• Korean Journal of Poultry Science
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• v.40 no.2
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• pp.121-127
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• 2013

This work was carried to evaluate production efficiency factor, carcass yield and meat quality with weeks of Large-type Korean native ducks. Korean native ducks (n = 90) from National Institute of Animal Science (RDA, Korea) were used in this work. Ninety ducks were divided into 6 groups (15 birds/group) and were fed with meat-type duck diets for 8 wk old. When ducks grew at specific wk (6, 7 and 8 weeks), 2 ducks per group were slaughtered at 6, 7 and 8 wk old. Production efficiency factor, carcass yield, partial meat and meat quality were researched in this work. There was no significant difference on livability with weeks, but body weight at 7 and 8 wk old was higher than that at 6 wk old (P<0.05). Feed conversion ratio at 6, 7 and 8 wk old were 2.25, 2.69 and 3.21, respectively, so there was significant difference with weeks (P<0.05). Production efficiency factor at 6, 7 and 8 wk old were 256.6, 199.8 and 153.0, respectively, so there was significant difference with weeks (P<0.05). Carcass yield at 8 wk old was higher than that at 6 and 7 wk old as 73.5% (P<0.05). Lightness at 6, 7 and 8 wk were 41.8, 39.0 and 38.1, respectively, and that at 6 wk old was the higher than other weeks (P<0.05). There was no significant difference on redness at 6, 7, and 8 wk old (P>0.05) and yellowness at 8 wk old was higher compared to other weeks (P<0.05). Cooking loss was the highest at 6 wk old as 31.6%, but water holding capacity was the highest at 8 wk old (P<0.05). There was no significant difference on shear force among weeks. pH at 6 wk old was the lower than that of other weeks as 5.84. Moisture content significantly decreased with weeks (P<0.05) and fat content at 8 wk was the highest as 1.88% (P<0.05). Protein content significantly increased with weeks until 20.9% at the age of 8 wk (P<0.05). Ash content at 7 and 8 wk old was the higher than that at 6 wk old (P<0.05). There was no significant difference on juiciness, tenderness, and flavor with weeks. Finally, these results may provide that shipping time at 7 wk old preferred to that at 6 and 7 wk old, but further research was needed because of deficiency of data.

• Korean Journal of Poultry Science
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• v.40 no.4
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• pp.351-359
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• 2013

This study was undertaken to assess dietary crude protein (CP) and amino acid (AA) concentrations for growth performance and carcass characteristics in Korean native ducks. In a $2{\times}3$ factorial arrangement, 1-d-old Korean native male ducks were allotted to 6 dietary treatments in a completely randomized design. Experimental diets contained 23 or 21% CP with 1.31/1.09, 1.21/1.00, 1.11/0.91 and 1.11/0.91, 1.02/0.83, 0.92/0.75 AA (Lysine/Total sulfur amino acid, Lysine/TSAA), respectively, from 0 to 3 wk of age. From 4 to 8 wk of age, experimental diets had 19 or 17% of diet; each contained 1.00/0.79, 0.94/0.75, 0.88/0.71 and 0.88/0.71, 0.82/0.67, 0.76/0.63 AA (Lysine/TSAA), respectively. Each dietary treatment has 6 replicates and feed and water were provided ad libitum. Body weight (BW), feed intake and uniformity were measured at 3 wk and 8 wk and carcass characteristics were evaluated at 8 wk of age. As CP increased from 21 to 23%, the BW and BW gain significantly increased (P<0.05) during 0 to 3 wk of age. From 4 to 8 wk of age, BW, feed intake, BW gain, feed conversion rations (FCR) and uniformity were not different (P>0.05) between treatments. Carcass yield and relative weights of liver, spleen, right breast and leg per 100 of BW were not different (P>0.05) between treatments. The meat color, shear force value, cooking loss and pH were not affected by dietary treatments (P<0.05). Korean native ducks require relatively low levels of dietary CP and AA for late growth and carcass yield due to low daily weight gain. This suggests the possible differences in CP and AA needs between Korean native ducks and commercial breeds from foreign breeding companies, especially late growth stage.

