Poultry Meat Quality Research Articles

Identification of genomic regions and candidate genes for chicken meat ultimate pH by combined detection of selection signatures and QTL

BackgroundThe understanding of the biological determinism of meat ultimate pH, which is strongly related to muscle glycogen content, is a key point for the control of muscle integrity and meat quality in poultry. In the present study, we took advantage of a unique model of two broiler lines divergently selected for the ultimate pH of the pectoralis major muscle (PM-pHu) in order to decipher the genetic control of this trait. Two complementary approaches were used: detection of selection signatures generated during the first five generations and genome-wide association study for PM-pHu and Sartorius muscle pHu (SART-pHu) at the sixth generation of selection.ResultsSixty-three genomic regions showed significant signatures of positive selection. Out of the 10 most significant regions (detected by HapFLK or FLK method with a p-value below 1e-6), 4 were detected as soon as the first generation (G1) and were recovered at each of the four following ones (G2-G5). Another four corresponded to a later onset of selection as they were detected only at G5. In total, 33 SNPs, located in 24 QTL regions, were significantly associated with PM-pHu. For SART-pHu, we detected 18 SNPs located in 10 different regions. These results confirmed a polygenic determinism for these traits and highlighted two major QTL: one for PM-pHu on GGA1 (with a Bayes Factor (BF) of 300) and one for SART-pHu on GGA4 (with a BF of 257). Although selection signatures were enriched in QTL for PM-pHu, several QTL with strong effect haven’t yet responded to selection, suggesting that the divergence between lines might be further increased.ConclusionsA few regions of major interest with significant selection signatures and/or strong association with PM-pHu or SART-pHu were evidenced for the first time in chicken. Their gene content suggests several candidates associated with diseases of glycogen storage in humans. The impact of these candidate genes on meat quality and muscle integrity should be further investigated in chicken.

Nitrites on sensory quality of poultry meat cooked hams

At the present time, the use of nitrites and nitrates are technologically necessary in maintaining flavor, color and texture characteristics associated with and expected of certain stable food items. The effect of nitrite on sensory quality of poultry meat cooked hams was determined. Cooked hams prepared from chicken breast plus 15% brine solution. Four different batters ( A, B, C and D) with 0, 50, 100 and 200 ppm nitrite were made. The samples were cooked in a water bath at 68 °C, then cooled by showering with cold water and stored in 4°C for 8 weeks. The data clearly demonstrated that the nitrite concentration had not influenced in aerobic and lactic acid bacteria counts in the first day after production whilst, there were some unmatchable variations at 8th week of analysis. The residual nitrite contents, the 1st day after production, were 50% of initial amount added. The decrease of nitrite concentration reached 75% at the end of the storage. The addition of 50 and 100 ppm sodium nitrite improved drastically the hue of the surface color whilst, 200 ppm content decreased the a* value (intense of red color) of the samples. Panelists judged Β and C samples better than A and D.

Влияние озоно-воздушной смеси на качество и сроки хранения мяса молодняка перепелов

Промышленная технология содержания птиц способствует понижению естественной резистентности, продуктивности, возникновению различных патологических состояний организма и нередко понижению качества мяса птицы. Научно-хозяйственный опыт выполнен в октябре – декабре 2016 г. на птицеферме Чувашии. Материалом для исследования служило мясо перепелов 60-дневного возраста, образцы которого отбирали строго по методу аналогов. Изучено влияние озоно-воздушной смеси на качество и сроки хранения мяса молодняка перепелов с использованием отечественного озонатора «Pozitron-3 Air 1». В 1-й серии опытов тушки мяса перепелят обрабатывали озоно-воздушной смесью с дозой 5 мг/м3 с экпозицией 4 ч в течение 3 дней, во 2-й серии опытов — в дозе 10 мг/м3 4 ч в течение 4 дней. Показано, что озоно-воздушная смесь оказывает позитивное воздействие на сроки хранения и качественные показатели мяса молодняка перепелов. Так, после обработки проб мяса озоно-воздушной смесью в дозе 10 мг/м3 с экспозицией 4 ч мясо перепелят имело специфический запах, характерный свежему мясу, мясной бульон — прозрачный и ароматный; консистенция мышц — плотная, при надавливании пальцем образующаяся ямка быстро выравнивалась. При этом реакция на периоксидазу была положительная, с сернокислой медью — отрицательная, pH мяса колебался на уровне 5,82 – 5,87, концентрация аминоаммиачного азота варьировала в пределах 1,24 – 1,26 мг. При микроскопии мазков-отпечатков с глубоких слоев мышц выделены единичные палочки и кокки. Обработка озоно-воздушной смесью способствовала достоверному удлинению срока хранения мяса в опытных пробах по сравнению с контрольными аналогами в среднем на 18,88 суток (P < 0,01).

