• Journal of Animal Science and Technology
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• 제66권5호
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• pp.1069-1078
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• 2024

Woody breast (WB) is one of muscle myopathy found in chicken breast, characterized with enlarged size and extremely stiff texture. The WB condition is one of the most prevalent quality issues in the modern poultry industry. WB has been shown to be heritable, but no effective detection method of WB severity in live birds exists for the selection purpose. The objective of this study was to determine potential of a non-invasive, portable digital palpation device as WB detection method that can be used for the selection to estimate the heritability of WB. The physical and functional properties of WB was also investigated in comparison with normal breast (NB). Two hundred ten breast muscles were obtained from a local processing plant one day after harvest and sorted based on WB scoring (1 for NB and 2 and 3 for WB). The samples were subjected to physical and physicochemical analyses, determining biomechanical properties (muscle tone, stiffness, elasticity, relaxation, and creep), pH, color, cooking yield, and texture (firmness and compression energy were used for raw meat and shear force and energy for cooked meat). The least squares means of the following variables were significantly different between WB and NB (p < 0.01): stiffness (603.4 vs 565.8; N/m), and elasticity (1.40 vs 1.55). However, relaxation and creep were not significantly different (p > 0.05). These results collectively showed that biomechanical properties of WB differ from NB. The degree of muscle stiffness in WB can be considered as a trait to be selected. The WB score showed strong negative correlations with cooking yield (-0.77) and cooked L^*(-0.74), which means that as the breast becomes harder, the cooking yield decreases, and the color becomes darker after cooking. The WB score showed high correlations with physical and functional characteristics and exhibited strong correlations with the biomechanical properties measured by the device. Therefore, the results indicated that the digital palpation device has potential to detect the WB severity (degree of stiffness) of breast muscle.

• Asian-Australasian Journal of Animal Sciences
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• 제20권12호
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• pp.1865-1873
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• 2007

An experiment was performed to evaluate the effects of dietary metabolizable energy (ME) and lysine on carcass characteristics and meat quality in Arbor Acres (AA) broilers from 1 to 56 days of age. A total of 2,970 1-d-old male broiler chicks were randomly allocated to nine dietary treatments (three ME levels in combination with three lysine levels), and dietary ME and lysine concentrations were formulated by varying corn, soybean meal, tallow, and L-lysine sulfate concentrations. Live body weight (BW), carcass weight (CW), dressing percent, breast muscle weight (BMW), yield of breast muscle, muscle color (CIE L*, a*, and b*), pH values 45 min and 24 h postmortem ($pH_{45}$, and $pH_{24}$), meat shear force value (SFV), and water loss rate (WLR) were evaluated. Results showed that live body weight and dressing percent increased (p<0.05) as dietary energy increased. Higher dietary lysine content improved breast muscle weight. Neither carcass weight nor yield of breast muscle was affected by dietary energy or lysine content. Higher ME increased the b* value (p = 0.067) and $pH_{24}$ value (p<0.05), whereas it decreased SFV (p<0.05) and WLR (p = 0.06). Only water loss rate was influenced (p<0.01) by dietary lysine, which was higher in broilers from the high lysine diet as compared to those from medium or low lysine diets. The $pH_{45}$ value and L* value of breast muscle were not affected by ME or lysine. Significant interaction of dietary ME and lysine was found on a* value of breast muscle. These results indicated that dietary ME and lysine had important effects on breast muscle growth and meat quality, however their effects were different. Different concentrations of dietary ME and lysine might be considered to improve meat quality.

• 한국축산식품학회지
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• 제42권3호
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• pp.455-466
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• 2022

The aim of this study was to assess the occurrence of white striping (WS), wooden breast (WB), and WS combined with WS/WB muscle abnormalities in broilers (Ross 500) at different slaughter ages (34, 41, and 48 d). In addition, the influence of these muscle abnormalities at different slaughter ages on quality characteristics (physical dimensions, pH, color index, and chemical composition) was studied. Overall occurrence of muscle abnormalities was 45%, 92%, and 100% at slaughter ages of 34, 41, and 48 d, respectively. It was found that about 39% from the occurrence of muscle abnormalities was not similar in the same bird (left and right fillets). Breast fillets affected by muscle abnormalities had significantly (p<0.05) higher weight than normal fillets. At slaughter age of 34 d, normal fillets had significantly higher L^* (67.37 vs. 61.73 and 63.05, p<0.05), lower a^* (3.25 vs. 4.87 and 5.18, p<0.05) and b^* (4.02 vs. 5.20 and 5.99, p<0.05) than WS and WS combined with WB fillets; respectively. The changes in chemical composition due to muscle abnormalities were more significant at high slaughter age than at low slaughter age. In conclusion, the occurrence of muscle abnormalities was strongly influenced by slaughter age. Moreover, breast fillets affected by muscle abnormalities had different quality characteristics (proximate composition, color traits, and dimensions) in comparison to normal fillets.