• Journal of Animal Science and Technology
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• v.44 no.3
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• pp.315-326
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• 2002

This study was conducted to examine the effects of Red clay(Hwangto) as feed additives with 26 Hanwoo steers at two regions for 540 days from six to 24 months of age on feed efficiency, meat quantity and meat quality. Feeding trial 1 was conducted with two treatment groups by five heads/treatment which were T1(Control) and T2(Control+ad libitum Hwangto) at National Livestock Research Institute. Feeding trial 2 was conducted with four treatment groups by four heads/treatment which were T1(Control), T2(Control+2% Hwangto), T3(Control+5% Hwangto) and T4(Control+ad libitum Hwangto) at a private Hanwoo breeding farm. In feeding trial 1, average daily gains by growing, fattening, finishing and over-all periods were 0.572, 0.866, 0.869 and 0.769kg in T1, and 0.537, 0.904, 0.857 and 0.766kg in T2, respectively. Average daily gain for growing and finishing period was high in T1 but in T2 for fattening period, which were not statistically significant. Also concentrates and TDN intakes per kg gains were not statistically significant by treatments. In carcass characteristic, dressed carcass and red meat percentage were high in T1 but in T2 for retailed cut percentage without significant difference. The yield index and shear force was 69 and 70, 4.4 and 6.1 kg/$cm^2$ in T1 and T2, respectively. In palatability traits, the panel test scores of juiciness, tenderness and flavor were 4.08 and 4.64, 3.42 and 3.96, 4.58 and 4.80 in T1 and T2, respectively. which showed a tendency to improvement in Hwangto feeding groups. In feeding trial 2, the range of average daily gains were 0.656(T6) to 0.772(T3), 0.937(T6) to 1.009(T5), 0.592(T3) to 0.675kg(T6) in growing, fattening and finishing period, respectively. Although it was high in T3, T5 and T6 at growing, fattening and finishing period, respectively, it was not significantly different by treatments. The ranges of concentrates and TDN intakes per kg gains were 8.71 to 9.50(average 9.05) and 7.52 to 7.64kg(average 7.55kg), they all were lower in Hwangto feeding groups than in control about 4.5 to 8.3% and 1.2 to 1.6%, respectively. In carcass characteristics, back-fat thickness, loin eye muscle area and yield index were not difference by treatments, but marbling scores were high in T5 and T6 than in percent. Summarizing above results, it may be concluded that the use of unprocessed Hwangto as feed additives for growing-fattening steers seems to improve meat quality but not red meat quantity and feed efficiency, and may be required to feed ad libitum during the finishing period.

• Food Science of Animal Resources
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• v.33 no.1
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• pp.125-132
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• 2013

In the present study, to determine the effects of terminal sire strains, carcass characteristics, yields of retail cut, and meat quality of 425 pigs were examined. Terminal sires were divided into five strains (D1, D2, B1, B2, and BD) based on the countries of origin and breeds. The strains D1 and D2 showed high grade 1+ appearance ratios and strains B1, B2, and D1 showed high appearance ratios of carcass yield grade A. As for the real retail cut yields of meat, strain D1 showed large real retail cut yields of meat in shoulder, rib, fore leg, loin, belly, tenderloin and hind leg. Moisture contents were significantly higher in strain B1, and protein and fat contents were significantly higher for strain D1 than in the other strains (p<0.05). Shear force values were significantly higher for strain B1 than in the other strains (p<0.05). For meat color properties, the lightness were significantly higher in strains D1, D2, and BD, and the yellowness were significantly higher in strains D1, D2, and BD relative to the other strains (p<0.05). In sensory evaluation, drip of strains D1 and D2 were significantly lower while marbling and overall acceptability were significantly higher in the other four strains (p<0.05). Therefore, when considering the results of the present study comprehensively, using strains D1 and D2 that showed high grade 1+ appearance ratios, large real retail cut yields of belly, significantly higher lightness and sensory evaluation will be helpful to the incomes of producers and farm households.

• Journal of Animal Science and Technology
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• v.47 no.6
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• pp.1059-1066
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• 2005

The objective of this study was to investigate the physico-chemical characteristics of chicken breast surimi processed by four times washing (C) and adjustment to pH 3.0 (T1) and pH 11.0 (T2). Water, crude protein, myofibrillar protein and yield of the treatment C were lower compared to other two treatments. Crude fat of T2 was higher than other two treatments. pH, WHC, breaking force and deformation were not different among the treatments. Shear force of T2 was the highest, followed by T1 and C. L* of T2 and a* of T1 were lower than other two treatments. b* of C was the highest, while T2 was the lowest. Brittleness and hardness in textural properties were not different among the treatments. Cohesiveness of T1 was the lowest among three treatments. Springiness and chewiness of T1 and T2 were higher than those of treatment C, respectively. Gumminess of T2 were higher compared to C and T1. Appearance and flavor in sensory evaluation were the highest in T1 and the lowest in C among three treatments. Color, aroma, juiciness, tenderness and overall acceptability were not different among the treatments. In conclusion, physico-chemical quality of chicken breast surimi was the highest in T2 among three treatments.

