• Korean Journal of Poultry Science
• /
• v.37 no.4
• /
• pp.415-421
• /
• 2010

This work was carried out to investigate chemical composition and meat quality of crossbred Korean native chickens (KNC). Ninety 1-d male chicks were used in this work and were divided into 4 groups as A: (KNC egg-meat type C strains $\times$ KNC meat type S strains) (female) $\times$ KNC meat type H strains (male), B: (KNC egg-meat type C strains $\times$ KNC meat type H strains) (female) $\times$ KNC meat type S strains (male), C: (KNC native R strains $\times$ KNC meat type S strains) (female) $\times$ KNC meat type H strains (male), D: (KNC native L strains $\times$ KNC meat type H strains) (female) $\times$ Ross broiler (male) strains. They were fed the broiler diets for 12 weeks at the flat house and twenty seven chickens were slaughtered at week 5 and 10. Chicken thigh and breast were weighed and physicochemical compositions and sensory characteristics were investigated. Physical compositions of meats have no difference among strains at 5 week, and B strains differed from other strains at 10 week (P<0.05). The pH, moisture, and collagen content of meat from B strains were lower than other strains at 5 week. Ash and collagen of A strains were the lowest at 10 week (P<0.05), but others have no difference among strains. In sensory test, juiciness of D strains was the highest at 5 week, and tenderness of B strains was the lowest at 10 week (P<0.05). In conclusion, the crossbreeding of KNC did not affect physical traits but affected chemical composition of the chicken meat slaughtered at 5 week.

• Korean Journal of Poultry Science
• /
• v.8 no.1
• /
• pp.1-5
• /
• 1981

In trying to predict the effect of genetics on the broiler in the year 2000, this is a relatively short period of time as far as broiler genetics in concerned. Modern broiler genetics started around 1945 and tremendous gains when made in past 35 years. Futher improvements on broiler will depend on the evolution and revolution: 1. Evolution: (1) Growth rate has been made 4-5% per year. (2) Feed conversion has improved approximately 1% per year. (3) Abdominal fat is becoming a major complaint in broiler. (4) Because of the changing life-style, broiler meat sales in the future will be more and more in cut-up form. (5) Breeding for stress resistance and selection for docile temperament can be important in order to funker improve fled efficiency. (6) In female parent stock, reproduction characteristics are in many can negatively correlated with the desired broiler traits. (7) Egg production and hatchability in moot commercial parent nod m at a fairly high level. (8) In male parent stock, the heavier and mon super-meat-type male lines are desired to Product better broilers. 2. Revolution: Trying to forecast revolutionary change in broiler genetics is highly speculative, as sudden change are aften unpredictable. (1) Species hybridization, such as a turkey-chicken cross (2) Biochemical tools, such as blood typing. (3) Mutation breeding by radiation or chemical mutagentia. (4) Broiler breeding would be to change the phenotypic appearance by single gene, such as naked, wingless. (5) Changes in production techniques. such as growing in cage or growing in filtered air positive pressure houses.

• Korean Journal of Poultry Science
• /
• v.31 no.4
• /
• pp.245-253
• /
• 2004

This study was conducted to investigate the effects of dietary yeast culture containing rPST on growth performances and the characteristics of body compositions in broiler chickens. A total of 460 Ross male broiler chicks aged 2-day-old were fed one of five experimental diets; Control(devoid of all), TI (with $0.1\%$ antibiotics; chlorotetracycline), T2 (with $0.1\%$ rPST-yeast culture), T3 (with $0.2\%$ rPST-yeast culture) or T4 (with $0.2\%$ SC yeast culture) for 6 weeks. Feed consumption and body weights were measured weekly. At week 5 of the experiment, 10 chicks were randomly selected and sacrificed. The relative weights of each organ and the chemical composition of edible meat were measured. The enzyme activity, total cholesterol, Ca and P were also determined. Tibial weight, bone strength and chemical composition were investigated. There were no significant differences in feed intake and feed conversion ratios among the treatments throughout the experimental period. Body weight gains tended to be increased by feeding of diets containing rPST-yeast culture. The relative weight of breast muscle in T3 group was significantly higher than that of the control (P<0.05). The moisture contents of breast meat in groups fed diets containing rPST-yeast culture or SC yeast culture were significantly increased as compared with those of the control and n. However, the contents of crude protein and ether extract were not affected by feeding of rPST-yeast culture. There were no significant differences in GOT, total cholesterol, Ca and P. The relative weight and strength and proximal composition of the tibia were also not affected by dietary treatments. These results indicated that dietary rPST-yeast culture may be a valuable alternative for optimizing growth performances, particularly for improving the yield of breast muscle.

