating of samples was done using the same cooking methods or microwaving after 3 and 6 d of refrigerated storage. Cooking and re-heating resulted in reduction of crude fat and cholesterol contents of chicken thigh meat depending on storage period before re-heating. Cooking and storage period had no influence on the total amount of COPs. The highest total amount of COPs was observed in meat samples cooked by steaming and reheated by microwaving after 6 d of storage, which showed similar value to raw chicken meat stored for 6 days. However, different re-heating methods formed different types of COPs depending on storage period before re-heating. The high amount (p<0.05) of 25-hydroxycholesterol or α-epoxide was detected in meat samples reheated by steaming or microwaving at 3 or 6 d of storage after steamed cooking, respectively. As a result, the combination of steaming and re-heating with microwaving could increase the total amount of COPs in chicken thigh meat and different cooking/re-heating methods could form different types of COPs, even though no significant difference in the total amount of COPs depending on storage period.

Thymol as natural antioxidant additive for poultry feed: oxidative stability improvement

Antioxidant are regularly included in poultry feed as protection from deterioration during storage. Recently the interest for the use of natural phytochemicals in animal diets has been increased. Thymol (THY) has been proven to be an effective antioxidant for extending broiler meat quality during storage with similar action to the widely used butylated hydroxytoluene (BHT). This study evaluates whether THY can also have a protective effect on the feed mash by assessing its antioxidant potential and related changes in fatty acid (FA) balance. Feed mash was assigned to 1 of 4 treatments, control (CON, no additive), vehicle (VEH, ethanol 96%), BHT (400 mg BHT /kg feed) and THY (400 mg THY /kg feed). Three replicates of each treatment were taken after 0, 30, and 60 d of storage at room temperature (23 ± 3°C) and relative humidity (40 ± 5%). Peroxide value (PV), titratable acidity (TA) and FA relative composition were determined. As expected, there were no treatment effects on those variables at 0 d of storage. However, higher PV values were detected in the CON and VEH groups after 30 and 60 d of storage in comparison to the THY and BHT treated samples (CON = VEH > THY = BHT). While a slight increase was also observed in TA through storage time, no particular treatment effects were detected. Relative FA composition changed with storage time only in the CON and VEH group which had a decrease in polyunsaturated fatty acids and an increase in saturated FA. No changes were detected in the Thy and BHT treated feeds. The results suggest a similar THY and BHT protective effect on feed mash lipid oxidation. Thus, THY could be considered as a useful natural alternative to help sustain quality of poultry feed.

Addition of Capsicum oleoresin, Carvacrol, Cinnamaldehyde and their mixtures to the broiler diet II: Effects on meat quality

Background

In recent years, with the prohibition of antibiotics used as growth stimulants in the nutrition of farm animals, researchers have searched for alternative natural and reliable products in order to be able to sustain the developments experienced during the use of antibiotics and to overcome the possible inconveniences. In this context, studies on evaluation of essential oils in poultry nutrition have been reported to improve the utilization of feed, stimulate the release of digestive enzymes, increase absorption in the stomach and intestines, antimicrobial and anti-parasitic effects and thus, can be an alternative to antibiotics and improve meat quality as well. Indeed, this study has been carried out to explore the effects of the addition of 150 mg/kg capsicum oleoresin (CAP), carvacrol (CAR), cinnamaldehyde (CIN) or their mixture (CAP+CAR+CIN) into the broilers' ration over sensory, physical and chemical properties in breast meat and leg meat.

Methods

Experiments were conducted over 400 male and female broiler chicks (Ross-308) in 5 groups (1 control group and 4 treatment groups), each composed of 80 chicks. The control group was fed without feed additives while the second, third, fourth and the fifth groups were fed with 150 mg CAP/kg feed, 150 mg CAR/kg feed, 150 mg CIN/kg feed, and 150 mg CAP+CAR+CIN/kg feed, respectively.

Results

Addition of CAP, CAR, CIN or CAP+CAR+CIN had effects on the sensory (of taste, tenderness, juiciness and overall acceptability); physical properties (of L* value and toughness), the chemical properties (of DM, CF, CP, linoleic, EPA, behenic, MUFA, PUFA and ∑n-6 of the leg meat), the physical characteristics (of toughness and firmness), and the chemical properties (of CF, CP, linoleic, ecosenic, EPA, lignoseric, MUFA and ∑n-3) of the breast meat in comparison to control group. Furthermore, while the treatments had positive impacts on thawing loss, cooking loss and water holding capacity in both breast and leg meat; no effect was observed on pH value and lipid oxidation on day 1, day 4 and day 8.

Conclusion

The results strongly suggested that the addition of CAP, CAR, CIN or CAP+CAR+CIN to the rations of the broiler chicks changed the sensory, physical and chemical properties of breast and leg meat. It was also observed that these compounds were more effective when they were added to the ratio as a mixture rather than adding them individually.

Effects of dietary hop (Humulus lupulus L.) β-acids on quality attributes, composition and oxidative stability of pork meat

BACKGROUND

The effects of dietary levels of hop β-acids on physical attributes, lipid oxidation and chemical composition of pork meat were evaluated. Thirty-two castrated male pigs obtained from a complete block design feeding experiment (6.23 ± 0.42 kg initial body weight (BW) to 20.45 ± 0.95 kg final BW) and fed diets supplemented with 0, 120, 240 or 360 mg kg^-1 hop β-acids during 35 days were slaughtered to sample longissimus dorsi muscle for meat analysis.

