Current Status of Poultry Meat Abnormalities

Over the past decade, the poultry industry has faced an increasing occurrence of growth-related muscular abnormalities that mainly affect fast-growing genotypes selected for their production performances (high growth rate and breast yield). These abnormalities, termed white striping (WS), wooden breast (WB) and spaghetti meat (SM), primarily affect the superficial portion of pectoralis major muscles. Despite their distinctive phenotypes, WS, WB, and SM conditions entail common histological features, i.e., they might share common causative mechanisms underpinning their occurrence. Meat affected by growth-related abnormalities is harmless for human nutrition since no specific biological or chemical hazards have been found to be related to its consumption. However, WS, WB, and SM abnormalities negatively affect both quality traits and technological properties of raw and processed meat, causing relevant economic damages in the poultry industry. This paper aims to provide an update about the current status of poultry meat abnormalities, giving useful insights about their impact on meat quality, the possible causative mechanisms, methods for mitigation, and future perspectives

Sarcomere lengths in wooden breast broiler chickens

The present study aims to measure the sarcomere lengths in normal broiler muscles and in non-lesion sites of breast muscles focally affected by Wooden Breast (WB). For this purpose, twenty Pectoralis major muscles (10 unaffected and 10 WB-focally affected cases) were sampled and used to measure sarcomere length by laser diffraction method. When compared with their unaffected counterpart, WB cases exhibited 13% longer sarcomeres (1.91 vs. 1.69 mu m; p <.001) measured within the non-lesioned site of the muscle. Although it is not simple to draw conclusions about the lesion properties based on the non-lesion area, but as the fibres are bound to each other, it may be reasonable to anticipate that the hardened consistency observed in WB is not ascribable to a more intense contraction of the sarcomeres. In addition, considering the current knowledge concerning this condition, it might be assumed that the longer sarcomeres observed in WB are not triggering the development of this condition but are rather a consequence of the profound alteration in the muscular structure resulting from it. Indeed, despite the outstanding improvements in the live and slaughtering traits, the selection programmes carried out in the past years have resulted in a reduced capillarization and impaired oxygen supply to the Pectoralis major of fast-growing hybrids thus affecting the physiology of its constituting fibres as well as maybe impairing their ability to synthetise new sarcomeres. This may result in a skeletal muscle injury, which would ultimately lead to necrosis and fibrosis.Peer reviewe

Spaghetti Meat Abnormality in Broilers: Current Understanding and Future Research Directions

open3noSpaghetti meat (SM) is a recent muscular abnormality that affects the Pectoralis major muscle of fast-growing broilers. As the appellative suggests, this condition phenotypically manifests as a loss of integrity of the breast muscle, which appears soft, mushy, and sparsely tight, resembling spaghetti pasta. The incidence of SM can reach up to 20% and its occurrence exerts detrimental effects on meat composition, nutritional value, and technological properties, accounting for an overall decreased meat value and important economic losses related to the necessity to downgrade affected meats. However, due to its recentness, the causative mechanisms are still partially unknown and less investigated compared to other muscular abnormalities (i.e., White Striping and Wooden Breast), for which cellular stress and hypoxia caused by muscle hypertrophy are believed to be the main triggering factors. Within this scenario, the present review aims at providing a clear and concise summary of the available knowledge concerning SM abnormality and concurrently presenting the existing research gaps, as well as the potential future developments in the field.openBaldi, Giulia; Soglia, Francesca; Petracci, MassimilianoBaldi, Giulia; Soglia, Francesca; Petracci, Massimilian

Effect of the exposure to oxidation and malondialdehyde on turkey and rabbit meat protein oxidative stability