• Asian-Australasian Journal of Animal Sciences
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• 제16권4호
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• pp.575-580
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• 2003

We determined the effect of caponization on the carcass and giblet characteristics, and skin and muscle color in Taiwan country chicken cockerels. Caponized birds were surgically altered at 10 weeks old and were fed growing and finishing diets ad libitum during an eighteen-week experimental period. The results showed that the percentage of dressing, heart, feet, thigh, head and neck were significantly (p<0.05) higher in the intact birds, while the capons had a higher (p<0.05) percentage of abdominal fat, intestine, back, wing and breast. Eviscerated weight, breast width, gizzard, liver and spleen ratios were not affected by the treatments. The breast skin color values for lightness (L*) and yellowness (b*) values in the capons were significantly (p<0.05) higher than in the intact birds, but the thigh and back skin were not significantly（p>0.05）different. Compared with the intact birds, the capons had a significantly (p<0.05) less redness (a*) values in the back skin, but were not significantly (p>0.05) different in the breast and thigh skin. The L* value of the thigh muscle was significantly (p<0.05) greater in the capons than in the intact birds, but were not significantly (p>0.05) different in breast and back muscles. The b* values in the breast, back and thigh muscles of the capons were significantly (p<0.05) greater whereas the intact birds had a higher (p<0.05) a* values in the breast, back, and thigh muscles. Moreover, our findings also indicate that the castration resulted in a significant alteration in dressing percentage, carcass region and organ percentage.

• Asian-Australasian Journal of Animal Sciences
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• 제22권8호
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• pp.1195-1201
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• 2009

An experiment was conducted to evaluate the effects of dietary alpha-lipoic acid (LA) on growth performance, carcass characteristics and meat quality in Arbor Acres broilers. A total of 240 1-d-old male Arbor Acres broilers were randomly allocated to 4 dietary treatments (0, 300 ppm, 600 ppm, and 900 ppm dietary LA supplementation, respectively). Birds were slaughtered at 42 days old. Live body weight (BW), average daily gain (ADG), average feed intake (AFI), feed conversion ratio (FCR), dressing percentage, breast muscle percentage, thigh muscle percentage, abdominal fat percentage, muscle color (L*, a*, b*), pH values at 24 h postmortem, meat shear force value (SFV) and anti-oxidative ability were measured. Results showed that addition of 600 ppm or 900 ppm LA decreased BW (p<0.01), ADG (p<0.01) and AFI (p<0.05) compared with other diets. FCR was not affected by dietary LA content. LA had no marked effect on dressing percentage, breast muscle percentage or thigh muscle percentage. Abdominal fat percentage was lower (p<0.05) in the 900 ppm LA supplementation group than the control group. Dietary 900 ppm LA increased (p<0.05) breast and thigh muscle pH value at 24 h postmortem compared with the control treatment. Dietary LA increased thigh muscle a* value, though no significant difference was found in thigh muscle a* value among the treatments. Dietary LA significantly decreased breast muscle L* value (p<0.05), breast muscle b* value (p<0.01) and thigh muscle b* value (p<0.05). Broilers fed LA had higher breast muscle a* value (p<0.05) and thigh muscle L* value (p<0.05). All test groups had lower (p<0.05) breast muscle SFV than the control group. Dietary 600 ppm or 900 ppm LA both decreased (p<0.01) thigh muscle SFV compared with the control treatment. Dietary 900 ppm LA significantly increased (p<0.05) TAOC, SOD and GSHPx compared with no LA treatment. Broilers fed LA had lower (p<0.01) MDA compared with the control treatment. These results suggested that dietary LA enhanced the anti-oxidative ability and oxidative stability, and contributed to the improvement of meat quality in broilers.

