• Journal of Animal Science and Technology
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• v.64 no.1
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• pp.155-165
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• 2022

As pork consumption increases, rapid and accurate determination of porcine carcass grades at abattoirs has become important. Non-destructive, automated inspection methods have improved slaughter efficiency in abattoirs. Furthermore, the development of a calibration equation suitable for non-destructive inspection of domestic pig breeds may lead to rapid determination of pig carcass and more objective pork grading judgement. In order to increase the efficiency of pig slaughter, the correct estimation of the automated-method that can accommodate the existing pig carcass judgement should be made. In this study, the previously developed calibration equation was verified to confirm whether the estimated traits accord with the actual measured traits of pig carcass. A total of 1,069,019 pigs, to which the developed calibration equation, was applied were used in the study and the optimal estimated regression equation for actual measured two traits (backfat thickness and hot carcass weight) was proposed using the estimated traits. The accuracy of backfat thickness and hot carcass weight traits in the estimated regression models through stepwise regression analysis was 0.840 (R²) and 0.980 (R²), respectively. By comparing the actually measured traits with the estimated traits, we proposed optimal estimated regression equation for the two measured traits, which we expect will be a cornerstone for the Korean porcine carcass grading system.

• Korean Journal of Poultry Science
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• v.36 no.3
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• pp.223-229
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• 2009

The objective of this study was to investigate the effect of the supplementation of antibiotics on meat quality grade of broiler carcasses under the Korean meat grading system. A total of 34,000 broiler carcasses, which were randomly selected 100 broilers from each farm in 340 broiler farms (305 farms with antibiotics; 35 farms without antibiotics), were used in this study. Average daily weight gain of broilers was not significantly affected by the use of antibiotics. The ratio of quality grade A was higher in the broiler carcasses from the farms with antibiotics supplementation (78.87%) than those without antibiotics (73.46%, P<0.05). The numbers of carcass defects, which are down-grade factors of meat grading system, were much higher in the broiler carcasses produced from the farms without antibiotics supplementation when compared with those with antibiotics. In particular, the incidence of the carcass defect on conformation was approximately 1.8 times higher in the carcasses from the farms without antibiotics supplementation than those with antibiotics, which showed the highest negative correlation with quality grade A. Therefore, the improvement of farm management system, the use of antibiotics alternatives from natural products, and a proper incentive should be considered in various ways to encourage farmers to reduce antibiotics usage in their farm and earn consumers' trust for antibiotics-free products.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.7
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• pp.951-960
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• 2018

Hanwoo cattle are an important food source in Korea and their supply can have a major impact on meat availability for Korean consumers. The Hanwoo population was 1.8 million head in 2005 and gradually increased to 2.6 million in 2015. Per capita beef consumption has also increased, to 11.6 kg per year in 2015, and is expected to continue to increase. Because intramuscular fat percentage is a critical contributor to meat quality, Hanwoo cattle are fed a high-energy corn-based diet for long fattening periods. Long fed diet causes significant alterations in fat percentage in the loin muscle and other areas of the carcass. However, these long feeding periods increase feeding costs and beef prices. Recently, there has been increased Korean consumer demand for lean beef which has less fat, but is tender and priced more reasonably. These consumer demands on the Korean beef industry are driving differing beef production systems and also changes to the beef grading methodology. Korean government has made a significant investment to select bulls with favorable production traits using progeny testing. Progeny tested bull semen has been disseminated to all Hanwoo farmers. A beef traceability system has been employed for all cattle breeds in Korea since 2009. Hanwoo cattle are ear-marked with a 12-digit identification number from birth to slaughter. This number allows traceability of the management history of individual cattle, and also provides information to consumers. Traceability including management information such as herd, farm, year of birth, and carcass data can determine estimated breeding values of Hanwoo. For a sustainable Hanwoo industry, research scientists in Korea have attempted to develop feeds for efficient fattening periods and precision feeding systems based on genetic information for Hanwoo cattle. These initiatives aim to Korean consumer demands for beef and provide more precision management in beef production in Korea.