RESULTS

No effects (P > 0.05) of dietary hop β-acids were observed on meat physical attributes. Quadratic effects (P < 0.05) of hop β-acids were observed on lipid and protein contents and on thiobarbituric acid-reactive substance (TBARS) values of meatballs, whose equations allowed the estimation of dietary hop β-acid levels of 176, 169 and 181 mg kg^-1 to provide up to 16.20% lipid reduction, 1.95% protein accretion and 23.31% TBARS reduction respectively.

CONCLUSION

Dietary hop β-acids fed to pigs might reduce lipid, increase protein and reduce lipid oxidation without affecting physical attributes of the pork meat. © 2017 Society of Chemical Industry.

Thymol feed supplementation in quail alters the percentages of nutritionally relevant egg yolk fatty acids: effects throughout incubation

BACKGROUND

Polyunsaturated fatty acids (PUFA) are crucial components of egg yolk and particularly prone to oxidative damage, generating losses of nutrients for embryonic development and influencing the quality of eggs for human consumption. The aim of this study was to evaluate whether dietary thymol (a natural antioxidant) is related to changes in quail egg yolk total (T), triglyceride (TG) and phospholipid (PL) fatty acid composition at different stages of embryo development. Thus female Japanese quail (100 days of age) were assigned to one of two dietary treatments (12 individuals each): CON (basal diet) or THY (0.0016 mol thymol day^-1 per bird). After 2 weeks of supplementation, eggs were incubated and samples were obtained at 0, 4 and 16 days of embryonic development.

RESULTS

In 0 day THY eggs, α-linolenic acid and n-3 PUFA in T and TG, docosahexaenoic acid and PUFA in T and arachidonic acid in TG were increased, while saturated fatty acids (SFA) in T were reduced. From 4 days on, PUFA, n-3 PUFA and SFA from T and TG in THY eggs were found to be similar to those of CON eggs. The changes in PL throughout incubation were similar in both dietary treatments.

CONCLUSION

Thymol would provide the embryo with PUFA for synthesis/deposition in membranes and/or assign to supply energy. Additionally, thymol supplementation would be advisable for the production of healthier table eggs. © 2017 Society of Chemical Industry.

Combination of carvacrol with simvastatin improves the lipid-lowering efficacy and alleviates simvastatin side effects

The present investigation was designed to examine the possible additive hypolipidemic effect of carvacrol (CARV) in combination with simvastatin (SIM) on poloxamer 407 (P407)-induced hyperlipidemia. Rats were injected with P407, (500 mg/ kg; i.p.), twice a week, for 30 days. Treatment was carried out by administration of SIM (20 mg/kg/day; p.o.) or CARV (50 mg/kg/day; p.o.) or combination of them. Treatment with CARV significantly decreased total cholesterol, triglycerides, low-density lipoprotein, atherogenic index, leptin, and increased high-density lipoprotein and adiponectin. Moreover, CARV potentiated the hypolipidemic effect of SIM. Both SIM and CARV alleviated the oxidative stress induced by P407. Interestingly, CARV, when combined with SIM, significantly ameliorated SIM-induced liver and muscle injury by reducing the level of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, creatine kinase, and myoglobin and restoring the normal histological picture of both liver and muscle as well as apoptosis.

The In Vitro and In Vivo Effect of Carvacrol in Preventing Campylobacter Infection, Colonization and in Improving Productivity of Chicken Broilers

The current trend in reducing the antibiotic usage in animal production imposes urgency in the identification of novel biocides. The essential oil carvacrol, for example, changes the morphology of the cell and acts against a variety of targets within the bacterial membranes and cytoplasm, and our in vitro results show that it reduces adhesion and invasion of chicken intestinal primary cells and also biofilm formation. A trial was conducted to evaluate the effects of dietary supplementation of carvacrol at four concentrations (0, 120, 200, and 300 mg/kg of diet) on the performance of Lactobacillus spp., Escherichia coli, Campylobacter spp., and broilers. Each of the four diets was fed to three replicates/trial of 50 chicks each from day 0 to 35. Our results show that carvacrol linearly decreased feed intake, feed conversion rates and increased body weight at all levels of supplementation. Plate count analysis showed that Campylobacter spp. was only detected at 35 days in the treatment groups compared with the control group where the colonization occurred at 21 days. The absence of Campylobacter spp. at 21 days in the treatment groups was associated with a significant increase in the relative abundance of Lactobacillus spp. Also, carvacrol was demonstrated to have a significant effect on E. coli numbers in the cecum of the treatment groups, at all supplementation levels. In conclusion, this study shows for the first time that at different concentrations, carvacrol can delay Campylobacter spp., colonization of chicken broilers, by inducing changes in gut microflora, and it demonstrates promise as an alternative to the use of antibiotics.

