Carcass Grade Research Articles

Preliminary genetic analysis of beef carcass data

Selective breeding of farm livestock is one of the most cost-effective ways of improving the performance and efficiency of livestock enterprises. Genetic improvement of British beef cattle over a ten year period was recently estimated to be worth approximately £23, and the benefits continue to rise (Amer et al., 2007). While these returns are impressive, they could be improved by increasing the rate of improvement in the purebred population, for example by increasing the relevance of estimated breeding values (EBVs) to beef production by using final carcass weight and grading information. This study will examine the feasibility carcass weights and classifications from UK commercial abattoirs for the genetic evaluation of cattle for carcass weight, carcass fatness class, and carcass conformation class.

돼지의 교배조합·도체등급 및 출하일령이 도체특성에 미치는 영향

본 연구는 도체 등급판정을 받은 비육돈 LY 및 LYD 교잡종 중 암퇘지 128두와 거세돈 528두, 총 656 두를 공시돈으로 교배조합, 도체등급 및 출하일령별 도체 및 육질특성을 조사하여 고급돈육생산에 필요한 기초적 자료를 얻고자 실시하였다. 교배조합별 도체특성의 변화에서 근내 지방도와 보수력은 두 교배조합 간에 각각 통계적으로 유의한 차이(p<0.05)를 보였으나, 도체중, 등지방 두께, 육색, 도체등급 및 출하일령은 두 교배조합 간에 유의차가 나타나지 않았다. 도체등급별 도체특성 분석에서 도체중은 도체등급이 떨어질수록 유의하게(p<0.05) 무거웠다. 등지방 두께는 도체등급이 높을수록 유의하게(p<0.05) 얇은 성적을 나타났으나, 육색도에서는 도체등급간에 통계적 유의차는 없었다. 보수력은 도체등급 간에 유의한 차이(p<0.05)를 보인 반면에, 출하일령은 유의성 있는 차이는 나타나지 않았다. 출하일령별 도체특성에서 도체중과 등지방 두께는 출하일령 간에 통계적으로 유의하게(p<0.05) 일령이 많을수록 무겁게 나타났으나, 육색은 일령간에 유의한 차이를 보이지 않았다. 근내 지방도는 출하일령이 많을수록 유의하게(p<0.05) 높았으나, 도체등급과 보수력에서는 출하일령이 적을수록 유의하게(p<0.05) 높게 나타났다. 그리고 A 등급 출현율은 출하일령이 높은 돈군보다 166~170 일령 돈군에서 53.5%로 가장 높게 나타났다. 도체형질 간의 상관계수 추정에서 도체중은 등지방 두께와 정(+)의 중등 상관이었으나, 도체등급과는 부(-)의 상관이 존재하였으며, 등지방 두께와 도체등급 간에는 부(-) 상관, 육색과 보수력 간에는 고도의 부(-)의 상관, 그리고 근내 지방도와 보수력은 정(+)의 중등 상관이 각각 존재하였다. This study was carried out to investigate the carcass characteristics of crossbred pigs according to mating system, carcass grade and age at marketing. A total of 656 pigs of 128 gilts and 528 barrows were collected and analyzed at public slaughter house. Differences between LY and LYD crossbred on marbling score and water holding capacity were significantly (p<0.05) found. The influences of LY and LYD crossbred on carcass weight, backfat thickness, meat colour, carcass grade and age at marketing were not significantly showed. The carcass weight of D carcass grade was significantly (p<0.05) heavier than that of the other grade. The backfat thickness was significantly (p<0.05) appeared gradually in accordance with the increase of carcass grade. There was significantly difference among the carcass grades on water holding capacity (p<0.05). The differences among the carcass grades on the meat colour, marbling score and age at marketing were not found significantly. The carcass weight of high age group at marketing was significantly heavier than that of the low age group (p<0.05). The backfat thickness of the group of high age at marketing was significantly thicker than that of the group of low age (p<0.05). There were significant differences among age group at marketing in marbling score, carcass grade, and water holding capacity, respectively (p<0.05). The carcass weight was positively correlated with the backfat thickness but negatively correlated with the carcass grade. The correlation between the backfat and carcass grade was significantly negative. The meat colour was negatively correlated with water holding capacity.

국내 소비자의 돼지고기 선호도와 소비행태 분석

Gye-Woong Kim and Seok-Eun KimDepartment of Animal Resources Science, Kongju National UniversityABSTRACTThis study was carried out to investigate consumer’s preference and purchase behavior of pork including perception of brand-pork in Korea. A total of 504 respondents were surveyed and collected from December, 2007 to February, 2008. Among total respondents, 62.55%(n=314) responded that they liked the pork and respondents who were higher education level showed higher preference(p<0.05). Majority of consumers(61.16%) did not like imported pork. In addition, one who had lower education level and living in rural area disliked more the imported pork. Most consumers preferred to the belly (58.57%) and results indicated that the people who were higher education level preferred a discount mart but who were living in rural area preferred a butcher's shop. Among the purchasing area, a big discount mart was the most preferred (44.64%) and this was also different among the education level(p<0.001) and living areas(p<0.05). The consumers preferred to purchasing a 600g pack for a single purchase. Among total respondents, 42.71% of consumers responded that their priority was reliability of meat quality on choosing the place for purchasing the pork, and the significant difference was highly found in living area groups(p<0.001). The perception of carcass grading system was common scores with the average of 2.79, and there was highly significant difference among education level groups(p<0.001). The average of 3.50 among 5 points for branded pork were evaluated by a total of consumers but the significant differences were not found in all three groups.(Key words :Consumer’s Preference, Consumption Behaviors, Pork)