THE SCIENTIFIC APPROACH OF DETERMINATION POULTRY GRADE AND POULTRY PRODUCTS

There was proposed the system of classification of poultry by grades, taking into account the rate of individual bone-in and boneless pieces, and minced meat according to objective quality indexes, namely the ratio of the mass fraction of fat and mass fraction of protein in terms of protein quality (ratio of tryptophan to hydroxyproline), the ratio of the energy value and other indicators established for land and water-floating bird and is comparable to similar measures for beef and pork. Was given the quantitative criteria for rating the quality of poultry meat for content of muscle, connective and fatty tissues (skin with fat) in gutted carcass and its parts, installed there output and factors consumer value (FCV). Also was given the comparative rate of biological value of raw meat of slaughter animals and poultry, poultry meat mechanically deboning and nutritional supplements of animal and vegetable origin. It is established, that poultry meat mechanically separated on the functional-technological properties and bioavailability significantly superior to animal and vegetable proteins. The biological value of the lump meat of chickens-broilers and hens egg directions 1 grade has values 73.12 and 72.92%, the same time the biological value of goose meat from deboning carcasses of 2 and 1 grades has high values and varies from 79.77 to 81.14%. The new approach of the definition types of meat poultry and poultry products increases the range of foods allowed by the introduction in the recipe of sausage stuffing alternative sources of raw materials of animal and vegetable origin, adequate and balanced protein composition that is a definite contribution to the solution of the problem of providing the population with goods of high quality and enhance production efficiency.

Integrated Analysis of MiRNA and Genes Associated with Meat Quality Reveals that Gga-MiR-140-5p Affects Intramuscular Fat Deposition in Chickens

Background/Aims: Poultry meat quality is affected by many factors, among which intramuscular fat (IMF) is predominant. IMF content affects the tenderness, juiciness, and favor of chicken. An increasing number of studies are focusing on the functions of microRNAs (miRNAs) during the adipogenic process. However, little is known about miRNAs associated with poultry IMF deposition, especially intramuscular adipocyte differentiation. Methods: The IMF content of two physiological stages was measured, and miRNA-Seq and RNA-Seq data were integrated and analyzed. A chicken intramuscular adipocyte cell differentiation model was constructed. A luciferase reporter assay, miRNA overexpression, and Oil Red O staining were used to confirm the targets of gga-miR-140-5p. Results: Our results showed that late-laying-period hens, which had a higher IMF content, exhibited lower global expression levels of miRNAs than juvenile hens. A total of 104 differentially expressed (DE) miRNAs were identified between the two groups. Integrated analysis of differentially expressed genes and DE miRNAs identified a total of 378 miRNA-mRNA pairs. Functional enrichment analysis revealed that these intersecting genes are involved in ubiquitin-mediated proteolysis, the peroxisome proliferator-activated receptor signaling pathway, glycerophospholipid metabolism, and fatty acid elongation and degradation pathways. Furthermore, we demonstrated that gga-miR-140-5p promoted intramuscular adipocyte differentiation via targeting retinoid X receptor gamma. Conclusion: Our findings may contribute to a more thorough understanding of chicken IMF deposition and the improvement of poultry meat quality.

