Poultry products including meat and eggs constitute a major protein source in the American diet and disease - causing pathogens represent major challenges to the poultry industry. More than 95 % of pathogens enter the host through the mucosal surfaces of the respiratory, digestive and reproductive tracts and over the past few decades, the two main mechanisms used to control diseases have been the use of vaccines and antibiotics. However, in the poultry industry, there are mounting concerns over the ability of current vaccines to adequately protect against emerging hyper - virulent strains of pathogens and a lack of suitable, cost effective adjuvants. Thorough investigation of the immunogenetic responses involved in host-pathogen interactions will lead to the development of new and effective strategies for improving poultry health, food safety and the economic viability of the US poultry industry. In this paper, I describe the development of immunogenomic and proteomic tools to fundamentally determine and characterize the immunological mechanisms of the avian host to economically significant mucosal pathogens such as Eimeria. Recent completion of poultry genome sequencing and the development of several tissue-specific cDNA libraries in chickens are facilitating the rapid application of functional immunogenomics in the poultry disease research. Furthermore, research involving functional genomics, immunology and bioinformatics is providing novel insights into the processes of disease and immunity to microbial pathogens at mucosal surfaces. In this presentation, a new strategy of global gene expression using avian macrophage (AMM) to characterize the multiple pathways related to the variable immune responses of the host to Eimeria is described. This functional immunogenomics approach will increase current understanding of how mucosal immunity to infectious agents operates, and how it may be enhanced to enable the rational development of new and effective strategies against coccidiosis and other mucosal pathogens.

The effects of dietary betaine on performance, blood compositions, hepatic amino acid concentrations and hormonal secretions were examined in laying hens. Egg production was significantly higher in birds fed the 16.5 % protein diet compared to those fed 14.5 % protein diet(p<0.05), whereas dietary supplementation of betaine did not show any significant effect. The high level of protein and betaine supplementation significantly improved egg weight, egg mass and feed conversion(p<0.05), while eggshell breaking strength, eggshell thickness and Haugh unit were not influenced by betaine and dietary protein levels. Supplemental betaine did not affect serum total protein, albumin and BUN concentration. However, uric acid concentration significantly increased in 600 ppm betaine-fed groups(p<0.05). Concentrations of most hepatic amino acid were influenced by increased protein feeding and dietary betaine supplementation. Hormone studies recorded significantly higher serum and hepatocyte IGF-I concentration in 600 and 1,200 ppm betaine treatments(p<0.05) compared to those of control group. IGF-I mRNA gene expression of hepatocytes revealed statistically correlated increase in 600 and 1,200 ppm betaine-fed groups compared to the controls(p<0.05). Serum IGFBP-3 concentration was significantly elevated in 600 ppm betaine treatments. However, the secretion of IGFBP-1 in hepatocyte of laying hens fed with 600 and 1,200 ppm of betaine showed a significant decrease compared to the control group(p<0.05). Results of these study show that dietary betaine supplementation affects protein and hormone metabolism in laying hens.

Tannins are phenolic compounds that precipitate proteins and composed of a very diverse group of oligomers and polymers. Tannins are potential biological antioxidants, which are widely believed to be an important line of defense against oxidative damage and may participate in the prevention of cancer and cardiovascular disease. Persimmon(Diospyros kaki L.) has been cultivated in East Asia and is a good source of nutritional antioxidant vitamins, carotenoids and tannins. In general persimmon peel was regarded as a waste matter, although based on recent studies, the peel contains more carotenoids and polyphenols than pulp. Several investigation conducted in experimental animals have reported that dietary persimmon fruit and peel effectively lowered the levels of plasma total cholesterol and LDL-cholesterol. We conducted experiments to investigate in vitro antioxidative activities of persimmon peel powder (PP) and its soluble tannin extract (ST) and their dietary effects on productive performances and physiological responses in poultry. The PP and ST exhibited in vitro antioxidative activity in SOD - like activity model. The yolk color and eggshell color were significantly improved by the addition of PP and ST into layer diets. The contents of total cholesterol, triacylglycerol and phospholipid of liver in the groups fed diets containing PP and ST tended to be reduce as compared with those of control. With adding of PP and ST, Haugh unit was increased after 7 and 14 days of storage. In conclusion, PP and ST can be used as valuable feed additives for reducing hepatic lipid contents without harmful effects on overall productive performances and physiological responses in laying hens.

