Wooden breast lesions in broiler chickens in the UK

Relationship among Sex, Skin Color, and Production Parameters of Broiler in Pectoral Myopathies

Breast anomalies in broilers, especially wooden breast (WB) and spaghetti meat (SM), cause high economic losses to the poultry meat sector. In order to identify the parameters that have a causal effect and to reduce the incidence of these myopathies, 141,792 broilers were analyzed in a total of 1477 batches using a visual grading system. The relationship among productive parameters such as the feed conversion ratio, live weight, growth rate, and mortality, was evaluated. Effects due to skin color (white vs. yellow), broiler sex (male, female, and mixed groups), feed presentation (grain vs. mash), and veterinary treatments (treated vs. untreated) were also included in the statistical study. Live weight was observed to have a significant effect (p < 0.001) on WB incidence, which increased by 1.11 for each 100 g of weight. Weight did not significantly affect the incidence of SM. Males had a higher incidence of WB and a lower incidence of SM than females. The incidence of both myopathies varied between samples that turned out to be significantly affected by some of the variables considered in the model, such as grain feeding and the feed conversion ratio. Controlling these factors in the broiler production could help to reduce the incidence of WB and SM.

Development of Imaging System for Online Detection of Chicken Meat with Wooden Breast Condition

In recent years, the wooden breast condition has emerged as a major meat quality defect in the poultry industry worldwide. Broiler pectoralis major muscle with the wooden breast condition is characterized by hardness upon human palpation, which can lead to decrease in meat value or even reduced consumer acceptance. The current method of wooden breast detection involves a visual and/or tactile evaluation. In this paper, we present a sideview imaging system for online detection of chicken breast fillets affected by the wooden breast condition. The system can measure a physical deformation (bending) of an individual chicken-breast fillet through high-speed imaging at about 200 frames per second and custom image processing techniques. The developed image processing algorithm shows the over 95% classification performance in detecting wooden breast fillets.

Techniques for in vivo assessment of myopathies in broiler chicken breasts using a biopsy as a support tool

An experiment was conducted to validate non-invasive evaluation techniques as in vivo evaluation tools for the myopathies wooden breast and white striping that affect broilers, using biopsy as a support tool. It evaluated 30 Cobb 500® broiler chickens in a completely randomized design consisting of two sexes (males and females) and 15 replications per treatment. At 14, 21, 35, 42 and 49 days, the surface temperature of the birds' breasts was recorded using infrared thermography, analysis of fillet depth, and echogenicity by ultrasound imaging. All broiler chickens were sent for biopsy at 21, 35 and 42 days to collect a fragment of the pectoral muscle for descriptive morphological analyses of histological lesions and muscle fibre morphometry. Males had higher echogenicity values at 14, 21 and 42 days. There was no influence of bird sex on the occurrence of the wooden breast and white striping myopathies at 49 days of age in broilers selected and submitted to the biopsy protocol. There was a general trend of decreasing surface temperature for both sexes according to their age. Muscles with less area occupied with fibres had a lower surface temperature. It was concluded that ultrasonography with a 3.5 MHz transducer detects muscle changes after 28 days of age, which is consistent with the myopathic lesions studied. Infrared thermography is a potential method for detecting changes in breast temperature indicating myopathic lesions. A biopsy can be used as an auxiliary tool in the study of myopathies in broiler chicken breasts.RESEARCH HIGHLIGHTS Detection of changes in the breast muscle after 28 days of age with ultrasonography.Changes in the surface temperature range of pectoral muscle with infrared thermography.Use of biopsy as a tool for early diagnostic evaluation in broiler myopathies.