• Journal of Animal Science and Technology
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• v.54 no.2
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• pp.111-124
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• 2012

Feeding trial was conducted with 80 Hanwoo steers (7.5 months of age, 204.4 kg body weight) for 680 days from growing period to late fattening period to examine the feeding value of whole crop barley silage TMR (BS-TMR) and whole crop rye silage TMR (RS-TMR) on body gain, feed cost, slaughter characteristics and quality characteristics of $longissimus$ $dorsi$ muscle. Dietary treatments were conventional separate feeding of concentrate and rice straw (control), feeding BS TMR up to middle fattening period and same diet as for control during late fattening period (BS-TMR I), feeding BS-TMR for whole experimental period (BS-TMR II), feeding RS TMR up to middle fattening period and same diet as for control during late fattening period (RS-TMR I) and RS TMR for whole experimental period (RS-TMR II). Sixteen castrated calves were assigned to each treatment (4 pens, 4 heads per pen). Pens in each treatment were randomly distributed. Feeding both BS silage TMR and RS silage TMR slightly increased body gain of Hanwoo steers at the stages of growing and early fattening, and increased (P<0.0001) at middle fattening compared to feeding control diet while control diet tended to increase body gain at late fattening stage compared to feeding BS-TMR I, BS-TMR II and RS-TMR I diets. Total body gain was slightly increased in Hanwoo steers fed both I and II for BS and RS TMR compared to that in control diet. Feed cost per kg gain per head was relatively low in the Hanwoo steers fed silage TMRs to that fed control diet. Carcass weight, back fat thickness and $longissimus$ $dorsi$ area of Hanwoo steers tended to increase but lowered (P<0.047) yield index by feeding silage TMRs. Feeding BS TMR slightly decreased marbling score but no difference was found in the number of head over grade 1 between diets. Control diet tended to improve yield grade compared to silage TMRs. Chemical composition, water holding capacity, drip loss, cooking loss and pH, color and fatty acid composition of $longissimus$ $dorsi$ were not affected by experimental diets and feeding duration of silage TMRs. Shear force, however, was increased (P<0.046) by silage TMRs without difference between them compared to control diet. Based on the results of the current study, BS TMR and RS TMR could improve body gain and reduce feed cost without deteriorating meat quality compared to separate feeding of concentrate and rice straw. Overall feeding value was similar between BS TMR and RS TMR.

• Journal of Animal Science and Technology
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• v.51 no.1
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• pp.53-60
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• 2009

Thirty one Hanwoo steers were used in a completely randomized design experiment to see the effects of concentrate feeding method (group vs. individual feeding) and age at slaughter (26 vs. 28 months of age) on growth performance, feed intake and carcass characteristics. Steers were randomly assigned to one of four groups, G26 (group feeding slaughtered at 26 months of age), G28 (group feeding slaughtered at 28 months of age), I26 (individual feeding slaughtered at 26 months of age) or I28 (individual feeding slaughtered at 28 months of age). Amount of concentrate were restricted to 1.5% of BW for the growing period and 1.8% of BW for the early fattening period in both groups. For the late fattening period, concentrate were given ad libitum for G26 and G28, but were given up to 1.7% of BW for I26 and I28. Average daily gains were higher in individual feeding groups (I26 and I28) than those in group feeding groups (G26 and G28) for the early fattening period (p<0.05). ADGs were higher in group feeding groups than those in individual feeding groups (p<0.05). Concentrate intake in individual feeding groups tended to be higher compared to that in group feeding groups for the early fattening period, but tended to be higher in group feeding groups compared to that in individual feeding groups for the late fattening period. Feeding method or slaughter age had no significant effects on carcass characteristics, yield grade and quality grade. Shear force and tenderness of longissmus muscle were higher in groups slaughtered at 28 months of age than in groups slaughtered at 26 months of age (p<0.05). Feeding method or slaughter age had no effects on cooking loss, water holding capacity, juiciness, flavor, moisture, protein and fat of longissmus muscle.

