• Journal of Food Hygiene and Safety
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• v.15 no.3
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• pp.204-208
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• 2000

The contamination levels of food poisoning bacteria was investigated from 350 samples of beef, 338 samples of pork, and 360 samples of chicken during the period from March 1996 to October 1998. The contamination levels of pathogenic organisms were higher in refrigerated meat than packed frozen meat and were relatively higher in chicken and packed meat than in beef The highest level detected for each of the various pathogens was . less than 10,000 cfu/g for Staphylococcus aureus : less than 0.9 MPN/g for Salmonella and Literia monocytogenes: 7MPN/g for Campylobacter jejuni /coli. In the comparisions of cross- contamination ratio of tested meat for low species food poisoning bacteria 14.3% of beef, 23.5% of pork and 55.0% of chicken were contained only one species of pathogen, whereas 2.7 of beef, 5.6% of pork and 14.7% of chicken contained two species and 2.3% of pork contained a total of three species. Generally, pathogens was encounted higher isolation freguency in packed frozen chicken meat than in chilled chickens.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.6
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• pp.895-902
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• 2012

The Korean native chickens (Woorimotdak$^{TM}$, KNC) and commercial broilers (Ross, CB) show obvious differences in meat flavor after cooking. To understand the contribution of protein and peptide for meat flavor, 2-dimensional (2-D) gel electrophoresis and matrix-assisted laser desorption-ionization time-of-flight (MALDI-TOF) mass spectrometry was performed. A total of 16 protein spots were differentially expressed in the breast and thigh meat between the two breeds. A total of seven protein spots were represented by different levels between KNC and CB for breast meat. Among them three protein spots (TU39149, TU40162 and TU39598) showed increases in their expressions in KNC while other four protein spots (BU40125, BU40119, BU40029 and BU39904) showed increases in CB. All nine protein spots that were represented by different levels between KNC and CB for thigh meat showed increases in their expression in KNC. Phosphoglucomutase 1 (PGM 1), myosin heavy chain (MyHC), heat shock protein B1 (HSP27), cytochrome c reductase (Enzyme Q), Glyoxylase 1, DNA methyltransferase 3B (DNA MTase 3) were identified as the main protein spots by MALDI-TOF mass spectrometry. These results can provide valuable basic information for understanding the molecular mechanism responsible for breed specific differences in meat quality, especially the meat flavour.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.171-178
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• 2010

The objective of this study was to compare the quality characteristics of chicken breast and thigh meat from North Korean native chickens (NKNC), South Korean native chickens (SKNC, woorimotdak), and commercial broilers (CB). NKNC thigh meat had a higher crude protein content than CB. In addition, the breasts of NKNC and CB had higher pH values than that of SKNC, but the cooking loss was higher in NKNC. The surface color of the breast and thigh meat of NKNC was darker and redder than that of SKNC and CB. The total collagen content of the breast and thigh muscles was the highest in NKNC, followed by SKNC and CB. A similar trend occurred with breast meat hardness. The content of arachidonic and docosahexaenoic acids was higher in both the breast and thigh muscles of NKNC than in those of the other groups, while the concentrations of linoleic and linolenic acids were higher only in thigh meat. Sensory evaluation did not show any differences among the three different strains of chicken except for the meat color. Sensory panelists preferred thigh meat from SKNC and CB to that of NKNC due to the strong dark color of the NKNC. Based on these results, NKNC had harder breasts based on texture, as well as a darker surface color and higher composition of long chain polyunsaturated fatty acids than CB. The quality characteristics of SKNC tested in this study were intermediate between NKNC and CB; however, SKNC may have a better chance of acceptance by Korean consumers due to the undesirable color of NKNC.

• Animal Bioscience
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• v.34 no.11
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• pp.1839-1848
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• 2021