ОСОБЛИВОСТІ РОЗРОБКИ РЕКЛАМНОГО КРЕАТИВУ ДЛЯ ПРОСУВАННЯ ПРОДУКЦІЇ ПТАХІВНИЦТВА

The article presents the results of a study of the peculiarities of the formation of advertising creativity in the poultry industry, reveals the essence of the concept of "advertising creative", analyzes the advertising campaigns of the industry leader – TM "Nasha Ryaba", defined the basic techniques, technologies, methods and factors for the development of an effective advertising creative for promoting the products of the poultry branch. According to the research, creative in advertising is the use of creative ideas and technologies to achieve the entrepreneurial goals of advertising, which impose certain restrictions on advertising creativity, directing it to the transmission of specific information. When developing an advertising creative to promote poultry products, it is advisable to appeal to perceptions and feelings and stimulate trial purchases. The main factors that need to be taken into account to increase the effectiveness of advertising communications of producers of eggs and poultry meat: the creative should reflect the difference between the advertised product and competitors' products, including due to its special quality parameters; it is important to show the convenience of product use, its freshness, usefulness, variety, high taste characteristics, unique production technologies; you need to communicate with your consumers by setting up a sale through network resources; if the product is a local manufacturer, then the consumer should be able to understand this; products in advertising creative should look attractive, appetizing, encourage approbation by their appearance, color, packaging, stimulating sensory sensations; the consumer should be aware of the company's environmental and social responsibility. When developing an advertising creative for promoting poultry products, traditional methods are acceptable: hyperbole, comparison, metonymy, associations, the focal objects method, synectics, and the like. A characteristic feature of the creative name in the poultry industry is the corresponding association with the product. Advertising campaigns of PJSC "Myronivsky Hliboproduct" reflect most of the factors of successful advertising creativity. They not only actively promote a specific brand of poultry meat, but often have other, more global goals - product propaganda, competitive confrontation, and the fight against prejudices regarding the quality of poultry meat grown in industrial conditions.

Determinants of broiler chicken meat quality and factors affecting them: a review.

Broiler production at mass level has already been achieved and now emphasis is being laid on increasing meat quality by altering various characteristics of broiler meat. Appearance, texture, juiciness, wateriness, firmness, tenderness, odor and flavor are the most important and perceptible meat features that influence the initial and final quality judgment by consumers before and after purchasing a meat product. The quantifiable properties of meat such as water holding capacity, shear force, drip loss, cook loss, pH, shelf life, collagen content, protein solubility, cohesiveness, and fat binding capacity are indispensable for processors involved in the manufacture of value added meat products. Nutrition of birds has a significant impact on poultry meat quality and safety. It is well known that dietary fatty acid profiles are reflected in tissue fatty acid. Management of poultry meat production is reflected mostly on consumption features (juiciness, tenderness, flavour) of meat. After slaughter, biochemical changes, causing the conversion of muscle to meat, determine final meat quality. Postmortem carcass temperature has profound effect on rigor mortis and the physicochemical changes observed in PSE muscles are attributed to postmortem glycolysis, temperature, and pH. Primary processing and further processing have become a matter of concern with respect to nutritional quality of broiler meat. Genetic variation among birds could contribute to large differences in the rate of rigor mortis completion and meat quality. Heritability estimates for meat quality traits in broilers are amazingly high (0.35-0.81), making genetic selection a best tool for improvement of broiler meat quality.

Oxidative and glycolytic skeletal muscles show marked differences in gene expression profile in Chinese Qingyuan partridge chickens.