As a bioreactor, bird has proved to be most efficient system for producing useful therapeutic proteins. More than half of the egg white protein content derives from the ovalbumin gene with four other proteins(lysozyme, ovomucoid, ovomucin and conalbumin) present at levels of 50 milligrams or greater. And the naturally sterile egg also contains egg white protein at high concentration allowing for a long shelf life of recombinant protein without loss in activity. In spite of these advantages, transgenic procedures for the bird have lagged far behind because of its complex process of fertilized egg and developmental differences. Recently, a system to transplant mouse testis cells from a fertile donor male to the seminiferous tubules of an infertile recipient male has been developed. Spermatogenesis is generated from transplanted cells, and recipients are capable of transmitting the donor haplotype to progeny. After transplantation, primitive donor spermatogonia migrate to the basement membrane of recipient seminiferous tubules and begin proliferating. Eventually, these cells establish stable colonies with a characteristic appearance, which expands and produces differentiating germ cells, including mature spermatozoa. Thus, the transplanted cells self-renew and produce progeny that differentiate into fully functional spermatozoa. In this study, to develop an alternative system of germline chimera production that operates via the testes rather than through developing embryos, the spermatogonial stem cell techniques were applied. This system consisted of isolation and in vitro-culture of chicken testicular cells, transfer of in vitro-maintained cells into heterologous testes, production of germline chimeras and confirmation of germline transmission for evaluating production of heterologous, functional spermatozoa.

Effect of dietary salmonella lysate in broiler chicks inoculated with Salmonella typhimurium on the antioxidant system(freshness) of broiler meats during 4$^{\circ}$C refrigeration was investigated. In Pectoral and leg muscle, regardless experimental diets, as the refrigeration day passed, CuZnSOD activity decreased gradually, while at 7d MnSOD activity and peroxide level raised and then lowered at 14d. MnSOD and peroxidase activity, however, had differed according to experimental diets. The results indicated that antioxidant system of broiler meats will be changed according to experimental diets(nutrients). As the CuZnSOD, MnSOD and peroxidase activity are responsible for proteolysis of muscle protein, it was concluded that change of antioxidant system during 4$^{\circ}$C storage explain the biological activity(freshness) of broiler meats.

This experiment was conducted to investigate the dietary effect of turmeric powder (TP) on laying performances, egg qualities and its transfer to eggs. A total of two hundred, 60-wk-old, Lohmann Brown layers were divided into 4 groups, placed in to 5 replicates per group (10 layers each) and fed each one of four diets containing 0 % TP(control), 0.1 % TP, 0.25 % TP, or 0.5 % TP for 7 wks, respectively. Egg production and egg mass in groups fed diets containing TP were higher than that of control(p<0.05). No differences in feed intakes, egg and eggshell qualities were observed among the treatments, but egg yolk color was increased significantly as TP was in increased in the diet(p<0.05). In groups fed diets containing TP, Haugh unit after 14 day of storage was significantly higher than that of control(p<0.05). The curcumin content of egg yolk in groups fed diet containing 0.50% TP was significantly higher than those of other groups (p<0.05). The content of egg yolk cholesterol was not influenced by dietary TP.

The effects of garlic extracts, lactic acid bacteria, copper and selenium as cholesterol lowering material on productivity and content of egg cholesterol in layer were investigated. The layers were divided into seven treatment groups and fed commercial diet or experimental diets containing probiotics, garlic powder, selenium and copper for 6 weeks. There was no significant difference in egg production between groups. The content of egg yolk cholesterol by combination feeding of probiotics, garlic powder, selenium and copper were significantly reduced by 13.5-29.8% as compared to that of control. The levels of mRNA expression of HMG-CoA reductase were significantly decreased by dietary treatments.