Oxidative stability and lipid oxidation flavoring volatiles in antioxidants treated chicken meat patties during storage

Background

Chicken meat contains higher percentage of polyunsaturated fatty acids that are susceptible to oxidative deterioration ultimately leading towards lower consumer acceptability for chicken meat products. Accordingly, meat processing industries are looking for combinations of natural antioxidants to enhance the oxidative stability and consumer acceptability of meat based products. The present study aimed to investigate the influence of directly added quercetin dihydrate in combination with α-tocopherol on oxidative stability, color characteristics, total carbonyls and flavor volatile compounds in chicken meat patties.

Methods

Considering the preliminary studies, 3 levels of quercetin dihdrate @ 25, 50 and 100 mg/kg meat in combination with α-tocopherol at the rate 100 and 200 mg/kg meat were added to develop chicken meat patties and were stored at refrigeration temperature for 7 days. The oxidative stability of the antioxidant treated patties was determined by measuring malonaldehydes using TBARS and total carbonyls assay. The color (Lightness, redness and yellowness) of the patties was determined by using Konica Minolta Color Meter. Moreover, the volatile compounds were measured through gas chromatography at various storage intervals.

Results

The results elucidated that quercetin dehydrate inclusion at the rate of 50 mg/kg meat as well as particularly 100 mg/kg meat decreased the oxidation by reducing generation of malonaldehydes and total carbonyls in treated patties. Highest value for TBARS at initiation of storage was reported in (T₀) as 1.93 ± 0.02 whereas lowest were reported in T₆ and T₅ as 0.37 ± 0.01 and 0.38 ± 0.03 that were increased to 3.47 ± 0.14, 0.90 ± 0.05 and 0.94 ± 0.34 at the completion of storage. Moreover, the lowest carbonyls also reported in T6 and the values at various storage intervals (1st, 3rd and 7th) were as 0.59 ± 0.025, 0.77 ± 0.015 and 1.02 ± 0.031, respectively. The antioxidants inclusion also inhibited volatile flavoring compounds particularly aldehydes like hexanal and pentanal in a dose dependent manner (p ≤ 0.05). Lowest hexanal values reported in T₆ as 2488 ± 103 followed by T₄ (3701 ± 111) at the start of the trial whereas highest in T₀ (control) as 54,768 ± 431 that were increased to 9569 ± 607, 112,550 ± 897 and 359,826 ± 1285, correspondingly. The hexanal, as a critical indicator for the determination of volatiles in meat based products, was decreased with the addition of antioxidants and its highest values were reported in control group.

Conclusions

Quercetin dihydrate addition along with alpha tocopherol is a pragmatic choice to improve oxidative storability and volatile flavor compounds in cooked meat patties. The data obtained will help meat processor to better develop antioxidant enriched formulations to augment oxidative stability and quality of processed meat products.

Thymol detection and quantitation by solid-phase microextraction in faeces and egg yolk of Japanese quail

To measure bioavailability of the active ingredients of phytogenic feed additives in poultry products and subproducts is a key element for developing a rational understanding of its mode of action and biological effects. Hence, we validated a headspace solid phase microextraction (HS-SPME) technique followed by gas chromatography-mass spectrometry as an analytical extraction procedure and as method for detection and quantitation of 2-Isopropyl-5-methylphenol (thymol) in faeces and egg yolk of quail. The suitability of this method for thymol analysis in both matrices was first proved via linearity, limit of detection, limit of quantification, and recovery using m-cresol as internal standard. The optimal HS-SPME extraction conditions were obtained at 40°C for 5min in faeces and 60°C for 30min in egg yolk. This procedure was found to be precise, sensitive and linear in the range of 2.5-100ng/gr for faeces and 20-800ng/gr for the egg yolk. Limits of detection were 0.5ng/g and 5ng/g for faeces and yolk, respectively, and the limits of quantitation were 1ng/g and 10ng/g for faeces and yolk, respectively. The method was successfully used for measuring thymol in fecal and egg yolk samples, from quails supplemented with thymol in their diets. Thus, in fresh faeces and egg yolk samples obtained from a supplemented group (80mg thymol per bird per day) were determined as 31.51ng/g for faeces and 11.83ng/g for the egg yolk.

Carvacrol reduces irinotecan-induced intestinal mucositis through inhibition of inflammation and oxidative damage via TRPA1 receptor activation

Intestinal mucositis is an inflammatory process occurring in the intestinal mucosa and is a common side effect of irinotecan hydrochloride (CPT-11) based anticancer regimens. The transient receptor potential cation channel, subfamily A, member 1 (TRPA1) receptor is highly expressed in the intestinal mucosa and has the ability to identify cell damage signaling indicates its possible association with intestinal mucositis. Carvacrol is an agonist of the TRPA1 receptor and has anti-inflammatory properties. Thus, the aim of the present study was to verify the supposed anti-inflammatory and protective action of carvacrol via TRPA1 activation against intestinal mucositis induced by CPT-11 in mice. Briefly, mice were treated with either DMSO 2% or CPT-11 (75 mg/kg, per 4 days, i.p.) or the carvacrol (25, 75 or 150 mg/kg, per 8 days, i.p.) before CPT-11. In other group, the animals were pretreated with HC-030031, a TRPA1 antagonist, 30 min before treatment with carvacrol. On day 7, animal survival and bacteremia were assessed, and following euthanasia, samples of the jejunum were obtained for morphometric analysis and measurement of antioxidant and pro-inflammatory markers. Carvacrol was found to exert an anti-inflammatory action against CPT-11-induced intestinal mucositis through strong interactions with TRPA1 receptors; reduction in the production or release or both of pro-inflammatory cytokines (TNF-α, IL-1β, and KC); and decrease in other indicators of inflammation (MPO, NF-κB, COX-2) and oxidative stress (GSH, MDA, and NOx levels). It also contributed to the restoration of the tissue architecture of the villi and crypts in the small intestine, and improved clinical parameters such as survival, body mass variation, leukogram, and blood bacterial count. Thus, TRPA1 could be a target for future therapeutic approaches in the treatment of intestinal mucositis.

