Effects of ambient temperature on growth performance, slaughter traits, meat quality and serum antioxidant function in Pekin duck

The present study investigated the effects of temperature on growth performance, slaughtering traits, meat quality and antioxidant function of Pekin ducks from 21–42 d of age. Single factor analysis of variance was used in this experiment, 144 21 d-old Pekin ducks were randomly allotted to 4 environmentally controlled chambers: T20 (20°C), T23 (23°C), T26 (26°C) and T29 (29°C), with 3 replicates in each group (12 ducks in each replicate), the relative humidity of all groups is 74%. During the 21-day trial period, feed and water were freely available. At 42 d, the BW (body weight) and ADG (average daily gain) of T26 were significantly lower than T20 (p < 0.05), and the T29 was significantly lower than T20 and T23 (p < 0.05). The ADFI (average daily feed intake) of T26 and T29 were significantly lower than T20 and T23 (p < 0.05). Compared to the T29, the T20 showed a significant increase oblique body length and chest width, and both the keel length and thigh muscle weight significantly increased in both the T20 and T23, while the pectoral muscle weight increased significantly in other groups (p < 0.05). The cooking loss of the T29 was the lowest (p < 0.05). The T-AOC (total antioxidant capacity) of T29 was significantly higher than the other groups (p < 0.05), the SOD (superoxide dismutase) in the T29 was significantly higher than the T23 and T26 (p < 0.05). In conditions of 74% relative humidity, the BW and ADFI of Pekin ducks significantly decrease when the environmental temperature exceeds 26°C, and the development of body size and muscle weight follows this pattern. The growth development and serum redox state of Pekin ducks are more ideal and stable at temperatures of 20°C and 23°C

Carcass and Meat Quality Traits in an Embden×Toulouse Goose Cross Raised in Organic Dehesa

his study assessed the influence of genetic type (Embden-Anser anser, EE; Toulouse-Anser anser, TT and F1 cross, ET) for meat characteristics (carcass, meat quality and fatty acid (FA) profiles), of domestic geese “Anser anser domesticus” raised in dehesa as an alternative, organic feeding system. Carcass and breast muscle weight (p<0.01) were greater for the ET group at the same live weight. None of the groups showed differences in the production of fatty liver with this type of feeding. Higher values were found for maximum Warner–Bratzler shear force (between 7.62 and 8.87 kg/cm2), which implies the improvement of this parameter. High levels of oleic FAs were obtained, especially for the TT group. The polyunsaturated/saturated FA ratio was highest for the ET group (p<0.001), reflecting the optimum nutritional values as a component of a healthy consumer die

Selection-driven chicken phenome and phenomenon of pectoral angle variation across different chicken phenotypes

An appreciation of the synergy between genome and phenome of poultry breed is essential for a complete understanding of their biology. Phenotypic traits are shaped under the influence of artificial, production-oriented, selection that often acts contrary to that which would occur during natural selection. In this comparative study, we analysed the phenotypic diversity of 39 chicken breeds and populations that make up a significant part of the world gene pool. Grouping patterns of breeds found within the traditional, phenotypic models of their classification/clustering required in-depth analysis using sophisticated mathematical approaches. As a result of studying performance and conformation phenotypes, a phenomenon of previously underestimated variability in pectoral angle (PA) was revealed. Moreover, patterns of PA relationship with productive traits were analysed. We propose using PA measurement as a promising new auxiliary index for selecting hens and roosters of breeding flocks in egg production improvement programs

Duck and Goose Meat Product Processing Technology

200 pages, illustrations (some color)