Accuracy of real-time ultrasound measurements of total tissue, fat, and muscle depths at different measuring sites in lamb1

Accuracy of live ultrasound measurements to evaluate the total tissue depth (GR), as well as fat and LM depths at different scanning sites, was studied in 96 purebred Suffolk and Dorset lambs of both sexes slaughtered between 36 and 54 kg of BW. Before slaughter, 7 real-time ultrasound measurements were taken on lambs: fat and LM depths between the 12th and 13th ribs (transverse) and between the 3rd and 4th lumbar vertebrae (transverse and longitudinal), and GR. After slaughter, the measurements equivalent to ultrasound measurements were taken on digitized images of the cuts on the left half carcass of each lamb. Ultrasound GR and fat depth measurements were closely correlated with the corresponding carcass measurements (0.76 < or = r < or = 0.81). Ultrasound GR measurement exhibited a large error of central tendency, but the level of error due to the disturbance (ED) was comparable with fat depth measurements (ED = 8.5%; residual SD = 2.24 mm; CV of residuals = 9.5%). Ultrasound fat depth measurements were more accurate between the 12th and 13th ribs (error due to regression = 1.20; ED = 0.82) than between the 3rd and 4th lumbar vertebrae (error due to regression = 5.58 and 5.4; ED = 1.10 and 0.93, transverse and longitudinal, respectively), mainly due to image interpretation errors in the lumbar region. Measurements of LM depth demonstrated low variability in the population under study (SD = 2.6 mm), and these ultrasound measurements showed low correlation with the corresponding carcass measurements (0.34 < or = r < or = 0.43). The results of this study demonstrated that ultrasound measurements were more accurate for evaluating fat depth and the GR measurements than for estimating LM depths. Ultrasound GR measurement is a promising measurement, especially where carcass grading systems are based on this carcass measurement.

Effects of two commercial meat tenderizers on different cuts of goat\'s meat in Namibia

Most meat consumed in Namibia is derived from poultry, cattle, sheep and pigs, despite the fact that majority of commercial and communal farmers in Namibia keep goats. Goat's meat is not available in the formal market or in the supermarkets in Namibia and is rarely used locally for domestic or commercial purposes due to ethical reasons, alleged poor taste, toughness and unpalatability. It is regarded by some to be for the poor sector of the community and for export only. Others consider goats as pets and a few consider goat's meat a delicacy for home use only. Research on meat tenderization has been carried out on beef, mutton and pork worldwide but very little has been done on goat meat. Meat tenderness has influence on softness, taste, palatability as well as preparation methods, carcass grade and meat price. Generally meat tenderness is indicated by age and species of the animal that indicate minimum cross linking of collagen and actomyosin effect in the muscles. In an attempt to increase goat's meat consumption in Namibia, two commercial meat tenderizers (acidic and enzymatic) were used and tested for their ability to tenderize different cuts of goat's meat. Three different cuts of the toughest parts of goat's meat, namely back, hind limbs and ribs were used for tenderization and to determine the effectiveness of the tenderizers. The first sample of three cuts was used for tenderizer one (acidic), the second for tenderizer two (enzymatic) and the third sample was un-tenderized and was used as a control. Trained panelists were asked to chew and evaluate tenderness of the coded braised goat meat samples on a hedonic scale and the mean results were subjected to statistical analysis. The results showed that the un-tenderized meat cuts (control) remained tough and hard compared to the tenderized ones, while there was no significant difference (p Keywords : Acidic, enzymatic, goat's meat, tenderizer. AJFAND Vol. 8 (4) 2008: pp. 418-426

Carcass characteristics of Hanwoo (Korean cattle) from different sex conditions, raising altitudes and slaughter seasons

This study was carried out to investigate the carcass characteristics of Hanwoo (Korean cattle) from different sex conditions, raising altitudes and slaughter seasons. The total number of cattle used in this study was 3608 heads which comprised of 1336 bulls and 1660 steers. The data was analyzed according to sex condition (bull and steer), raising altitude (low: 0–100 m and high: 700–800 m) and slaughter season (spring, summer, autumn and winter). At 24 h post-slaughter, the carcasses were weighed and evaluated for carcass traits according to the Korean carcass grading standard by an official grader. Carcass weight, ribeye area, yield index and grade, and meat color, firmness and maturity scores of carcass from bulls were significantly higher ( P < 0.001) than those from steers. Inversely, the backfat thickness, marbling score and quality grade of carcass from steers were significantly higher ( P < 0.001) than those from bulls. The maturity score of carcass from a high area was significantly higher ( P < 0.01) than that from a low area. The ribeye area of carcass from summer was significantly smaller ( P < 0.05) than that from other seasons. The maturity score of carcass from the summer season was highest among that from other seasons and the lowest was that from the winter season. Marbling score and carcass quality grade from the winter season were highest among those from other seasons and the lowest were those from the autumn season. There were no significant interactions between sex condition and raising altitude on carcass traits except the ribeye area. There were significant interactions between sex condition and slaughter season on marbling score and carcass quality grade. There were no significant interactions between raising altitude and slaughter season on all of the carcass traits. There were significant interactions among sex condition, raising altitude and slaughter season on meat color score. It was concluded that sex condition affected muscle and fat depositions on the carcass, raising altitude affected maturity and slaughter season affected ribeye area, maturity and marbling.