Effects of dietary onion (Allium cepa) extract supplementation on performance, apparent total tract retention of nutrients, blood profile and meat quality of broiler chicks

Objective

This study was conducted to investigate the effect of dietary onion (Allium cepa) extract (OE) supplementation on growth performance, apparent total tract retention (ATTR), blood profile, carcass characteristics and meat quality in broilers.

Methods

Four hundred male broiler chicks (Ross 308, 3-d old) were randomly allocated to four dietary treatments for 28 d feeding trial. Each treatment has five replications with 20 birds each. Four dietary treatments were designated according to the OE supplementation levels (0 as control, 5, 7.5, and 10 g of OE per kg of basal diet respectively). On d 28, a total of 20 birds from each treatment were subjected for ATTR, serum biochemical assay, carcass characteristic and organ weight measurement.

Results

Overall weight gain of OE 7.5 g/kg group was higher (p = 0.04) than control group. The ATTRs of dietary energy (p<0.01) and ether extract (p = 0.04) linearly increased with increasing levels of dietary OE. However, no difference in ATTR of dry matter and crude protein was evident. Furthermore, serum IgG concentration increased linearly (p<0.01) and quadratically (p = 0.03) with increasing OE supplementation. No differences in carcass dressing weight and amount of abdominal fat by treatments were observed. Also, the weight of organ including immune organ was not different among the treatments. The TBARS values of 10 d stored breast meat decreased linearly (p<0.01) and quadratically (p<0.01) with increasing dietary OE levels. The meat color was also affected, with lower (p<0.01) redness score in meats from OE supplemented groups. This study showed that dietary OE improved broiler weight gain presumably by increasing feed intake and ATTR of both energy and ether extract. The dietary OE increased serum IgG level and meat anti-oxidation capacity.

Conclusion

This study implies that the recommended level of dietary OE supplementation could be beneficial for improving broiler performance and meat quality.

Effects of mannan oligosaccharide and <i>Curcuma xanthorrhiza</i> essential oil on the intestinal morphologyand stress indicators of broilers subjected to cyclic heat stress

Abstract. An experiment was carried out that was intended to explore the growth performance, nutrient retention, and heat stress biomarkers of finishing broilers under cyclic heat stress (HS) as modulated by the supplementation of mannan oligosaccharide (MOS) and Curcuma xanthorrhiza essential oil (CXEO). Two hundred and forty 21-day-old Ross 308 male broilers were allocated to four experimental treatments, each of which was replicated six times with 10 broilers per replicate. The diets included a control (CON), CON + 5 g of MOS kg−1, CON + 400 mg of CXEO kg−1 of feed, and CON + 5 g of MOS kg−1 + 400 mg of CXEO kg−1. From day 22 to 42, birds were subjected to cyclic HS by exposing them to 33 °C for 10 h (from 07:00 to 17:00 LT) and 22 °C from 17:00 to 07:00. Dietary treatments did not have an effect on average daily feed intake, feed conversion ratio, the duodenal histomorphology, and relative visceral weights. Body weight, average daily gain, villus length, crypt depth, and the villus-length-to-crypt-depth ratio in the jejunum were significantly increased in birds fed MOS or MOS + CXEO diets (p < 0.05). The relative bursa weight of the control birds was lower (p <  0.05) compared to those fed the MOS diet. Compared with CON, dietary treatments reduced corticosterone and creatine kinase levels, the heterophile-to-lymphocyte ratio, and mRNA levels of heat shock protein 70 in the breast muscle and jejunum (p < 0.05). It was concluded that dietary supplementation of either MOS or CXEO alone or in combination may reduce some of the harmful effects of HS in broiler chickens.

Impact of Cooking, Storage, and Reheating Conditions on the Formation of Cholesterol Oxidation Products in Pork Loin

This study investigates the effect of cooking, storage, and reheating conditions on the formation of cholesterol oxidation products (COPs) in pork loin. Samples of pork loin procured 24 h postmortem were initially processed and assessed for total fat and cholesterol content. The cooking methods evaluated were pan roasting, steaming, oven grilling, and microwaving. Cooked pork loin samples were stored at 4℃ and reheated after 3 and 6 d of storage using the original method of preparation or alternately, microwaving. Fat content increased significantly with cooking as a result of the loss in moisture but cholesterol content remained unchanged. Pan roasting and microwave cooking caused a significantly higher production of COPs, as with the process of reheating using microwave, pan roasting, and oven grilling methods. The major COPs found in pork loin were cholestanetriol, 20-hydroxycholesterol, and 25-hydroxycholesterol, whose concentrations varied according to the different cooking and reheating methods used. Moreover, the aerobic storage of cooked pork loin under a refrigerated condition also increased the formation of cholesterol oxides on reheating.