냉장 저장 중 닭과 오리의 골격근에서 단백질 분해로 생성된 펩타이드 및 육질 변

학위논문(석사) -- 서울대학교대학원 : 국제농업기술대학원 국제농업기술학과, 2021.8. Gap-Don Kim.Proteolysis, a phenomenon in which a protein is automatically broken down by the endogenous proteolytic enzymes in meat, and its relationship with meat quality characteristics have been fully studied in beef and pork. However, this topic has not fully dealt with poultry meat, such as chicken and duck. Moreover, previous studies mainly focused on the effect of proteolysis in meat tenderization resulting in degradation of myofibrillar proteins, such as myosin, actin, troponins, desmin, nebulin, etc. Although most meat proteins including sarcoplasmic proteins as well as myofibrillar proteins are affected by the endogenous proteolytic enzymes during meat storage, degradation of whole proteins has not specifically been elucidated on until now. Therefore, this study was conducted to evaluate the degradation of whole proteins in chicken and duck skeletal muscles during cold storage by analyzing proteolysis-induced peptides. In addition, the study evaluated the influence of protein degradation (peptide production) by proteolysis on the change of poultry meat quality. In the first study, the proteolysis trends and meat quality of the chicken pectoralis major (PM) and iliotibialis (IL) muscles stored at 4ºC for seven days were investigated. Chicken PM had a lower moisture and fat content than the IL muscle (P < 0.05). The changes of pH, shear force, lightness, and yellowness of both muscles showed the same tendencies during storage (P < 0.05). After storage, it was found that the purge loss was higher (P < 0.05) in PM than IL muscle, whereas redness was not different between the two muscles (P > 0.05). The different composition of muscle fibers between PM (100% fast type) and IL (88.85% fast and 11.15% slow types) led to differences in proteolysis. A total of 3,468 peptides were detected and derived from 33 proteins of aged chicken PM, and for aged chicken IL muscle, 3,589 peptides were identified from 37 proteins. Quantitative changes in peptides originated from pyruvate kinase, L-lactate dehydrogenase, fructose-bisphosphate aldolase, beta-enolase, creatine kinase M-type, and hemoglobin subunit alpha, and were closely related with changes in meat quality during cold storage. In the second study, proteolysis-induced peptides were quantified from duck PM and IL during 10 days of cold storage. In addition, protease activity (calpains, cathepsins L and B, proteasome 20S, and caspase-3) and meat quality characteristics were evaluated. Duck IL had a higher pH and lightness but lower cooking loss than those of PM (P < 0.05). During the 10-day cold storage, the pH value of PM declined significantly (P < 0.05), while the meat quality traits of IL were not affected by storage (P > 0.05). In PM, the redness increased from day one to day five, while cooking loss showed a lower rate on day 10 compared with that on day five (P < 0.05). For the protease activities, there were no significant differences in the activities of cathepsin B and proteasome 20S during cold storage (P > 0.05). Significantly, the activity of calpains declined gradually after aging (P < 0.05), and that of PM showed a higher activity than that of IL (P < 0.05). The cathepsin L activity of IL and the caspase-3 activity of PM decreased after five days (P < 0.05). A total of 5,155 peptides were detected and derived from 34 proteins of aged duck PM, and 247 peptides were derived from myoglobin. For 32 proteins of IL, there were 4,222 quantitated peptides, most of which were degraded by the actin. Furthermore, the correlation between degraded protein, meat quality characteristics, and proteolytic enzyme activity was determined via principal component analysis. In both PM and IL, the caspase-3 activity was related to the hemoglobin alpha A subunit. In addition, the meat color traits of both muscles were correlated with the glucose-6-phosphate isomerase and glyceraldehyde-3-phosphate dehydrogenase. These findings indicate that there are many proteins affected by proteolysis, and glucose-6-phosphate isomerase and glyceraldehyde-3- phosphate dehydrogenase can be useful markers for predicting or controlling duck meat quality characteristics.식육 내에 존재하는 다양한 종류의 단백질 분해효소의 작용으로 자연적으로 단백질이 분해되는 현상인 단백질 자가분해(proteolysis) 작용과 그로 인한 육질 특성 변화에 대한 연구는 우육 및 돈육에서 많이 수행되어 왔다. 그러나 닭 및 오리와 같은 가금류에서는 이러한 연구가 많이 수행되지 않았고, 더욱이 식육의 연도 향상과 관련이 큰 근원섬유단백질(myosin, actin, troponins, desmin, nebulin 등)의 분해에 국한된 연구가 주를 이루고 있다. 식육 내 단백질 분해효소의 작용은 근원섬유단백질뿐만 아니라 근장단백질을 포함한 대부분의 식육단백질에 영향을 미침에도 불구하고 전체 단백질에 대한 분해작용을 보다 세세하게 규명되지 못했다. 따라서, 본 닭과 오리 골격근에서 단백질 자가분해 작용으로 생성된 펩타이드 분석을 통해 단백질 분해작용을 규명하기 위하여 수행되었다. 또한, 단백질 자가분해(펩타이드 생성) 작용이 가금류 식육의 품질 변화에 미치는 영향도 분석하였다. 첫 번째 연구에서는 닭의 흉근(M. pectoralis major)과 장경근(M. iliotibialis)을 4℃에서 7 일 동안 저장하며 단백질 자가분해 현상과 육질 변화를 분석하였다. 흉근은 장경근보다 낮은 수분과 지방을 함유하고 있었다(P < 0.05). 저장 기간 동안 pH, 전단가, 명도 및 황색도 변화는 두 근육에서 유사한 경향을 나타내었다. 포장감량은 장경근 보다 흉근에서 더 큰 값을 나타냈지만(P < 0.05), 적색도는 두 근육 간 차이를 나타내지 않았다(P > 0.05). 두 근육은 서로 다른 근섬유 조성을 나타내었는데, 흉근은 fast type 의 근섬유로만 이뤄진 반면, 장경근은 88.85%의 fast type 과 11.15%의 slow type 으로 구성되어 있었고, 이러한 근섬유 조성의 차이가 단백질 자가분해 작용에서 서로 다른 경향을 나타내게 하였다. Pyruvate kinase, L-lactate dehydrogenase, fructose-bisphosphate aldolase, beta-enolase, creatine kinase M-type 및 hemoglobin subunit alpha 에서 유래한 펩타이드의 정량적 변화는 냉장 저장 중 계육 품질의 변화와 매우 밀접한 연관성을 나타내었다. 따라서, 육질 변화와 연관성이 높은 단백질 또는 단백질로부터 유래한 펩타이드는 계육 품질 연관 지표로 활용이 가능할 것이다. 두 번째 연구는 오리의 흉근과 장경근을 4℃에서 10 일 동안 저장하면서 펩타이드의 정량적 변화, 육질 특성 변화 및 단백질 분해효소(calpains, cathepsins L and B, proteasome 20S, and caspase-3)의 활성도를 분석하였다. 오리의 장경근은 흉근보다 pH와 명도는 높았으나, 가열감량은 유의적으로 낮았다(P < 0.05). 10 동안 냉장 저장 중 흉근은 pH 가 유의적으로 감소하였으나 적색도는 증가하였다(P < 0.05). 그러나 장경근은 냉장 저장으로 인한 육질 변화를 나타내지 않았다(P > 0.05). 단백질 분해효소 중 cathepsin B 와 proteasome 20S 의 활성도는 냉장 저장 중 변화를 나타내지 않았으나(P > 0.05), calpains 의 활성도는 점차적으로 감소하였다(P < 0.05). 