Surveillance of avian influenza virus in wild bird fecal samples from South Korea, 2003-2008.

Kang, H M,Jeong, O M,Kim, M C,Kwon, J S,Paek, M R,Choi, J G,Lee, E K,Kim, Y J,Kwon, J H,Lee, Y J [Wildlife Disease Association] 2010 JOURNAL OF WILDLIFE DISEASES Vol.46 No.3

<P>We analyzed the results from nationwide surveillance of avian influenza (AI) from birds in South Korea's major wild bird habitats and the demilitarized zone of South Korea, 2003-2008. Of 28,214 fecal samples analyzed, 225 yielded influenza viruses, for a prevalence of 0.8%. Hemagglutinin (HA) subtypes H1-H12 and all nine neuraminidase (NA) subtypes were detected. The dominant HA subtypes were H6, H1, and H4, and the most common NA subtypes were N2, N1, and N6. Among the 38 HA/NA subtype combinations, the most common were H4N6, H6N1, and H5N2. Thirty-seven low-pathogenic AI (LPAI) viruses of the H5 and H7 subtype were detected. Among them, we identified bird species for 16 H5- and H7-positive fecal samples using a DNA bar-coding system instituted in 2007; all birds were identified as Anseriformes. The HA gene of the H5 wild bird isolates belonged to the Eurasian avian lineage, and could be clearly distinguished from the sublineage H5N1 highly pathogenic AI (HPAI) of the Eurasian and American avian lineages. Whereas H7 LPAI viruses did not group as a separate sublineage with H7 HPAI viruses, H7 isolates were closely related with the Eurasian avian lineage.</P>

Supplementation of oil-based inactivated H9N2 vaccine with M2e antigen enhances resistance against heterologous H9N2 avian influenza virus infection

Park, J.K.,Lee, D.H.,Cho, C.H.,Yuk, S.S.,To, E.O.,Kwon, J.H.,Noh, J.Y.,Kim, B.Y.,Choi, S.W.,Shim, B.S.,Song, M.K.,Lee, J.B.,Park, S.Y.,Choi, I.S.,Song, C.S. Elsevier Scientific Pub. Co 2014 Veterinary microbiology Vol.169 No.3

Avian influenza virus (AIV) subtype H9N2 has been evolving rapidly and vaccine escape variants have been reported to cause circulation of infections and economic losses. In the present study, we developed and evaluated ectodomain of the AIV matrix 2 (M2e) protein as a supplementing antigen for oil-based inactivated H9N2 vaccine to increase resistance against vaccine escape variants. AIV H9N2 M2e antigen was expressed in Escherichia coli and supplemented to inactivated H9N2 oil emulsion vaccine. Specific pathogen-free chickens received a single injection of inactivated H9N2 oil emulsion vaccines with or without M2e supplementation. At three weeks post vaccination, hemagglutination inhibition tests and enzyme-linked immunosorbent assays were performed to determine serological immune responses. Challenge study using a vaccine escape H9N2 variant was performed to evaluate the efficacy of M2e supplementation. M2e antigen supplemented in oil emulsion vaccine was highly immunogenic, and a single M2e-supplemented vaccination reduced challenge virus replication and shedding more effectively than non-supplemented vaccination.

High-resolution metabolomics to identify urine biomarkers in corticosteroid-resistant asthmatic children

Park, Youngja H.,Fitzpatrick, Anne M.,Medriano, Carl Angelo,Jones, Dean P. Elsevier 2017 The Journal of allergy and clinical immunology Vol.139 No.5

<P><B>Background</B></P> <P>Corticosteroid (CS) treatment has been established as the first anti-inflammatory treatment for adults and children with asthma. However, a subset of patients fails to respond to combined systemic and inhaled CS treatment.</P> <P><B>Objective</B></P> <P>This study was aimed at further understanding CS resistance among children with severe asthma.</P> <P><B>Methods</B></P> <P>High-resolution metabolomics was performed on urine samples from CS-respondent (n = 15) and CS-nonrespondent (n = 15) children to determine possible urine biomarkers related to CS resistance. The metabolic phenotypes of CS responders and CS nonresponders were analyzed using bioinformatics including Manhattan plot with false- discovery rate, hierarchical cluster analysis, Kyoto Encyclopedia Genes and Genomes, and Mummichog pathway analysis.</P> <P><B>Results</B></P> <P>The 2-way hierarchical cluster analysis study determined 30 metabolites showing significantly different levels between CS responders and CS nonresponders. The important metabolites annotated were 3,6-dihydronicotinic acid (126.05 <I>m</I>/<I>z</I>, RT: 106, [M+H]<SUP>+</SUP>), 3-methoxy-4-hydroxyphenyl(ethylene)glycol (185.05 <I>m</I>/<I>z</I>, RT: 155, [M+H]<SUP>+</SUP>), 3,4-dihydroxy-phenylalanine (198.07 <I>m</I>/<I>z</I>, RT: 446, [M+H]<SUP>+</SUP>), γ-glutamylcysteine (236.06 <I>m</I>/<I>z</I>, RT: 528, [M+S(34)+H]<SUP>+</SUP>), Cys-Gly, (253.06 <I>m</I>/<I>z</I>, RT: 528, [M-NH<SUB>3</SUB>+H]<SUP>+</SUP>), and reduced Flavin mononucleotide (517.0794 <I>m/z</I>, RT: 533, [M+NaCl]<SUP>+</SUP>). Tyrosine metabolism, degradation of aromatic compounds, and glutathione metabolism are suggested to be significant pathways relating to CS resistance.</P> <P><B>Conclusions</B></P> <P>High-resolution metabolomics is a promising approach in asthma research. Five candidate markers were identified to be related to CS-resistant children with severe asthma. These compounds, upon validation, may contribute further in the understanding of CS resistance among children with severe asthma through the use of urine.</P>