• Korean Journal of Poultry Science
• /
• v.40 no.4
• /
• pp.315-325
• /
• 2013

In this study, the effects of Doenjang powder (DP : Korean traditional fermented soy bean paste) addition on the quality and shelf-life of chicken sausages during storage were evaluated. The chicken sausages were manufactured with 60% of chicken breast meat, 20% of chicken skin and other ingredients. The sausages were divided into four treatments according to DP addition level such as 0, 2, 5 and 8%. The sausages were vacuum packed and stored at a refrigerator ($5^{\circ}C$) for 4 weeks. pH of sausage was in creased with DP addition after 2 weeks storage (p<0.05). The addition of 2% and 5% DP decreased the lipid oxidation (TBARS) value (p<0.05) and addition of 8% DP seemed to promote the protein deterioration (VBN) over the storage (p<0.05). In the instrumental color, the chicken sausages with 5% and 8% DP showed higher redness and lower lightness value than sausage with 0 and 2% DP (p<0.05) over the storage. The hardness and gumminess of chicken sausages added with 5% DP were significantly lower than those of other treatments during the storage (p<0.05). The addition of DP detained the growth of aerobic and anaerobic bacteria counts after 2 week of storage (p<0.05), but no significant difference was found by DP addition level (p>0.05). In conclusion, 5% DP could be used as ingredient of chicken sausage to enhance sensory quality and retard lipid oxidation.

• Korean Journal of Poultry Science
• /
• v.44 no.1
• /
• pp.29-39
• /
• 2017

This study examined the effects of adding dried blood mixed with Macsumsuk to the feed of broiler chickens. The blood had been dried at $200^{\circ}C$ in an ultra-high-temperature injection system and mixed in a 70:30 proportion of blood meal to Macsumsuk. The experiment consisted of four treatment groups of 150 chickens each. The control group received common broiler feed only, while treatment groups T1, T2, and T3 received feed supplemented with 0.5, 1.0, and 3.0% of the blood meal/Macsumsuk mixture, respectively. The diets were fed for a total of 35 days. Compared with the controls, body weight gain was improved in groups T1 (1,621 g), T2 (1,749 g), and T3 (1,739 g) (1,621-1,749 g vs. 1,448.5 g, respectively) and feed efficiency increased (p<0.01). The carcass rate in group T3 was higher by 83.26% than that in the controls (75.96 %) (p<0.01). The water holding capacity (WHC) increased in groups T1 and T2 (62.27 and 63.80% respectively) compared with controls (p<0.01). The intestine length was longer in groups T1 and T2 (53.98-55.48) than in controls (45.81) (p<0.01). Adding 0.5-1.0% of the dried blood meal Macsumsuk supplement resulted in a significant reduction in the cholesterol content (39.28~47.34 mg/100 g) compared with the controls (50.44 mg/100 g) (p<0.001); furthermore, the proportions of fatty acids including oleic (C18:1n9), ${\gamma}-linoleic$ (C18:3n6), eicosenoic (C20:1n9), and arachidonic (C20:4n6) acids were significantly increased (p<0.01). Compared with controls, the proportion of unsaturated fatty acids (UFA), mono-unsaturated fatty acids (MUFA), and proportion of UFA / SFA in group T1 was (68.66 vs. 69.35%, 51.22 vs 52.00%, and 2.19 vs. 2.26%, respectively) (p<0.05). However, the amino acid content of cystine and methionine of the treatment group (0.43~0.57%) was significantly higher than that of controls (0.38~0.46%) (p<0.05). Overall, supplementing the feed with 0.5-1.0% of the mixture of blood meal Macsumsuk improved productivity by increasing weight gain and feed efficiency, improved meat quality by increasing the water-holding capacity and levels of unsaturated fatty acids, and improved meat color.

• Korean Journal of Poultry Science
• /
• v.44 no.1
• /
• pp.51-57
• /
• 2017

Subsequent to the introduction of the "Laws on Consumption Promotion of Livestock Products" in 2002, a mandatory check-off system for the egg industry was introduced in June 2009. Unlike other livestock products, the check-off on eggs is financed not from the sale of the egg-the end product-but from the spent hen. Variables such as the falling price of spent hens lead to a low financing rate; The present farm allotment rate of 14%, introduced in 2015, is much higher than the 0.2% to 0.3% check-off rate in other types of business, thus placing a huge burden on farms. When check-off is financed from the egg, it is expected that 6.5 billion won will be raised using a rate of 0.3% of sale proceeds, Therefore, it is urgent for the government to establish infrastructure to enable producers and merchants to do business through Grade & Packing centers. This can be achieved by the staged construction of local Grade & Packing centers. Check-off should continue to be financed from the present spent hen until this infrastructure is established, and an institutional strategy should be provided by the government to raise the financing rate accurately and transparently using statistical treatment of supply data for spent hens as a short-term alternative.

