Broiler Breast Meat Research Articles

Effects of Pig Skin Collagen Supplementation on Broiler Breast Meat.

This study aimed to enhance the quality of broiler breast meat by adding pig skin collagen to feed. A total of 50 Ross 308 broilers were classified according to the following feeding regime for two weeks: basal diet (NC), basal diet+0.1% fish collagen (PC), basal diet+0.1% pig skin collagen (T1), basal diet+0.5% pig skin collagen (T2), and basal diet+1.0% pig skin collagen (T3). The moisture content was the highest in the PC group, and the protein content was the lowest in the T1 group (p<0.05). The fat content was higher in the T1 and PC groups, whereas the ash content was higher in the T3 group (p<0.05). Drip loss was the highest in the NC group and the lowest in the T2 group (p<0.05). Lightness was low in groups T2 and T3, redness was low in groups T2 and PC, and yellowness was low in groups T1, T2, and PC (p<0.05). The collagen content of the chicken breast was the highest in the T3 group, and that of the skin was the highest in the T1 group (p<0.05). The texture characteristics of springiness, cohesiveness, chewiness, and hardness were the highest in the T3 group (p<0.05). In conclusion, the supplementation of a broiler diet with pig skin collagen was found to increase the collagen content of the breast meat, indicating the improved quality of the broiler breast meat.

The Potential Impact of Moringa oleifera for Diminishing the Microbial Contamination and Prolonging the Quality and Shelf-Life of Chilled Meat

This study was implemented to assess the mechanism by which Moringa oleifera leaf extract (MOLE) improves the quality and prolongs shelf-life of the broilers’ breast meat. Ninety Cobb chicks were randomly allocated to 3 groups. A control group received the standard diet, whereas the other two groups received diets containing MOLE at the doses of 250 and 500 mg/kg for 21 days. Inclusion of MOLE in broilers diet significantly reduced the detrimental changes in the overall sensory attribute scores, characteristic color and odor, and the loss of breast muscle elasticity during storage. Furthermore, it significantly reduced concentrations of thiobarbituric acid, total volatile nitrogen, non-esterified fatty acids, and peroxide, during storage compared to the control samples. No effect on the concentrations of heavy metals, such as copper, cadmium, and lead, was observed. Decomposition of samples was delayed as indicated by lower pH values and higher sensory scores at 4 and 6 days of storage in the MOLE groups. Reduced contamination with E. coli and Salmonella species indicated an antibacterial effect of MOLE. Finally, the present study highlights that MOLE supplementation may play a role in improving quality and shelf-life of the chilled breast meat in broilers.

Effect of feeding of 10 % prefermented feed on fatty acid profile and oxidation changes in chicken breast meat

Abstract The aim of this work was to evaluate the effect of addition of 10 % fermented feed (FF) into commercial broiler feed on fatty acid profile, chemical composition and oxidative stability of chicken breast meat fat. FF was prepared by the process of fungal solid-state fermentation. Application of FF into the commercial feed mixtures resulted in increased content of gamma-linolenic and oleic acid in broiler breast meat (P &lt; 0.05). Oxidative stability of meat fat was significantly higher in experimental broilers group fed diet with the addition of 10% FF (P &lt; 0,05) after storage period of samples for seven days at temperature of 4 °C.

Evaluation of Cooking Time of Chicken Patties Prepared Using Woody Broiler Breast Meat