Proximate composition, cholesterol concentration and lipid oxidation of meat from chickens fed dietary spice addition (Allium sativum, Piper nigrum, Capsicum annuum)

The effects of supplementing spices, including garlic, black pepper and hot red pepper, in broiler chicken diet on proximate composition, cholesterol content and lipid oxidation of breast and thigh with drumstick meat, skin and liver were investigated. Meat proximate composition included measurements of moisture, protein, fat and ash content. Cholesterol content of tissue homogenates was performed by high-performance liquid chromatography–DAD analyses, while lipid oxidation of white and red meat, as well as liver, was expressed as a concentration of thiobarbituric acid reactive substances (TBARS) (mg malondialdehyde (MDA)/kg tissue). For biological research, eight treatments with a total of 1200 broiler chickens of hybrid line Hubbard were formed, with four replicates. In the control treatment, the chickens were fed with commercial mixtures of standard composition and quality based on corn flour and soybean meal. Experimental treatments were fed with the same commercial mixtures, except with addition of spices. At the end of the experiment and on the basis of gained results, it can be concluded that the chickens in experimental treatments with hot red pepper achieved statistically significantly (P < 0.05) higher final body masses (2460.6 and 2442.4 g) than did the chickens in the control and other treatments. Black pepper showed a positive and significant (P < 0.05) influence on improving the protein content in breast meat (24 g/100 g), hot red pepper lowered the cholesterol concentrations in meat (24.7 g/100 g in red meat), skin (87.4 g/100 g) and liver (263.1 g/100 g), while black pepper significantly (P < 0.05) reduced lipid oxidation in breast (0.05 mg MDA/kg tissue) and thigh with drumstick (0.12 mg MDA/kg tissue). On the basis of obtained findings, it can be concluded that the dietary spice herbs had a positive influence on a proximate composition of chicken meat, cholesterol concentrations and lipid oxidation process.

Phytogenic Administration and Reduction of Dietary Energy and Protein Levels Affects Growth Performance, Nutrient Digestibility and Antioxidant Status of Broilers

The aim of this study was to investigate the effect of reduced dietary energy (ME) and protein (CP) levels along with administration of a phytogenic feed additive (PFA) based on oregano, anise and citrus essential oils, on broiler growth performance, nutrient digestibility, meat and blood biochemical parameters and total antioxidant capacity (TAC). Depending on dietary ME and CP level down regulation compared to a corn-soybean meal basal diet A used as positive control, three diet types [A, B(=A-3%) and C(=A-6%)] were implemented. Depending on the inclusion or not of PFA at 125 mg/kg diet, 450 1-d old, male Cobb broilers were randomly allocated in six treatments according to a 3×2 factorial arrangement with 5 replicates of 15 broilers; A: diets formulated optimally to meet broiler nutrient requirements for maximizing protein content of meat for starter, grower and finisher growth periods; APh: A+PFA; B: suboptimal in ME and CP levels by 3%; BPh: B+PFA; C: suboptimal in ME and CP levels by 6%; CPh: C+PFA. Feed conversion ratio (FCR) was improved in birds fed diet A compared to diet C during the grower period (P _D =0.021) and overall (P _D =0.010). Phytogenic supplementation resulted in higher (P _D×Ph =0.020) total tract apparent digestibility of fat in birds fed diet C compared to diet A. Birds fed diet A had higher (P _D =0.001) plasma cholesterol, compared to birds fed diet C. In addition, birds fed diets A and B had higher (P _D =0.002) breast protein content compared to C. Overall, PFA inclusion reduced cholesterol (P _Ph =0.002) and increased plasma TAC (P _Ph <0.001). Moreover, PFA increased breast (P _Ph =0.001) and thigh (P _Ph =0.01) TAC. In conclusion, a reduction in dietary ME and CP levels, adversely affected the FCR, whereas PFA supplementation tended (P _Ph =0.089) to compensate these effects. Moreover, the addition of PFA reduced plasma cholesterol and improved plasma and meat TAC.

The Influence of Naringin or Hesperidin Dietary Supplementation on Broiler Meat Quality and Oxidative Stability

An experiment was conducted to examine the effects of supplementing broiler feed with hesperidin or naringin, on growth performance, carcass characteristics, breast meat quality and the oxidative stability of breast and thigh meat. Two hundred and forty 1-day-old Ross 308 broiler chickens were randomly assigned to 6 groups. One of the groups served as a control (C) and was given commercial basal diets, whereas the other five groups were given the same diets further supplemented with naringin at 0.75 g/kg (N1), naringin at 1.5 g/kg (N2), hesperidin at 0.75 g/kg (E1), hesperidin at 1.5 g/kg (E2) and a-tocopheryl acetate at 0.2 g/kg (E). At 42 days of age, 10 chickens per treatment group were slaughtered for meat quality and oxidative stability assessment. No significant differences were observed among groups in final body weight, carcass weight and internal organs weights (P>0.05) apart from liver that decreased linearly with increased levels of naringin (P-linear<0.05). Regarding the breast meat quality parameters, only redness (a*) value was higher in E1 and N1 group compared to VE group (P<0.05), while all the others i.e. shear values (N/mm²), pH₂₄, cooking loss (%) and L* and b* color parameters were not significantly different among groups (P>0.05). Measurement of lipid oxidation values showed that after hesperidin and naringin dietary supplementation, malondialdehyde values decreased in tissue samples in a dose depended manner (P-linear<0.05). In conclusion, hesperidin and naringin, positively influence meat antioxidative properties without negative implications on growth performance and meat quality characteristics in poultry, thus appearing as important additives for both the consumer and the industry.