Effect of low concentrations of hydrogen peroxide on the contractile responses of rat detrusor smooth muscle strips

Han, J.H.,Lee, M.Y.,Lee, S.Y.,Chang, I.H.,Kim, H.J.,Kim, W.,Myung, S.C. North-Holland ; Elsevier Science Ltd 2010 european journal of pharmacology Vol.638 No.1

This study was designed to determine how the contractility of rat detrusor smooth muscle strips changes in the presence of low concentrations of hydrogen peroxide (H<SUB>2</SUB><SUB>2</SUB>. The strips were dissected from the base of Sprague-Dawley rat bladders and their contractile responses to a cumulative increase in H<SUB>2</SUB><SUB>2</SUB>concentration (3x10<SUP>-6</SUP>3x10<SUP>-2</SUP>%) were measured. How the duration of exposure to the fixed concentration of 3x10<SUP>-4</SUP>% H<SUB>2</SUB><SUB>2</SUB>affected contractility was also examined. Moreover, the effect of 3x10<SUP>-4</SUP>% H<SUB>2</SUB><SUB>2</SUB>pretreatment on the response to cumulative increases in the concentrations of phenylephrine or acetylcholine (10<SUP>-8</SUP>10<SUP>-4</SUP>) was assessed. To elucidate the mechanism by which H<SUB>2</SUB><SUB>2</SUB>induced contraction, we examined the effect of pretreatment with 10nM Y-27632, 10μM indomethacin, 10μM SQ29548, 10μM verapamil, 10μM vitamin E, or 1μM Bay-K 8644 on the contractile responses generated by cumulatively increasing the concentration of H<SUB>2</SUB><SUB>2</SUB> H<SUB>2</SUB><SUB>2</SUB>induced contractile responses in Ca<SUP>2+</SUP>free physiological solution were also examined. Low concentrations of H<SUB>2</SUB><SUB>2</SUB>increased the contractile responses of the strips in a dose-dependent manner but increasing treatment duration decreased these responses. H<SUB>2</SUB><SUB>2</SUB>pretreatment significantly augmented the contraction induced by phenylephrine (P<0.05) but had no effect on the response to acetylcholine. Pretreatment with Y-27632, indomethacin, vitamin E, verapamil, and Bay-K 8644 significantly inhibited the H<SUB>2</SUB><SUB>2</SUB>induced contraction (P<0.05). SQ 29548-pretreatment had no effect. H<SUB>2</SUB><SUB>2</SUB>could not increase the contractile responses in Ca<SUP>2+</SUP>free physiological solution. Thus, low concentrations of H<SUB>2</SUB><SUB>2</SUB>may directly affect detrusor smooth muscles and thereby induce detrusor overactivity.

Supplemented vaccination with tandem repeat M2e virus-like particles enhances protection against homologous and heterologous HPAI H5 viruses in chickens

Song, B.M.,Kang, H.M.,Lee, E.K.,Jung, S.C.,Kim, M.C.,Lee, Y.N.,Kang, S.M.,Lee, Y.J. Butterworths ; Elsevier Science Ltd 2016 Vaccine Vol.34 No.5

Highly pathogenic avian influenza (HPAI) H5 viruses derived from A/Goose/Guangdong/1/96 have been continuously circulating globally, severely affecting the public health and poultry industries. The matrix 2 protein ectodomain (M2e) is considered a promising candidate for a universal cross-protective influenza vaccine that provides more effective control over HPAI H5 viruses harboring variant hemagglutinin (HA)-antigens. Here, we evaluated the protective efficacy of a tandem repeat construct of heterologous M2e presented on virus-like particles (M2e5x VLPs) either alone or as a supplement against HPAI H5 viruses in a chicken model. Chickens immunized with M2e5x VLPs alone induced M2e-specific antibodies but were not protected against HPAI H5. The homo- and cross-protective efficacy of M2e5x VLP-supplemented vaccination of chickens was also examined. Importantly, supplementation with M2e5x VLPs induced significantly higher levels of antibodies specific for M2e and different viruses as well as provided improved protection against homologous and heterologous HPAI H5 viruses. Considering the limited efficacy of inactivated vaccines, supplement vaccination with M2e5x VLPs may be an effective measure for preventing outbreaks of HPAI viruses that have the ability to constantly change their antigenic properties in poultry.

A novel chimeric promoter that is highly responsive to hypoxia and metals

Lee, J-Y,Lee, Y-S,Kim, J-M,Kim, K L,Lee, J-S,Jang, H-S,Shin, I-S,Suh, W,Jeon, E-S,Byun, J,Kim, D-K Nature Publishing Group 2006 Gene Therapy Vol.13 No.10

To develop a potent hypoxia-inducible promoter, we evaluated the usefulness of chimeric combinations of the (Egr-1)-binding site (EBS) from the Egr-1 gene, the metal-response element (MRE) from the metallothionein gene, and the hypoxia-response element (HRE) from the phosphoglycerate kinase 1 gene. In transient transfection assays, combining three copies of HRE (3 × HRE) with either EBS or MRE significantly increased hypoxia responsiveness. When a three-enhancer combination was tested, the EBS–MRE-3 × HRE (E–M–H) gave a hypoxia induction ratio of 69. The expression induced from E–M–H-pGL3 was 2.4-fold higher than that induced from H-pGL3 and even surpassed the expression from a human cytomegalovirus promoter-driven vector. The high inducibility of E–M–H was confirmed by validation studies in different cells and by expressing other cDNAs. Gel shift assays together with functional overexpression studies suggested that increased levels of hypoxia-inducible factor 1α, metal transcription factor-1 and Egr-1 may be associated with the high inducibility of the E–M–H chimeric promoter. E–M–H was also induced by hypoxia mimetics such as Co<SUP>2+</SUP> and deferoxamine (DFX) and by hydrogen peroxide. Gene expression from the E–M–H was reversible as shown by the reduced expression of the transgene upon removal of inducers such as hypoxia and DFX. In vivo evaluation of the E–M–H in ischemic muscle revealed that erythropoietin secretion and luciferase and LacZ expression were significantly higher in the E–M–H group than in a control or H group. With its high induction capacity and versatile means of modulation, this novel chimeric promoter should find wide application in the treatment of ischemic diseases and cancer.Gene Therapy (2006) 13, 857–868. doi:10.1038/sj.gt.3302728; published online 9 February 2006