Prediction of lamb carcass composition and meat quality using combinations of post-mortem measurements

Various post-mortem measurements (carcass weights, conformation and fatness classes, external carcass dimensions, eye muscle dimensions, subcutaneous fat depth, pH and temperature) were recorded on 197 Texel (TEX) and 200 Scottish Blackface (SBF) lamb carcasses. The potential use of these measurements to predict carcass composition and key meat quality traits was investigated, to enable categorisation of carcasses in the abattoir and/or for use in genetic improvement programmes. By combining different measurements, accurate predictions of dissected carcass muscle weight (adjusted R 2 0.93 in TEX, 0.88 in SBF) and fat weight (adjusted R 2 0.84 in TEX, 0.87 in SBF) were achieved, and moderate predictions of intra-muscular fat (adjusted R 2 0.56 in TEX, 0.48 in SBF), whilst shear force was predicted with low to moderate accuracy (adjusted R 2 < 0.33 across breeds and cuts). Sex, eye muscle dimensions and subcutaneous fat depth improved predictions of carcass composition and intra-muscular fat, whilst pH or temperature provided little additional benefit for these traits, but increased prediction accuracies for shear force. These results could contribute to the development of automated carcass grading systems or help inform breeding decisions.

Prediction of beef eating qualities from colour, marbling and wavelet surface texture features using homogenous carcass treatment

Colour, marbling and surface texture properties of beef longissimus dorsi muscle are used in some countries to grade carcasses according to their expected eating quality. Handheld VIA systems are being used to augment the grader assessments, however attempts have been made to develop higher resolution image systems to give consistent and objective predictions of quality based on these properties. Previous efforts have been unable to model sufficiently the variation in eating quality. A new approach has been applied whereby beef carcasses were subjected to homogenous post-slaughter treatment to minimize variation in eating quality related to other factors such as chilling temperature and hanging method. Furthermore a wider range of features were used to better characterize colour and marbling and the wavelet transform was used to characterize texture. Objective and sensory panel tests were performed to evaluate the beef eating qualities. Classical statistical methods of multilinear regression (MLR) and partial least squares regression (PLSR) were used to develop predictive models. It was possible to explain a greater portion of variation in eating quality than before (up to r 2=0.83). Carcasses were classified as high or low quality with a high rate of correct classifications (90%). Genetic algorithms were used to select the model subsets.

Phaffia rhodozyma 균주를 포함한 복합생균제(Any-Lac, ®)의 급여가 돼지의 성장과 육질에 미치는 영향

항산화물질인 astaxanthin을 함유한 생균제를 첨가하여 비육돈의 성장 및 육질에 미치는 영향에 대해 알아보았다. 암수동수의 10주령의 돼지를 대조구(200두)와 처리구(200두)로 나누어 총 2400두 90일간 사양시험을 실시하였다. 육성률에 있어서 대조구 98.98%, 생균제 처리구 99.85%로 생균제 처리구가 높은 경향을 보였으며, 처리구에서는 일당증체량이 평균 0.91kg으로 대조구 0.84kg 보다 높게 나타났으며(p<0.05), 사료효율도 처리구 2.72, 그리고 대조구 2.89로서 생균제 처리구가 높게 나타났다(p<0.05). 대조구와 비교하여 생균제 첨가구는 암퇘지와 거세돼지 모두에서 도체중이 다소 무겁고, 등심단면적은 넓은 경향을 나타내었다. 또한 도체장은 다소 길게 나타났으나, 반면에 등지방두께는 얇은 경향이었다. 이러한 도체특성은 생균제 첨가구의 도체등급을 향상시켜 A등급 출현율이 높아져 경제적으로 유리한 것으로 사료되었다. 냉도체 등급판정에서도 생균제 첨가구는 암퇘지와 거세돼지 모두에서 대조구에 비해 1+와 1등급 출현율이 높아져 냉도체 등급판정결과를 개선시켰으며, 물퇘지(PSE육) 판정율도 대조구는 물퇘지 발생율이 20~28%인데 비해 생균제 처리구는 10% 내외로 낮았다. 암퇘지와 거세돼지 모두에서 대조구에 비해 생균제 처리구가 등심육의 수분은 낮고 지방은 다소 높았으며, 높은 보수력으로 인해 육즙손실과 가열감량이 낮았고, 전단력이 낮아 고기의 연도가 개선된 경향을 나타내었다. 육색측정에서도 진한 적색을 나타내어 생균제 처리구가 우수한 외관을 나타냈으며, 등심육의 콜레스테롤 수치가 낮아 바람직한 경향을 나타내었다. 지방산함량에서는 대조구와 비교하여 생균제 첨가구는 암퇘지와 거세돼지 모두에서 포화지방산에서는 C18:0(steric acid)함량이 낮았으며, 반면에 불포화지방산에서는 필수지방산인 C18:1(oleic acid)와 C18:2(linoleic acid)의 함량이 높아 우수한 지방산 조성을 나타냈다. 이상의 결과를 종합해 볼 때 돼지에 대한 Phaffia rhodozyma 균주가 함유된 복합생균제의 처리는 도체 등급의 향상과 육질 특성, 지방산 조성 등에 있어서 효과가 인정되어 양돈 생산성 향상에 기여할 것으로 사료된다. This study investigated the effects of dietary probiotics which contained antioxidant astaxanthin on growth performances and meat quality in two pigs farms. A total of 2,400 pigs were gilt and barrow with same number assigned to one of two treatments. The two treatments were control(commercial feed), treatment(probiotics 0.1% feed). Each treatment had 3 replicates. Weight gain, feed intake and feed efficiency were periodically recorded for 90 days. Survival ratio was shown 99.85% in treatment group. Average daily gain was higher in treatment group(0.91kg) than that of control(0.84kg). Back fat thickness was lower in treatment group than that of control, even though the treatment group tended to be higher carcass weight. The treatment group trended higher carcass weight, back fat thickness was lower in treatment group than control. The ratio of carcass grade A was shown higher in treatment than that of control, respectively. Treatment group showed higher value of fat content and water holding capacity. Treatment showed lower value than control in shear force and cooking loss. Hunter value(a and b) of treatment group in meat color was higher than control. Treatment group was lower cholesterol content than control. Control group was shown higher unsaturated fatty acid(stearic acid(C18:0)) value than treatment. Treatment group was shown lower saturated fatty acid(oleic acid(C18:1)) value than that of control. These results suggested that the supplementation of probiotics contained Phaffia rhodozyma could be used effectively for increase productivity of livestock industry.