Effect of dietary ethanol extracts of mango (Mangifera indica L.) on lipid oxidation and the color of chicken meat during frozen storage

The aim of this study was to evaluate the dietary effect of mango extracts on lipid stability and the coloring of broiler chicken breast meat during frozen storage. The treatments consisted of broiler chicken diet without antioxidants (control) and diets containing antioxidants: 200 ppm of butylated hydroxytoluene (BHT), 200 ppm of mango peel extract (MPE), 400 ppm of MPE, 200 ppm of mango seed extract (MSE), and 400 ppm of MSE. The broiler breasts were stored for 90 days and analysis of lipid oxidation and color was performed every 30 days. The thiobarbituric acid reactive substances values increased during storage and at 90 days, but the 400 ppm MSE treatment yielded lower values, indicating greater antioxidant activity. During storage, the lightness values decreased and the redness increased. Additions of 200 ppm BHT and 400 ppm MPE increased yellowness at 60 days of storage. Thus, mango peel and seed extracts added to broiler chicken diets reduce lipid oxidation and maintain color in breast meat during frozen storage, with mango seed extract at 400 ppm being the most effective.

Cooking, storage, and reheating effect on the formation of cholesterol oxidation products in processed meat products

BACKGROUND

Cholesterol is an important biological compound; however, its oxidation products have been proven to be harmful to human health. Cooking, storage, and reheating methods significantly affect the safety of meat products, as they contribute to the production of cholesterol oxidation products (COPs).

METHODS

Three cooking methods were used to cook sausages, loin ham, bacon, luncheon meat, and pressed ham, in order to investigate the effect of cooking, storage, and reheating on total cholesterol and on the formation of COPs. Cooked samples were stored at 4 °C and reheated after 3 and 6 storage days by the same cooking method or by microwaving. The samples were assessed for total lipids, cholesterol, and cholesterol oxides.

RESULTS

The average cholesterol content in the processed meat varied from 76.0 mg/100 g to 201.70 mg/100 g. Microwaved ham showed the lowest cholesterol content compared to that of other processed meat products. Significant differences were found in cholesterol content and cholesterol oxidation products depending on cooking, storage, and reheating methods. Six cholesterol oxides were found in processed meat, of which 7β-hydroxycholesterol and α-epoxides were detected as the major oxidation products.

CONCLUSIONS

Microwaving and oven grilling resulted in higher production of COPs in processed meat as compared with other cooking methods. Refrigerated storage tended to significantly increase the COPs content.

The effects of adding agrimony and sage extracts to water on blood biochemistry and meat quality of broiler chickens

The aim of our study was to determine the effects of supplementation of agrimony extract (Agrimonia eupatoria L.) and a combination of agrimony with sage extract (Salvia officinalis L.) to water during the fattening period of broiler chickens on selected biochemical and antioxidant indicators in blood, and on the nutritional composition and oxidative stability of meat. A total of 117 Cobb 500 chicks were randomly divided on the day of hatching into three groups (n = 39 in each) and fattened for 42 days. All groups were fed the same diets. In experimental group A water was supplemented with agrimony extract (0.2%). In experimental group AS water was supplemented with a combination of agrimony (0.1%) and sage (0.1%) extracts. Group C was control without supplementation. The total cholesterol, low density lipoproteins and malondialdehyde in serum were decreased (P < 0.05), dry matter and fat content in meat were increased (P < 0.05) in group A. The activity of superoxide dismutase in blood and the amount of thiobarbituric acid reactive substances in thigh meat on days 1 and 8 of storage under chilling conditions were lower (P < 0.05) in both experimental groups compared to control. Our results indicate that supplementation of agrimony and sage extract to water can beneficially influence the antioxidant status as well as oxidative stability of thigh meat and thus improve meat quality. This is a first similar study comparing addition of plant extracts to water in broiler nutrition.

Lipid stability, antioxidant potential and fatty acid composition of broilers breast meat as influenced by quercetin in combination with α-tocopherol enriched diets

Background

Dietary supplementation of antioxidants is a vital route to affect the oxidative stability and fatty acid profile of broiler meat. The supplementation of feed with antioxidants decreases degradation of lipids in muscles thereby enhances meat stability.

Methods

The present study was carried out to investigate the influence of dietary quercetin in combination with α-tocopherol on growth performance, antioxidant potential, lipid stability and fatty acid composition in breast meat of birds. Accordingly, one day old 300 Hubbard strain male broiler birds were given three levels of quercetin @100, 200 and 300 mg/kg feed in combination with α-tocopherol @150, 225 and 300 mg/kg feed. The resultant meat was subjected to antioxidant assay, lipid stability, quantification of antioxidants followed by fatty acid profile of broiler breast meat.