• Korean Journal of Poultry Science
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• v.32 no.3
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• pp.179-186
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• 2005

This study was conducted to establish a comprehensive guideline for grading system of poultry meat cuts. Slaughter and further processed houses were divided into large(>70,000 heads/day), middle($50,000\~25,000$ heads/day), and small scale(<25,000 heads/day), and the production managers were asked by the Questionnaire. Most poultry meat cuts produced by larger- and middle-slaughter house were consumed by dealers, franchisee and department store in increasing order, whereas further processed poultry meat cuts(small scale) provided meals for the students in the high amount. The packaging step was best f3r the determination of grading in the large slaughter house. This survey indicated that two or more grades were proper to determine the grading in the middle slaughter house, however only two grades were proper for the others. Freshness, bruise, wound, trimming and the inclusion of foreign materials affected to the grading. Poultry meat cuts were accepted for the grading in large-slaughter house, but whole poultry carcass was accepted for the grading in the others. Most managers agreed with that the grading system was only applied for the amounts requested. They also suggested that the grading system of poultry meat cuts were necessary in near future, even though it was not urgent to apply.

• Food Science of Animal Resources
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• v.41 no.2
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• pp.224-236
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• 2021

The objective of this study was to investigate the effects of quality grade (QG) on the physicochemical composition and eating quality attributes of pork belly and shoulder butt. Seventy-two growing-finishing crossbred pigs were slaughtered and their carcasses were graded according to the Korean pork carcass grading system. Based on the grading criteria, the carcasses were classified into: QG 1+ (n=23), QG 1 (n=23) and QG 2 (n=26) groups. At 24 h postmortem, belly and shoulder butt cuts were collected from the QG groups and used for analysis of meat quality, flavor compounds and eating quality attributes. Results showed that the variation in fat content among QG was approximately 2% in the both cut types. The QG showed no effects on all the quality traits: cooking loss, pH and color of the belly or shoulder butt (p>0.05). Thirty-five flavor compounds comprising mainly fatty acids oxidation/degradation-derived products (e.g., aldehydes) and only few Maillard reaction-derived products (e.g., sulfur-and nitrogen-containing compounds) were identified. However, the QG showed a minor effect on the flavor profiles in both the belly and shoulder butt. Regarding the sensory quality, no effects of the QG were found on all the eating quality attributes (color, flavor, juiciness, tenderness and acceptability) for both the belly and shoulder butt cuts (p>0.05). Thus, it may be concluded that the current pork carcass grading standards do not reflect the real quality and value of the belly and shoulder butt cuts.

• Food Science of Animal Resources
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• v.29 no.4
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• pp.494-499
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• 2009

To investigate the relationship between the carcass defects considered by a meat grader and quality grade A, a total of 59,700 broiler carcasses, which were reared from September 1, 2007 to August 31, 2008 and randomly selected from 597 broiler farms with 100 broilers in each farm, were graded by a meat grader using the Korean meat grading system. The average slaughter weight of the broilers increased at the 31- to 33-d age but decreased after the 37-d age. The average daily gain to grade A ratio of the broilers was highest in autumn, and the bruises, flesh blemishes, and abnormalities of the carcasses were found to have been most frequent in winter (p<0.05). The number of economical defects (EDs) increased with the increase in the slaughter age, and the correlation coefficients of the EDs and grade A were -0.88, -0.48, and -0.12 in terms of the conformation, exposed flesh/cuts/tears, and skin discolorations of the carcasses, respectively. The correlation coefficients of the non-economical defects (NEDs) and the grade A of the broiler carcasses were -0.16, -0.22, and -0.32 in terms of the feathers, alien substances, and carcass treatment, respectively. The total number of defects (EDs + NEDs) and the grade A were highly correlated (-0.93), and in particular, the correlation between the grade A and the EDs was -0.91. It can be deemed that the grade A from a meat grader is highly correlated with the EDs. Therefore, the results suggest that broiler carcass grade evaluation using a meat grading system can provide direct information on profits in the market. The resulting carcass grade of broilers can also provide the information needed to decide on a proper incentive for a farm that has attained a good quality grade.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• v.11 no.2
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• pp.440-446
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• 2006

