• Korean Journal of Poultry Science
• /
• v.45 no.2
• /
• pp.109-118
• /
• 2018

A great progress in genetic selection, nutrition and management practices has contributed to the improved growth rate of broilers and egg production in laying hens. For the increased productivity of modern poultry, a healthy chicken liver needs to cope with the increased metabolic demands. The liver is the major site of de novo fatty acid synthesis; therefore, hepatic lipogenesis is crucial for producing better quality meat and eggs. When de novo lipogenesis exceeds the capacity of lipid metabolism and secretion, large amounts of lipids accumulate in the liver of broilers, leading to a fatty liver. Upon onset of egg-laying in hens, lipids including free fatty acids, triglycerides, and phospholipids are dramatically increased in blood plasma for the synthesis of yolk precursors in oocytes. Productive hens with fatty liver often have hemorrhagic syndrome and sudden death due to the heavy demands of yolk synthesis, which burdens the liver. Understanding the lipid metabolism and hepatic lipid disorders is a key point in the improvement of the growth and production of chickens. This review focuses on the recent studies on lipid metabolism, the hepatic lipid disorders, and the prevention or reduction of fatty liver in poultry.

• KOREAN POULTRY JOURNAL
• /
• v.27 no.9 s.311
• /
• pp.163-169
• /
• 1995

본 연구는 우리나라 고유의 재래닭을 수집하여 유전적 특성에 따른 계통을 육성하고 그 능력을 검정하므로서 재래닭 육용화사업의 기초계로 활용하기 위하여 1994년 6월 10일 수집된 종란의 입란을 시작으로 1994년 7월 1일 재래닭 기초세대 3계통 2,677수와 로드종 411수 및 나고야종 234수, 총 3,322수를 입식하여 능력검정을 실시하였으며 26주령까지의 중간성적을 요약하면 다음과 같다. (1)수정율 재래닭 평균의 $90.28{\%}$로 로드종이나 나고야종보다 높았으며 그 중 황갈색계통이 $91.01{\%}$ 로 가장 높았다. (2)부화율은 재래닭 평균이 $68.68{\%}$로 그리높은 편은 아니었으나 로드종이나 나고야종보다는 높았으며 황갈색계통이$69.46{\%}$로 그 중 가장 높았다. (3)육추율은 재래닭 평균이 $96.64{\%}$로 로드종과 비슷한 성적을 보였으며 흑색계통이 다소 낮았고 적갈색 및 황갈색계통은 $97.58{\%}$,$97.94{\%}$로 높았다. (4)육성율은 재래닭 평균이 $98.61{\%}$로 로드종과 비슷하였으며 계통간에도 별 차이없이 고른 성적을 보였다. (5)육성기 발육성적은 4주, 8주, 12주 및 16주 체중에서 재래닭 평균이 각각 235.31g, 640.16g, 1,002.47g 및 1,242.43g 으로 나타났으며 전기간에 걸쳐 흑색계통이 비교적 높은 경향이었다. (6)시산일령은 재래닭 평균이 154.15일로서 로드종보다는 약 12일 정도 늦었으며 재래닭 계통간에는 서로 별 차이를 보이지 않았다. (7)시산시난중은 재래닭 평균이 35.15g으로 로드종에 비해서는 약 35.83g 으로 타계통보다 다소 무거웠다.

• Monthly Korean Chicken
• /
• v.20 no.3
• /
• pp.58-59
• /
• 2014

당근과 양파, 토마토, 양배추 등이 큼직큼직하게 들어가 있는 닭고기 수프. 재료 자체의 향을 최대한 살릴 수 있도록 소금 이외의 간은 거의 하지 않는다. 속이 든든해지는 고단백 요리.

• Korean Journal of Poultry Science
• /
• v.38 no.2
• /
• pp.81-87
• /
• 2011

The study was conducted to select and optimize microsatellite (MS) markers for evaluate Korean Native Chicken (KNC) breeds in order to provide standard for the classification and breed definition of the indigenous breeds. The study also aimed to characterize and classify each KNC populations for inventory and management of avian genetic resources. A total of 462 chickens from 11 populations of chicken breeds including eight KNC breeds and three commercial chicken breeds were analyzed with 19 MS markers. KNC breeds, especially Long-Tail Chicken breeds, formed separate cluster from those commercial chicken breeds. Genetic distances between KNC populations (0.11~0.18) were relatively shorter. Genetic uniformity of KNC (except KNCR breed) (0.86~0.88) were higher than that of commercial breeds (except Cornish) (0.95~0.97). On the other hand, genetic uniformity of KNC Long Tail (KNCLT) were relatively higher (0.91~0.97). The result can be used to evaluate and manage animal genetic resources at national scale.

• Monthly Korean Chicken
• /
• v.16 no.10
• /
• pp.82-83
• /
• 2010

흔히 닭똥집이라고 불리우는 근위(닭모래집)는 무슨 영양가가 있을까 싶지만 지방질이 거의 없고 단백질 함유율이 높으며, 비타민 B와 철분이 많이 들어있어 다이어트에도 좋습니다. 2004년 말 매운맛 열풍이 프랜차이즈 업계를 강타하면서 닭발의 인기는 닭발전문점이 생길 정도로 높아졌습니다. 과거에는 모양이 흉측해 먹기를 꺼려했지만 최근에는 닭발 애호가까지 생길 정도로 닭발의 인기는 여전합니다. 찬바람이 옷깃을 여미게 하는 가을에는 닭 근위와 닭발 구이를 안주 삼아 가족 간 이야기 꽃을 피워보는 건 어떨까요?