Effect of Aging on the Quality of Breast Meat from Broilers Affected by Wooden Breast Myopathy

This study aimed to evaluate the effects of aging on the quality of breast meat from broilers affected of wooden breast. Samples that were classified as normal (control), moderate (hardness verified only in one region of breast fillet), and severe (hardness verified in all the extension of breast fillet) were evaluated fresh and after three and seven days of aging. Normal samples and samples with a moderate degree of myopathy showed greater water-holding capacity, which may benefit the processing industry of poultry meat. During the aging process, increase was observed in total collagen concentration (from 0.41% in normal samples to 0.56% in samples with severe degree). Samples of chicken breast affected by moderate degree showed higher myofibril fragmentation index (MFI = 115) than normal chicken samples (95.65). Although chicken samples affected with severe degree of wooden breast myopathy are more tender than normal chicken breasts, they produce more exudate, which can be detrimental to the processing of poultry meat. The aging process may improve the reduction of cooking weight loss and protein loss in exudation of broilers' breasts affected by wooden breast myopathy.

Hypoxia further exacerbates woody breast myopathy in broilers via alteration of satellite cell fate

Woody breast (WB) condition has created a variety of challenges for the global poultry industry. To date, there are no effective treatments or preventative measures due to its unknown (undefined) etiology. Several potential mechanisms including oxidative stress, fiber-type switching, cellular damage, and altered intracellular calcium levels have been proposed to play a key role in the progression of the WB myopathy. In a previous study, we have shown that WB is associated with hypoxia-like status and dysregulated oxygen homeostasis. As satellite cells (SC) play a pivotal role in muscle fiber repair and remodeling under stress conditions, we undertook the present study to determine satellite cell fate in WB-affected birds when reared in either normoxic or hypoxic conditions. Modern random bred broilers from 2015 (n = 200) were wing banded and reared under standard brooding practices for the first 2 wk post-hatch. At 15 d, chicks were divided in 2 body weight-matched groups and reared to 6 wk in either control local altitude or hypobaric chambers with simulated altitude of 6,000 ft. Birds were provided ad libitum access to water and feed, according to the Cobb recommendations. At 6 wk of age, birds were processed and scored for WB, and breast samples were collected from WB-affected and unaffected birds for molecular analyses (n = 10/group). SCs were isolated from normal breast muscle, cultured in vitro, and exposed to normoxia or hypoxia for 2 h. The expression of target genes was determined by qPCR using 2^−∆∆Ct method. Protein distribution and expression were determined by immunofluorescence staining and immunoblot, respectively. Data were analyzed by the Student's t test with significance set at P < 0.05. Multiple satellite cell markers, myogenic factor (Myf)-5 and paired box (PAX)-7 were significantly decreased at the mRNA and protein levels in the breast muscle from WB-affected birds compared to their unaffected counterparts. Lipogenic-and adipogenic-associated factors (acetyl-CoA carboxylase, ACCα; fatty acid synthase, FASN, malic enzyme, ME; and ATP citrate lyase, ACLY) were activated in WB-affected birds. These data were supported by an in vitro study where hypoxia decreased the expression of Myf5 and Pax7, and increased that of ACCα, FASN, ME, and ACLY. Together, these data indicate that under hypoxic condition, SC change fate by switching from a myogenic to an adipogenic program, which explains at least partly, the etiology of the WB myopathy.

Effects of Storage on Quality Traits of Sausages Made with Chicken Breast Meat Affected by Wooden Breast

Simple Summary

Studies of the meat quality of modern birds and their respective myopathies are important to clarify the influence of these on the meat quality of the animals. The constant genetic evolution that birds have undergone is the most plausible cause for the onset of Wooden Breast Myopathy. The processing of byproducts, such as sausages, represents an alternative to avoid the losses that this myopathy generates to the poultry industry due to discards of chickens affected by different degrees of wooden breast myopathy.