한우 거세우의 도체형질에 대한 유전모수 추정

본 연구에서는 국가단위 한우 유전능력평가에 적용하고 있는 유전력이 적절한지를 검토하기 위하여 그간의 검정자료를 활용하여 유전모수를 추정하였으며, 향후 보증씨수소 선발지수의 개선 등을 위하여 다형질 개체모형을 활용하기 위한 기초자료로 다형질 모형을 적용하여 도체형질간 유전상관을 추정하였다. 연구결과 도체형질의 유전모수 추정치는 단형질과 다형질에서 매우 유사한 유전력을 나타냈으며 그간 연구자들이 보고한 유전력 범위 안에 있는 것으로 나타나, 아직까지는 국가단위 한우유전능력평가에 적용하고 있는 유전력을 변경할 필요는 없는 것으로 나타났다. 다만, 본 연구에서 추정한 형질 중 근내지방도 형질의 유전력이 그간 추정한 값보다 낮게 추정된 것은 근내지방도판정기준이 변경되어 기존의 1~7등급이 1~9등급체계로 변경한 문제와 8, 9등급을 7등급으로 조정하여 분석한 것에 의한 것일 수도 있을 것으로 보여 근내지방도를 변경 전과 변경 후를 다른 형질로 보아 다형질 분석을 실시하는 등 추가연구가 필요한 것으로 보인다. 한편, 도체중과 배장근단면적 간의 유전상관이 0.63으로 추정되어 현 보증씨수소 선발지수에 포함된 두 형질 중 어느 한 형질은 제거하여도 될 것으로 나타났으며, 현재와 같이 단형질 모형으로 추정한 육종가를 이용하여 선발지수를 구성할 경우 형질간의 유전상관이 고려되지 못하여 선발이 목표와 다르게 이루어질 수 있으므로 다형질 모형을 적용하여 육종가를 추정하고 이를 선발지수에 적용하는 것이 바람직할 것으로 사료된다. 또한 당대검정에서 1차 선발한 가축의 자손에 대하여 능력검정을 실시하는 체계에서는 선택된 자료만 활용하게 되므로 유전모수 추정에 영향을 미칠 수 있으므로 당대검정과 후대검정자료를 동시에 활용하여 유전모수를 추정하는 등에 대한 추가 연구가 필요한 것으로 사료된다. The genetic parameters used in National Hanwoo Genetic Evaluation(NHGE) were needed to be monitored and updated periodically for accounting any possible changes in population parameters due to selection and environmental changes. Genetic parameters were estimated with single and two-trait models with MTDFREML package using 2,791 carcass records of steers collected from Hanwoo Progeny Test Program(HPTP). Single and two-trait models gave similar parameter estimates for all traits. The heritability estimates from single and two-trait models for carcass weight(CW), dressing percentage(DP), eye muscle area(EMA), back fat thickness(BFT) and marbling score(MS) were 0.30, 0.30, 0.37, 0.44 and 0.44, respectively. The heritability estimates for all the traits except BFT were slightly lower than those used in NHGE but seemed to be within the acceptable ranges. However, further monitoring is needed because the data might not have fully reflected the changes such as carcass grading standards in performance testing program. In order to shift statistical model of NHGE from single trait model to multiple-trait model, the genetic correlations between carcass traits were estimated with pairwise two-trait models. The genetic correlation coefficients between CW and DP, between CW and EMA, between CW and BFT and between CW and MS were 0.44, 0.63, 0.17 and 0.06, respectively. Those between DP and EMA, between DP and BFT and between DP and MS were 0.29, 0.40 and 0.20. Those between EMA and BFT and between EMA and MS were －0.24 and 0.15, respectively. The genetic correlation coefficient between BFT and MS was 0.03.