Oxidative and glycolytic myofibers have different structures and metabolic characteristics and their ratios are important in determining poultry meat quality. However, the molecular mechanisms underlying their differences are unclear. In this study, global gene expression profiling was conducted in oxidative skeletal muscle (obtained from the soleus, or SOL) and glycolytic skeletal muscle (obtained from the extensor digitorum longus, or EDL) of Chinese Qingyuan partridge chickens, using the Agilent Chicken Gene Expression Chip. A total of 1224 genes with at least 2-fold differences were identified (P < 0.05), of which 654 were upregulated and 570 were downregulated in SOL. GO, KEGG pathway, and co-expressed gene network analyses suggested that PRKAG3, ATP2A2, and PPARGC1A might play important roles in myofiber composition. The function of PPARGC1A gene was further validated. PPARGC1A mRNA expression levels were higher in SOL than in EDL muscles throughout the early postnatal development stages. In myoblast cells, shRNA knockdown of PPARGC1A significantly inhibited some muscle development and transition-related genes, including PPP3CA, MEF2C, and SM (P < 0.01 or P < 0.05), and significantly upregulated the expression of FWM (P < 0.05). Our study demonstrates strong transcriptome differences between oxidative and glycolytic myofibers, and the results suggest that PPARGC1A is a key gene involved in chicken myofiber composition and transition.

Proteomic analysis reveals changes in carbohydrate and protein metabolism associated with broiler breast myopathy

White Striping (WS) and Woody Breast (WB) are 2 conditions that adversely affect consumer acceptance as well as quality of poultry meat and meat products. Both WS and WB are characterized with degenerative myopathic changes. Previous studies showed that WS and WB in broiler fillets could result in higher ultimate pH, increased drip loss, and decreased marinade uptake. The main objective of the present study was to compare the proteomic profiles of muscle tissue (n = 5 per group) with either NORM (no or few minor myopathic lesions) or SEV (with severe myopathic changes). Proteins were extracted from these samples and analyzed using a hybrid LTQ-OrbitrapXL mass spectrometer (LC-MS/MS). Over 800 proteins were identified in the muscle samples, among which 141 demonstrated differential (P < 0.05) expression between NORM and SEV. The set of differentially (P < 0.05) expressed proteins was uploaded to Ingenuity Pathway Analysis® (IPA) software to determine the associated biological networks and pathways. The IPA analysis showed that eukaryotic initiation factor-2 (eIF-2) signaling, mechanistic target of rapamycin (mTOR) signaling, as well as regulation of eIF4 and p70S6K signaling were the major canonical pathways up-regulated (P < 0.05) in SEV muscle compared to NORM. The up-regulation of these pathways indicate an increase in protein synthesis which could be part of the rapid growth as well as cellular stress associated with ongoing muscle degeneration and the attempt to repair tissue damage in SEV birds. Furthermore, IPA analysis revealed that glycolysis and gluconeogenesis were the major down-regulated (P < 0.05) canonical pathways in SEV with respect to NORM muscle. Down-regulation of these pathways could be the reason for higher ultimate pH seen in SEV muscle samples indicating reduced glycolytic potential. In conclusion, comparison of proteomic profiles of NORM and SEV muscle samples showed differences in protein profile which explains some of the observed differences in meat quality parameters. Future studies based on these differences could provide valuable insights into various cellular changes and identification of biomarkers related to WS and WB.

Effect of methionine supplementation in chicken feed on the quality and shelf life of fresh poultry meat

The aim of this study was to investigate the influence of different methionine sources and concentrations on the quality and spoilage process of broiler meat. The trial was comprised of 7 treatment groups: one basal group (suboptimal in Methionine+Cysteine; i.e., 0.89, 0.74, 0.69% in DM SID Met+Cys in starter, grower, and finisher diets, respectively) and 3 doses (0.10, 0.25, and 0.40%) of either DL-Methionine (DLM) or DL-2-hydroxy-4-methylthio butanoic acid (DL-HMTBA) on an equimolar basis of the DLM-supplemented groups. The broilers were fed the diets for 35 d, then slaughtered and processed. The filets were aerobically packed and stored under temperature controlled conditions at 4°C. Meat quality investigations were comprised of microbial investigations (total viable count and Pseudomonas spp.), pH and drip loss measurements of the filets. The shelf life of the meat samples was determined based on sensory parameters. After slaughtering, all supplemented meat samples showed a high quality, whereby no differences between the 2 methionine sources could be detected for the microbial load, pH, and drip loss. In comparison to the control group, the supplemented samples showed a higher sensory quality, characterized by a fresh smell and fresh red color. Methionine supplementation had a significant influence on meat quality parameters during storage. The microbial load, pH and drip loss of the chicken filets were positively correlated to the methionine concentration. Additionally, the microbial load at the end of storage was positively correlated to pH and drip loss values. Nevertheless, the microbial parameters were in a normal range and the positive correlation to methionine concentration did not affect the sensory shelf life. The mean sensory shelf life of the broiler filets varied between 7 to 9 d. During storage, no difference in the development of sensory parameters was observed between the supplemented groups, while the spoilage process of the basal group occurred slightly faster. In conclusion, methionine concentration, but not methionine source, effected meat quality parameters in breast muscles of broilers.

