• Asian-Australasian Journal of Animal Sciences
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• 제18권6호
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• pp.767-771
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• 2005

In order to understand the molecular basis of chicken heterosis in reproduction traits, mRNA differential display (DDRT-PCR) methods were used to analyze the differential gene expression of ovary tissue between hybrids and their parental lines in a 4${\times}$4 diallel cross, involving 4 chicken breeds, which were White Plymouth Rock (E), CAU Brown (D), Silkies (C) and White Leghorn (A). Total of 331 differential displayed cDNA bands from 1,161 were displayed in the 4${\times}$4 diallel cross combinations with 30 pairs of primers, which shows the differences of gene expression between hybrids and their parental lines were very obvious in quantity and quality. Seven types of differential expression patterns were found: Co-dominance expressed pattern (T1), under-expression of parental fragments in hybrids (T2), over-expression of parental fragments in hybrids (T3), hybrid-absence expressed pattern (T4), single parentspecific expressed pattern (T5), dominant expression fragments of single parent in hybrids (T6), hybrid-specific expressed pattern (T7). Correlation analysis indicated that there were significant correlations between the pattern of T3 and the heterosis percentage of egg number of 32-week and 42-week old chickens(p<0.01), while there were negative significant correlations between the pattern of T7 and the heterosis percentage of egg number of 32-week and 42 week-old birds (p<0.01).

• Asian-Australasian Journal of Animal Sciences
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• 제21권3호
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• pp.325-330
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• 2008

In order to understand the molecular mechanism of heterosis of reproduction traits in chickens, we used the quantitative real-time reverse transcriptional polymerase chain reaction (Quantitative real-time RT-PCR) technique to investigate the differential expression of estrogen receptor (ESR) and follicle stimulating hormone receptor (FSHR) genes in 32-week-old ovaries of inbred chickens and their hybrid offspring in $4{\times}4$ diallel crosses, which involved White Plymouth Rock (E), CAU Brown (D), Silkies (C) and White Leghorn (A). We found that there were significant differences in mRNA expression of ESR and FSHR genes not only between hybrids and their parental lines (p<0.01), but also among different crosses (p<0.01). Furthermore, positive correlations between differential expression of both ESR and FHSR in hybrids and heterosis percentages of 32-week-old and 42-week-old egg number traits were significant at p<0.05. Our results suggested that differential expression of ESR and FSHR genes in the ovaries of inbred chickens and their hybrids could play roles in the formation of heterosis of egg number traits to some extent.

• Asian-Australasian Journal of Animal Sciences
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• 제5권2호
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• pp.315-321
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• 1992

The utilization of feeding white sweet lupin (Lupinus angustifolius cv. Uniwhite) seeds supplemented with the limiting amino acids were investigated in day-old single comb White Leghorn male chicks. These were fed a commercial chick mash for the first 10 days and on a semi-synthetic protein-free diet for the next 6 days. For the subsequent 6 days of experimental feeding period, the birds were fed on the protein-free diet, basal diet containing 9.31% of lupin seed meal (LSM) protein, diets supplemented with methionine, methionine + tryptophan or methionine + tryptophan + lysine in the basal diet, and diet containing 9.84% of soybean meal (SBM) protein. When the LSM protein was supplemented with methionine, protein intake, body weight gain, protein efficiency ratio (PER) and net protein ratio (NPR) were increased (p<0.05). The birds excreted lower urinary nitrogen and fecal nitrogen per protein comsumption, had improved apparent (AD) and true (TD) digestibility but did not alter biological value (BV) of the protein. Metabolizability (MEn/GE) and heat production (HP) per MEn intake (HP/MEn) was lowered while energy retention (ER) was highered (p<0.05) compared with those of the basal diet. Also the body weight gain, PER, NPR and ER was increased but the BV and HP/MEn was lowered compared with those of the SBM protein. The results indicated that lupin seed supplemented with methionine increase body weight gain and energy rentention but did not alter biological value compared with those of lupin seed and soybean meal.