• Korean Journal of Food Science and Technology
• /
• v.23 no.1
• /
• pp.25-30
• /
• 1991

Chicken liver was enzymatically hydrolyzed with an alkaline protease and determined the optimal conditions of reaction temperature and time, pH and enzyme to substrate ratio(E/S ratio) for possible utilization as a protein supplementary ingredient. The functional properties of hydolysate measured were water and oil absorption capacity, emulsifying activity and viscosity and sensory properties were also evaluated. It was found that hydrolysis at $60^{\circ}C$ and pH 8.0 were most effective and the degree of hydrolysis increased with increasing E/S ratio. A decrease in water and oil absorption capacity and an increase in viscosity were found during hydrolysis. The lowest emulsifying activity and highest water absorption were measured for 1/2 hour-hydrolysate and little difference was found for those treated more than 1 hour. The sensory characteristics of odor showed no significant difference among the chicken liver hydrolysates while the brightness increased and red decreased significantly(p<0.01) as the hydrolysis proceeded.

• Korean Journal of Poultry Science
• /
• v.30 no.2
• /
• pp.129-134
• /
• 2003

This study was conducted to investigate the effects of liquid rooster semen on reproductive ability in chicken. Raw and diluted semens were stored at 5$^{\circ}C$ cold temperature for 6, 30, and 54 hours after semen collection. There was no statistically difference in sperm motility throughout the 6 hours period of storage among raw semen and diluted semen groups with skim milk glucose solution (SM), egg yolk glucose solution (EY), and saline. But there was decrease in those throughout the period of 30 and 54 hours of storage. Sperm motility and normal sperm for the period of 30 and 54 hours of storage were significantly better in SM and EY diluted groups (P<0.05). Fertilization rates of rooster semen diluted with SM were 90.77, 87.70, and 59.46% for 6, 30, and 54 hours stored groups, respectively, those proved to be higher in SM-diluted group than other groups.

• Korean Journal of Poultry Science
• /
• v.20 no.4
• /
• pp.177-188
• /
• 1993

This study was performed to find out the reasonable sexing methods In the chicken, obtain the basic information for the mechanisms related to chicken sexual differentiation and identify the genes which known to involved in chicken sex differentiation. The chromosome analysis of chicken embryonic fibroblast was a simple method to determine sex of chicken by means of Z and W chromosome identification. The bands of female chicken genomic DNA digested with Xho Ⅰ and Eco RI restriction endonuclease showed to be useful in direct sex determination and these repetitive sequences of Xho Ⅰ and Eco RI families were proposed to be very homologous in their sequences by colony hybridization analysis. Seven of 150 random primers were selected to amplify the W chromosome-specific band by using arbitrary primed PCR and three of them were useful to identify the sex of chicken. To identify the sex differentiation genes in the chicken, PCR for the amplification of ZFY and SRY sequences was performed. ZFY and SRY sequences were amplified successfully in the chicken genome, implying that chicken genome might have the sex-related conserved sequences similar to mammalian ones. The PCR products of ZFY amplification were the same in both sexes, suggesting that these sequences may be located on autosome or Z chromosome. The profile of PCR amplification for SRY sequences showed variation between sexes, but this result was not enough to specify whether the SRY gene in chicken is on the autosome or sex chromosome.

• Proceedings of the Korea Society of Poultry Science Conference
• /
• 2004.11a
• /
• pp.13-15
• /
• 2004

Telomeres are the end of chromosomes and consist of a tandem repeat sequence of (TTAGGG)n and associated proteins. Telomeres are essential for chromosome stability and are related with cell senescence and apoptosis. This study was carried out to analyze the amount of telomeric DNA of chicken lymphocytes, which is to considered as bio-marker. The amount of telomeric DNA of lymphocytes in Korean Native Chicken and White Leghorn was analyzed by quantitative-fluorescence in situ hybridization (Q-FISH) technique using the chicken telomeric DNA probe. Telomere quantifies were compared among breeds, ages and sex, and the relationship between the amount of telomeres and their productive trait was also analyzed. Comparing the amount of telomeric DNA on lymphocytes during growing period, the amount of telomeres was gradually decreased as growing older. The telomere quantity was also significantly different in breeds and sex. Estimating correlation coefficient, the amount of telomeres was positively correlated to sexual maturity and body weight but negatively correlated to hen day egg production and egg weight. These results implicate the telomere quantity is considered as an individual bio-marker.

• Korean Journal of Poultry Science
• /
• v.48 no.4
• /
• pp.177-184
• /
• 2021

Sex identification in day-old chicks is essential in the poultry industry. Currently, the feather-sexing using a sex-linked inheritance is a chick sexing method used extensively in the poultry industry. For chicks produced by feather-sexing, all females are early-feathering (EF) chicks and all males are late-feathering (LF) chicks. Therefore, investigating the effects of EF and LF phenotypes on production traits of chickens is critical. The purpose of this study was to analyze and compare the production performance between EF and LF chickens in Korean native commercial chickens. The results showed that the survival rate of the EF chickens was significantly higher than that of the LF chickens, from hatching to 12 weeks of age (P<0.05), with the highest difference observed in females. However, no significant difference was observed in body weight between the EF and LF chickens at almost all ages. In addition, no significant difference was observed between in feed utility, such as average daily feed intake and feed conversion ratio, between the EF and LF groups. In conclusion, although the survival rate of early-feathering chickens was superior to that of late-feathering chickens, no significant difference was observed in growth performance and feed utility among Korean native chickens. The results suggest that production capacity is not influenced by feathering type in the establishment of a breeder structure and production system for feather-sexing Korean native chickens, which is valuable for the practical application of feather-sexing in the poultry industry.