Effect of electrical stunning frequency and current waveform in poultry welfare and meat quality

This study aimed to evaluate the effects of different stunning frequencies and electrical current waveforms on chicken welfare and meat quality. Two-hundred-thirty-two Cobb broilers, 48 d of age and 2.76±0.47 live-weight, were randomly assigned into 4 stunning treatments - 2 frequencies (300Hz and 650Hz) and 2 current waveforms (direct current [DC] and alternating current [AC]). Broilers were electrically stunned in a water bath in a commercial slaughterhouse (70V, 100mA). The electronarcosis and stunning efficiency were confirmed by assessment of visual parameters (absence of rhythmic breathing, ocular reflex, and coordinated wing flapping) and blood parameters (lactate, glucose, creatine kinase, sodium, and potassium), which were measured after bleeding. The incidence of traumas and injuries was assessed after plucking. Meat quality analysis was performed in Pectoralis major (PM), with determinations of pH, breast yield (PMY), water holding capacity (WHC), water absorption capacity (WAC), thawing loss (DL), cooking loss (CL), shear force (SF), and instrumental color (a*, b*, L*, C*, and h). The interaction between waveform and frequency was significant (P <0.05) only for lactate, sodium, and lightness (L*). Lactate and sodium levels decreased at 300 Hz-DC. Meat lightness increased at 300 Hz-DC. The individual effect of frequency was significant for glucose, creatine kinase, potassium, WHC, PMY, b*, C*, and h. Regarding waveform, AC decreased plasma glucose and DC decreased creatine kinase and WAC. In general, stunning frequency exerts greater influence than waveform on the welfare and meat quality parameters of broilers. The use of frequency at 650Hz proved to render animals efficiently unconscious and to promote greater meat quality.

Incidence of broiler breast myopathies at 2 different ages and its impact on selected raw meat quality parameters

White striping (WS) and woody breast (WB) are 2 poultry meat quality defects that affect the acceptance of raw breast fillets as well as properties of cooked and further processed products. The present study was intended to evaluate the incidence of these conditions in broilers at different ages and to compare the properties of fillets with different degrees of WS and WB. For this study, 1,920 birds were processed, at 6 and 9 wk of age, in a standard commercial inline processing system. After chilling, carcasses were deboned and butterfly fillets were collected and weighed. Individual fillets were scored for normal, moderate, severe, and very severe degrees of WS and WB, and for petechial hemorrhagic lesions (PHEM, 0 - no lesion to 2 - severe lesion). Representative fillets with NORM-WS/WB, SEV-WS, SEV-WB, and SEV-WS/WB were selected and stored at 4°C. After 24h, fillet length, width, cranial height, and caudal height, as well as pH, color, and drip loss were recorded. There was an increase in incidence of severe and very severe WS and WB conditions at 9 wk compared to 6 wk of age. The relationship between fillet weight and the myopathies plateaued at 9 wk of age with more fillets showing a higher score. Mean PHEM scores were higher (P <0.05) in SEV-WS, SEV-WB, and SEV-WS/WB compared to NORM-WS/WB birds, both at 6 and 9 weeks. NORM-WS/WB birds had lower (P <0.05) live and breast weight, breast yield, and cranial and caudal heights, as well as b* value (yellowness) compared to SEV-WS/WB. NORM-WS/WB had lower (P <0.05) pH while NORM-WS/WB and SEV-WS samples showed lower (P <0.05) drip loss when compared to SEV-WB and SEV-WS/WB. The results from this study showed that the severe degrees of WS and WB are associated with heavier and older birds, and thicker breast fillets. Occurrence of severe degrees of WS and/or WB can affect various raw meat quality factors, mainly color and water holding capacity.