This experiment was conducted to study the effects of medicinal plant extract on performance in broiler chickens. A total of eight hundred forty, 1-d-old broiler chicks(Ross) were randomly allocated to 7 treatments with 4 replicates of 30 birds per replicate. The treatments were negative control (NC, diets without antibiotics), positive control (PC, diets with-containing antibiotics), Schisandrae fructus (T1), Scutellariae radix (T2), Camellia sinensis (T3), Artemisia capillaris (T4) and mixed medicinal plants (T5) extracts added to drinking water. The final body weight, body weight gain and feed conversion rate were significantly improved in all treatments compared to NC (P<0.05). No significant differences were observed in the relative weights of liver, spleen, pancreas, bursa of Fabricius and intestinal tract among the groups. The relative lengths of duodenum, jejunum and ileum were significantly decreased in PC compared with other groups (P<0.05). No significant differences were observed in the cecal microflora. The contents of triacylglycerol (TG), blood urea nitrogen (BUN), glutamic-oxaloacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) in blood serum were not significantly influenced. The concentration of cholesterol in blood serum was significantly decreased in all treated groups as compared to those of the control (P<0.05). There was no difference in the components of leukocytes and erythrocytes among the groups.

To investigate the manufacturing methods of surimi-like materials (SLM) from breast muscle of spent hen, the muscles were diced, chopped and washed with distilled water or sodium chloride solution at 0.1, 0.5 and 1% level and then washed with distilled water to extract myofibrillar protein. When used only distilled water to extract myofibrillar protein, washing was repeated 3 times followed by homogenization and centrifugation of breast muscle after each washing (CM; conventional method). Whereas, to extract myofibrillar protein using sodium chloride solution had sufficient to do 2 times washing by distilled water after 1 time washing by sodium chloride followed by homogenization and centrifugation of breast muscle after each washing (NM; new method). The both batter and cooked SLM gel from NM had significantly (p<0.05) lower redness compared with CM. Again, SDS-PAGE with sarcoplasmic protein fractions showed that the bands of phosphorylase had increased staining intensity in NM compared with CM. These results indicated that the brightness was related to sarcoplasmic protein fractions. SDS-PAGE with myofibrillar protein showed that the bands of myosin had increased staining intensity in NM compared with CM. Data implied that myofibrillar protein extraction with sodium chloride solution had the better adaptability for the breast muscle of spent hen then the commonly used distilled water method.

닭의 간은 해독작용, 당의 저장, 혈장 단백질의 합성 등 주요 기능을 하는 것으로 알려져 있다. 본 연구는 간에서 성장 단계별로 발현량에 차이를 보이는 단백질들을 비교해 보았다. 2차원적 전기 영동에 의해 분리된 300개 이상의 단백질들이 확인되었으며 이 중 성장 단계별 특이적인 13개의 단백질은 MALDI-TOF MS에 의하여 분석이 되어졌다. 본 연구를 통하여 밝혀진 단백질들은 생화학적인 연구에 중요한 자료를 제공할 것으로 사료된다.

한국재래오골계는 천연기념물로 등록이 되어 있어 세계의 중요한 유전자원 중 하나이다. 현재 한국에서 사육되어 있는 오골계의 유전적 특성을 규명하기 위하여 미토콘드리아 DNA의 변이를 이용하여 계통 분석을 실시하였다. 총 31 마리의 한국재래오골계가 이 분석에 이용되었으며 10개의 haplotypes이 관찰되었다. NJ 방법으로 만들어진 계통도 분석을 통하여 이미 닭에서 알려진 A부터 C의 lineage를 포함하는 것으로 보아 한국 재래오골계는 아직도 높은 유전적 다형성을 유지하고 있음을 알 수 있었다. 이 연구 결과는 한국 재래오골계의 육종 및 보존 계획을 세우는데 유용하게 이용될 수 있을 것으로 사료된다.