Abstract

The aim of this study was to examine the effects of storage on the quality of sausages made with breast from chickens affected by wooden breast myopathy (WBM). Breast samples from male broilers slaughtered at 48 days old were used. Normal (absence of myopathy), moderate degree (hardness only in one region of the breast) and severe degree samples (hardness over the entire length of the breast) were processed into sausages and evaluated prior to storage and after being vacuum-packed and stored for 7, 14, 21 and 28 days at 4 °C. There was a decrease (p < 0.001) in pH and an increase (p < 0.001) in cooking weight loss in samples of sausages, regardless of the myopathy, after 28 days of storage. Sausages produced with chicken breast samples affected by wooden breast myopathy presented higher (p < 0.0001) moisture concentration (72% for the severe degree) and higher (p = 0.0224) protein concentration (17.27% and 17.36%, respectively, for the moderate and severe degrees) than sausages made of normal samples (70.72% and 14.32%, respectively). The results indicate that sausages produced with meat from birds moderately and severely affected by the myopathy show higher oxidative stability. Fresh sausages produced with breast meat from birds affected by wooden breast syndrome may be stored (4 °C) for up to 28 days without exhibiting the characteristic rancid taste and smell. In sensory analysis, no differences were observed between the formulations, which suggests that the consumers approved the samples regardless of the disease severity in the meat used for the making of the sausages. The current results show that chicken meat affected by wooden breast myopathy can be used for producing fresh sausages in the industry.

Studying the Effects of Collagenase (Type 1) on the Collagen in Woody Breast Meat

Abnormal collagen infiltration in the Pectoralis major, breast muscle, of fast-growing big broilers has led to woody breast (WB) myopathy resulting in meat quality issues. Mechanisms to degrade the collagen were investigated to potentially improve WB texture. Freshly deboned WB fillets (n = 5 per trial; 3 trials) were ground and divided in to 25 g portions. Aqueous collagenase Type I solution (1 mL) from concentrations of 2.5, 5, and 10 mg/mL were incorporated in ground WB samples (n = 3 samples/treatment × 3 trials). Ground WB with 1 mL water acted as a control. All the samples were placed at 4 °C for 24 h and frozen at -80 °C. Control samples without any treatment or water addition (n = 3/trial) were frozen immediately upon grinding. Data collected on total (TC), soluble (SC), and insoluble collagen (IC) content was analyzed using one-way ANOVA with Tukey's honestly significant difference (HSD) (p ≤ 0.05). Fresh WB fillets had TC, SC, and IC content of 19.5, 4.9, and 14.6 mg/g, respectively. The addition of collagenase decreased (p ≤ 0.05) the IC to 5.8 mg/g in the 10 mg/mL treatment after 24 h. Converting IC to SC using collagenase can potentially help the poultry industry to reduce WB toughness.

Muscle Metabolome Profiles in Woody Breast-(un)Affected Broilers: Effects of Quantum Blue Phytase-Enriched Diet

Woody breast (WB) myopathy is significantly impacting modern broilers and is imposing a huge economic burden on the poultry industry worldwide. Yet, its etiology is not fully defined. In a previous study, we have shown that hypoxia and the activation of its upstream mediators (AKT/PI3K/mTOR) played a key role in WB myopathy, and supplementation of quantum blue (QB) can help to reduce WB severity via modulation of hypoxia-related pathways. To gain further insights, we undertook here a metabolomics approach to identify key metabolite signatures and outline their most enriched biological functions. Ultra performance liquid chromatography coupled with high resolution mass spectrometry (UPLC-HRMS) identified a total of 108 known metabolites. Of these, mean intensity differences at P < 0.05 were found in 60 metabolites with 42 higher and 18 lower in WB-affected compared to unaffected muscles. Multivariate analysis and Partial Least Squares Discriminant analysis (PLS-DA) scores plot displayed different clusters when comparing metabolites profile from affected and unaffected tissues and from moderate (MOD) and severe (SEV) WB muscles indicating that unique metabolite profiles are present for the WB-affected and unaffected muscles. To gain biologically related molecule networks, a stringent pathway analyses was conducted using IPA knowledge-base. The top 10 canonical pathways generated, using a fold-change -1.5 and 1.5 cutoff, with the 50 differentially abundant-metabolites were purine nucleotide degradation and de novo biosynthesis, sirtuin signaling pathway, citrulline-nitric oxide cycle, salvage pathways of pyrimidine DNA, IL-1 signaling, iNOS, Angiogenesis, PI3K/AKT signaling, and oxidative phosphorylation. The top altered bio-functions in term of molecular and cellular functions in WB-affected tissues included cellular development, cellular growth and proliferation, cellular death and survival, small molecular biochemistry, inflammatory response, free radical scavenging, cell signaling and cell-to-cell interaction, cell cycles, and lipid, carbohydrate, amino acid, and nucleic acid metabolisms. The top disorder functions identified were organismal injury and abnormalities, cancer, skeletal and muscular disorders, connective tissue disorders, and inflammatory diseases. Breast tissues from birds fed with high dose (2,000 FTU) of QB phytase exhibited 22 metabolites with significantly different levels compared to the control group with a clear cluster using PLS-DA analysis. Of these 22 metabolites, 9 were differentially abundant between WB-affected and unaffected muscles. Taken together, this study determined many metabolic signatures and disordered pathways, which could be regarded as new routes for discovering potential mechanisms of WB myopathy.