Influence of the addition of post-extraction rapeseed meal on the sensoric quality of poultry meat

Complete feed mixtures, very often enriched by the addition of various probiotic preparations, oils, extract, essential oils, mouldings, pollards etc., that are often added as a replacement for animal meals, antibiotic preparations, coccidiostats respectively, are used for feeding of chickens. In addition to the positive effects of these supplements, the final quality of meat may be adversely affected by the accumulation of certain components. The aim of the work was to monitor the influence of adding post -extraction rapeseed meal (PRM) to a broiler feed mixture on the sensory quality of breast and thigh muscle. The experience includes two hybrid combinations of broilers, ROSS 308 and COBB 500. Samples of breast and thigh muscle of broilers fed by a feed mixture with the addition of 10% post -extraction rapeseed meal were compared, using sensory analysis, with a control sample where the broilers were fed by a standard feed mixture without the addition of PRM. It has been found that the addition of post -extraction rapeseed meal to the broilers' feed mixture had a positive effect (p &lt;0.05) on the sensory quality of hybrid ROSS 308, both on the breast and thigh muscle. For COBB 500 hybrid, the quality of both breath and thigh muscle has not been shown to be significantly affected. The addition of 10% PRM affected positively especially the texture properties of ROSS 308, hybrid breast muscle, whereas they were deteriorated in COBB 500. In sensory evaluation, by adding 10% of PRM to the feed mixture, thigh muscle was affected less than breath muscle. Adding 10% PRM to the feed has almost no effect on descriptors of the intensity and pleasantness of smell and the intensity and pleasantness of taste, both in the negative and positive sense, both in breath and thigh muscle. The evaluation of the overall quality of both breath and thigh muscle has turned out more positive for ROSS 308 hybrid, although only slightly. The addition of rapeseed extracted meal to feed hybrids ROSS COBB 308 and 500 had no significant effect on the sensory quality of breast and thigh muscle.

Genome-wide DNA methylation profiles reveal novel candidate genes associated with meat quality at different age stages in hens

Poultry meat quality is associated with breed, age, tissue and other factors. Many previous studies have focused on distinct breeds; however, little is known regarding the epigenetic regulatory mechanisms in different age stages, such as DNA methylation. Here, we compared the global DNA methylation profiles between juvenile (20 weeks old) and later laying-period (55 weeks old) hens and identified candidate genes related to the development and meat quality of breast muscle using whole-genome bisulfite sequencing. The results showed that the later laying-period hens, which had a higher intramuscular fat (IMF) deposition capacity and water holding capacity (WHC) and less tenderness, exhibited higher global DNA methylation levels than the juvenile hens. A total of 2,714 differentially methylated regions were identified in the present study, which corresponded to 378 differentially methylated genes, mainly affecting muscle development, lipid metabolism, and the ageing process. Hypermethylation of the promoters of the genes ABCA1, COL6A1 and GSTT1L and the resulting transcriptional down-regulation in the later laying-period hens may be the reason for the significant difference in the meat quality between the juvenile and later laying-period hens. These findings contribute to a better understanding of epigenetic regulation in the skeletal muscle development and meat quality of chicken.