Predicting Longissimusdorsi myoglobin oxidation in aged beef based on early post-mortem colour measurements on the carcass as a colour stability index

Sixty young bulls of the Pirenaica breed, representative of the beef production and marketing system in northern Spain, were used. The carcass grading and weight, pH at 24 h post-mortem, and objective colour measurements (CIE L ∗ a ∗ b ∗) were recorded on the Latissimus dorsi, Rectus abdominis and Longissimus dorsi in order to find indicators and predictors of beef colour stability ( Longissimus dorsi metmyoglobin percentage on ageing for 3, 7 and 14 days) by means of early post-mortem measurements on the carcass. Neither the conformation nor the degree of fattening, under the current EU beef carcass classification system, displayed any statistically significant relationship with colour stability of beef aged 3, 7 and 14 days. However, there was a relationship between the instrumental colour measured on the carcass and the colour stability of the beef. This relationship allowed prediction of colour stability ( Longissimus dorsi MMb percentage) after 3, 7 and 14 days of ageing and 48 h blooming using colour coordinates measured on the carcass.

보리함유 고단백질 사료의 급여가 비육돈의 생산성 및 도체특성에 미치는 영향

본 연구는 보리함유 고단백질 사료의 급여가 비육돈의 생산성 및 도체특성에 미치는 영향에 대하여 알아보기 위해 시험을 실시하였다. 3원 교잡종[(Landrace<TEX>${\times}$</TEX>Yorkshire)<TEX>${\times}$</TEX>Duroc]의 비육돈 56두를 공시하였으며, 시험 개시 시 체중이 85.08 kg이었고, 6주간 사양시험온 실시하였다. 시험설계는 1) CON(기초사료) 및 2) HB5(5% 보리함유 고단백질 사료)로 2개 처리를 하여 처리 당 7반복, 반복 당 4두씩 완전임의 배치하였다. 전체 사양시험 기간 동안의 체중, 일당증체량, 일당사료섭취량 및 사료효율은 처리구간에 유의적인 차이가 없었으며(p>0.05), 육색에 있어서 황색도를 나타내는 b값은 대조구가 HB5처리구와 비교하여 유의적으로 높았다(p<0.05). 보수력은 HB5처리구가 대조구와 비교하여 유의적으로 높았고(p<0.05), 육즙감량은 3일, 5일 및 7일에서 HB5처리구가 대조구와 비교하여 유의적으로 낮은 감량을 나타내었다(p<0.05). 등지방두께, 생시체중, 도체중, 지육율 및 도체등급은 처리구간에 유의적인 차이가 없었다(p>0.05). 결론적으로, 본 시험의 결과 비육돈에 보리함유 고단백질 사료의 급여는 육색, 보수력 및 육즙감량에 영향을 미치는 것으로 사료된다. This study was conducted to evaluate the effects of a high protein diet containing barley on the growth performance and carcass characteristics of finishing pigs. A total of fifty six [(Landrace<TEX>${\times}$</TEX>Yorkshire<TEX>${\times}$</TEX>Duroc)] pigs (85.08 kg in average initial body weight) were used for a 6-week study. Dietary treatments included 1) Basal diet (CON) and 2) High protein diet with barley 5% (HB5). During the entire test periods, there were no significant differences in Average daily gain (ADG), Average daily feed intake (ADFI) and gain/feed ratio between treatments (p>0.05). The b value of M. logissimus dorsi muscle color was significantly increased in CON fed pigs compared to pigs fed the HB5 diet (p<0.05). The water holding capacity (WHC) was higher in HB5 than CON fed pigs (p<0.05). Also, drip loss was significantly decreased in HB5 compared to CON fed pigs (p<0.05). Backfat thickness, live weight, cold carcass weight, dressing, and carcass grade were not significantly affected by either treatment (p>0.05). In conclusion, the results of this study indicate that a high protein diet with 5% barley affects meat color, WHC and drip loss in finishing pigs.

Dual X-ray absorptiometry accurately predicts carcass composition from live sheep and chemical composition of live and dead sheep

Fifty merino wethers (liveweight range from 44 to 81 kg, average of 58.6 kg) were lot fed for 42 d and scanned through a dual X-ray absorptiometry (DXA) as both a live animal and whole carcass (carcass weight range from 15 to 32 kg, average of 22.9 kg) producing measures of total tissue, lean, fat and bone content. The carcasses were subsequently boned out into saleable cuts and the weights and yield of boned out muscle, fat and bone recorded. The relationship between chemical lean (protein + water) was highly correlated with DXA carcass lean ( r 2 = 0.90, RSD = 0.674 kg) and moderately with DXA live lean ( r 2 = 0.72, RSD = 1.05 kg). The relationship between the chemical fat was moderately correlated with DXA carcass fat ( r 2 = 0.86, RSD = 0.42 kg) and DXA live fat ( r 2 = 0.70, RSD = 0.71 kg). DXA carcass and live animal bone was not well correlated with chemical ash (both r 2 = 0.38, RSD = 0.3). DXA carcass lean was moderately well predicted from DXA live lean with the inclusion of bodyweight in the regression ( r 2 = 0.82, RSD = 0.87 kg). DXA carcass fat was well predicted from DXA live fat ( r 2 = 0.86, RSD = 0.54 kg). DXA carcass lean and DXA carcass fat with the inclusion of carcass weight in the regression significantly predicted boned out muscle ( r 2 = 0.97, RSD = 0.32 kg) and fat weight, respectively ( r 2 = 0.92, RSD = 0.34 kg). The use of DXA live lean and DXA live fat with the inclusion of bodyweight to predict boned out muscle ( r 2 = 0.83, RSD = 0.75 kg) and fat ( r 2 = 0.86, RSD = 0.46 kg) weight, respectively, was moderate. The use of DXA carcass and live lean and fat to predict boned out muscle and fat yield was not correlated as weight. The future for the DXA will exist in the determination of body composition in live animals and carcasses in research experiments but there is potential for the DXA to be used as an online carcass grading system.