장경근의 cathepsin L 과 흉근의 caspase-3 의 활성도는 저장 5일 후 유의적으로 감소하는 결과를 나타내었다(P < 0.05). 오리의 흉근에서는 총 37 종의 단백질에서 5,155 개의 펩타이드가 확인되었고, 그 중 247 종의 펩타이드가 myoglobin 에서 유래하였다. 장경근에서는 32 개의 단백질에서 4,222 개의 펩타이드가 확인되었고, 다수의 펩타이드가 actin 에서 유래한 것으로 확인되었다. 두 근육 모두 caspase-3 의 활성도와 hemoglobin alpha A subunit 유래 펩타이드의 정량적 변화가 매우 밀접한 연관이 있는 것으로 확인되었고, 육색은 glucosephosphate isomerase 및 glyceraldehyde-3-phosphate dehydrogenase 에서 유래한 펩타이드와 비슷한 변화 경향을 보여주었다. 이상의 결과는 오리 흉근과 장경근의 수많은 단백질이 자가분해작용의 영향을 받으며, 이들 중 몇몇 단백질은 오리육의 품질 특성을 예측하거나 제어하기 위한 지표로 유용하게 활용될 수 있음을 의미한다.Chapter I General Introduction 1 1 Introduction 1 1.1 Research background 1 1.2 Purpose of this study 3 2 Literature Review 5 2.1 Proteolysis in meat 5 2.2 Influence of proteolysis on meat quality 8 2.3 Influence of proteolysis on proteome 9 2.4 Factors affecting proteolysis in meat 13 2.4.1 pH value 13 2.4.2 Ionic strength and concentration 14 2.4.3 Muscle fiber characteristics 14 2.4.4 Proteolytic enzymes 16 Chapter II Quantitative changes of proteolysis-induced peptides in relation to meat quality characteristics of chicken M pectoralis major and M. iliotibialis 20 1 Abstract 20 2 Introduction 22 3 Materials and methods 25 3.1 Sample preparation 25 3.2 Proximate composition 25 3.3 Meat quality characteristics 26 3.3.1 pH 26 3.3.2 Meat color 26 3.3.3 Water-holding capacity 26 3.3.4 Meat tenderness 27 3.4 Immunohistochemistry 27 3.5 Extraction of peptides 28 3.6 LC–MS/MS analysis and label-free quantification 29 3.7 Proteolytic enzymes 30 3.7.1 Activities of cathepsin B & L 30 3.7.2 Activities of calpain and proteasome 20S 31 3.7.3 Activity of caspase-3 32 3.8 Statistical Analysis 32 4 Results 34 4.1 Proximate composition of chicken skeletal muscles 34 4.2 Meat quality characteristics of chicken skeletal muscles 35 4.3 Muscle fiber characteristics (MFC) 37 4.4 Proteolytic enzymes’ activity 39 4.5 Quantitative changes in proteolysis-induced peptides during cold storage 40 4.6 The relationship between proteolysis-induced peptides, meat quality characteristics, and proteolytic enzyme activity 47 5 Discussion 50 6 Conclusion 54 Chapter III Quantitative changes of proteolysis-induced peptides in relation to meat quality characteristics of duck M pectoralis major and M.iliotibialis 55 1 Abstract 55 2 Introduction 57 3 Materials and methods 59 3.1 Sample preparation 59 3.2 Proximate composition 59 3.3 Meat quality charicteristics 60 3.4 Immunohistochemistry 61 3.5 Quantification of peptides 62 3.6 Activity of proteolytic enzymes 63 3 .7 Statistical analysis 64 4 Results 66 4.1 Proximate composition of duck skeletal muscles 66 4.2 Meat quality of duck skeletal muscles 67 4.3 Muscle fiber characteristics (MFC) 69 4.4 Proteolytic enzyme activities 71 4.5 Quantitative changes in peptides during cold storage 72 4.6 The relationship between degraded protein, meat quality characteristics, and proteolytic enzymes’ activity 73 5 Discussion 81 6 Conclusion 84 Overall Conclusion 85 References 87 Abstract in Korean 108석