This study evaluated the cooking time of chicken patties prepared with broiler breast fillets exhibiting varying degrees of woody breast (WB). Intact breast fillets (<i>n</i> = 90) deboned at 3 h postmortem were collected from broilers processed following commercial-based operations and categorized based on the degree of tactile hardness in 3 WB categories (normal [NOR], mild [MIL], and moderate/severe [SEV]). These tactile scores were validated using the instrumental compression force analysis. Fillet color (<i>L</i>* , <i>a*</i>, and <i>b*</i>) and pH were also measured at 24 h postmortem. Breast fillets were individually ground and formed into patties (patties made with NOR [P-NOR], patties made with MIL [P-MIL], and patties made with SEV [P-SEV]). Patties were cooked from 2°C to a final center temperature of 75°C on a flat electric griddle (150°C). Internal patty temperatures were measured at 0, 1, 2, 3, and 4 min and then every 30 s until the target core temperature was reached. Cook loss and moisture content were also evaluated in cooked patties. SEV fillets showed higher (<i>P</i> &lt; 0.05) compression force, pH, <i>L*</i>, <i>a*</i>, and <i>b*</i> values than NOR fillets. The cooking time to the terminal point was lower for P-SEV compared with P-NOR (<i>P</i> &lt; 0.05). No differences were observed in cooking time between P-MIL and the other patty samples. Cook loss and moisture content levels were greater (<i>P</i> &lt; 0.05) in P-SEV in comparison with P-NOR and P-MIL. These results suggest that the WB condition can alter the thermal processing of chicken patties by reducing the cooking time. Further research would be needed to confirm potential alterations caused by this myopathy in thermophysical properties of intact WB fillets and further processed poultry products containing WB meat.

The physical change of broiler meat given shrimp peptide extract (SPE) in drinking water during room temperature storage (post mortem)

This study aims to determine the physical change of properties of broiler meat during storage at room temperature, This study used Schrimp Peptide Extract (SPE) in drinking water given to broiler who were 1 week old for 7 days in the morning. The research design used a completely randomized design with 4 SPE level treatments, T0 (0%), T1 (1%), T2 (2%), T3 (3%) in drinking water (v/v). Each treatment was repeated 5 times and each replication consisted of 12 animals randomly. The results showed that the treatment dose of Schrimp Peptide Extract (SPE) was significantly different (P &lt;0.05) on the water binding capacity, cooking loss, and tenderness, and not significantly different from the pH of the broiler breast meat.

육계 및 산란계 닭가슴살의 일반성분과 아미노산 조성 비교

This study aimed to compare the chemical and amino acid compositions of the breast meat of broiler and laying hens, which have low acceptance in the market. The breast meats were analyzed for the chemical and amino acid compositions of hydrolysates digested by protease at optimum reaction conditions using the amino acid analyzer. No significant differences in moisture and ash contents were detected between the two types of breast meat. However, there were significant differences in the crude lipid and protein contents of laying hen (1.01% and 23.68%, respectively) and broiler hen (1.54% and 25.41%, respectively) meat samples. The amino acid contents of the breast meat samples of the laying and broiler hens were as follows: aspartic acid (6.88% and 9.84%, respectively), leucine (2.01% and 2.99%, respectively), and arginine (0.97% and 1.32%, respectively). Furthermore, the broiler meat had higher contents of essential amino acids such as valine, methionine, isoleucine, leucine, and phenylalanine. The total essential amino acid contents of the two types of meat were 5.87% (laying) and 8.29% (broiler), while the branched chain amino acid contents were 2.97% (laying) and 4.60% (broiler). The result of this study suggests that the hydrolysate of broiler breast meat could possibly be utilized as functional ingredient for patient foods, elderly food, sports drink and condiment sources.

Effects of Protaetia brevitarsis seulensis powder dietary inclusion level on antioxidant activities of broiler breast meat during storage

AbstractThe present study aimed to evaluate the effects of Protaetia brevitarsis seulensis (PBS) powder dietary inclusion levels on the antioxidant activities of broiler breast meat during storage. A total of 270 Arbor Acres broiler chicks were randomly allocated to three treatments (3 replicates with 30 birds per pen), fed diets with inclusion of 0%, 0.5% or 1% PBS powder, in a completely randomized design. After slaughtering, samples were packed and stored at 4°C for later analysis of broiler breast meat. Antioxidant analysis included measurement of pH, thiobarbituric acid reactive substances (TBARS), and 1, 1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging activity. All samples were measured at storage days 0 and 7 as three replicates. For breast meat, changes were observed in pH, TBARS values, and DPPH radical scavenging at storage days 0 and 7 (p &lt; 0.05), except for TBARS values at storage day 0. Overall, the addition of PBS powder resulted in lower TBARS values and higher DPPH radical scavenging in broiler breast meat during storage. Based on these results, it can be concluded that the addition of 0.5% and 1% PBS powder to broiler diets was effective at reducing lipid oxidation during storage, which could be related to the subsequent lower meat pH.