절식시간이 닭고기 품질에 미치는 영향

본 연구는 육계농장에서 출하전 절식시간(2시간 이내, 2~4시간, 4~6시간)과 도계전 총 절식시간(8시간 이내, 8~12시간, 12시간 이상)이 통닭의 하자발생, 도계등급과 육질에 미치는 영향을 조사하기 위해 수행하였다. 출하전 농장에서의 절식시간은 2~4시간의 경우 2시간 이내나 4~6시간 절식에 비해 사계(p<0.05)와 멍계의 발생율이 낮았으며, 도계등급결과에서도 1등급과 2등급 판정율이 다소 높았다. 출하전 농장에서의 절식시간이 가슴육의 육질에 미치는 영향에서는 2~4시간 절식의 경우 2시간 이내나 4~6시간 절식에 비해 pH와 보수력이 다소 높았고, 육즙손실, 가열감량과 전단력이 다소 낮았다. 출하전 절식시간이 가슴육의 7일간 냉장저장기간 중에 총미생물수에 미치는 영향에서 냉장 4일에서 2~4시간 절식이 2시간 이내의 절식에 비해 유의적으로 낮은 수치를 나타냈다. 도계전 육계의 총 절식시간에서 8시간 이내의 총 절식시간은 12시간 이상의 총 절식시간에 비해 사계와 멍계의 발생율이 낮았으며(p<0.05), 도계등급 결과에서도 1등급 판정율이 유의적으로 높았다. 도계전 육계의 총 절식시간이 가슴육의 육질에 미치는 영향에서는 12시간 이상의 총 절식시간이 8시간 이내나 8~12시간의 총 절식시간에 비해 pH와 보수력이 낮았고(p<0.05), 육즙손실, 가열감량과 전단력이 다소 높은 경향을 보였다. 도계전 총 절식시간이 가슴육의 7일간 냉장저장중에 총미생물수에 미치는 영향에서 12시간 이상의 총 절식시간이 8시간 이내나 8~12시간의 총 절식시간에 비해 다소 높은 경향을 나타내었다. 이상의 결과에서 출하전 육계 농장에서의 절식시간은 2~4시간이, 도계전 총 절식시간은 8시간 이내 또는 8~12시간의 절식시간이 닭고기 최종 품질에 가장 좋은 영향을 나타내었다. This study was undertaken to investigate the effects of feed withdrawal time(FWT) before transport in farm(<2 hrs, 2~4 hrs, 4~6 hrs) and total feed withdrawal time(TFWT) before slaughter(<8 hrs, 8~12 hrs, >12 hrs) on carcass defects, grades and meat quality of broilers. FWT of 2~4 hrs before transport in the farm showed lower incidences of dead-on-arrival chicks(p<0.05) and bruising chicks, and a little higher incidences of 1st or 2nd carcass grade compared to shorter than 2 hrs or 4~6 hrs of FWT in the farm. In the meat quality of breast meat, FWT of 2~4 hrs in the farm tended to show higher pH and water holding capacity(WHC), and lower drip loss, cooking loss and shear force values compared to shorter than 2 hrs or 4~6 hrs of FWT in the farm. In the total microbial counts of breast meat during 7 days of cooler storage, FWT of 2~4 hrs in the farm showed significantly lower value than shorter than 2 hrs of FWT in the farm. In the carcass defects and grades by TFWT before slaughter, TFWT shorter than 8hrs showed lower(p<0.05) incidences of dead-on-arrival chicks and bruising chicks, and higher(p<0.05) incidences of 1st carcass grade than TFWT longer than 12 hrs before slaughter. In the meat quality of broiler breast meat, TFWT longer than 12hrs before slaughter showed lower(p<0.05) pH and WHC values, and a little higher drip loss, cooking loss and shear force values compared to TFWT shorter than 8 hrs or 8~12 hrs before slaughter. In the total microbial counts of broiler breast meat during 7 days of cooler storage, TFWT longer than 12 hrs before slaughter tended to show higher value than TFWT shorter than 8 hrs or 8~12 hrs before slaughter. As a result, 2~4 hrs of feed withdrawal time before transport in the farm and total feed withdrawal time shorter than 8hrs or 8~12hrs before slaughter could be recommended for the production of high quality broiler meat.