• 대한수의학회지
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• 제38권1호
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• pp.91-99
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• 1998

The immunogenetic analysis was performed to characterize the Korean native chickens (KNC) determined by monoclonal antibodies specific to chicken leukocyte differentiation antigens and flow cytometry. A total of 174 chickens including 58 KNC (black, brown and darkbrown colored), 77 foreign breed (Nagoya, White Reghorn, Rhode Island and Cornish) and 39 mixed breed (19 KNC with Nagoya and 20 KNC with Rhode Island) separately growing at Animal Science and Technology Institute were examined. The proportion of cells expressing MHC class II molecule (B-L in chicken) was significantly high in KNC. Proportion of CD4+ T helper cells was also higher in KNC and two mixed breed than that in foreign breed. However, proportion of CD8+ cells and TCR1 + (${\gamma}^{\delta}$ T cell receptor) cells was the lowest among the breed examined. Otherwise, those proportions were significantly high in White leghorn and two mixed breeds with two exclusive subpopulations. The two subpopulations were also typically shown in MHC class $II^+$ cells in KNC and one mixed breed, black-colored KNC with Nagoya. Although genotypic analysis was not pursued to characterize the immunogenetic properties of KNC, difference of phenotypic expression based on leukocyte differentiation molecules could be elucidated in KNC in this study.

• 한국가금학회지
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• 제35권2호
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• pp.171-176
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• 2008

본 시험은 동물 복지 차원에서 절식에 의한 강제 환우를 지양하고 사료를 급여하는 강제 환우 방법이 산란계의 생산성 및 난질에 미치는 영향을 알아보고자 60주령 White Leghorn 산란계 400수를 공시하여 34주간 실시하였다. 처리구는 관행적으로 절식한 환우구(C), 옥수수 단일 사료 급여(T1), 밀기울 단일 사료 급여(T2) 및 알팔파 단일 사료를 급여(T3)한 4처리로서, 처리구당 5반복, 반복당 20수씩 철제 케이지에 완전임의 배치하였다. 시험 결과 산란율 및 1일 산란량은 산란 후 $1{\sim}4$주간에만 T1에서 대조구에 비하여 유의적으로 감소하였으나(P<0.05), 전 시험 기간 동안에는 강제 환우 방법간에 차이를 보이지 않았다. 사료 섭취량은 $1{\sim}4$주에 T1에서 대조구에 비하여 통계적으로 감소하였으나(P<0.05), 전 시험 기간에는 처리구간에 차이가 없었다. 또한, 사료 요구율도 전 시험 기간 동안 처리구간에 유의적인 차이를 보이지 않았다. 난각 두께는 산란 후 10, 14주에 옥수수만을 급여한 T1구가 대조구에 비하여 유의적으로 개선되었으나(P<0.05), 26주에는 옥수수(T1)와 밀기울(T2)만을 급여한 처리구가 대조구에 비해 유의적으로 감소하였다(P<0.05). 난각 강도와 호우 유니트는 환우 방법에 따른 차이를 보이지 않았다. 난황색은 6주에 T1구와 T2구가 대조구에 비하여 유의적으로 감소하였으나(P<0.05), 18주에는 T1구와 T2구가 대조구나 T3구에 비하여 유의적으로 높았다(P<0.05). 시험 결과 사료 급여와 절식을 이용한 강제 환우 방법간에 생산성에서는 커다란 차이를 보이지 않았으며, 난질에서도 차이를 보이지는 않았다. 또한 사료 급여를 이용한 강제 환우에서는 알팔파만을 단독으로 급이한 강제 환우 방법이 옥수수나 밀기울을 급여한 강제 환우 방법보다는 생산성에서 통계적으로 유의차는 보이지 않았으나 우수한 경향을 보였다.

• Asian-Australasian Journal of Animal Sciences
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• 제16권10호
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• pp.1406-1410
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• 2003

The studies were based on the RAPD fingerprinting for the species identification of animals. The genomic DNA samples of ostriches, Taiwan local chickens, Aboracres broilers, Leghorn chickens, quails, doves, emus, Beltville small white turkeys, pheasants, Chinese geese, mule ducks, Holstein cattle and Landrace pigs were amplified with random primers by RAPD-PCR for fingerprinting. The results showed that the varied band patterns of DNA fingerprints were generated from templates depending on the kinds of primers or animal species. The same primer applied to the same breed, all of the main bands are similar, but which were different among species. In order to try to identify the species from the mixture of meat by RAPD fingerprinting, the meat of ostrich and cattle was mixed in different ratios for this study. The results showed that it could be easily and precisely distinguished according to the band distribution of RAPD patterns.