공정육모 온실의 표준모델 및 자동화 시스템 개발과 활용기술연구 1 : 제1장 서론 Chapter1 Introduction

박중춘,민영봉,정병룡,설인준,이영만,윤용철,강호종,김태규,김광용,장사문,정한택,오태한,김평태,김진일,손영걸,박봉식,김시론,이형정,오상석,김명승,조정호,하종규,임동희,이은주,변정희,이정한,최우진,강환규 경상대학교 시설원예연구소 1997 施設園藝硏究 Vol.4 No.-

Ⅰ. 제목 공정육묘온실의 표준모델 및 자동화 시스템개발과 활용기술연구 Ⅱ. 연구개발의 목적과 중요성 1. 목적 1) 농가보급형 공정육모 표준온실의 설계 2) 공저육모온실의 시설장비의 표준화 3) 공정묘 생산을 위한 시설장비 자동화 시스템 개발 2. 중요성 1) 공정묘 생산을 위한 표준온실 및 자동화시스템의 연구개발은 원예묘의 분업화, 전문화 생력화를 위하여 필요하다. 우리나라 채소류 총소요량은 1996년말 현재 약 140억본으로 추산된다. 이를 위한 공정육모장의 표준시설 설계도가 없을뿐 아니라 재배생산 기술 및 경영체계가 또한 확립되어 있지 않다. 2) 농림부에서는 채소 공정육모장 설치를 위한 자금을 농가에 지원하고 있다. 그러나 적정시설의 규모, 시설설비를 위한 자금의 범위등이 확립되어 있지 않을 뿐아니라 수용농가는 육묘장 관리 및 재배기술이 미흡하며 경영계획 및 경영분석 모델이 확립되어 있지 않아 생산현장에서 많은 애로를 느끼고 있는 실정이다. Ⅲ. 연구개발과 내용 및 범위 1. 공정육묘를 위한 온실 표준화 연구 가. 공정육묘시스템 도입을 위한 검토 나. 공정육모온실의 표준모델 설정 다. 공정육모온실의 시설장비 및 자재 규격화 라. 공정묘 보급과 생산량 예측 및 묘의 표준규격 2. 공정육묘의 자동화 시스템 개발 가. 자동파종시스템 개발 나. 묘 이송라인 개발 다. 발아실 표준규격 정립 라. 온실의 재배관리 장치개발 마. 복합환경제어 장치개발 3. 공정묘 생산기술 개발 가. 공정묘 생산과 보급을 위한 나. 공정묘용 상토 및 액비개발 시험 다. 공정묘에서 양액의 농도와 DIF가 생육에 미치는 영향, 그리고 작부체계 계획 라. 플러그 잡목묘 재배생산시험 마. 공정묘 육성에 식물활성물질 이용효과 시험 바. 고추 공정묘의 생장조절시험 사. 공정육묘의 육묘농가 적응시험 4. 공정육모사업의 경영분석과 경영체계 수립 가. 공정육묘사업의 경제성 분석 나. 공정육묘농장의 경영체계 수립의 실제 Ⅳ. 연구개발 결과 및 활용에 대한 건의 1. 연구개발 결과 공정육묘온실의 표준모델 및 자동화시스템 개발과 농가활용 기술에 관한 연구를 위하여 우리나라 농가에 보급할 수 있는 표준온실설계, 온실내 도입되어야할 시설장비의 자동화시스템 개발과 이들의 표준화 연구, 공정묘 생산을 위한 다각적인 재배기술 시험, 그리고 표준온실에 대한 육묘농가의 경영분석 표준모델 등에 대한 조사분석, 설계, 시험 등을 실시하였든바 그 결과를 요약하면 다음과 같다. 가. 공정육묘를 위한 온실 표준화 연구 1) 우리나라 원예작물의 묘생산을 공정화 하기 위하여 검토되어야할 플러그묘의 특징, 선진외국 플러그묘의 생산기술 현황, 플러그묘의 이용효과, 우리나라의 육묘현황과 문제점 등을 고찰하였고 또한 육묘의 작업공정별 주요내용을 검토하여 플러그육모 시스템 도입을 위한 문제점을 제시하였다. 이를 표준모델 설정의 기본자료로 삼았다. 2) 공정육묘용 표준온실을 설계하기 위하여 온실구조, 장치, 자재 등에 대한 종류별 특성과 도입규모를 정리하였다. 3) 온실의 설게는 양지붕형 철골유리온실(3G)과 지붕형 경질피복재온실(2P형) 등 2가지 형태로 표준화 하였으며 유리온실은 면적 4,914㎡(1,500평형), 경질재온실은 면적 3,304㎡(1,000평형)으로 각각 설계하였다. 그리고 이들 2형태의 온실을 각각 독립형과 2동 분리형(3G-S형, 2P-S형)으로 설계하였으며 분리형은 여러작물을 동시에 육묘하고자 할 때 환경조절을 용이하게 제어할 수 있도록 하였다. 온실설계에 포함한 내용은 설계도, 1회 최대 묘생산량 예측, 공사비 내역, 시방서, 눈과 바람에 대한 구조안정성 해석등 이며 각 형태별 표준온실도서는 본 연구 보고서의 별책 부록으로 작성하였다. 4) 공정육묘온실의 효율적 안전관리를 위한 작업공정 내용을 자재의 준비부터 묘출하에 이르기까지 17개항에 대하여 세부사항을 기술하였다. 나. 공정육묘온실의 시설장비 및 자재 규격화 1) 육묘온실의 베트, 보온용 커튼개폐장치, 자주식 두상관비장치, 액비혼입기, 무인방제기, 복합환경제어장치, 발아실, 접목활착초진장치, 자동파종시스템 등 공정육묘온실에 도입되어야 할 시설장비에 대한 용도와 성능을 검토하였다. 2) 공정묘 생산에 필수자재인 트레이, 상토 등에 대한 규격, 특성, 묘생산과 관련된 사항 등을 검토하였다. 3) 공정묘의 보급과 관련된 문제점을 관행묘와 비교하여 검토하였으며 양질의 공정묘가 갖추어야할 구비조건을 제시하였다. 4) 우리나라 공정묘의 수요전망과 생산량을 예측하였고 공정묘 보급율 30% 기준에서 2004년까지 적어도 1,500평 규모의 시설이 180여개가 도입외어야 할 것으로 추산되었다. 5) 주요 작물별 공종묘 출하규격과 유통가격을 조사분석 하였으며 이를 트레이 규격별로 산출하여 설계된 표준온실의 경영분석 자료로 활용하였다. 다. 공정육묘이 자동화 시스템 개발 1) 자동파종시스템 개발 자동파종 시스템은 상토의 혼합, 트레이의 공급, 상토의 충전, 진압, 파종, 복토, 관수, 발아실 이송 등의 단계를 자동으로 전체작업이 이루어지도록 하였다. 작업공정은 2인의 작업자가 200공 트레이 150매/시간 의 작업능률를 가질 수 있도록 구성하였다. 자동파종기는 트럼형과 노즐형 2가지 형태로 설계, 제작, 시험하였다. 노즐형파종기의 작업속도는 180트레이/시간 으로 드럼형의 300트레이.시간 보다 늦었다. 반면에 파종효율은 노즐형이 98%로서 드럼형의 90%보다 높고, 또한 종자의 형상과 크기에 관계없이 노즐형이 효과적인 파종이 가능하였다. 따라서 상품화를 위한 파종기는 노즐형으로 하였다. 2) 온실의 묘이송라인 개발 육묘용 베드는 수동좌우이동형으로 하였으며 폭은 1,900mm로 하였고 길이는 40m 이내로하여 온식폭 9m에 4열로 배치하였다. 그리고 베드위에 표준규격 트레이 540x270mm를 길이 방향으로 7열로 배열할 수 있게 하였다. 이때 온실면적에 대한 육묘면적비는 76-79%범위에 있었다. 접목활착실의베드는 고정형으로 하였으며 베드폭은 1,800mm로 하였고 온식폭 9m내에 3열로 배치하였다. 그리고 베드상에 표준트레이 6매를 길이방향으로 배열할 수 있게 하였다. 이때 온실면적에 대한 접목묘면적비는 55-56%범위에 있었다. 트레이 이송방식은 육묘베드상에서 베드자체를 이동하는 방식과 트레이 탑차를 이용하는 방식등 2종류의 시제품을 개발하였다. 그러나 베드이송방식은 생력화면에서 탑차방식보다 5배의 능율이 있었으나 제작비가 약 10배이상 높게 요구될 뿐아니라 아직 베드이 이동라인 활용도가 미흡할 것으로 판단되어 표준온실에는 트레이 탑차방식을 도입하였다. 3) 발아실의 표준규격 정립 발아실은 보온단열성이 높은 200mm 스티로폴 압착판넬을 벽체에 이용하였고 단위면적당 냉난방부하는 36kcal/hr·㎡로 하고, 냉난방용량은 166. 4 kcal/㎡·hr으로 산출되었다. 가열방식은 지면온수난방으로서 방열관은 엑셀파이프(25Ψ)를 15㎝ 간격으로 배열할 때 충분하였다. 가습장치는 냉방시 최대 제습량 0.8g/㎡·min을 고려하여 설계되었으며 이때 가습기의 분무입자 15㎛, 용량은 g/㎡·min에서 10분이내 95% RH 균일가습이 가능하였다. 4) 온실의 재배관리장치 개발 공정육묘온실에 필요한 시설장비는 매우 많다. 