한우 거세우 도체중 및 체형형질의 유전모수 추정에 관한 연구

This study was conducted to estimate heritabilities and genetic correlations among carcass weight and body type measurements (Wither height, Rump height, Body length, Chest depth, Chest width, Rump length, Rump width, Thurl width, Hipbone width, Chest girth) obtained from 1,587 records of Hanwoo steers in National Hanwoo Contest. Based on EM-REML algorithm, this study estimated genetic parameters of the carcass weight and body type measurements that greatly affect Hanwoo's carcass grade and body type. The means and standard deviations of each trait were 377.30±45.59 kg , 136.14±4.51 cm , 137.79±4.62 cm , 157.77±6.97 cm , 77.55±3.62 cm, 51.72±4.30 cm , 55.04±3.19 cm , 50.21±2.96 cm , 48.29±2.94 cm , 29.12±2.04 cm , and 217.31±11.36 cm for Carcass weight, Wither height, Rump height, Body length, Chest depth, Chest width, Rump length, Rump width, Thurl width, Hipbone width and Chest girth, respectively. As a result of analysis on the effects by the birth year, the Carcass weight, Wither height, Rump height, Body length, Chest depth, Chest width, Rump length, Rump width, Thurl width, and Chest girth came out highest as 413.4±37.5 kg , 138.4±4.1 cm , 139.9±4.3 cm , 162.1±5.7 cm , 80.8±2.5 cm , 55.3±3.7 cm , 58.0±3.3 cm , 52.9±2.4 cm , 50.9±2.8 cm and 225.9±8.3 cm , respectively in 2005. As a result of analysis on the effects by the birth season, the carcass weight and body type measurements came out highest, respectively in spring. As a result of the analysis on the effects by the birth location, all of the traits came out highest, respectively in Gangwon. In the majority of carcass weights and body type measurements, statistically significant differences were observed depending on the location of birth. The heritabilities of the carcass weight, chest width and chest girth were estimated as 0.242, 0.221 and 0.264 respectively. These heritabilities of such traits were higher than those of other traits (withers height, rump height, body length etc.). Genetic correlation coefficients were estimated to be 0.944 between wither height and rump height, 0.822 between carcass weight and chest width, 0.769 between carcass weight and chest girth. From the results above, if the carcass weight should be improved by body type measurements of Hanwoo steer, it seemed that such factors as, chest width, chest girth, body length and withers height, which have relatively higher genetic correlations with carcass weight, should be considered.

A Comparison of the Meat Qualities from the Hanwoo (Korean Native Cattle) and Holstein Steer

This study was conducted to compare the meat qualities from the Hanwoo (Korean native cattle) and Holstein steer. A total of 48 Hanwoo (Korean native cattle) and Holstein steers (20 months old and averaging 500 kg in weight) were allotted into one of four groups (T1, B1+ meat grade Hanwoo; T2, B1 meat grade Hanwoo; T3, B1+ meat grade Holstein; T4, B1 meat grade Holstein). Meat grade were estimated by the Korean carcass grading system (National Livestock Cooperatives Federation, NLCF, 1998). Water content was higher in both of B1+-grade Holstein and B1-grade Holstein sample. B1+-grade Holstein sample was also higher in crude protein content, whereas ash content was higher in both B1+- and B1-grade Hanwoo samples. Shear force value was significantly lower in Holstein samples compared with Hanwoo samples. In fatty composition, the ratio of unsaturated fatty acid was higher, and saturated fatty acid was lower in Holstein samples. In sensory evaluation, aroma was higher in B1-grade Hanwoo sample than those of other samples, whereas flavor was highest in B1+-grade Hanwoo sample. Tenderness was significantly higher in Holstein samples compared with Hanwoo samples. In conclusion, Hanwoo beef had higher ash contents, aroma, and flavor, whereas meat tenderness was higher in Holstein samples.

Technical note: The United States Department of Agriculture beef yield grade equation requires modification to reflect the current longissimus muscle area to hot carcass weight relationship

With the adoption of visual instrument grading, the calculated yield grade can be used for payment to cattle producers selling on grid pricing systems. The USDA beef carcass grading standards include a relationship between required LM area (LMA) and HCW that is an important component of the final yield grade. As noted on a USDA yield grade LMA grid, a 272-kg (600-lb) carcass requires a 71-cm(2) (11.0-in.(2)) LMA and a 454-kg (1,000-lb) carcass requires a 102-cm(2) (15.8-in.(2)) LMA. This is a linear relationship, where required LMA = 0.171(HCW) + 24.526. If a beef carcass has a larger LMA than required, the calculated yield grade is lowered, whereas a smaller LMA than required increases the calculated yield grade. The objective of this investigation was to evaluate the LMA to HCW relationship against data on 434,381 beef carcasses in the West Texas A&M University (WTAMU) Beef Carcass Research Center database. In contrast to the USDA relationship, our data indicate a quadratic relationship [WTAMU LMA = 33.585 + 0.17729(HCW) -0.0000863(HCW(2))] between LMA and HCW whereby, on average, a 272-kg carcass has a 75-cm(2) (11.6-in.(2)) LMA and a 454-kg carcass has a 96-cm(2) (14.9-in.(2)) LMA, indicating a different slope and different intercept than those in the USDA grading standards. These data indicate that the USDA calculated yield grade equation favors carcasses lighter than 363 kg (800 lb) for having above average muscling and penalizes carcasses heavier than 363 kg (800 lb) for having below average muscling. If carcass weights continue to increase, we are likely to observe greater proportions of yield grade 4 and 5 carcasses because of the measurement bias that currently exists in the USDA yield grade equation.