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

• Korean Journal of Poultry Science
• /
• v.38 no.2
• /
• pp.129-136
• /
• 2011

The objective of this study was to evaluate the effects of different levels of ${\alpha}$-tocopherol and selenium in broiler diets on performance and physicochemical properties of chicken thigh meat. A total of 360 broiler chicks divided into six groups were fed a basal diet (control) or basal diet supplemented with 50 IU ${\alpha}$-tocopherol/kg (T1), 100 IU ${\alpha}$-tocopherol/kg (T2), 200IU ${\alpha}$-tocopherol/kg (T3), 0.3 ppm selenium/kg (T4), and 100 IU ${\alpha}$-tocopherol/kg + 0.3 ppm selenium/kg (T5) for five weeks. Growth performance and proximate composition of chicken thigh meat were not influenced by all dietary treatments, except for crude fat, which was significantly lower in the treatment with ${\alpha}$-tocopherol or selenium, or both compared to control. The dietary ${\alpha}$-tocopherol and selenium supplementation had no significant effects on pH, CIE $L^*$ (lightness), and $b^*$ (yellowness) values but TBARS (thiobarbituric acid reactive substance) values were decreased (P<0.05) by the addition of ${\alpha}$-tocopherol and selenium. CIE $a^*$ (redness) values increased significantly with added ${\alpha}$-tocopherol and selenium relative to the control (P<0.05). Likewise, changes in fatty acid composition in chicken thigh meat with the dietary supplementations with ${\alpha}$-tocopherol, selenium and their combination significantly increased (P<0.05) unsaturated fatty acid, whereas saturated fatty acid were decreased. It was concluded that the addition of 200 IU ${\alpha}$-tocopherol (T3) and 100 IU of ${\alpha}$-tocopherol plus 0.3 ppm selenium (T5) were most effectiveness in the improvements in the lipid oxidative stability of chicken meat when compared to the control.

• Korean Journal of Poultry Science
• /
• v.39 no.3
• /
• pp.167-175
• /
• 2012

This study was undertaken to assess dietary CP and ME concentrations for optimum growth performance and carcass characteristics of Korean Native male ducks. In a $3{\times}3$ factorial arrangement, 1-d-old Korean Native male ducks were completely randomized design to experimental diets with 3,000, 2,900, and 2,800 kcal of ME/kg of diet; each contained 23, 22, and 21% CP, respectively, from 0 to 3 wk of age. From 4 to 8 wk of age, experimental diets had 3,100, 3,000, and 2,900 kcal of ME/kg of diet, and each contained 19, 18, and 17% CP, respectively. Each dietary treatment was replicated 4 times, and feed and water were provided ad libitum. Body weight, feed intake and uniformity were measured at 3 wk and 8 wk, and carcass characteristics were evaluated at 8 wk. As CP increased from 21 to 23 %, the body weight, BW gain and feed conversion ratios (FCR) linearly improved (P<0.01) during 0 to 3 wk of age. From 4 to 8 wk of age, the body weight, feed intake, BW gain, FCR and uniformity were not different (P>0.05). Carcass ratios of birds fed 3,000 kcal of ME/kg diets from 3 to 8 wk of age were quadratically increased significantly (P<0.01). As ME and CP increased, respectively, relative weight of liver weight per 100 g of BW was linearly decreased (P<0.01). Relative weights of left breast, thigh and drumstick weight per 100 of BW were not different (P>0.05). Also, breast meat color, pH, cooking loss and shear force were not different (P>0.05). Thus, diets with 2,800 kcal of ME/kg and 23% CP or with 2,900 kcal of ME/kg and 17% CP at 0 to 3 wk and 4 to 8 wk, respectively, were used more efficiently. However, diets with 3,000 kcal of ME/kg at 4 to 8 wk in carcass rate was quadratically increased.

• Korean Journal of Poultry Science
• /
• v.34 no.4
• /
• pp.237-243
• /
• 2007

The objective of this experiment was to investigate the feeding influence of Prunus memu by-products (PMB) on productivity, blood composition, meat quality and intestinal microflora in semi-broiler chicks. Four hundred one day old chicks(Hanhyup 3) were raised in the floor pen with five treatments(0, 0.5, 1.0 2.0 3.0%) of four replicate for ten weeks. Basal diets contained 3,000, 3,100, 3,100, 3,200 kcal/kg ME and 22, 21, 19, 17% CP, respectively. There were no different performance for the first two weeks, but showed significantly different weight gain, feed intake in PMB 2.0, 3.0% addition treatments compared with control from three to five weeks of age. Weight gain of birds fed 2.0% PMB was significantly higher from nine to 10 weeks of age than control(P<0.05). Total weight gain tended to increase in PMB 1.0, 2.0, 3.0% addition treatments. Feed intake also showed increase in PMB 2.0, 3.0% addition treatments, but there were no different feed conversion. Total protein, albumin, cholesterol, neutral fat, glucose was significantly decreased in PMB 0.5% addition treatments compared with control. There were no different physico-chemical characteristics in breast meat. The number of yeast was significantly improved in PMB 3.0% compared with control(P<0.05), but found no difference in number of E. coli between control and PMB treatments. ND titer of birds fed PMB was not statistically different, but tended to decrease as dietary PMB increased. As the result of this experiment, PMB would be available as a feed additives in semi-broiler chicks.