본 연구에서 기존의 것들을 개선하기 위하여 시제품을 만들어 개발한 것은 자주식 두상관비장치, 양액혼입장치, 냉방장치, 초미립자 무인방제장치, 온실차단 분리용 수직커튼개폐장치의 응용 등이다. 5) 복합환경제어장치 개발 본 연구에서는 하드웨어와 소프트웨어 개발을 구분하였고, 하드웨어 개발에서는 각 센서의 정밀성, 인터페이스카드와 전용 컨트롤러의 안전성, 현장제어반의 전기배선 최적회로, 서지와 잡음 및 전자파 충격방지 기술개발이 수행되었다. 소프트웨어 개발에서는 농가현장에서 편리하게 사용할 수 있는 메뉴 및 조작 프로그램제작에 주안점을 두었으며 환경설정치의 제어은 P,PID,Fuzzy기법을 도입하였다. 계측항목으로는 온도, 습도, 공기순환, 관수, CO_2공급, 보온, 수막, 이상기후, 양액공급, 정보등이다. 본 장치는 농가에 설치하여 적응시험을 설시하고 평가를 받아본봐 95%이상의 만족도를 보였다. 라. 공종묘 생산기술개발 1) 공정묘 생간과 보급을 위한 육묘관리 및 재배기술 공정묘의 안정적 생산과 묘수용농가 확대를 위한 능율적 보급을 위하여 몇가지 육묘 재배기술에 대한 자료를 정리 고찰하였다. 공정육묘의 생육단계별 환경관리, 상토의 관리, 관수와 시비기술, 적정용수와 양액의 조제, CO_2시비효과, 공정묘의 생육조절과 관련된 몇가지 재배기술, 접목묘의 생산, 다년생식품의 춘화처리 공정묘 특성, 고온기의 온실 냉방방법의 종류, 병해충 관리, 묘생산후의 관리, 공정묘의 정식후 관리 등 여러분야의 내용을 요약하였다. 2) 공정육묘용 상토 및 액비개발 시험 공정육묘용 상토선발 및 액비시용효과 시험을 실시하였다. 개발된 상토는 「토실이」로, 액비는 「양실이」로 각각 명명되어 상품화 하였으며 이들 재료로 주요작물에 대한 적응시험이 수행되었다. 시험내용은 고추, 토마토, 배추 등은 대상으로 국내외 시판상토 비교시험, 상토재원중 피트모스대용 코이어 도입시험, 기비성상토 개발시험 등이 수행되었다. 3) 공정묘에서 양액의 농도와 DIF가 생육에 미치는 영향, 그리고 작부체계 계획공정묘 생산에 있어서 양액의 질소농도와 NH_4:NO_3 비율 및 최초시용시기가 생육에 미치는 영향에 대하여 수박접목묘와 고추묘를 대상으로 시험하였다. 수박접목묘에서는 전반적인 생육과 묘소실면에서 질소농도가 16meq·ℓ^-1, NH_4:NO_3 농도비에서 15:85%인 처리구가 우수하였고 접목이전 양액시용의 효과는 업었다. 고추묘 생육에서는 총이온농도가 25 meq·ℓ^-1 그리고 NH_4:NO_3 비율이 30:70% 정도로 재배하는 것이 적당할 것으로 사료되었다. 주야간 온도차(DIF)가 고추 및 토마토 플러그묘의 생육에 미치는 효과시험에서 +DIF, 0DIF, 변온 DIF를 각각 처리한 바 고추의 경우 조사형질에 따라 다소 차이는 있었으나 초장에서는 처리간에 비슷한 경향을 보였다. 그리고 토마토에서는 고추보다 유의차가 있는 형질의 많았고 특히 초장에서 0 DIF가 가장 짧고, 변은 DIF에서 가장 길며 1%의 유의성을 보였다. 공정묘의 연중생산을 위한 작부체계 모형검토와 작부체계별 생산계획을 위하여 우리나라 주요 공정묘인 고추, 수박, 오이, 토마토를 대상으로 현재조사 결과를 바탕으로 수요창출을 위한 작형을 검토하였다. 4) 플러그 접목묘 재배생산시험 과채료 접목묘 생산을 위한 종합적 검토가 이루어졌다. 즉 접목방법의 이론적 배경과 접목부의 조직학적 관찰, 수박, 오이, 토마토, 가지 등의 접목방법과 접목후 관리방법, 접목친화성, 위조현상, 자근발생, 대목의 부패, 왜화현상 등의 접목묘 생산에 대한 문제점 검토, 접목표의 활착부위정도가 묘생육과 정식후의생육과 수량에 미치는 영향 등에 대한 시험이 수행되었다. 그리고 수박, 오이 등의 작물을 공시하여 핀접목, 꽂이접, 유근접, 단근접 등 접목별로 농가적응시험을 실시하였고, 또한 본 과제에서 개발한 접목할착촉진장치의 이용효과에 대한 시험을 실시하였다. 5) 공정묘 육성에 식물활성물질 이용 효과시험 건전공정묘 육성을 위하여 몇가지 식물활성물질의 처리효과 시험이 수행되었다. 처리된 활성 물질은 Chitornate G, Aika, Hi-Atonic, Menedaeael등이었고 공시작물은 고추, 수박, 토마토, 미니토마토, 배추, 장미 등이었으며 시험내용은 종자침지효과, 묘생육시험, 접목묘생산시험, 공정묘의 노지정식 적응시험, 장미삼목시 발근효과 시험 등이 수행되었다. 6) 고추공정묘의 생산조절기술 플러그묘의 생장조절 필요성을 검토하였으며 또한 몇가지 생장조절기술에 대한 시험과 정식후에 미치는 영향 등에 대하여 실험하였다. 즉 생상조절의 이용, DIF처리에 의한 효과, 그리고 시비량조절에 의한 생장조절 등이었다. 특히 시비량조절에 의한 생장조절 시험에서는 생육단계별로 인산농도를 조절하거나 단비하므로서 초장뿐아니라 생장이 억제되었다. 그리고 인산시비조절에 의한 생장억제묘가 정식후 생육과 수량에 좋은 영향을 미쳤다. 이러한 결과는 경제적이고 가장 안정한 조절방법으로서 금후 고추뿐만아니라 여타작물에 대한 시험이 필요하였다. 7) 공정육묘 생산을 위한 육묘농가 현장 적응시험 공시작물은 토마토와 고추로 하였으며 시험내용은 공정묘의 육묘일수, 관행육묘와 공정육묘의 비교, 두상관수와 저면관수의 비교, 그리고 육묘배지 종류별 양액종류 및 양액농도 비교시험 등을 수행하여 적절한 조건을 규명코져 하였다. 또한 공정묘의 효율적인 보급를 위해 재배농가 실증시험을 실시하여 정식후 초기생육정도를 조사분석하였다. 마. 공정육묘사업의 경영분석과 경영체계 수립 1) 공정육모사업의 경제성 분석 공정육모의 경제성 분석은 본 과제에서 설계된 3G형 유리온실과 2P형 경질재 온실의 2가지 설계도서와 자재비 명세내용을 근거로 분석되었다. 3G형 유리온실은 1,500평 규모에서 평당 914천원이 투자되었고 2P형 경질재온실은 1,000평 규모에서 평당 851천원이 투자되어 투자비용 측면에서는 경질재온실이 상대적으로 낮았다. 공정육모 표준온실의 경영성과 분석에서 순수익율은 약 40-50%수준이었고, 총자본 수익율은 작물의 재배체계의 따라 33-49% 범위에 있어 현재의 경제조건에서는 투자경제성이 있는 것으로 판단되었다. 2) 공정육모농장의 경영체계 수립의 실제 기업형 육묘농장의 합리적 운영을 위하여 계획의 수립에서부터 경영일지 작성까지 제문제에 대하여 분야별 기록장을 예시하였다. 예를들면 육묘면적의 배치계획도 작성, 묘의 출하가격과 출하량예측, 예상되는 수입금 계획과 수지계획, 그리고 종자비, 비료비, 농약비, 상토 및 틀이 구입비, 감가상각비, 묘츌하비용, 노용임금 등에 대한 지출비 계획과 육묘 관리를 위한 작업계획등을 체계적으로 기록작성할 수 있도록 하였으며 이를 기초로 경영 분석과 평가가 이루어질 수 있게 하였다. 2. 활용에 대한 건의 가. 활용계획 1) 농림부-공동육묘장 시설생산유통 지원사업의 기준으로 활용 2) 산업체-온실, 시설장비, 자동화시스템 등의 국산화 개발 - 트레이, 상토, 액비 등 묘생산 자재의 표준화 및 국산화 개발 3 농업인-시설의 도입규모, 육묘장의 운영관리등 생산체계정립에 활용 -공정묘 생산을 위한 필요자재의 선택, 재배생산기술의 향상, 묘 주년 안전생산 정립 4) 학계-화훼류, 목본류의 공정육묘, 시스템 개발을 위한 선행연구 -식물공장형 생산시스템 개발의 기초자료 나. 활용자료 1) 농가보급형 공정육묘 표준온실의 설계도서(보고서 부록) 2) 발표된 논문 (1) 손영걸, 박봉식, 김시론, 임동희, 박중춘. 1996. 고추프러그 육묘에 있어서 상토혼잡 비율이 생육에 미치는 효과. 한국원예학회 발표요지 14(2):250-251. (2) 손영걸, 박봉식, 김시론, 임동희, 박중춘. 1996. 수박 핀 접목에서 접수령과 절단경사별 처리가 가습 활착실 차이에 따른 효과. 한국원예학회 발표요지 14(2):266-267. (3) 정병룡, 손영걸, 박언정, 김진일, 박중츤. 1996. 공정육묘용 상토선발시험, 경상대 시설원예연구보고 1:1-5. (4) 정병룡, 손영걸, 박언정, 이형정, 김진일, 박중춘, 1996. 공정육묘용 상토선발과물거름 시용 효과 시험. 경상대 시설원예연구보고 1:6-13. (5) 손영걸, 박봉식, 임동희, 김시론, 김진일, 박중춘. 1996. 