• Asian-Australasian Journal of Animal Sciences
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• 제1권3호
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• pp.173-178
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• 1988

To study the effects of utilizing extruded full fat soybean (FFS) in layer diets, 300 White Leghorn pullets were put in trial divided into 5 treatments; control (commercial soybean meal as protein source), FFS 50% (replacing 50% of soybean meal with FFS), FFS 100% (replacing all amount of soybean meal with FFS), soybean oil and tallow added treatment. Each treatment consisted of 5 replicates of 12 birds. Egg production and feed efficiency from hens fed control diet were significantly lower than from hens fed the other diets. Significant differences in egg production and feed efficiency were found between the control and the other treatments. Cholesterol concentration of serum and egg yolk were not affected by any dietary treatment. Feeding extruded full fat soybean did not cause pancreatic hypertrophy nor change in mortality. There was an indication that linoleic acid (C18:2), linolenic acid (C18:3) and iodine contents increased in the thigh and egg yolk lipid of the groups fed FFS or soybean soybean can serve as effective protein source for layer diets if economically justified.

• Asian-Australasian Journal of Animal Sciences
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• 제5권4호
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• pp.741-746
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• 1992

The effects of 5%, 10%, 15% and 20% dietary cellulose levels on the nutrient utilization in chickens were investigated. Four experimental diets were alternatively given to 8 colostomized White Leghorn cockerels to make a $4{\times}4$ Latin-square design. The diets of 70 g.day were force-fed once a day, and water was given freely. The digestibilities of DM and energy increased linearly with the increase in dietary cellulose level. The digestibilities of ether extract and nitrogen-free extract were not so much influenced by the dietary cellulose level. The digestibility of acid detergent fiber was very low and not influenced by the dietary cellulose level. The digestibility of neutral detergent fiber was not different among the diets containing 5%-15% cellulose, but that of the 20% cellulose diet was diminished. This might be due to the reduction of hemicellulose digestibility. True digestibility and biological value of protein were also not influenced by the dietary cellulose level from 5% to 20%. In conclusion, no ill-effect was found even when the chicken was fed a diet containing 20% of cellulose.

• Asian-Australasian Journal of Animal Sciences
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• 제24권5호
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• pp.603-609
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• 2011

Telomeres are special structures at the ends of eukaryotic chromosomes. Vertebrate telomeres consist of tandem repeats of conserved TTAGGG sequence and associated proteins. Birds are interesting models for molecular studies on aging and cellular senescence because of their slow aging rates and longer life spans for their body size. In this longitudinal study, we explored the possibility of using telomeres as an age-marker to predict age in Single Comb White Leghorn layer chickens. We quantified the relative amount of telomeric DNA in isolated peripheral blood lymphocytes by the Quantitative Fluorescence in situ Hybridization technique on interphase nuclei (IQ FISH) using telomere-specific DNA probes. We found that the amount of telomeric DNA (ATD) reduced significantly with an increase in chronological age of the chicken. Especially, the telomere shortening rates are greatly increased in growing individuals compared to laying and old-aged individuals. Therefore, using the ATD values obtained by IQ FISH we established the possibility of age prediction in chickens based on the telomere theory of aging. By regression analysis of the ATD values at each age interval, we formulated an equation to predict the age of chickens. In conclusion, the telomeric DNA values by IQ FISH analyses can be used as an effective age-marker in predicting the chronological age of chickens. The study has implications in the breeding and population genetics of poultry, especially the reproductive potential.

• 한국가금학회지
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• 제23권4호
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• pp.177-183
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• 1996

This study was conducted to analyze genetic characteristics of Korean Native Chicken three lines classified on the basis of the feather color and appearance (Red, Yellow, and Black) using DNA fingerprinting method. To estimate the genetic relatedness among breeds and similarities within breeds, we collected blood samples from Korean Native Chicken (KNC), Rhode Island Red (RIR), White Leghorn (WL), and Cornish(CN) and obtained genomic DNA from the blood of 10 individuals randomly selected within the breeds and lines. The genomic DNA samples were digested with restriction enzymes (Hinf J, Hae Ill) and hybridized with various probes (Jeffreys' probes 33.15, 33.6 and M13) after Southern transfer. Genetic similarities within breeds were characterized by band sharing (BS) value, estimated by the DFP band pattern between the pair of lanes. BS values within WL, RIR, and KNC were 0.82, 0.70 and 0.56, respectively. Relative genetic diversity (BS value) of KNC was higher than those two breeds (WL, RIR). Estimation of genetic similarity between KNC lines and control breed (RIR) was 0.32, whereas similarity within KNC lines (6 groups) was 0.50. In this analysis, KNC was showed to have a highly genetic diver-sity at the DNA level, and to be closer in genetic distance to RIR (0.67) than any other breeds.