사육 밀도가 육계 생산성, 면역 수준 및 계육 품질에 미치는 영향

The present experiment was conducted to evaluate the effect of stocking density on the growth performance, immune status, and meat quality of broilers. In total, 385 one-day-old Ross 308 broilers were randomly assigned to one of four distinct stocking densities: 26 birds/m², 22 birds/m², 19 birds/m², and 16 birds/m². They were fed the diet <i>ad libitum</i> for 5 weeks. Immunoglobulin (Ig) and corticosterone levels were evaluated, and growth performance, blood parameters, and breast meat quality were determined. It was observed that the weight gain and feed intake of growers (21~35 d) and broilers (0~35 d) were significantly reduced as the stocking density increased (<i>P</i>&lt;0.05). However, the feed intake of starters (0~21 d) significantly increased as the stocking density increased (<i>P</i>&lt;0.05). There were no significant differences in the biochemical profiles among the four different stock densities. Furthermore, no significant differences were observed in the stress parameters: (heterophils / lymphocytes ratio and corticosterone), IgA, and IgM; however, IgG significantly increased with stocking density (<i>P</i>&lt;0.05). The pH, water holding capacity, and cooking loss of the muscle were all unaffected by the stocking density, but the shear force (tenderness) increased slightly as the density increased. The findings of this study suggest that a lower stocking density (16 birds/m²) significantly improved the shear force of breast meat and IgG in broilers.

Investigation of breast meat traits of broilers fed different amounts of Hermetia illucens and Protaetia brevitarsis seulensis powder

AbstractThe aim of this study was to investigate the effects of different levels of Hermetia illucens (HI) and Protaetia brevitarsis seulensis (PBS) powder on breast meat of broilers during storage. A total of 400 1‐d‐old Arbor Acres broilers were randomly divided into four treatments; each treatment group included four replicate pens with 25 birds per pen. Broilers were fed basal diets supplemented with 0.5%, and 1% HI powder or 1.5% PBS powder or only basal diets without HI or PBS. Traits such as meat quality, color, and antioxidant effects were evaluated. The different levels of HI and PBS powder did not enhance meat quality and color during storage. On day 0, thiobarbituric acid reactive substance (TBARS) values were not significantly affected by different levels of HI and PBS (p &gt; 0.05). However, a significant decrease in TBARS values on day 7 was observed with 0.5% HI and 1.5% PBS treatment compared to values obtained with other treatments (p &lt; 0.05). The reduction in TBARS values with 0.5%, and 1% HI or 1.5% PBS treatments on day 7 was 75.4%, 63.1% and 76.9%, respectively. Between the different levels of HI and PBS treatment, no significant differences in 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging were observed after 7 days of storage. However, addition of HI and PBS powder to broiler diets had a significant effect (p &lt; 0.05) on DPPH radical scavenging in broiler breast meat on day 0. These results indicate that addition of 0.5% HI and 1.5% PBS to broiler diets improves the antioxidant activity of broiler breast meat during storage.

Effect of age and different doses of dietary vitamin E on breast meat qualitative characteristics of finishing broilers.

The supplementation of vitamin E on broiler chicken diets is essential to the prevention of lipid oxidation reactions in the meat and improvement of meat quality. The objective of this study was to assess the effect of different doses of dietary vitamin E on breast meat quality of broiler chickens in the finishing period. Five doses of vitamin E were used (30, 90, 150, 210, and 270 mg/kg feed) in broilers' diets from 42 to 54 d of age. A completely randomized design was conducted, followed by a split-plot, where the vitamin E dose was considered as the whole plot, and broilers’ age at slaughter was the subplot. Breast meat quality was assessed at 4 different ages (45, 48, 51, and 54 d old), using 50 birds per age, totaling 200 birds. Meat quality characteristics evaluated were: pH at 24 h post mortem, color (brightness, redness, and yellowness), water holding capacity, cooking loss, shear force, and lipid peroxidation. There was no interaction between age and dose of vitamin E for meat quality characteristics (P > 0.05). The age at slaughter had a quadratic effect (P < 0.05) on pH, brightness, redness, and water holding capacity. Although pH values were higher in the breast meat of older birds (51 and 52 d old), breast meat of younger birds (48 d) had a more reddish aspect. Shear force value was higher in breast meat of birds slaughtered at later ages (P < 0.01), as a linear age-effect was observed. Brightness increased linearly (P < 0.05) with higher vitamin doses, whereas treatments did not alter yellowness, cooking loss, and lipid peroxidation. In this study, increasing vitamin E doses in the finishing period increased the brightness of broiler breast meat, whereas slaughtering at later ages resulted in greater meat pH and shear force value.