토실이 상토와 국내외 몇가지 상토의 고추 육묘 비교시험, 경상대 시설원예연구보고 1:14-19. (6) 손영걸, 박봉식, 임동희, 김시론, 김진일, 박중춘. 1996. 토실이 상토와 국내외 몇가지 상토의 배추 육묘 비교시험. 경상대 시설원예연구보고 1:20-25. (7) 손영걸, 박봉식, 김시론, 임동희, 김진일, 박중춘. 1996. 토실이 상토의 코이어 도입 시험. 경상대 시설원예연구보고 1:26-32. (8) 박봉식, 이형정, 김시론, 오상석, 손영걸, 박중춘. 1996. 프러그 육묘종 상토의 코이어 혼합비율과 물거름에 목초산 혼합여부가 고추육묘에 미치는 효과 상호비교 시험. 경사대 시설원예연구보고 1:33-41. (9) 손영걸, 박봉식, 박언정, 김시론, 임동희, 이형정, 오상석, 박중춘. 1996. 프러그육묘용 상토의 코이어 혼합비율과 물거름에 목초산 혼합여부가 수박접목 육묘에 미치는 효과 상호비교 시험. 경상대 시설원예연구보고 1:42-48 (10) 손영걸, 박봉식, 박언정, 김시론, 임동희, 이형정, 오상석, 박중춘. 1996. 프러그 육묘용 상토이 코이어 혼합비율과 물거름에 목초산 혼합여부가 배추육묘에 미치는 효과 상호비교 시험. 경상대 시설원예연구보고 1:49-55. (11) 손영걸, 박봉식, 김시론, 임동희, 박중춘 1996. 수박핀 접목에서 접수령과 절단 경사별 활착비교와 가습활착실 이용 효과 분석. 경상대 시설원예연구 용역보고 1:56-64. (12) 박중춘. 1997. 원예용 상토의 개발 방향과 토실이의 특성. 신안그로 창사기념심포지움. 워크샵. 신안그로 1-26. (13) 손영걸. 박봉식, 오상석. 김시론, 박중춘. 1997. 수박 단근핀 접목에서 작물활력소 Menedael의 처리효과 시험(Ⅰ). 경상대 시설원예연구소 연구보고. pp. 7. (14) 손영걸, 박봉식, 오상석, 김시론, 박중춘. 1997. 수박 단근핀 접목에서 작물활력소 Menendael의 처리효과 시험(Ⅱ). 경상대 시설원예연구소 연구보고. pp.7. (15) 박중춘, 민영봉, 장점수, 정영경, 1997. 한국형 공정육묘장의 표준 시설장비와 플러그묘의 생산. 용현농협육묘장 완공세미나 자료집. 1-34. (16) 민영봉, 박중춘, 정한택, 오태한, 이상옥. 1997. 공정육묘장의 자동화를 위한 신개발 시설장비. 용현농협육묘장 완공세미나 자료집. 35-76. (17) 박중춘, 정병룡, 손영걸, 정한택, 장전수. 1997. 육묘용상토 「토실이」와 물거름 「양실이」개발 및 육묘효과 시험. 용현농협육묘장 완공세미나 자료집. 93-146. (18) 이영만, 박중춘. 1997. 공정육묘온실의 경영계획과 분석 프로그램. 용현농협육묘장의 경영시산분석. 용현농협육묘장 완공세미나 자료집. 147-166. (19) 강호종, 구우서, 박중춘. 1997. 접목정도가 수박묘 소질 및 수량에 미치는 효과. 한국원예협회 영남지부 가을 논문발표 요약집. p.16. 3) 출원 또는 등록된 산업재산권 ◁표 삽입▷(원문을 참조하세요) For the development and application of standard greenhouse models and of automated systems of plug seedling production, research on the design of standard greenhouses to be introduced in Korea, on development and standardization of facility, equipment and materials of the plug production greenhouses, on plug seedling production techniques, and on management analysis of plug producers was conducted and the results are summarized as follows. 1. Research on the Greenhouse Standardization for the Plug Production Systems 1) Things necessary for mechanization of the plug production system, such as characteristics of the plug seedlings, status and technology of plug production in the developed countries, effects of utilizing plug seedlings, and current status of technology and problems of plug production in Korea, were discussed. In addition, based on the evaluation of major factors involved in each step of seedling culture, problems related to the introduction of plug production systems were suggested. And this information was used as base data for the establishment of the standard models. 2) To design standard greenhouses for plug production, characteristics and introduction sizes of greenhouse structure, facility and materials were systemized. 3) Two greenhouse models, and even-span steel frame glass house (3G) and an even-span greenhouse with rigid covers (2P), with 4,914㎡ (1,500 pyung) and 3, 304㎡ (1,000 pyung), respectively, were chosen as standard models. Both models were designed to be constructed either as one gutter-connected greenhouse or as two separate gutter-connected greenhouses (3G-S and 2P-S, respectively). The latter one was designed for the ease of environment control necessary for raising seedlings of different crops at the same time. The drawings of standard greenhouse designs were attached as a separate book. Greenhouse design, estimates of maximum number of seedlings which can be produced as a time, construction costs, specifications of the construction, and analysis of structure safety against snow and wind loads were included. 4) Seventeen stepwise work processes from materials preparation to seedling marketing were described for an efficient safety management of the greenhouses. 