• Korean Journal of Veterinary Service
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• v.43 no.2
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• pp.45-52
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• 2020

A grading system is implemented to evaluate the meat quality of Hanwoo. In the grading system, grade 1++A is the highest grade. Livestock farms breed Hanwoo with good quality feed in order to obtain the highest grade. In this process, the content ratios of muscles in individual regions can be changed. To find out the muscle distribution ratios of Hanwoo steers, grade 1A, 1+A, and 1++A Hanwoo steers were compared with grade 1+A Hanwoo female. Grade 1A Hanwoo steers had higher ratios of shank (SK), brisket and flank (BF), neck chain (NC), and inside skirt (IS) meats and a lower ratio of striploin (SL) meat compared to grade 1+A Hanwoo feamle. Grade 1++A Hanwoo steers had higher ratios of neck (NK) and loin (LN) meats and lower ratios of inside skirt (IS), tenderloin (TL), top round (TR), eye round (ER), bottom round (BR), bottom sirloin triangle (BST), and knuckle (K) meats compared to grade 1+A Hanwoo steers. In comparison between grade 1A and 1++A Hanwoo steers, the ratio of shank (SK) was significantly lower in higher quality meats. If the changes are continuously studied to improve the process so that the ratios of partial meats of the regions highly preferred by consumers can increase, it will contribute to increases in the incomes of livestock farms and enable Hanwoo to grow into a global brand.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.12
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• pp.1807-1814
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• 2008

This study was carried out to investigate the effects of housing system on the carcass and meat qualities of Hanwoo (Korean cattle) bulls. Fourteen 6 months-old male calves were randomly divided into two groups. The first group was individually tethered using double neck-bar tethers. The second group was collectively loose-housed in the pen. They were raised for 15 months prior to slaughter. At 24 h post-slaughter chilling, the carcasses were weighed and evaluated by official grader for carcass traits. At 48 h post-slaughter chilling, the M. longissimus at the $12-13^{th}$ thoracic vertebra from each carcass was collected and stored at $4{\pm}0.2^{\circ}C$ for 7 days for meat quality analysis. There were no significant differences in dressing percentage and carcass yield index between groups. Meat from loose bulls had lower marbling score (p<0.05) and fat content (p<0.01) but higher PUFA concentration (p<0.001) than that from tethered bulls. There were no significant differences physical and sensory properties, aroma pattern, TBARS value, metmyoglobin concentration and CIE color values during refrigerated storage between groups. Compared to tethering, loose-housing bulls produced lower fat content and healthier meat without different physical properties, acceptability, and lipid and color stabilities.

• Korean Journal of Veterinary Service
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• v.36 no.2
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• pp.121-125
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• 2013

The survey was conducted to investigate the relation between slaughter inspection results and the quality of cattle carcasses by inquiring animal products grading service results of Korea Institute for Animal Products Quality Evaluation (KAPE) about partial-disposed cattle carcasses after dismantling inspection. Of the 13,586 slaughtered cattle, 1,343 (9.9%) cattle heads were partially disposed from January to August, 2012 at slaughterhouses in Gwangju area, Korea. Of the 1,343 partial disposed cattle, 613 (45.6%) cattle carcasses were graded into above "Grade 1". Among partially disposed 1,171 Hanwoo heads, 613 (52.3%) cattle carcasses were graded into above "Grade 1". However, none of dairy and beef cattle carcasses were graded into above "Grade 1" out of 163 and 9 partial disposals, respectively. Of the 221 partial disposals by enteric fat necrosis, 139 carcasses were graded into above "Grade 1", and the ratio; 62.9% (P=0.001), was higher than that (50.3%) of total cattle carcass grade which is above "Grade 1". From these results, it is suggested that quality of cattle carcasses which is mainly determined by marbling might be related to the fatty lesions such as fatty liver and enteric fat necrosis.