• Journal of Bio-Environment Control
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• v.22 no.3
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• pp.284-290
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• 2013

This study analyzed the geometric, compressive, cutting and friction properties of oriental melons in order to design a gripper capable of soft handling and a cutter for cutting oriental melon vine among the end effector of oriental melon as a preliminary step for developing the end effector of the robot capable of harvesting oriental melons in protected cultivation. As a result, the average length, diameter at the midpoint, weight, volume and roundness of the oriental melons were 108 mm, 70 mm, 188 g, 333 mL and 3.8 mm. Nonlinear regression analysis was performed on the equation $W=L^a{\times}D_2^b$ with variation of the length (L) and diameter (D2) of the weight (W) of the oriental melons. As a result, it was shown that there was a correlation between a of 2.0279 and b of -0.9998 as a constant value. The average diameter of the oriental melon vine was 3.8 mm, and most vines were distributed within a radius of 5 mm from the center. The average yield value, compressive strength and hardness of the oriental melons were $36.5N/cm^2$, $185.7N/cm^2$ and $636.7N/cm^2$, respectively. The average cutting force and shear strength of the oriental melon vines were $2.87{\times}10^{-2}\;N$ and $5.60N/cm^2$, respectively. The maximum friction coefficient of the oriental melons was rubber of 0.609, followed by aluminium of 0.393, stainless steel of 0.177 and teflon of 0.079. It was considered possible to apply it to the size of the gripper and cutter, turning radius, dynamics of drive motor and selection of materials and their quality in light of the position error and safety factor according to the movement when designing end effector based on the analyzed data.

• Korean Journal of Poultry Science
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• v.31 no.3
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• pp.165-170
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• 2004

The objective of this study was to evaluate the carcass and meat quality of broiler chicken when slaughtered after treating with different source of grain(T1, 100% corn; T2, 50% corn + 50% brown rice; T3, 100% brown rice) in broiler diet. The carcass weight was decreased when feeding level of rice increased. The yield of breast was higher in T2(18.6%) than T1(17.3%) and T3(l7.9%). The L values(L *) and b values(b*) in meat color were decreased as the feeding level of rice increased when compared to T1(P < 0.05). Warner-Bratzler shear force(WBS) values were higher in T2 and T3 compared to T1. Cooking loss(%) was increased for T2(23.49%) and T3(24.50%) compared to T1(22.90%). In fatty acid composition, linoleic acid(C18:2, n6) contents were significantly lower in T2(31.89%) and T3(27.89%) when compared to TI(33.21%)(P < 0.05), and the total contents of unsaturated fatty acids(UFA) were 76.85%(T1), 77.22%(T2), or 75.49%(T3). The ratio of n6/n3 was decreased as the level of rice increased in the feed(T1 19.89%, T2 17.73%, and T3 17.01%). In conclusion, the meat quality was not significantly different between T1 and T2 from the results of carcass weight, meat color, WBS, and fatty acid composition; therefore, brown rice can be substituted for 50% of corn in the broiler diets.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.4
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• pp.250-257
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• 2019

This study was carried out to investigate the effect of mountain grazing on growth performance and carcass characteristics of Hanwoo steers. Thirty two Hanwoo steers were randomly assigned. Control were fed concentrate + forage until 30 month of age. Treatment1 were fed concentrate + forage after mountain grazing from 8 to 13 months. Treatment2 and 3 were fed concentrate + forage after mountain grazing from 8 to 17 months. Hanwoo steers on Treatment 1 and 2 were slaughtered at the same age (30 months) as the control, and Hanwoo steers on Treatment 3 were slaughtered at 31 months. The average daily gain (ADG) were higher in the control than in the other treatments during the growing period (p<0.05). Carcass back fat thickness was thicker in the TRT 3 and marbling score was higher in the TRT 1 than in the other treatments; however, the differences were not statistically significant. There was no difference in the meat composition and shear force of the longissimus muscle according to the mountain grazing. However, the yellowness (b) of fat colors were significantly lower in the control than in the TRT 1 and TRT 2 (p<0.05). The effect of grazing on fatty acid composition was not constant. In conclusion, mountain grazing could reduce meat color without affecting the growth and meat quality of Hanwoo steers, and further research on the quality, yield and intake of grassland would be needed.