2. Standardization of Facility, Equipment and Materials for the Plug Production 1) Usage and function of the equipment and facility, such as beds, and opening and closing system of thermal curtains, a travelling overhead fertigation system, a fertilizer injector, and automated chemical fogger, an integrated environment control system, a germination chamber, a graft union promoting system, and an automatic seeder, were discussed. 2) Size, characteristics, and other factors related to seedling production, such as trays and germination media which are absolute necessity in plug production, were investigated. 3) Problems related to plug utilization were investigated against the traditional seedlings, and requirements of the high quality plug seedlings were suggested. 4) Estimates on the demand and production capacity of plug seedlings in Korea were predicted. Based on 30% of the total seedlings consumed nationwide are replaced with plug seedlings, it seems that at least 180 of 1,500 pyung plug production greenhouses will be needed by the year 2004. 5) Sizes and prices of the major plug seedling crops were investigated and analyzed, and were used for the analysis of management analysis of the plug greenhouses. 3. Development of Automated Systems 1) Development of automated seeding systems The automated seeding systems developed are automatically capable step by step of medium mixing, tray supplying, medium filling and packing, sowing, covering, irrigation and moving to the germination chamber. The work process needs two persons and has the capacity of 150 200-cell trays per hour. Automated seeders of drum and nozzle types were designed, developed and tested. The capacity of the nozzle seeder is slower with 180 trays per hour compared to the drum seeder which can handle up to 300 trays per hour. However, the nozzle seeder has 98% sowing efficiency, compared to 90% of the drum seeder, and is more effective in terms of handling seeds of irregular shapes and sizes. Therefore, only the nozzle seeder was commercialized. 2) Development of seedling moving lines in the greenhouse The greenhouse beds were built manually movable sideway and were manufactured in sizes of 1,900㎜ wide and less than 40m long so that 4 bed lines fit in each 9m wide greenhouse. On top of each bed 7 rows of standard 540㎜×270㎜ trays fit longitudinally. This arrangement gives effective culture area of 76-79%. The 1,800㎜ wide beds in the graft union promotion tunnels were fixed so that 3 rows fit in 9m greenhouses. On top of each bed 6 rows of standard trays fit longitudinally and this arrangement gives effective culture area of 55-56%. Two tray moving systems, movable beds on top of bed rails, and movable tray racks were developed. Movable beds had 5 times higher efficiency than the tray racks. However, since movable beds costs 10 times more than the tray racks to manufacture and since the bed moving on rails is assumed not commonly used, only the tray racks were introduced. 3) Establishment of standard specifications of the germination chamber 200㎜ thick pressed styrofoam panels which have a high thermal insulation efficiency were used on the walls. The germination chamber was estimated to need a cooling load of 36 ㎉·h^-1·㎡, and cooling and heating capacity of 166. 4 ㎉·h^-1·㎡. Floor heating with 25㎜ XL pipes arranged at a 15㎝ interval as radiators gave sufficient heat. Fogging system was designed considering the maximum removal of 0.8g·min^-1·㎡ of water during cooling. With fog particle size of 15㎛ and with fogging capacity of 5g·min^-1·㎡, 95% relative humidity was achieved in 10 minutes. 4) Development of a greenhouse culture management system There are many facility and equipment which the plug production greenhouses need. Among the facility and equipment which have been improved by making prototype models in this research are a travelling fertigation system, a fertilizer injector, a cooling system, an ultrafine fogger system, and an application of vertical curtain for the separation of greenhouse area into sections. 