Nutritional Properties and Oxidative Indices of Broiler Breast Meat Affected by Wooden Breast Abnormality.

Simple SummaryChicken breast is considered as a good source of high-quality protein and essential trace minerals. However, the nutritive quality of the meat can be adversely affected by wooden breast (WB) myopathy. WB manifests as decreased contents of total protein (per gram of meat) and essential amino acids isoleucine, leucine and valine. In addition, the mineral profile of WB meat is abnormal. The cause of WB remains unclear, but it has been linked with oxidative stress within the breast muscle in the living birds. In this study, protein oxidation in the meat and changes in absolute expression of oxidative stress response genes were identified, strengthening the link between oxidative stress and the incidence of WB.Wooden breast (WB) abnormality adversely impacts the quality of chicken meat and has been linked with oxidative stress. In this study, breast samples were taken from carcasses of 7-week-old Ross 308 broilers 20-min and 24-h postmortem. Five WB and seven non-WB control samples were assigned based on palpatory hardness (non-WB = no unusual characteristics and WB = focal or diffused hardness). WB exhibited lower contents of protein and the amino acids, i.e., isoleucine, leucine and valine, lighter surface color, lower shear force, greater drip loss and altered mineral profiles (p ≤ 0.05). Despite no difference in lipid oxidation, a greater degree of protein oxidation was found in the WB meat (p ≤ 0.05). Absolute transcript abundances of superoxide dismutase, hypoxia inducible factor 1 alpha and pyruvate dehydrogenase kinase 1 were greater in WB (p ≤ 0.05), whereas lactate dehydrogenase A expression was lower in WB (p ≤ 0.05). The findings support an association between oxidative stress and the altered nutritional and technological properties of chicken meat in WB.

Effect of pomegranate (Punica granatum L) peel powder meal dietary supplementation on antioxidant status and quality of breast meat in broilers

This study examined the antioxidant status and quality of breast meat in broiler birds fed diets supplemented with pomegranate peel powder meal (PPPM). During the 35-d feeding trial, broiler birds were fed six experimental diets: diet with 0% additives (negative control; NEGCON); diet with α-Tocopherol acetate at 200 g/tonne (positive control; POSCON); and four levels (2, 4, 6 and 8 g/kg) of PPPM, designated as PPPM2, PPPM4, PPPM6, and PPPM8. Breast muscle pH was determined 15mins and 24hrs postmortem. The breast muscles were then stored at 4 °C to determine shelf-life attributes (pH, colour, hue angle, and chroma) for 16 days. Meat from the 8 g/kg PPPM had the highest thawing loss, whereas cooking loss was lowest at 2 g/kg PPPM inclusion. The meat of birds fed 2 g/kg and 4 g/kg PPPM had the highest (P<0.05) ability to scavenge the ABTS [(2, 2-azinobis (3ethylbenzothiazoline-6 sulfonic acid))] radical cation (ABTS+), whereas, catalase activity was increased at 8 g/kg PPPM. The results obtained in this study indicate that 2 g/kg supplementation of pomegranate peel powder meal significantly improved the water-binding capacity of broiler breast meat, owing to the reduced cooking loss of the meat, and meat from the PPPM2 (2 g/kg) group had the highest ability to scavenge ABTS.

Physical quality characteristics of breast and leg meat of slow- and fast-growing broilers raised in different housing systems.