Results

The results explicated that feed treatments imparted momentous effect on gain in weight, and feed conversion efficiency however, intake of feed in birds affected non-momentously. The highest weight gain recorded in T9 as 2374.67 & 2388 g/bird followed by T8 & T6 2350 & 2353.33 and 2293.33 & 2307 g/bird, respectively whilst the lowest in T0 as 1992.67 & 1999 g/bird during the experimental year 2013 and 2014. The results regarding antioxidant potential revealed that among treatments, T9 exhibited highest values for total phenolic contents (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) & ferric reducing antioxidant power assay (FRAP) i.e. 158.70 ± 0.84 mg GAE/100 g, 82.40 ± 0.93 % and 682 ± 2.11 μmol/Fe^+2/g, respectively as compared to T0 104.27 ± 1.64 mg GAE/100 g, 54.71 ± 0.64 % and 542.67 ± 1.74 μmol/Fe⁺² /g of meat, correspondingly. The TBARS assay indicated that malondialdehydes production in meat increased during storage however, antioxidants deposition varied significantly among treatments. Fatty acid compositional analysis revealed that addition of quercetin with α-tocopherol in the bird’s diet decreased the fatty acid generation particularly saturated fatty acids.

Conclusion

Conclusively, dietary supplementation of quercetin along with α-tocopherol improves growth performance, antioxidant capacity, stability of lipids and fatty acid composition in breast meat of birds.

Effects of benzoic Acid and thymol on growth performance and gut characteristics of weaned piglets

A total of 144 weaned crossed pigs were used in a 42-d trial to explore the effects of different concentrations/combinations of benzoic acid and thymol on growth performance and gut characteristics in weaned pigs. Pigs were randomly allotted to 4 dietary treatments: i) control (C), basal diet, ii) C+1,000 mg/kg benzoic acid+100 mg/kg thymol (BT1), iii) C+1,000 mg/kg benzoic acid+200 mg/kg thymol (BT2) and, iv) C+2,000 mg/kg benzoic acid+100 mg/kg thymol (BT3). Relative to the control, pigs fed diet BT3 had lower diarrhoea score during the overall period (p<0.10) and improved feed to gain ratio between days 1 to 14 (p<0.05), which was accompanied by improved apparent total tract digestibility of ether extract, Ca and crude ash (p<0.05), and larger lipase, lactase and sucrose activities in the jejunum (p<0.05) at d 14 and d 42. Similarly, relative to the control, pigs fed diet BT3 had higher counts for Lactobacillus spp in digesta of ileum at d 14 (p<0.05), and pigs fed diets BT1, BT2, or BT3 also had higher counts of Bacillus spp in digesta of caecum at d 14 (p<0.05), and lower concentration of ammonia nitrogen in digesta of caecum at d 14 and d 42 (p<0.05). Finally, pigs fed diet BT3 had higher concentration of butyric acid in digesta of caecum at d 42 (p<0.05), and a larger villus height:crypt depth ratio in jejunum and ileum at d 14 (p<0.05) than pigs fed the control diet. In conclusion, piglets fed diet supplementation with different concentrations/combinations of benzoic acid and thymol could improve feed efficiency and diarrhoea, and improve gut microfloral composition. The combination of 2,000 mg/kg benzoic acid+100 mg/kg thymol produced better effects than other treatments in most measurements.

Effect of various levels of dietary curcumin on meat quality and antioxidant profile of breast muscle in broilers

The aim of this study was to determine the effects of curcumin on meat quality and antioxidant profile of breast muscle in broilers. In experiment 1, birds were fed basal diet with an additional 0, 50, 100, or 200 mg/kg curcumin, respectively. The results showed that dietary curcumin significantly increased the redness values of meat, catalase activity, and ABTS radical scavenging activity and decreased drip loss at 48 h. In experiment 2, birds reared under heat stress were assigned to similar treatments as experiment 1. Significant differences in the redox status of breast muscle were observed between the control and heat stress groups. The various levels of curcumin significantly prevented reactive oxygen species overproduction, enhanced the antioxidant defense system, and alleviated the abnormal change of antioxidant-related gene expression of muscle in heat-stressed birds. It was concluded that curcumin, as a potential antioxidant, improved meat quality and oxidant stability of muscle in broilers, whereas the inclusion of 50 and 100 mg/kg would be more efficient.

Production performance, meat composition and oxidative susceptibility in broiler chicken fed with different phenolic compounds

BACKGROUND

Various studies have been conducted to evaluate the effect of phenolic compounds on production animals. Supplementation of animal diets with phytogenic compounds, such as different essential oils and polyphenols, could improve animal productivity as well as the chemical composition and oxidative stability of food derived from those animals.

RESULTS

During the trial, 80 male broilers of the Ross 308 strain were allocated to four dietary groups: control and three groups supplemented with thymol, tannic acid and gallic acid. Feed utilisation was improved in all experimental groups and tannic acid also improved final body weight. Gallic acid significantly increased n-3 long-chain polyunsaturated fatty acids. A hypocholesterolaemic effect was noticed in all groups in liver, but not in muscle. The glucose lowering effect in serum was noticed in the tannic acid group in comparison to other experimental groups. Oxidative susceptibility was improved by tannic acid in liver and breast and by gallic acid in breast muscle.