탈피대두박 급여가 흑돼지의 생산성, 도체 및 육질 특성에 미치는 영향

A total of 360 Berkshire (hog) weighing 25 kg were fed experimental diets containing either dehulled soybean meal (DSBM) or non-dehulled soybean meal (NDSBM) as a major protein source until they reach 80 kg. The pigs were then fed the finisher diets either high (3,265 kcal/kg) or low (2,940 kcal/kg) in ME to evaluate the effects of dietary energy level for finisher phase on the growth performances, carcass and meat quality parameter. In growth performance, daily weight gain (kg/day) was higher (P<0.05) in T1 than in other groups. Feed conversion (feed/gain) was lower (P<0.05) in other groups. In carcass parameter, carcass percentage was higher (P<0.05) in T2 than in T1 and T4. Backfat thickness was lower (P<0.05) in T2 than in T1 and T3. The ratio of up B grade in carcass grade tender to be higher in T2 than in other groups. In meat quality, chemical composition was similar between groups. WHC was slighter higher in T1 than in other groups. Shear force was tender to be higher in T1 than in other groups. Hunter L and a in meat color were tender to be higher in T2 than in other groups. Hunter L in backfat color was thender to be higher in T1 than in other groups. The results indicate that growth performance and carcass parameter of Berkshire were improved by the dehulled soybean meal as comparison with non-dehulled soybean meal during growing and finishing periods.

Factores asociados con la calidad de la carne. I parte: la terneza de la carne bovina en 40 empresas ganaderas de la región Caribe y el Magdalena Medio

La metodología desarrollada para evaluar la calidad organoléptica de la carne bovina inició con la clasificación de 46.155 canales bovinas que abastecían cinco frigoríficos ubicados en La Dorada, Montería, Sincelejo, Valledupar y Barranquilla, usando el Sistema Nacional de Clasificación de Canales y Cortes de Carne Bovina desarrollado por el Instituto Colombiano de Tecnología de Alimentos –ICTA– de la Universidad Nacional de Colombia. Con esta información se identificaron 465 empresas ganaderas productoras de canales óptimas (4 y 5 estrellas) y en 122 de ellas se recogió información tecnológica, productiva y económica; ello permitió seleccionar las 40 mejores empresas ganaderas de la región Caribe y el Magdalena Medio, ocho empresas por cada frigorífico. Se recolectaron muestras de tejido muscular (Longissimus dorsi) en tres canales por empresa ganadera a fin de evaluar la resistencia al corte (terneza) según la técnica de Warner Bratzler para un total de 120 muestras. Se encontraron diferencias estadísticas significativas (P&lt; 0,0001) de la fuerza de resistencia al corte con respecto al tipo genético utilizado y a la empresa muestreada; el promedio general de resistencia al corte fue de 4,81 ± 0,94 kgf (cv = 19,43%), siendo un factor de importancia la edad de sacrificio del animal. Se destacó la terneza de las muestras de carne de los animales cruzados de la raza Cebú con animales Bos taurus (Pardo Suizo) y criollos (Romosinuano), con 3,05 y 3,95 kgf, respectivamente. Además, se encontró mayor terneza de la carne cuando se ofrecía suplementación nutricional a los animales en forma de premezclas, con valores de resistencia al corte de 2,65 ± 0,33 kgf.

The effects of selection indices for sustainable hill sheep production on carcass composition and muscularity of lambs, measured using X-ray computed tomography

A multi-trait selection index designed to improve the overall economic performance of hill sheep, including both maternal and lamb traits, has been developed and tested in a selection experiment over 7 years. Two versions of the index were tested, with different economic weights applied to the traits, on two different hill farms: one version including maternal and growth traits; the other version with additional breeding goals of carcass weight, fatness and conformation scores. Responses to selection, using both versions of the index, suggest that improvements are being made in overall index score and lamb growth. This study investigated the indirect effects of these selection indices on lamb carcass composition and muscularity traits, as measured using X-ray computed tomography (CT) scanning. A total of 499 lambs from the two hill farms were CT scanned at weaning (approximately 120 days of age). Approximately half of the lambs from each farm were from the selection line (S, animals with highest index scores selected for breeding), while the other half were from a control line (C, animals with average index scores selected). Composition and muscularity traits were estimated on each lamb from CT data and differences between genetic lines investigated, within farm, using restricted maximum likelihood analyses, adjusting for either live weight or age. Results showed that the selection index without carcass traits produced lambs with carcass composition that was not significantly different to control lambs at a given live weight or age. Including carcass traits in the index resulted in lambs with no compositional differences (except for a slight increase in bone) at a set age compared with controls. At a given live weight however, selection lambs had less fat and lower carcass weights and killing-out percentage. Muscularity (3-D muscle shape) and muscle area shape (2-D) were not improved as a result of selection on either version of the index (including carcass weight and grades in the breeding goals or not) and, at a fixed live weight, muscularity in hind leg and lumbar regions tended to be higher in the C line. To accelerate changes in carcass composition and muscularity within the context of a multi-trait selection index for hill sheep, consideration should therefore be given to including objective CT-derived carcass traits in the index in addition to the Meat and Livestock Commission (MLC) carcass grades or ultrasound measurements.