This study was made to determine the effects of genotype and housing system on physical quality characteristics of breast and leg meat of broilers under experimental conditions. The 150 slow-growing and 150 fast-growing 1 d old chicks were divided into three sub-groups with indoor raised slatted plastic floor, indoor concrete floor with rice hull litter, and free-range housing systems (2 genotype groups 3 housing systems). All birds were offered the same diet and were housed in similar conditions until they were 56 d old. At slaughter, 10 birds from each main group were selected randomly to determine the quality characteristics of the meat. In total, 60 breast meat pieces (pectoralis major muscle) and 60 legs of the chickens were used for meat quality analysis including pH, shear force, and colour characteristics such as lightness (), redness (), yellowness (), saturation (), and hue angle (). The pH of breast meat was significantly affected by genotype and housing system ( and ). There were significant genotype housing system interactions for pH ( and ) and shear force values ( and ) of leg and breast meat. There were no significant effects of genotype and housing system on leg and breast meat colour properties except for effects of genotype on redness () of breast meat () and effects of housing on redness of leg meat colour (). Slow-growing chickens and chickens housed in deep litter had a higher redness (darker) value of breast and leg meat colour compared to fast-growing birds and free range and slatted floor. In conclusion, it can be said that fast-growing broilers may be more appropriate for slatted plastic floor housing and slow-growing broilers may be more suitable for a free-range housing system, but further research on factors affecting meat quality would be very beneficial, especially in slow-growing broilers.

Research Note: Comparison of 3 methods used for estimating cook loss in broiler breast meat

The objective of this study was to evaluate different methods used for estimating cook loss in broiler breast fillets (pectoralis major). Two experiments were conducted. In the first experiment, intact fillets were weighed, cooked to 75°C, and then subjected to 1 of 3 postcook handling treatments: cooling for 5 min at room temperature before reweighing (5-minute), cooling at room temperature until they reached room temperature before reweighing (RT), or cooling in ice water until they reached room temperature before reweighing (IW). In the second experiment, breast fillet portions were used to compare the effects of endpoint temperature (53°C, 57°C, 68°C, 75°C, or 90°C) on cook loss estimation by the 5-minute and RT methods. Breast fillets were collected from local chicken processing plants and trimmed to similar weight prior to cooking. Cook loss, cook loss retention, and total cook loss after 24 h in cooked fillets were measured for comparisons. Data showed that cook loss (<17%) and total loss (19.3%) estimated with the IW method were lower (P < 0.05) than those with the 5-minute and RT methods (19–21% for cook loss and 21.1–21.3% for total loss), which did not differ from each other. When the endpoint temperature was ≥75°C, no differences in cook loss estimates or moisture loss were noted between the 5 min and RT methods (after 3 h cooling). However, when the temperatures were 53°C to 75°C, cook loss estimations were significantly different (P < 0.05) between the 5 min and RT methods (more than 4%). Reduced endpoint temperature resulted in increasing differences (from less than 5% to more than 9%) in cook loss estimates. These results demonstrate that endpoint cooking temperature and postcooking sample handling methods may affect cook loss estimates in broiler breast meat.

Quality Differences in Traditional and Clean Label Chicken Patties Formulated with Woody Breast Meat

Wooden breast (WB) is a myopathy that affects the pectoralis major of broilers and negatively affects broiler breast meat quality, yields, and profits. Therefore, the objective of this research was to evaluate quality differences between chicken patties that differed in the percentage of normal (% NOR) and severe (SEV) breast meat: 0% NOR, 33% NOR, 67% NOR, and 100% NOR. Patties were formulated with a control (salt), traditional (salt, sodium phosphate), or clean label (salt, potassium carbonate) marinade. A 3 × 4 factorial structure within a randomized complete block design with 3 replications was used to evaluate the effects of marinade (control, traditional, and clean label) and % NOR (0% NOR, 33% NOR, 67% NOR, and 100% NOR) on product quality. The 100% NOR patties had greater cook yields than 33% NOR and 0% NOR patties (P 6). Use of sodium phosphate increased protein bind and cook yields at all % NOR. Quality differences were still detectable in patties formulated with 67% or more WB, which will continue to cause yield losses and decreased quality in processed poultry products. However, if these yields and protein functionality deficiencies are acceptable to processors, it would be feasible to use either 33% or 67% SEV WB in the formulation of ground patties.