CONCLUSION

The inclusion of phenolic compounds enhanced growth performance, decreased lipid oxidation, decreased cholesterol value and increased beneficial fatty acids content. Positive effects varied depending on phenolic compound used and, therefore, it would be interesting to further investigate synergistic effects of investigated phenolic compound.

Fly emergence from manure of Japanese quail fed thymol- or isoeugenol-supplemented diets

Many problems in poultry production are caused by a combination of interrelated factors such as management, stress, nutrition, and exposure to pathogens. Saprophagous flies that develop in poultry manure are a potential route of pathogen transmission. Besides being a nuisance, defecation and regurgitation of flies soil equipment and structures and can reduce light levels of lighting fixtures. These effects clearly affect management and may contribute to reductions in poultry egg production, health, and welfare. Many essential oils or their main components have bioactive effects such as natural repellents and insecticides, antioxidants, anticholesterolemics, and antimicrobials. This study evaluated if supplementing quail feed with thymol or isoeugenol as functional food could alter the production of flies from manure. Dropping samples deposited by quail fed with a supplementation of 2,000 mg of thymol or isoeugenol per kg of feed or no supplement (control) were collected. Each sample was incubated inside an emergence cage that was inspected daily to collect emerging adult flies. Fewer flies emerged from droppings of quail fed a thymol-supplemented diet (P = 0.01) and there was a tendency to a lower emergence from droppings of isoeugenol-fed quail (P = 0.09). The number of positive containers for Musca domestica was smaller from quail droppings of thymol- (P = 0.02) or isoeugenol- (P = 0.01) supplemented feed than from the control counterparts, suggesting an oviposition repellent effect. Supplementing quail feed with thymol or isoeugenol has an overall moderate effect against flies, reducing M. domestica emergence.

Gene expression of heat shock protein 70 and antioxidant enzymes, oxidative status, and meat oxidative stability of cyclically heat-challenged finishing broilers fed Origanum compactum and Curcuma xanthorrhiza essential oils

Heat stress in poultry is a serious problem in many countries and has been associated with oxidative stress. Hence, nutritional interventions with antioxidants might be beneficial. Therefore, the effects of dietary Curcuma xanthorrhiza (CX) and Origanum compactum (OC) essential oils on mRNA levels of heat shock protein 70 and antioxidant enzymes, oxidative status, and meat oxidative stability of heat-challenged broilers were studied. Starting on d 25 of age, a control diet and 4 diets containing 200 or 400 mg/kg feed of CX or OC (CX200, CX400, OC200, OC400 diets) were fed to 3 pen replicates of 20 Ross 308 chickens each. From d 28 of age on, the temperature was increased from 22 to 34°C with 50% RH for 5 h daily during 2 wk. Dietary CX or OC did not affect zootechnical performance. Feeding CX400 and both levels of OC increased the a* value in stored breast meat (P < 0.05), and OC diets tended to decrease the thiobarbituric acid reactive substances values in fresh breast meat (P = 0.061). Compared with control, at d 31, feeding CX400 and OC400 reduced mRNA levels of heat shock protein 70 and increased mRNA levels of catalase in kidney and liver (P < 0.05). The mRNA levels of superoxide dismutase were increased at d 31 on the OC400 diet in kidney and on the CX400 diet in heart (P < 0.05). In heart, at d 31, both dietary levels of CX and OC200 resulted in higher glutathione peroxidase activity (P < 0.05). Feeding CX400 increased superoxide dismutase activity in liver, kidney, and heart at d 31 (P < 0.05). Catalase activity was increased in the CX200 and OC400 groups at d 42 (P < 0.05). Feeding CX at both levels and OC200 decreased plasma malondialdehyde concentrations at d 42 (P < 0.05). In conclusion, dietary essential oils rich in simple phenolic compounds offer potential for improving the antioxidant defense against heat stress-induced changes.

Effects of dietary oleuropein supplementation on growth performance, serum lipid concentrations and lipid oxidation of Japanese quails

An in vivo experiment was conducted to compare the effects of dietary supplementation with oleuropein and/or α-tocopheryl acetate on growth performance, serum lipid concentrations and lipid oxidation of Japanese quail meat during refrigerated storage. Performance and slaughtering parameters were not affected by dietary treatments. The diets supplemented with oleuropein at the levels of 150 or 200 mg/kg were more effective in delaying lipid oxidation in breast and thigh meats compared with the control diet. The dietary inclusion of neither vitamin E nor oleuropein at different levels did not significantly affect the fatty acid compositions of the breast meat compared with the control diet. The diets supplemented with oleuropein at the levels of 150 or 200 mg/kg had significantly the highest polyunsaturated fatty acid and omega-3 fatty acid contents in thigh meat compared with the vitamin E diet. The ratio of omega-6 fatty acids to omega-3 FAs in thigh meat of quails fed diet supplemented with vitamin E at the level of 200 mg/kg was equivalent to those of quails fed the diets supplemented with oleuropein at the levels of 100 and 150 mg/kg. The results showed that the dietary oleuropein supplementation at 150 mg/kg level may be used in quail diets enriched with the polyunsaturated fatty acids of vitamin E as a natural antioxidant.