• 한국가금학회:학술대회논문집
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• 한국가금학회 2004년도 제21차 정기총회 및 학술발표회
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• pp.95-96
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• 2004

An experiment was conducted to investigate the effects of dietary supplementation of feather meal (FM its) digests on the performance of broiler chicks and taurine content in broiler meat. A total of 1,000 broiler chickens were assigned to five dietary treatments : Control, FM diet(FM), FM+pyridoxine(FM+Pyridox), H$_2$O$_2$ treated FM diet(H$_2$O$_2$-FM) and enzyme treated FM diet (Enzyme-FM). Treated diets were supplemented with FM or FM digests at the level of 5 % to the control diet. During the stater period, weight gain of chicks fed FM+Pyridox was significantly higher(P<0.05) than those of the other FM or FM digest treatments but was not different from the control. Weight gam of overall period were not significantly different among treatments. Feed intake of the control was greater than that of FM or FM digest treatments. Feed conversion ratio(feed intake/gain) of chicks fed FM and H$_2$O$_2$-FM were significantly higher than those of Enzyme-FM and FM+Pyridox, but were not significantly different from the control. Taurine contents of leg and breast mucle were significantly (P<0.01) different among treatments but those of liver were not significantly different. Taurine content of FM+Pyridox was highest in both leg and breast muscle. It was 85 % higher in leg muscle and 15 % higher in breast muscle than that of the control. Sensory evaluation data showed significant but not consistant responses in various parameters. FM + Pyridox treatment showed highest score in aroma of raw leg muscle of male and in juiciness and tenderness of broiled breast muscle of male chickens. Control group showed highest color score in raw leg muscle of female and lowest overall acceptability score in broiled breast and leg muscle of male chicken. It is concluded that taurine can be enriched especially in broiler leg meat by 5 % FM diet supplemented with pyridoxine.

• Asian-Australasian Journal of Animal Sciences
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• 제24권8호
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• pp.1128-1135
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• 2011

This study was conducted to investigate the effect of dietary green tea extract (GTE) on the performance, carcass and gastrointestinal tract (gut) traits, caecal coliform bacteria count, and pH and color (CIE $L^*$, $a^*$, and $b^*$) values of the breast muscle in broilers. A total number of 600 day-old broilers (Ross 308) was allocated to three treatments with four replicates containing 50 (25 males and 25 females) birds. The dietary treatments consisted of the basal diet as the control (0GTE) and diets with GTE at 0.1 (0.1GTE) or 0.2 (0.2GTE) g/kg. Body weights and the feed intake of broilers were measured at 1, 21 and 42 days, the feed intake was measured for different periods and the feed conversion ratio was calculated accordingly. At 42 day four birds per replicate were slaughtered for the determination of carcass and organ weights, caecal coliform bacteria count, and also quality of the breast muscle. The dietary GTE increased the body weight, feed efficiency, carcass weight and dressing percentage and decreased caecal coliform bacteria count of broilers (p<0.05). The 0GTE broilers consumed (p<0.01) less feed than the 0.1GTE birds in the entire experimental period. The relative abdominal fat weight and gut length of broilers in the 0.2GTE were tended to be lower (p<0.07) than those in the 0GTE group. The breast meat from 0.1GTE birds had a lower pH value when compared to that from 0GTE birds. The 0.1GTE broilers had lighter breast meat than 0GTE and 0.2GTE birds. The dietary GTE increased $a^*$ and $b^*$ values of the breast meat. Thus this product appeared to have a measurable impact on CIE color values of the breast meat in broilers. The results of the present study may indicate that the improved production results in the group with added GTE are directly connected with physiological mechanisms such as the regulation of the caecal micro-flora.

• Asian-Australasian Journal of Animal Sciences
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• 제21권10호
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• pp.1501-1505
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• 2008

A broiler experiment was conducted to compare the effects of duration and level of iron-methionine chelate (Fe-Met) supplementation on the iron, copper (Cu) and zinc (Zn) content of broiler meat. Two hundred and fifty hatched Ross broiler chickens were randomly assigned to 5 dietary treatments. Each treatment had 5 replicates of 10 birds (5 males and 5 females) each. Birds were housed in raised floor batteries and fed traditional broiler diets ad libitum for 5 weeks. Dietary treatments were as follows: Control and two levels of Fe-Met (100 or 200 ppm in Fe) supplemented for either the whole period (0-5 wk) or grower period (4-5 wk). Production performance was not significantly affected by treatments. Iron content in the muscles (breast, leg and wing) and organs (liver and spleen) were significantly (p<0.05) increased as the level and duration of Fe-Met supplementation increased. The highest concentration of iron was shown in Fe-Met 200 fed for the whole period. Liver contained the highest amount of iron followed by spleen, leg muscle, wing muscle and breast muscle. Supplementation of Fe-Met 200 for the grower period resulted in higher iron concentration in liver and spleen than supplementation of Fe-Met 100 for the whole period. However, the same treatment resulted in lower iron concentration in muscles (breast, leg and wing) than the treatment of Fe-Met 100 for the whole period. In order to achieve the highest iron enrichment in the muscles, Fe-Met should be supplemented at 200 ppm in Fe for the whole period (5 wks). Fe-Met supplementation increased copper concentration in all muscles and organs except wing muscle. Zinc concentration decreased in breast and wing muscle but tended to increase in leg muscle, liver and spleen by Fe-Met 200 supplementation. Color of muscle was not significantly affected by Fe-Met treatments. However, redness of leg and breast muscle, and yellowness of leg and breast muscle tended to increase by supplementation of Fe-Met for the whole period. It was concluded that iron content of broiler meat can be effectively enriched by supplementation of 200 ppm of Fe as Fe-Met for 5 wks.