Expressible fluid measurements of broiler breast meat affected by emerging muscle abnormalities

Effects of emerging myopathies, spaghetti meat (SM), wooden breast (WB), and white striping/WB (WS/WB), on meat water-holding capacity (WHC) were investigated using expressible fluid (EF). Broiler breast meat (Pectoralis major) was collected from a commercial plant and sorted into normal (NORM), SM, WB, and WS/WB categories. The filter paper method was used to measure EF of fresh, frozen, and cooked meat samples with myopathies. Ratios of the total wet area over meat area were used to estimate EF. There were no differences in EF ratios between NORM and bone (dorsal) side of WB and WS/WB meat regardless of raw meat state and between NORM and SM meat regardless of SM location and meat state. There were no differences in EF ratios between NORM, SM, WB, WS/WB for cooked meat except for the samples from discolored area of cooked WB and WS/WB meat. Meat from skin (ventral) side of raw WB and WS/WB showed greater (P < 0.05) EF values (>4.01) than that of NORM (<3.30). The EF values (<3.89) from discolored area of cooked WB and WS/WB were lower than that of NORM (5.01). Effects of myopathies on EF/WHC vary with locations in abnormal broiler Pectoralis major.

Broiler responses to ferrous sulfate at different time periods: a comprehensive research on qualitative parameters of breast meat.

The objective of present study was to study the effects of dietary ferrous sulfate (FeSO4) and time periods on Fe deposition, nutrients composition, color indices, water-holding capacity and oxidative stability of breast meat in broilers. This experiment was performed by 450 broilers in a 3 × 3 factorial design with 3 levels of supplemental Fe (0, 40 and 80mg/kg) and 3 time periods (total, T: from 1 to 42days; grower and finisher, GF: from 11 to 42days and finisher, F: from 25 to 42days). The results showed that increasing the iron supplementation to 80mg/kg increased the breast meat crude Protein. Adding 80mg/kg of FeSO4 during the T period increased the iron content of breast meat compared to other dietary periods. Supplementation of 40mg/kg FeSO4 during T and GF periods increased quadratically (P < 0.001) the L* value of meat compared to F period. Meat redness significantly increased by adding of 80mg/kg iron into broiler diet. At 1 and 7day postmortem, malondialdehyde (MDA) and total antioxidant capacity (T-AOC) of meat were measured for determination of lipid oxidation stability of tissue. Feeding 40mg/kg Fe caused a higher MDA value at both time points compared to 0mg/kg Fe (linear response). However, increasing the Fe level to 80mg/kg decreased MDA of meat (quadratic response). Adding 40mg/kg Fe increased T-AOC of meat at both time points. It was concluded that dietary supplementation of 80mg/kg Fe during T period resulted in the higher Fe deposition and better oxidative stability of breast meat in broilers.

Biorefined grass-clover protein composition and effect on organic broiler performance and meat fatty acid profile.

Protein extracted from green biomass can be a sustainable and valuable feed component for organic poultry production. Earlier studies in rats have shown high digestibility of laboratory-scale extracted protein. The aim of this study was to test the effect of upscaling the biorefining process on composition of protein extracted from organic grass-clover and on performance of organic broilers when including grass-clover in the feed. Crude protein content of the extracted grass-clover protein was 36.2% of dry matter (DM) with a higher methionine content, but lower lysine and total sulphur-containing amino acids than that in soybean. Acid-insoluble residue constituted a major fraction of the dietary fibre content, and a large proportion of total CP was bound in this fraction. Alpha-linolenic acid was the dominating fatty acid in the extracted grass-clover protein. One-day-old organic Colour Yield broiler chicks were included in a dose-response trial with grass-clover protein constituting 0%, 8%, 16% or 24% of the feed from day 12 and until slaughter at day 57. Increasing levels of grass-clover protein extract reduced feed intake, growth and slaughter weight; however, at 8% inclusion feed intake and performance were not affected. The fatty acid composition in broiler breast meat reflected the composition of grass-clover protein extract; thus, the increasing dietary addition increased meat alpha-linolenic acid content. A lowered tocopherol content in meat from broilers fed increasing grass-clover protein demonstrated the need for increased amounts of antioxidants due to the high content of unsaturated fat. In conclusion, the study shows that broilers can grow on grass-clover protein from an upscaled biorefining process, but highlights the importance of further optimisation with focus on increased protein content and on avoiding formation of insoluble protein complexes, as these most likely reduce protein digestibility.