Objective: The objective of the present study was to investigate the comparative effects of dietary functional nutrients including glutamine (Gln), chromium picolinate (Cr picolinate), vitamin C (Vit C), betaine (Bet), and taurine (Tau) on growth performance, meat quality, immune responses, and stress biomarkers in broiler chickens raised under heat stress conditions. Methods: A total of 420 21-d-old Ross 308 male broiler chickens (initial body weight = 866±61.9 g) were randomly allotted to 1 of 7 treatment groups with 6 replicates. One group was kept under thermoneutral conditions and was fed a basal diet (PC, positive control). Other 6 groups were exposed to a cyclic heat stress condition. One of the 6 groups was fed the basal diet (NC, negative control), whereas 5 other groups were fed the basal diet supplemented with 0.5% Gln, 500 ppb Cr picolinate, 250 mg/kg Vit C, 0.2% Bet, or 1.0% Tau. The diets and water were provided ad libitum for 21 d. Results: Broiler chickens in NC group had decreased (p<0.05) growth performance and immune responses measured based on cutaneous basophil hypersensitivity (CBH), but increased (p<0.05) stress responses measured based on feather corticosterone concentrations and blood heterophil:lymphocyte than those in PC group. However, none of dietary functional nutrients had a positive effect on growth performance of broiler chickens. Dietary supplementation of 250 mg/kg Vit C improved (p<0.05) CBH responses of broiler chickens, but other functional nutrients had no such an improvement in CBH responses. All functional nutrients decreased (p<0.05) stress responses of broiler chickens. Conclusion: Functional nutrients including Gln, Cr picolinate, Vit C, Bet, and Tau at the supplemental levels used in this study decrease stress responses of broiler chickens to a relatively similar extent. However, this reduction in stress responses could not fully ameliorate decreased productive performance of broiler chickens raised under the current heat stress conditions.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.1
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• pp.49-55
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• 1999

The effect of fat supplementation of high calcium (Ca) diets on the performance, intestinal pH, body composition and size and weight of organs in growing chickens were investigated in two experiments. Growing chickens tolerated a high dietary level of Ca (22.5 vs 12.1 g/kg) in the presence of 6.3 g/kg of available phosphorus without any significant effect on performance. Intestinal pH was significantly increased by the addition of excess Ca and fat which probably created the right pH for the formation of insoluble Ca soaps. Excess dietary Ca increased carcass linoleic acid concentration at the expense of palmitic and stearic acid contents, whilst the addition of sunflower oil (80 g/kg diet) to the diet increased carcass linoleic acid concentration at the expense of palmitic acid content of the carcass. Intestinal and visceral organ size and weight were not influenced by excess Ca or fat. However, there was a non significant increase in the intestinal dry weight per unit of length caused by excess dietary Ca. It was concluded that excess dietary Ca of 22.5 g/kg did not significantly influence the performance of meat chickens. However, excess Ca increased intestinal pH and altered carcass fatty acid composition. Fat supplementation did not alter intestinal pH with high Ca diets. Excess dietary fat altered carcass fatty acid composition and reduced protein content. Intestinal and visceral organ size and weights were not influenced by excess dietary levels of Ca of fat.

• Animal Bioscience
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• v.36 no.5
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• pp.679-691
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• 2023

The fat deposition is an important factor affecting chicken meat quality, which is closely related to lipid metabolism of chickens. Therefore, it is important to regulate the lipid metabolism of chickens to improve the chicken meat quality. Plant extracts have special regulatory effects on animal's growth and health and have been widely used in chicken breeding. Some plant extracts have been reported to have functions of changing the fatty acid composition, reducing abdominal fat percentage, and enhancing the intramuscular fat content of chickens by improving the antioxidant capacity, regulating the expression of genes, enzymes, and signaling pathways related to lipid metabolism, modulating intestinal microbiota, affecting hormones level, and regulating DNA methylation. This paper reviewed the application and mechanism of plant extracts on regulating lipid metabolism of chickens to provide a reference for the further application of plant extracts in chicken breeding.

• Korean Journal of Poultry Science
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• v.43 no.2
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• pp.119-128
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• 2016

This study was conducted to compare nutritional composition and taste-related compounds of breast and thigh meats from four lines of Korean native chickens (KNC) Yeonsan Ogye, Hyunin Black, Hwangbong, and Hoengseong Yakdak. White Leghorn (WL) was used as a control. Fifteen male chickens (three chickens in each line) were grown under same condition and slaughtered at 53 weeks old. The contents of Fe and K in KNC, especially Hwangbong breast meat and thigh meat of Hyunin Black and Hoengseong Yakdak, were higher than WL. The contents of Na were lower in KNC compared with WL regardless of parts (p<0.05). Vitamin A contents were higher in thigh meat of WL and Hyunin Black, and vitamin $B_1$ contents were lower in Hoengseong Yakdak than other lines. Vitamin $B_3$ were higher in breast meat of four lines of KNC and thigh meat of Hoengseong Yakdak than WL. Total amino acid contents were higher in breast meat of KNC than WL. The level of good-tasting amino acids were significantly higher in breast meat of Hoengseong Yakdak and WL, and thigh meat of Hyunin Black and WL than other lines of chickens (p<0.05). The ratio of good-tasting amino acids to bitter tasting amino acids was higher in breast meat of Hoengseong Yakdak and thigh meat of Hyunin Black than WL. IMP contents were higher in Hyunin Black and WL than other lines of chickens. Based on these results, it can be concluded that four lines of KNC may have superior nutritional quality and taste when compared with WL.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.11
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• pp.1817-1823
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• 2020