• 한국축산식품학회지
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• 제23권3호
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• pp.221-226
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• 2003

본 연구는 도계과정 중 전압의 차이가 육계의 육색에 미치는 영향을 조사하기 위하여 육계 180수를 50과 65V,그리고 90V, 255 Hz, 5 초 조건으로 각각 60수씩 배치하여 실신시킨 후 pH, 보수력, 가열감량, 육색(껍질, 가슴육, 다리육, 날개육)과 혈반(Blood spot) 출현율을 조사하였다. 전기자극에 의한 기절시 전압의 차이에 의한 pH, 보수력과 가열감량에 대한 영향에서 저전압(50V, 255 Hz, 5 초)에 의한 전기자극은 고전압(90V, 255 Hz, 5 초)에 비하여 높은 pH와 보수력 그리고 낮은 가열감량을 보이는 것으로 나타났으나 유의적 차이는 없었다(p>0.05). 50V, 255 Hz, 5초에서 90V, 255 Hz, 5초 동안의 전압의 변화는 부분육별 육색에 있어서는 닭의 껍질, 가슴육과 날개육에는 큰 영향을 미치지는 않았다. 그러나 다리육에 있어서 전압의 증가는 명도와 황색도를 유의적으로 증가시켜 주는 것으로 나타났다(p<0.05). 혈반의 발생율은 미지선(50.56%)과 날개(54.77%)에서 높은 발생율을 보였으며, 다리(8.89%)와 가슴(4.44%)의 표면에서는 낮은 발생율을 보였지만 전압의 변화에 따른 일정한 경향은 보이지 않았다. 본 실험의 결과 도계시 전압의 변화는 닭고기의 pH, 보수력, 육색과 혈반 발생율에 유의적 차이는 없었지만, 다소간에는 영향이 있는 것으로 나타났다. 따라서 전압의 세기, 자극시간, 전류의 세기 등의 복합적 요인을 고려한 다각적 분석이 필요할 것으로 사료되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제23권7호
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• pp.946-951
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• 2010

The objective of this research was to evaluate the effects of dietary supplementation of blood meal (BM) as a source of histidine, and magnesium oxide (MgO) as a catalyst of carnosine synthetase, on carnosine (L-Car) content in the chicken breast muscle (CBM), laying performance, and egg quality of spent old hens. Four hundred eighty laying hens (Hy-Line$^{(R)}$ Brown), 95wk old, were allotted randomly into five replicates of six dietary treatments: T1; 100% basal diet, T2; 100% basal diet+MgO, T3; 97.5% basal diet+2.5% BM, T4; 97.5% basal diet+2.5% BM+MgO, T5; 95% basal diet+5% BM, T6; 95% basal diet+5% BM+MgO. Magnesium oxide was added at 0.3% of diets. The layers were fed experimental diets for 5wk. There were no significant differences in the weekly L-Car content in CBM among all treatments during the total experimental period, but some of the contrast comparisions showed higher L-Car in CBM of T6. The L-Car contents linearly decreased (p<0.01 or p<0.05) as the layers got older except in T4 (p>0.05). There were significant differences in egg weight (p<0.01) and soft and broken egg ratio (p<0.05). The control (T1) was highest in egg weight and T6 was lowest in soft and broken egg ratio. Among the parameters of egg quality, there were significant differences in eggshell strength (p<0.01) and egg yolk color (p<0.05). Magnesium oxide supplementation increased the eggshell strength and BM tended to decrease egg yolk color. Eggshell color, eggshell thickness, and Haugh unit were not influenced by BM and MgO. In conclusion, BM and MgO did not significantly influence the L-Car in CBM of spent layers. The L-Car content rapidly decreased as the layers became senescent. Eggshell strength was increased by MgO supplementation.