Application of Bioelectrical Impedance Analysis to Detect Broiler Breast Filets Affected With Woody Breast Myopathy

Woody breast (WB) myopathy in modern broilers is causing major meat quality issues and consumer complaints. The poultry industry is sorting out WB filets through the inconsistent manual hand-palpation method. Bioelectrical impedance analysis (BIA) method was evaluated as a rapid and objective WB detection method. Freshly deboned broiler breast filets (15 filets × 2 categories × 3 trials) were sorted (hand-palpation) into severe woody (SW) and normal (N) categories were analyzed for BIA values, cook loss, texture (BMORS) method. SW filets had significantly (P < 0.05) higher resistance and reactance compared to N indicating BIA can be used to detect WB filets. In another experiment, we determined the ability of the BIA to differentiate between four WB severity levels using the whole filet. Significant differences were observed in resistance and reactance of normal and other WB categories, however, there were no significant differences among mild, moderate and severe WB categories. Segmental BIA of those filets indicated that BIA can be used to separate cranial, medial and caudal region of the breast filet based on the presence of WB myopathy. Accidental discovery of spaghetti breast in the samples demonstrated the significance of compounding different factors in analyzing WB meat using BIA.

Molecular Phenotyping of White Striping and Wooden Breast Myopathies in Chicken

The White Striping (WS) and Wooden Breast (WB) defects are two myopathic syndromes whose occurrence has recently increased in modern fast-growing broilers. The impact of these defects on the quality of breast meat is very important, as they greatly affect its visual aspect, nutritional value, and processing yields. The research conducted to date has improved our knowledge of the biological processes involved in their occurrence, but no solution has been identified so far to significantly reduce their incidence without affecting growing performance of broilers. This study aims to follow the evolution of molecular phenotypes in relation to both fast-growing rate and the occurrence of defects in order to identify potential biomarkers for diagnostic purposes, but also to improve our understanding of physiological dysregulation involved in the occurrence of WS and WB. This has been achieved through enzymatic, histological, and transcriptional approaches by considering breast muscles from a slow- and a fast-growing line, affected or not by WS and WB. Fast-growing muscles produced more reactive oxygen species (ROS) than slow-growing ones, independently of WS and WB occurrence. Within fast-growing muscles, despite higher mitochondria density, muscles affected by WS or WB defects did not show higher cytochrome oxidase activity (COX) activity, suggesting altered mitochondrial function. Among the markers related to muscle remodeling and regeneration, immunohistochemical staining of FN1, NCAM, and MYH15 was higher in fast- compared to slow-growing muscles, and their amount also increased linearly with the presence and severity of WS and WB defects, making them potential biomarkers to assess accurately their presence and severity. Thanks to an innovative histological technique based on fluorescence intensity measurement, they can be rapidly quantified to estimate the injuries induced in case of WS and WB. The muscular expression of several other genes correlates also positively to the presence and severity of the defects like TGFB1 and CTGF, both involved in the development of connective tissue, or Twist1, known as an inhibitor of myogenesis. Finally, our results suggested that a balance between TGFB1 and PPARG would be essential for fibrosis or adiposis induction and therefore for determining WS and WB phenotypes.