The present study aimed at evaluating the effect of the exposure to a strong oxidative environment (100&nbsp;mM NaClO) and the concurrent incubation with different malondialdehyde (MDA) concentrations (0 to 5&nbsp;mM) on protein carbonylation, free thiol groups, total heme pigments, and on the relative concentration of the different myoglobin (Mb) derivatives in turkey thigh and rabbit hind leg meat to elucidate their eventual role in inducing oxidative modifications on the protein fraction. With regard to turkey meat, the addition of a strong oxidant resulted in remarkably higher (P &lt; 0.001) carbonyls along with a reduction in free thiol groups (which become undetectable). The relative concentration of MbO2 and MetMb was significantly affected (P &lt; 0.001) and total heme pigment was reduced by 62% when fresh meat is compared to its oxidized counterpart. The addition of MDA 2.5&nbsp;mM (or greater) resulted in a 1.4-fold increase in carbonyls and a tendency (P = 0.07) has been observed for free thiol groups whose content decreased as the MDA level increased. Overall, the aforementioned results are in agreement with those obtained on rabbit hind leg meat in which a three-fold increase (P &lt; 0.001) in carbonyls and a remarkably higher (P &lt; 0.001) MetMb content coupled with a 53% reduction in free thiol groups were found. No significant differences ascribable to MDA addition were found. In conclusion, exposing turkey and rabbit meat to the same environment resulted in distinctive oxidative changes that might be related to the compositional traits and a species-specific susceptibility of the meat toward oxidation. Practical Application: Protein and lipid oxidation have been investigated in different meat types; nevertheless, the knowledge concerning the interaction between these two phenomena is limited. According to their compositional traits (high Polyunsaturated fatty acids (PUFA) and heme pigment content), turkey and rabbit leg meats are particularly susceptible to oxidation. Providing information concerning the oxidative stability of turkey thigh and rabbit hind leg meat exposed to strong oxidative conditions and to a concurrent increasing content of a secondary product of lipid oxidation, the findings of the present study can be useful when proper processing strategies and storage conditions have to be implemented for manufacturing processed products

Meat Quality for Further Processing

In the past few decades, the genetic selection programs carried out to increase the production traits of broilers and obtain high-growth rate and breast yield hybrids led to profound changes in muscle structure and metabolism resulting in an increased incidence of abnormalities mainly affecting the Pectoralis major muscle. White-striping (WS), wooden breast (WB) and poor cohesion (PC) defects are of relevant importance. Within this scenario, this PhD thesis aimed at deepening the current knowledge concerning histological features, quality traits and technological properties of broiler pectoral muscles affected by abnormalities, clarifying their peculiarities and similarities as well as investigating the underlying mechanisms involved in their occurrence. Irrespective of the type of abnormality, similar histological alterations including profound degenerative myopathic changes, variable fibers cross-sectional area as well as proliferation of loose connective tissue and fat deposition were observed within the endomysial and perimysial spaces of the Pectoralis major muscles affected by abnormalities. As for quality traits, the abnormal muscles exhibited severely impaired technological properties (reduced water-holding/-binding capacity and altered texture) with the alterations being more pronounced within the superficial layer of the cranial portion of the muscle when more than one abnormality coexist. With regard to chemical composition, an overall higher moisture, fat and collagen content to the detriment of protein and total heme pigments levels were found in abnormal muscles which exhibited altered sodium and calcium homeostasis as well as 204 differentially expressed genes related to several functional categories. In addition, the hardened consistency of the WB cases is only partially counteracted by the endogenous proteolytic processes taking place during the post-mortem period. In conclusion, it is reasonable to hypothesise the existence of a complex network of biological changes responsible for the phenotypic features and the consistent impairment of muscular metabolism of the abnormal muscles

A critical review of the mechanisms involved in the occurrence of growth-related abnormalities affecting broiler chicken breast muscles

In the past decade, the poultry industry has faced the occurrence of growth-related muscular abnormalities that mainly affect, with a high incidence rate, the Pectoralis major of the fast-growing genotypes selected for their production performances (high growth rate and breast yield). These myopathies are termed as White Striping, Wooden Breast, and Spaghetti Meat and exhibit distinctive phenotypes. A spatiotemporal distribution has been demonstrated for these disorders as in the early stage they primarily affect the superficial area in the cranial portion of the muscle and, as the birds grow older, involve the entire tissue. Aside from their distinctive phenotypes, these myopathies share common histological features. Thus, it might be speculated that common causative mechanisms might be responsible for the physiological and structural perturbations in the muscle associated with these conditions and might underpin their occurrence. The present review paper aims to represent a critical survey of the outcomes of all the histologic and ultrastructural observations carried out on White Striping, Wooden Breast, and Spaghetti Meat affected muscles. Our analysis has been performed by combining these outcomes with the findings of the genetic studies, trying to identify possible initial causative mechanisms triggering the onset and the time-series of the events ultimately resulting in the development and progression of the growth-related myopathies currently affecting broilers Pectoralis major muscles. Several evidences support the hypothesis that sarcoplasmic reticulum stress, primarily induced an accumulation of misfolded proteins (but also driven by other factors including altered calcium homeostasis and accumulation of fatty acids), may be responsible for the onset of these growth-related myopathies in broilers. At the same time, the development of hypoxic conditions, as a direct consequence of an inadequate vascularization, triggers a time-series sequence of events (i.e., phlebitis, oxidative stress, etc.) resulting in the activation of response mechanisms (i.e., modifications in the energetic metabolism, inflammation, degeneration, and regeneration) which are all strictly related to the progression of these myopathic disorders