닭의 유전자 지도가 밝혀지고 그와 관련한 생물학적 연구들이 활발히 이루어지면서 닭을 생체 반응기나 질병 모델 동물로 이용하기 위한 연구가 많이 진행되고 있다. 이 중 닭을 생체 반응기로 이용하기 위해서는 많은 양의 단백질을 생산하는 난관에 대한 연구가 필수적이다. In vivo와 in vitro에서 난관 특이적 프로모터에 의한 외래 유전자의 발현에 대한 연구를 하였고 유전자를 전이하는 방법으로는 렌티 바이러스 시스템을 이용하였으며, 프로모터는 난관 특이적 프로모터인 오브알부민 프로모터 (5‘ 조절 부분의 1.4kb)와 RSV 프로모터를 이용하였다. 리포터 유전자로는 형광발현 단백질 (enhanced green fluorescence protein, EGFP)을 이용해서 마우스 배아 섬유아세포, 닭 배아 섬유아세포, 난관 상피 세포에서 발현을 유도해서 조직 특이적 발현 여부를 확인하였다. 그 결과 RSV 프로모터는 모든 세포에서 발현하였으나, 오브알부민 프로모터에 의한 리포터 유전자의 발현은 난관 상피 세포에서는 특이적으로 발현하였다. 이와 같은 연구는 산란계를 이용해서 난관으로부터 효율적인 생리 활성 물질을 생산하기 위한 가능성을 보여주었다.

생식 세포는 한 세대의 유전 정보를 다음세대에 전달할 수 있는 유일한 세포로서 다양한 특성을 가지고 있다. 기능 유전체 연구를 통해서 새로운 유전자의 기능을 규명함으로써 그 유전자의 생물학적 의미와 상호작용을 설명할 수 있다. 본 실험의 목적은 생식세포에서 특이적으로 발현하는 유전자를 발굴하여 그 유전자가 생식세포의 발달과 분화에 중요한 역할을 수행하는 것을 증명하는 것이다. 이에 본 실험에서는 real-time quantitative RT-PCR 기법을 이용하여 정소에서 특이적으로 발현하는 5개(AGE1, AGE2, AGE3, AGE4, AGE5)를 선발하였고, in situ hybridization 실험을 통하여 정소 조직 내에서의 발현 양상을 확인하였다. AGE1, AGE2는 round spermatid에서 특이적으로 발현하고, AGE3, AGE4, AGE5는 spermatocyte에서 특이적으로 발현하는 것을 확인하였다. 본 실험을 통해 발굴한 유전자들은 닭의 생식선발달에 중요한 기능을 할 것으로 예상되며, 앞으로 닭의 유전육종분야에 큰 도움을 줄 수 있을 것이다.

This study was carried out to ascertain phylogenetic status of long-tail chicken which found recently in Korea and was presumed to be a kind of Korean Natives. 10 loci microsatellites were analysed for 449 birds of 11 groups and 2 region of mitochondrial DNA were sequenced for 135 birds of the same groups, that consist of 3 introduced breeds and 8 Korean Natives including 3 long-tail chicken. In mean numbers of alleles per locus(MNA) for microsatellites, long-tail chicken were smaller (2.60${\sim}$3.20) than the others, but in heterozygosities, were higher(0.4087${\sim}$0.5375) than others that were the same level of MNA. And in the neighbor joining bootstrap tree drawing by Nei's standard distance, they made a cluster with some Korean Native groups. All of the nucleotide sequences of mitochondrial cytochrome b gene and D-loop were classified into 23 haplotypes. In long-tail chicken, the haplotypes were 3 kinds, and were different among the groups (LTA, LTB and LTD). Resultly, it was supposed that 3 groups of the long-tail chicken be all a kind of Korean Natives.