Effect of acute heat stress and slaughter processing on poultry meat quality and postmortem carbohydrate metabolism

This study investigated the effects of acute heat stress and slaughter processing on poultry meat quality and carbohydrate metabolism. Broilers (200) were randomly divided into 2 groups receiving heat stress (HS; 36°C for one h), compared to a non-stressed control (C). At slaughter, each group was further divided into 2 groups for slaughter processing (L = laboratory; F = commercial factory). L group breasts were removed immediately after bleeding without carcass scalding or defeathering, and stored at 4°C. F group broilers were scalded (60°C, 45 s) after bleeding and defeathering. Then the breasts were removed and cooled in ice water until the core temperature was ≤4°C. Rates of Pectoralis core temperature and pH decline were changed by slaughter processing, but only HS affected ultimate pH in group L. HS muscles had higher L* values (P < 0.05) than controls at 24 h postmortem. Laboratory processing “hot-deboning” increased drip loss, which resulted in a lower cooked loss (P < 0.05). Postmortem glycolysis was affected only by HS. The speed of lactic acid accumulation and glycogen degradation was faster in the HS group than controls at 5 min postmortem. During storage the glycolysis rates were not different (P > 0.05). Sarcoplasmic protein solubility was higher in F processed birds (P < 0.05). HS decreased the solubility of myofibrillar and total protein in the L-slaughtered birds. Thus, HS caused a higher frequency of accelerated muscle glycolysis than controls. Factory processing (chilling) could not completely eliminate the effects of accelerated glycolysis caused by pre-slaughter HS.

Effect of "Wooden Breast" appearance on poultry meat quality, histological traits, and lesions characterization

The purposes of the study were to investigate the effects of Wooden Breast (WB) myodegeneration on poultry meat quality and to give a contribution in typing lesions morphology. At a poultry meat cutting facility, 474 carcasses of a high-breast-yield hybrid chickens were inspected for WB condition, and 30 normal (N) and 30 affected (WB) breast fillets (Pectoralis major) were randomly selected. The WB condition represented 53.2% of the examined carcasses. Weight, cross sectional area (CSA), pH, L*, a*, b* colour values, water-holding capacity, and Warner-Bratzler shear force were determined. Samples were also visually and histologically evaluated. Affected samples were heavier, thicker, paler (P &amp;lt; 0.001), and characterized by palpatory hardness and lower water holding capacity (P &amp;lt; 0.05). Macroscopically, abnormalities were primarily localized in the cranial portion of the fillet and defined by the presence of bulges, petechiae, fluid and clear exudate, and higher pH. Microscopically, the WB condition was characterized by muscle fibres with greater CSA (P &amp;lt; 0.001) and higher giant fibres prevalence (P &amp;lt; 0.01). Data suggest a relationship between breast weight and WB condition.

Effect of probiotics in poultry for improving meat quality

The ban on the use of antibiotic growth promotors in many countries in order to satisfy the consumers’ demands for healthy and safe meat leads to increasing researchers’ interest in finding strategies to maintain chicken health and production. Probiotics which are live microbial compounds are considered a good alternative to antibiotics, as their use in poultry diets has been associated with positive effects on health and growth in birds. Changes in growth performance often affect various meat quality traits and in this context, more and more recent research show that using probiotics as dietary supplements exhibit potential as a natural way to improve poultry meat quality. The review discusses the changes in the physicochemical characteristics as well as fatty acids profile and oxidative stability in poultry meat as affected by various probiotics added to the diet of the birds.

Poultry Meat Quality in Relation to Muscle Growth and Muscle Fiber Characteristics.

Variations in the definition of poultry meat quality exist because the quality traits are not solely based on intrinsic and extrinsic factors but also consumers’ preference. Appearance quality traits (AQT), eating quality traits (EQT), and reliance quality traits (RQT) are the major factors focused by the consumer before buying good quality of poultry meat. AQT and EQT of poultry meat are controlled by physical and biochemical characteristics of muscle fibers which can be categorized into a total number of fibers (TNF), cross-sectional area of fibers (CSAF), and fiber type composition (FTC). In poultry meat, it has been shown that muscle fiber properties play a key role in meat quality because numerous studies have reported the relationships between quality traits and fiber characteristics. Despite intensive research has been carried out to manipulate the muscle fiber to improve poultry meat quality, demand in a rapid growth of poultry muscle has correlated to the deterioration in the meat quality. The present paper reviews the definition of poultry meat quality, meat quality traits, and variations of meat quality. Also, this review presents recent knowledge underlying the relationship between poultry meat quality traits and muscle fiber characteristics.