Objective: The increasing consumer awareness of food, which can provide health benefits and potentially aid disease prevention, has become the driving force of the functional food market. Accordingly, the aim of this study was to investigate the effects of chicken genotype on the macronutrient content, bioactive peptide content, and antioxidant capacity within different breast meat. Methods: In this experiment, three genotypes of chicken, Thai indigenous, black-boned, and broiler (control), were reared with commercial feed under the same conditions. Thirty chickens were slaughtered at typical market age and the breasts were separated from the carcass to determine macronutrient content using the AOAC method. The antioxidant capacities of the chicken breasts were evaluated by in vitro antioxidant assays and the protein pattern was investigated using gel electrophoresis. Carnosine and anserine, which have antioxidant properties in animal tissue, were determined using high performance liquid chromatography. Results: The results showed that breast meat from Thai indigenous chickens had a greater macronutrient content and higher antioxidant capacity compared with the other genotypes (p<0.05). The protein pattern was similar between genotypes, however Thai indigenous chickens had the greatest myosin and actin content (p<0.05). In addition, carnosine and anserine values were greatest in the black-boned and Thai indigenous chickens compared with the broiler genotype (p<0.05). Conclusion: Thai indigenous chicken breast meat may be classified as a functional food as it has good nutritional value and is rich in antioxidant peptides.

• Food Science of Animal Resources
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• v.38 no.3
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• pp.629-635
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• 2018

The present study investigated the effects of feed form and distiller's dried grain with solubles (DDGS) on meat quality and fatty acids profile of broiler chickens. A total of 720 broilers (Ross 308; average BW [body weight] $541{\pm}5.7g$) were randomly allotted to six treatments. Birds were fed three different feed forms (mash; SP, simple pellet; EP, expanded pellet) and DDGS (0 or $200g\;kg^{-1}$) in a $3{\times}2$ factorial arrangement. The addition of DDGS and EP to the diet resulted in increased shear force of breast meat. Moreover, DDGS inclusion in the diet reduced the concentration of stearic acid and behenic acid in thigh meat. Pelleting (SP and EP) of the diets increased palmitic acid content in the thigh, whereas the linolenic acid content decreased. The breast mass was higher with EP and SP diets than with the mash diet. Feed processing led to increased pectoralis muscle and drum mass compared to mash-fed chickens. In conclusion, our results demonstrated that EP decreased thigh linolenic acid and meat shear force. In addition, DDGS supplementation in broiler hampers meat quality by increasing the shear force.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.11
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• pp.1510-1518
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• 2010

The study was conducted to evaluate the effect of lighting schedule and nutrient density on growth performance, carcass traits and meat quality of broiler chickens. A total of 576 day old Arbor Acre male chickens was used with a $4{\times}2$ factorial arrangement. The four lighting schedules were continuous (23 L:1 D, CL), 20 L:4 D (12 L:2 D:8 L:2 D), 16 L:8 D (12 L:3 D:2 L:3 D: 2 L:2 D) and 12 L:12 D (9 L:3 D:1 L:3 D:1 L:3 D:1 L:3 D) and provided by incandescent bulbs. The two nutrient densities were high (H, starter diet: 13.39 MJ/kg apparent metabolisable energy (AME), 23.00% crude protein (CP); finisher diet: 13.39 MJ AME/kg, 19.70% CP) and low energy and protein level (L, starter diet: 12.03 MJ AME/kg, 20.80% CP; finisher diet: 12.14 MJ AME/kg, 18.30% CP). Houses with dark curtains and solid sidewalls were used. Chickens were randomly allocated to the 8 treatments with each treatment comprising 6 replicates of 12 chickens. Feed and water were available ad libitum. Lighting schedules showed no difference (p>0.05) in growth performance at the end of the experiment. 12 L:12 D significantly reduced (p<0.05) the concentration of malondialdehyde (MDA) compared to 23 L:1 D treatment. Intermittent lighting (IL) schedules produced higher protein content (p<0.001) in breast meat. Birds on high density diets had higher body weight (BW), feed intake (FI) (p<0.001), and feed conversion ratio (FCR) (p<0.001) throughout the experiment with the exception of 36 to 42 d. High nutrient density increased (p<0.05) abdominal fat, decreased (p<0.05) the moisture loss of meat, and reduced percentage of wings and legs. There was a significant lighting schedule${\times}$diet interaction (p<0.001) on FCR for days 8 to 14 and 15 to 21. Results indicated that IL can give similar growth performance in comparison with CL, meanwhile with positive effects on meat quality by increasing protein content and decreasing the concentration of MDA. High nutrient density resulted in greater growth performance.