The hatchery sanitation has a significant impact on chick quality. This study was carried out to investigate the bacterial contamination in the broiler hatchery. The aerosol bacterial contamination was low except for the operating hatcher that the bacterial counts were measured almost over 300 counts/64cm$^{2}$. The bacterial contamination of the facilities and equipments had a similar tendency as compared with the aerosol bacterial contamination. More than six groups of the Salmonella species were isolated almost from the hatcher and the related facilities and equipments. Also, in this study, we compared the effects of four methods of 37% formalin adminstration in hatcher. At hatch, the aerosol bacterial counts in hatcher receiving 37% formalin as constant rate infusion method during hatching were significantly lower than in each hatcher receiving 37% formalin once at transfer and not receiving 37% formalin, respectively(p<0.05).

Fowl cholera is an infectious disease caused by .Pasteurella multocida, affecting domesticated and wild birds. It usually appears as a septicemia of sudden onset with high morbidity and mortality, but chronic conditions that characterized by localized infections often occur. 13wks broiler breeders were submitted to the Kyung-pook national university for diagnosis. Clinical signs included approximately 1% mortality, severe lameness, ruffled feathers and swollen and/or cloudy eyes. At necropsy, the outstanding lesions were seen swollen hock joint, which were suppurative or caseous exudates, inflammation of conjunctiva, severe pneumonia and epicarditis. The causative agent was isolated from the hock joint, liver, sinus and sternum of the chickens, and performed physiological and biochemical test. To identify the serotype of P. multocida, capsular serotyping was conducted by multiplex polymerase chain reaction (PCR). In the antimicrobial susceptibility test, the isolates were resistance to the aminoglycosides. In this study, we confirmed chronic fowl cholera (FC) caused by P. multocida in broiler breeders in Korea.

To reduce the economic impact and control Low pathogenic avian influenza (LPAI), vaccination with inactivated vaccine has been considered in this country. We tried to develop inactivated vaccine with reassorted H9N3 AI virus which has different type of neuraminidase compare to those of field AI virus. Before reassorted vaccine was produced, we confirm the virus as master seed by limiting dilution, RT-PCR and sequencing method. Also, we evaluate the biological characteristics of the virus to find out the possibility of prevention against field infection of AI virus. Finally, we evaluate the safety and efficacy of the vaccine made of reassorted AI virus in the specific pathogen free (SPF) chickens. After limiting dilution, we choose RV7CE4 as a vaccine candidate and compare the gene sequence of this vaccine strain to those of AI05GA which is parents strain. Compared to amino acid sequences of specific gene of AI05GA and RV7CE4, exhibited a high degree of amino acid sequence homology. In the safety and efficacy test, there were no specific clinical signs or mortality. Reassorted H9N3 viruses were reisolated in cloaca swab on 5 days post inoculation. In the vaccine study, once or twice vaccination was performed and challenged with H9N2 field virus (01310). Vaccine has no adverse effect on birds and formed good immune capability which reduce viral shedding in the birds infected with 01310. Based on the above result, we developed reassorted H9N3 vaccine which will efficiently prevent the low pathogenic AIV (H9N2) infection in the poultry farms.

This study was conducted to investigate O group serotyping, antimicrobial drug resistance and distribution of extended spectrum ${\beta}$-lactamase of 203 Escherichia coli(E. coli) isolated from poultry in Korea during the period from April in 2003 to December 2005. The serogroup of 69.4% of isolates was determinated ; O 78(32.5%), O88(7.9%). O15(6.9%) and O141(6.4%) were the most common. These E. coli isolates showed resistance to nalidixic acid(92.6%), streptomycin(81.8%), ampicillin(77.3%), ciprofloxacin(70.9%), sulfisoxazole(66.5%) and trimethoprim(58.1%), respectively. The bla CTX$_{-M-3\;like}$(2 strains) and bla$\;_{CMY-2}$(2 strains) genes producing extended spectrum ${\beta}$ - lactamase(ESBL) were detected in four wild strains resistant to the third generation cephalosporin, respectively. The presence of the ESBL genes was confirmed in all transconjugants by PCR analysis with primers encoding CTX-M-3 like types or CMY-2.