1,721,009 research outputs found
Spaghetti Meat Abnormality in Broilers: Current Understanding and Future Research Directions
Full text linkSpaghetti 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
A comparison of water distribution and protein oxidation between poultry and rabbit meat
Full text linkIn the last years, proton Nuclear Magnetic Resonance (NMR) relaxometry has been successfully applied to study water mobility and distribution in porcine meat. In addition, although neglected for decades, the impact of protein oxidation on meat quality traits has been recently reviewed. Within this context, considering the incomplete knowledge on water distribution and mobility in white meats and the lack of information concerning protein oxidation, this study aimed at provide reference values on poultry (chicken and turkey) and rabbit meat. For this purpose, rabbit (L. lumborum muscles from 11 weeks-old males slaughtered at 2.7 kg), chicken (P. major muscles from medium-size 44 days-old male broiler slaughtered at 3.0 kg) and turkey (P. major muscles from 20 weeks-old male birds slaughtered at 21 kg) meat samples (n=8/specie) were selected 24 h post-mortem and used to assess ultimate pH, colour (L*a*b*), NMR relaxation properties and protein oxidation. In detail, proton transverse relaxation (T2) decay curves were recorded, at the operating frequency of 20 MHz, with a Bruker (Milan, Italy) Minispec PC/20 spectrometer, while protein carbonylation was assessed following a novel 2,4-dinitrophenylhydrazine (DNPH)-based method. Overall, ultimate pH values and colour were consistent with previous studies. If compared to both chicken and turkey, rabbit meat exhibited a remarkably higher proportion of the extra-myofibrillar water fraction (2.4 and 2.8 vs. 8.4%; P<0.001) and a consequent decrease in the intra-myofibrillar one (93.7 and 93.3 vs. 88.5%; P<0.001). However, although increased, the extra-myofibrillar water in rabbits appeared to be more tightly bound (lower T2) in comparison to both chicken and turkey meat (130.3 vs. 286.3 and 210.6 ms; P<0.001). These dissimilarities might be related to the different muscle fibre characteristics (e.g. type, size, post-mortem acidification behaviour, etc.). As for protein oxidation, significantly higher carbonyls content were found in turkey and rabbit in comparison with chicken meat (3.10 and 3.60 vs. 1.11 nmol/mg of protein; P<0.001). The lower protein oxidation level observed in chicken meat might be likely related to its lower iron content if compared to both turkey and rabbit meats. In conclusion, providing reference values, this study improved the current knowledge concerning poultry, turkey and rabbit meat quality characteristics
Current Status of Poultry Meat Abnormalities
Full text linkOver 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
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Diet of loggerhead turtles in the Gulf of Manfredonia, South Adriatic Sea: evidence of winter feeding and anthropogenic impacts
No full textInvestigating biological aspects of migratory marine animals like sea turtles is challenging. The Adriatic Sea is a key Mediterranean foraging ground for loggerhead turtles, yet certain feeding behaviors remain poorly known, including winter feeding and foraging within the neritic area of the Gulf of Manfredonia. With high fishing effort, this area experiences considerable turtle bycatch from trawlers during winter, representing an important conservation issue. Insights on how and to what extent the species interacts with anthropogenic threats such as trawlers and debris can be obtained from diet analysis. We examined feces and gut contents from 57 bycaught or stranded turtles to assess active feeding and digestion time during winter, identify and quantify prey items, evaluate feeding patterns among size classes, and ascertain the anthropogenic impact via debris and fishing discard ingestion. Our findings show that turtles feed actively during winter, primarily on benthic items, starting from a small size (32 cm Curved Carapace Length). No size effect was observed on dietary diversity or biomass percentage. We identified 37 Operational Taxonomic Units (OTUs) across 10 dietary groups, with crustaceans and mollusks being most prevalent. Osteichthyes and cephalopods, likely scavenged from trawl discard, were also common, implying intensive local trawling may attract turtles, increasing bycatch and mortality rates. The frequency of anthropogenic material ingestion was comparable to other Mediterranean regions and its presence in feces suggests non-lethal effects, if any. This study shows how information on seasonal feeding behavior can provide insights into how the relationship of the species with the environment and threats changes over time, ultimately steering conservation efforts
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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