5) Development of an integrated environment control system Hardwares and softwares were developed. Hardwares with an emphasis on the precision of different sensors, safety of the interface cards and controllers, optimization of the circuit composition of the local control panel, and prevention of surge, noise and shock were developed. Software development was focused on grower-friendly menus and control programs. For the control of environment set points, P, PID and fuzzy technology were introduced. Factors such as temperature, humidity, air circulation, CO^2 supply, insulation, water curtain, abnormal climate, and fertilizer supply are controlled. The grower responses to the field trials showed satisfaction over 95%. 4. Development of Plug Seedling Production Techniques 1) Management and cultural techniques for the production and utilization of plug seedlings For-stable production and popularization of plug seedlings, materials on the plug seedling culture and techniques are collected and analyzed. Information on such cultural management and techniques are summarized as environment control at different stages of seedling growth, medium management, irrigation and fertilization technique, water quality and preparation of nutrient solutions, CO^2 fertilization, control of growth, production of grafted seedlings, vernalization of perennial plug seedlings, and postharvest handling of the plug seedlings. 2) Study on the development of growing media and nutrient solutions Growth of seedlings of major greenhouse crops on different growing media and with different nutrient solutions were evaluated. The medium and nutrient solution developed and commercialized were named “Tosilee” and “Yangsilee”, respectively. Comparison experiments with pepper, tomato and chinese cabbage of different media formulated in Korea as well as in other countries, replacement of peat moss in the media with coir, and inclusion of nutrition in the media were conducted. 3) Effect of nutrient levels, NH_4:NO_3 ratio, and DIF on the growth of plug seedlings, and analysis of cropping systems A study was conducted to examine the effect of N concentration and NH_4:NO_3 ratio of the nutrient solution, and time of first fertigation on the growth of plug seedling of grafted watermelon. Watermelon shoots grafted to gourd rootstock were planted in 50-cell plug trays and were fertilized with one of the nine nutrient solutions starting from either one day prior to or five days after grafting. Nutrient solutions contained either 8.0, 16.0 or 24.0 meq·ℓ^-1 N which consists of either 1:100, 15:85 or 30:70 in % NH_4:NO_3 ratio. Overall grafted seedlings with best growth and quality were produced in treatment with 16 meq·ℓ^1 N with a NH_4:NO_3 ratio of 15%:85%. However, feeding of the seedlings prior to grafting was not beneficial. The second study investigated the growth of pepper plug seedlings as affected by total ion concentration and NH_4:NO_3 ratio of the nutrient solution. Pepper seedlings grew the best with 25 meq·ℓ^-1 total ion concentration and 30%:70% NH_4:NO_3 ratio. In the third experiment, the effect of KIF on the stem elongation of pepper and tomato plug seedlings was studied. The three temperature treatments used were +DIF, 0DIF and alternating temperatures. The results showed that 0DIF was the most effective and alternating temperatures the least effective in suppressing stem elongation in both species. Other growth parameters were also affected by the treatment. In addition, the current cropping systems of plug production greenhouses for pepper, watermelon, cucumber and tomato were investigated, and based on those possible future cropping systems desirable for the creation of demand on plug seedlings were suggested. 