Rising Stars in Avian Physiology: 2022

We are delighted to present the inaugural Frontiers in Physiology “Rising Stars in Avian Physiology” annual series of article collections. Recognizing the future leaders in avian physiology is fundamental to safeguarding tomorrow's driving force in innovation. This Research Topic will showcase the high-quality work of up-and-coming researchers in the early stages of their careers. These are researchers within 10 years of their PhD or MD completion across the entire breadth of avian physiology, and present advances in theory, experiment and methodology with applications to compelling problems. All Rising Star researchers will be suggested by the editorial office and established Editors within our board in recognition of their influence on the future directions in their respective fields. While future innovations in avian physiology are yet to be discovered, this Research Topic will give the community a hint at whom to follow. This Research Topic is part of the Rising Stars in Physiology Serie

Genetic Diversity and Evolution of Yunnan Chicken Breeds of China

Chickens are the first type of bird that was domesticated and spread widely in the world to cover the growing demand for animal protein from meat and eggs, and it was cultivated from a wild ancestor known Red junglefowl (Gallus gallus). Yunnan Province is considered the most diverse in culture and biology among all the provinces of China. There are a total of more than 24 chicken breeds in Yunnan Province. These chickens are characterized by good quality of their meat and eggs, a good immune system against diseases, and the ability to adapt to various environmental and administrative conditions. Yunnan Province is one of the centers of domestication and evolutionary of chickens in the world. There are many studies that have been conducted to evaluate and study the genetic diversity and evolutionary relationship within and among chicken breeds in Yunnan Province and their relationship with wild chicken species and other chicken breeds using phenotypic markers, protein polymorphisms, SNPs marker, microsatellite marker, and mitochondrial DNA marker. However, there is no review that summarizes these studies, and most of these studies were authored in the Chinese language. Therefore, we have reviewed all studies that have been conducted on Yunnan chicken breeds diversity in Yunnan Province

Recent Advances in OMICs Technologies and Application for Ensuring Meat Quality, Safety and Authenticity

Consumers and stakeholders are increasingly demanding that the meat industry guarantees high-quality meat products with stable and acceptable sensory and safety properties. To do this, it is necessary to understand the mechanisms that underlie the conversion of muscle into meat, as well as the impact of pre- and post-harvest procedures on the final quality and safety of meat products. Over the last two decades, sophisticated OMICs technologies—genomics, transcriptomics, proteomics, peptidomics, metabolomics and lipidomics, also known as foodomics—have been powerful approaches that extended the scope of traditional methods and have established impressive possibilities of addressing meat quality issues. Foodomics were further used to elucidate the biological basis/mechanisms of phenotypic variation in the technological and sensory quality traits of meat from different species. Overall, these techniques aimed to comprehensively study the dynamic link(s) between the genome and the quality traits of the meat that we eat compared to traditional methods, hence improving both the accuracy and sensitivity thanks to the large quantities of data that can be generated. This Special Issue focused on the cutting-edge research applications of OMICs tools to characterize or manage the quality of muscle foods. The research papers applied transcriptomics, targeted and untargeted proteomics, metabolomics, and genomics, among others, to evaluate meat quality, determine the molecular profiles of meat and meat products, discover and/or evaluate biomarkers of meat quality traits, and to characterize the safety, adulteration, and authenticity of meat and meat products

Molecular mechanisms underlying the impact of muscle fiber types on meat quality in livestock and poultry

In the past, the primary emphasis of livestock and poultry breeding was mainly on improving the growth rate, meat production efficiency and disease resistance. However, the improvement of meat quality has become a major industrial focus due to the ongoing advancements in livestock and poultry breeding. Skeletal muscles consist of multinucleated myofibers formed through the processes of myoblast proliferation, differentiation and fusion. Muscle fibers can be broadly classified into two main types: slow-twitch (Type I) and fast-twitch (Type II). Fast-twitch fibers can be further categorized into Type IIa, Type IIx, and Type IIb. The proportion of Type I and Type IIa muscle fibers is positively associated with meat quality, while the presence of Type IIb muscle fibers in skeletal muscle tissue is inversely related to meat quality. Consequently, muscle fiber composition directly influences meat quality. The distribution of these fiber types within skeletal muscle is governed by a complex network, which encompasses numerous pivotal regulators and intricate signaling pathways. This article aims to succinctly outline the parameters utilized for assessing meat quality, elucidate the relationship between muscle fiber composition and meat quality as well as elaborate on the relevant genetic factors and their molecular mechanisms that regulate muscle fiber types in livestock and poultry. This summary will enrich our comprehension of how to improve meat quality in livestock and poultry, providing valuable insights for future improvements