Photography and cyberfeminism: mobilization, subjects and bodies

El presente trabajo plantea una aproximación a dos posibles categorías de análisis para el abordaje de fotografías artístico-periodísticas registradas durante movilizaciones feministas argentinas y difundidas a través de Instagram como acción ciberfeminista. Las categorías son sujetos y cuerpos, y la finalidad de este cuestionamiento es la de problematizar las enunciaciones de las fotógrafas y los fotógrafos y las consecuentes representaciones que se fomentan desde estas imágenes, dando cuenta así del potencial que poseen las mismas para desplazar las representaciones más tradicionales y para volverse un producto constitutivo para el debate social. En ese sentido, las categorías de análisis aquí propuestas pretenderán, desde una lectura semiótica, dar parte de las posibles diferencias y similitudes existentes entre dichos discursos visuales y, además, detectar si la perspectiva interseccional o disidente es tomada en cuenta en los encuadres a analizar.The present work proposes an approach to two possible categories of analysis for the approach of artistic-journalistic photographs registered during Argentine feminist mobilizations and disseminated through Instagram as cyberfeminist action. The categories are subjects and bodies, and the purpose of this questioning is to problematize the enunciations of the photographers and the consequent representations that are promoted from these images, thus realizing the potential that they possess to displace the representations more traditional and to become a constitutive product for social debate. In this sense, the categories of analysis proposed here will seek, from a semiotic reading, to give part of the possible differences and similarities between said visual discourses and, in addition, to detect whether the intersectional or dissident perspective is taken into account in the frames to be analyzed.Facultad de Periodismo y Comunicación Socia

<<Il calcio è come la poesia, un gioco che vale la vita>>: i resoconti dagli stadi di Alfonso Gatto

Alfonso Gatto had a strong passion for sport, especially for cycling and football. The Salerno poet followed the sport throughout his life and throughout the entire span of his journalistic activity. From cycling to football to the Olympics, Gatto took a long and long time on behalf of several competitive events. The contribution analyzes the articles taken from the football column La palla al balzo

Effect of different arginine-to-lysine ratios in broiler chicken diets on the occurrence of breast myopathies and meat quality attributes

This study was carried out to evaluate the effect of different digestible arginine-to-lysine (dig Arg:Lys) ratio in broiler diets on the occurrence of breast myopathies, productivity, and meat quality traits. A total of 1,755 1-day-old Ross 308 male chicks was randomly divided in 3 experimental groups (9 replications/group): CON, fed a 4 feeding-phases commercial diet (dig Arg:Lys ratio = 1.05, 1.05, 1.06, 1.07, respectively in starter, grower I, grower II and finisher phase), and ARG2 and ARG3 groups fed CON diet supplemented respectively with 20 and 30% higher levels of crystalline L-arginine (dig Arg:Lys ratio = 1.25, 1.25, 1.26, 1.27 and 1.35, 1.35, 1.36, 1.37, respectively). Productive performance was recorded throughout the rearing cycle. At processing (43 d), breasts (n = 150/group) were randomly collected to evaluate the incidence and severity of white striping (WS), wooden breast (WB), and spaghetti meat (SM) defects (3- points scale).Meat quality traits, such as color, pH, drip and cook losses, marinade performances, and proximate composition were determined on 12 fillets/group. Although productive performance and meat quality traits resulted not significantly affected, the occurrence of some breast myopathies was modified by the dietary treatments. ARG2 and ARG3 exhibited a significantly higher percentage of breast without WS compared to CON (28 and 41 vs. 17%, respectively; P < 0.001). ARG3 reported the lowest percentage of breasts with severe WS (11 vs. 27 and 31%, respectively for ARG3, ARG2, and CON; P < 0.001) and the highest of those showing no SM abnormality (81 vs. 69 and 65%, respectively for ARG3, ARG2, and CON; P < 0.01). Furthermore, a numerical reduction of breasts with severe WB was observed in ARG3 (12 vs. 25 and 19%, respectively for ARG3, ARG2, and CON; P = 0.12). In conclusion, the dietary supplementation of arginine to increase the dig Arg:Lys ratio by about 30% in respect to the current recommendations for broiler chickens has positive implications on the occurrence of some breast meat abnormalities