Research Note: Dietary phytase reduces broiler woody breast severity via potential modulation of breast muscle fatty acid profiles

Woody breast (WB) myopathy is a major concern and economic burden to the poultry industry, and for which, there is no effective solution because of its unknown etiology. In a previous study, we have shown that phytase (Quantum Blue, QB) reduces the WB severity by 5% via modulation of oxygen homeostasis-related pathways. As WB has been suggested to be associated with lipid dysmetabolism, we aimed to determine the effect of QB on WB and breast muscle fatty acid profile. Male broilers were subjected to 6 treatments (96 birds/treatment): a nutrient adequate control group (PC), the PC supplemented with 0.3% myo-inositol (PC + MI), a negative control (NC) deficient in available P and Ca by 0.15 and 0.16%, respectively, the NC fed with QB at 500 (NC+500 FTU), and 1,000 (NC+ 1,000 FTU) or 2,000 FTU/kg of feed (NC+2,000 FTU). Woody breast and white striping scores were recorded, and fatty acid profiles were determined using gas liquid chromatography. Woody breast-affected muscles exhibited a significant higher incidence of white striping as liquid chromatography analysis reveals an imbalance of fatty acid profile in the breast of WB-affected birds with a significant higher percent of saturated fatty acids (SFA, myristic [14:0], pentadecanoic [15:0], and margaric [17:0]) and monounsaturated fatty acids (myristoleic [14:1], palmitoleic [16:1c], 10-trans-heptadecenoic [17:1t], oleic [18:1c9], and vaccenic [18:1c11]), and lower content of polyunsaturated fatty acids (PUFA) and omega-3 (P < 0.05). Quantum Blue at high doses (1,000 and 2,000 FTU) significantly reduces the percent of SFA and increases that of PUFA compared with the control group. In conclusion, WB myopathy seemed to be associated with an imbalance of fatty acid profile, and QB ameliorates the severity of WB potentially via modulation of SFA and PUFA contents.

Effect of spaghetti meat abnormality on broiler chicken breast meat composition and technological quality

The effects of spaghetti meat (SM) myopathy and sampling location on chicken breast meat physical traits, composition, and protein functionality were investigated using 30 normal (N) and 30 SM boneless fillets. Weight, drip loss, pH, and color traits were determined on intact fillets. Proximate composition, water holding capacity, mineral profile, SDS-PAGE, myofibrillar, and sarcoplasmic protein solubility, and emulsifying properties were assessed on both the superficial (S) and deep (D) layers of the breasts. SM fillets were heavier (P < 0.0001) and exhibited greater drip loss (P = 0.0131) and higher b* index on the skin side of the muscle (P < 0.0001). Muscle condition by layer interaction effect revealed that the superficial portion of SM fillets (SM-S) exhibited the highest moisture (P = 0.0003) and fat contents (P = 0.0011) coupled with the lowest protein (P < 0.0001) and ash contents (P = 0.0458). Total and soluble collagen amounts were higher in N-S and SM-S groups compared with N-D and SM-D (P < 0.0001). SM-S group exhibited the highest calcium (P = 0.0035) and sodium (P < 0.0001) levels. Overall, the myopathy had only minor impacts on protein profiles, while the muscle layer exerted a more remarkable effect. SM fillets exhibited higher pH but a lower myofibrillar protein solubility (P < 0.0001). Salt-induced water uptake, cooking loss, and final yield values suggested a potential impairment of water-holding capacity in SM-affected meat. Sarcoplasmic and myofibrillar emulsion activity indexes were similar between the 2 muscle conditions, but the stability of the emulsions was lower in SM meat. Overall, significant layer and muscle condition by layer effects were not observed in the functional properties of the breast meat. SM exerted a profound and negative impact on breast meat composition that led to detrimental consequences on functionality traits. Given the fundamental role of protein quality for meat processing, these data suggest that a further step toward the understanding of this myopathy should be the investigation of intrinsic protein characteristics.