Proteome Basis of Pale, Soft, and Exudative Broiler Breast (Pectoralis Major) Meat

ObjectivesPale, Soft, and Exudative (PSE) broiler breast meat has poor protein functionality, which leads to quality problems and economic loss in the poultry industry. Proteomics has been applied to characterize the biochemical mechanisms governing tenderness, color, and water holding capacity in meat. However, the proteome basis of PSE has not yet been characterized for broiler breast meat. Therefore, this study was conducted to determine the differences in meat quality (cooking loss and shear force), descriptive sensory characteristics, consumer acceptance, and whole muscle proteome between normal and PSE broiler breast meat. Materials and MethodsMale Hubbard × Cobb 500 birds (n = 1050) were raised in commercial houses. Short-term stressed broilers (n = 900) were hand caught, released to a lighted poultry house at 38°C for 2 h whereas control broilers (n = 150) were hand caught, placed in live haul crates at 21°C for 2 h, and then slaughtered. Broilers were electrically stunned by placing their heads in a saturated saline batch, similar to industry standards. Whole carcasses were stored in metal containers in ice water for 4 h postmortem to mimic the commercial chilling process, and then hand deboned. Broiler breast (Pectoralis major) meat was collected and characterized by pH₂₄ and L*₂₄ as normal (pH₂₄ 5.8 to 6.2, L*₂₄ 45 to 55) or PSE (pH₂₄ 5.4 to 5.7, L*₂₄ 55 to 65) samples. For proteomic analysis, the whole muscle proteome with separated using 2 dimensional electrophoresis and proteins were identified using an LTQ-Orbitrap mass spectrometer. Trained panelists with more than 100 h experience in muscle food sensory evaluation were trained for 20 h for descriptive analysis of broiler breast samples. In addition, consumer acceptability testing of normal and PSE broiler breast samples was conducted (panelists = 55 to 60 per replication; replications = 2) using a 9 point hedonic scale. ResultsNormal broiler breast meat had lower shear force values than PSE meat (P < 0.05). Based on sensory descriptive analysis, normal cooked chicken breast meat was more tender and juicier than PSE breast meat (P < 0.05). Consumer sensory analysis results indicated that 81% of consumer panelists liked normal breast meat whereas 62% of the panelists liked PSE breast meat. Whole muscle proteome profiling identified fifteen differentially abundant proteins in normal and PSE broiler breast samples. Actin α, myosin heavy chain, phosphoglycerate kinase, creatine kinase M type, β-enolase, carbonic anhydrase 2, proteasome subunit α, pyruvate kinase, and malate dehydrogenase were over-abundant (P < 0.05) in PSE broiler breast whereas phosphoglycerate mutase-1, α-enolase, ATP-dependent 6-phosphofructokinase, and fructose 1, 6-bisphosphatase were over-abundant (P < 0.05) in normal meat. ConclusionResults indicate that the over-abundance of proteins involved in glycolytic, muscle contraction, proteolytic, ATP regeneration, energy metabolism and CO₂ hydration in PSE-like breast meat may be related to the meat quality differences between normal and PSE-like breast meat. Based on the protein markers identified in the present study, future studies should focus on identifying the genes responsible for differences in protein abundance and their relationship to poultry meat quality.

Evaluating the Efficacy of Some Antibiotics and Medicinal Plant Extracts Against the Infection of Escherichia Coli and Salmonella Enteritidis and Their Effect on Poultry Meat Quality

Evaluating the Efficacy of Some Antibiotics and Medicinal Plant Extracts Against the Infection of Escherichia Coli and Salmonella Enteritidis and Their Effect on Poultry Meat Quality