Transcriptional Profiles of Skeletal Muscle Associated With Increasing Severity of White Striping in Commercial Broilers.

Development of the white striping (WS) abnormality adversely impacts overall quality of broiler breast meat. Its etiology remains unclear. This study aimed at exploring transcriptional profiles of broiler skeletal muscles exhibiting different WS severity to elucidate molecular mechanisms underlying the development and progression of WS. Total RNA was isolated from pectoralis major of male 7-week-old Ross 308 broilers. The samples were classified as mild (n = 6), moderate (n = 6), or severe (n = 4), based on number and thickness of the white striations on the meat surface. The transcriptome was profiled using a chicken gene expression microarray with one-color hybridization technique. Gene expression patterns of each WS severity level were compared against each other; hence, there were three comparisons: moderate vs. mild (C1), severe vs. moderate (C2), and severe vs. mild (C3). Differentially expressed genes (DEGs) were identified using the combined criteria of false discovery rate ≤ 0.05 and absolute fold change ≥1.2. Differential expression of 91, 136, and 294 transcripts were identified in C1, C2, and C3, respectively. There were no DEGs in common among the three comparisons. Based on pathway analysis, the enriched pathways of C1 were related with impaired homeostasis of macronutrients and small biochemical molecules with disrupted Ca2+-related pathways. Decreased abundance of the period circadian regulator suggested the shifted circadian phase when moderate WS developed. The enriched pathways uniquely obtained in C2 were RNA degradation, Ras signaling, cellular senescence, axon guidance, and salivary secretion. The DEGs identified in those pathways might play crucial roles in regulating cellular ion balances and cell-cycle arrest. In C3, the pathways responsible for phosphatidylinositol 3-kinase-Akt signaling, p53 activation, apoptosis, and hypoxia-induced processes were modified. Additionally, pathways associated with a variety of diseases with the DEGs involved in regulation of [Ca2+], collagen formation, microtubule-based motor, and immune response were identified. Eight pathways were common to all three comparisons (i.e., calcium signaling, Ras-associated protein 1 signaling, ubiquitin-mediated proteolysis, vascular smooth muscle contraction, oxytocin signaling, and pathway in cancer). The current findings support the role of intracellular ion imbalance, particularly Ca2+, oxidative stress, and impaired programmed cell death on WS progression.

Ethanolic extract of mango seed used in the feeding of broilers: effects on phenolic compounds, antioxidant activity, and meat quality

The objective of this study was to evaluate the effect of including different levels of ethanolic extract of mango seed (EEMS) in broiler chicken rations on their phenolic compound levels, antioxidant activity, and meat quality. Initially, 756 one-day-old male chicks of the Ross 308 line were distributed in a completely randomized experimental design with seven treatments and six replicates of 18 birds. The treatments consisted of (i) a ration without the addition of antioxidants, (ii) a ration with the addition of 200 ppm of the antioxidant butylated hydroxytoluene (BHT), and (iii) a ration with the addition of 200, 400, 600, 800, or 1000 ppm of EEMS. According to the results, the values of phenolic compounds, the lipid stability of meat (measured by the value of thiobarbituric acid reactive substances), shear force, loss of cooking water, color, and pH of the meat differed significantly between the treatments. For the antioxidant activity of the meat, there was no significant difference between the treatments by the 2,2-diphenyl-1-picrylhydrazyl method; however, by the 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) method, the breast meat of broilers fed diets containing EEMS from 600 ppm and up presented higher antioxidant capacity when compared with the meat of the birds fed the control diet. In the ABTS method, there was no significant difference between the use of synthetic antioxidant BHT and the addition of EEMS at different levels. In conclusion, the addition of EEMS does not affect meat quality parameters of broilers, but when a dose of 600 ppm or more is added, the antioxidant capacity of meat measured by the ABTS method increases.