Temporal characterization of wooden breast myopathy ("woody breast") severity and correlation with growth rate and lymphocytic phlebitis in three commercial broiler strains and a random-bred broiler strain

Wooden breast myopathy (WBM), or "woody breast" or "wooden breast" affects modern, rapidly growing, high breast-yield broiler chickens. Decreased meat quality due to undesirable organoleptic properties and condemnation of affected breast meat cause economic losses. The pathogenesis of WBM remains unknown. In this study, WBM lesion development was determined in three modern broiler strains and Athens Canadian Random Bred (ACRB) broilers, a 1950s unselected broiler chicken. Correlations between WBM severity and incubation temperature profile, sex, strain, body weight, and lymphocytic phlebitis were also determined. At 2, 4, 6, and 8 weeks of age, samples of breast muscle from 10 male and 10 female birds from each strain, incubated under optimal or low-early, high-late temperatures, were scored histologically for severity of WBM and lymphocytic phlebitis. WBM lesions, identified as early as 2 weeks, became progressively more severe with age and growth in the three commercial broiler strains. WBM severity was significantly correlated with lymphocytic phlebitis and body weight. Lymphocytic phlebitis and minimal WBM were present in the ACRB broilers at all samplings, but did not progress in severity over time. There were no significant differences in severity of WBM among the commercial broiler strains, between sexes, or between incubation temperature profiles. The positive correlation between WBM severity and lymphocytic phlebitis indicates vascular injury is likely an important factor in the pathogenesis. Mild muscle lesions in ACRB birds without overt clinical signs indicate subclinical muscle disease may have been present in broilers prior to the description of WBM.

Meat quality traits and proteome profile of woody broiler breast (pectoralis major) meat

Woody breast meat has recently become prevalent in the broiler industry in both the United States and European Union. Recent publications have described the meat quality characteristics of woody breast meat as having hardened areas and pale ridge-like bulges at both the caudal and cranial regions of the breast. The present study investigated the meat quality (pH, color, cooking loss, and shear force) and protein quality characteristics (protein and salt-soluble protein content) in woody breast meat as compared to normal breast meat. In addition, the differences in the muscle proteome profiles of woody and normal breast meat were characterized. Results indicated that woody breast meat had a greater average pH (P < 0.0001) and cooking loss (P = 0.001) than normal breast meat, but woody breast meat did not differ in shear force (P > 0.05) in comparison to normal breast meat samples. The L*, a*, and b* values of woody breast fillets were greater than normal breast fillets (P < 0.0001 to L*; P = 0.002 to a*; P = 0.016 to b*). The woody breast meat had more fat (P < 0.0001) and moisture (P < 0.021) and less protein (P < 0.0001) and salt-soluble protein (P < 0.0001) when compared with normal breast fillets. Whole muscle proteome analysis indicated 8 proteins that were differentially expressed (P < 0.05) between normal and woody breast meat samples. The differences in muscle proteome between normal and woody breast meat indicated an increased oxidative stress in woody breast meat when compared to normal meat. In addition, the abundance of some glycolytic enzymes, which are critical to the regeneration of adenosine triphosphate (ATP) in postmortem muscles, was lower in woody breast meat than in normal breast meat. Proteomic differences provide additional information on the biochemical pathways and genetic variations that lead to woody breast meat. Further research should be conducted to elucidate the genetic and nutritional contributions to the proliferation of woody breast meat in the United States.

Proteomic approach to characterize biochemistry of meat quality defects

Proteomics can be used to characterize quality defects including pale, soft, and exudative (PSE) meat (pork and poultry), woody broiler breast meat, reddish catfish fillets, meat toughness, and beef myoglobin oxidation. PSE broiler meat was characterized by 15 proteins that differed in abundance in comparison to normal broiler breast meat, and eight proteins were differentially expressed in woody breast meat in comparison to normal breast meat. Hemoglobin was the only protein that was differentially expressed between red and normal catfish fillets. However, inducing low oxygen and/or heat stress conditions to catfish fillets did not lead to the production of red fillets. Proteomic data provided information pertaining to the protein differences that exist in meat quality defects. However, these data need to be evaluated in conjunction with information pertaining to genetics, nutrition, environment of the live animal, muscle to meat conversion, meat quality analyses and sensory attributes to understand causality, protein biomarkers, and ultimately how to prevent quality defects.