4) Study on the culture of grafted plug seedlings Integrated discussion on the grafted seedling production of fruit vegetables was included. In other word, theoretical basis of grafting methods, anatomical observations of the graft unions, grafting methods and care after grafting of the watermelon, cucumber, tomato and eggplant seedlings, and problems related to graft compatibility, wilting, scion rooting, rotting of root stocks and dwarfing, and effect of graft union on growth of the plants and yield were investigated. In addition, pin grafting, radicle grafting, and cutting graft were applied and tested to watermelon and cucumber in commercial plug production greenhouses. And the graft union promoting chamber developed in this study was tested for its efficiency. 5) Study on the Effect of Growth Activating Materials on Plug Seedling Growth In n effort to produce quality plug seedlings, several materials were tested for their effect as growth activators. Seeds of pepper, watermelon, tomato, cherry tomato, and chinese cabbage, and cuttings of rose were soaked in solutions of Chitomate G, Aika, Hi-Atonic, and Menedael, and effect of these materials on plug seedling growth, grafted seedling growth, seedling transplanting, and rooting was examined. 6) Study on the Growth Regulation of Pepper Plug Seedling The need for growth control of the plug seedlings was discussed and several growth control methods were evaluated for their effectiveness and effect on plant growth and development after transplanting, These include use of growth regulators, use of DIF, and use of controlled fertilization. In the controlled fertilization experiment, control of phosphate at different stage of seedling growth or no fertilization gave suppressed height and growth. However, the growth suppressed-seedlings gave increased growth the yield after transplanting. This method seems to be very economical and safe and needs to be tested for other species. 7) Field Trial Experiments in the Commercial Greenhouses on the Plug Seedlings Production The experiment compared growth of plug seedling of pepper and tomato as affected by seedling age, traditional seedlings vs plug seedlings, overhead vs flood irrigation, growing medium, and type and total ion concentration of the nutrient solution. In addition, in an effort to promote plug seedling utilization early stage growth of theses species after transplanting to commercial greenhouses was evaluated. 5. Management Analysis of Plug Production Business and Establishment of Management System 1) Economic Analysis of the Plug Production Business Economic analysis of the plug production business was made based on the construction design and material specifications necessary for the two greenhouse types, 3G glass house and 2P rigid cover greenhouse. A 1,500 pyung 3G glass house needs capital investment of 914,000 won per pyung and a 1,000 pyung 2P rigid cover greenhouse 851,000 won per pyung, which is lower that the 3G glass house. Analysis of management effect of the standard greenhouses showed net return rate of 40-50%, and total capital return rate of 33-49%, depending on the cropping system. Therefore, under current economic conditions, it is thought that plug greenhouses are worthy of economic investment. 2) Practical Establishment of Management System of the Plug Production For sound management of enterprise-type plug greenhouses, recording booklet for different parts from establishment of plan to writing of a management diary was exemplified. For example, drawing of culture area arrangement, prediction of seedling prices and demand, predicted income and balance, expenses for seeds, fertilizers, chemicals, trays, growing medium, facility depreciation, marketing and labor, and work plan for seedling culture can be systematically recorded and the management effect can be evaluated based on theses factors.

Selection for Duration of Fertility and Mule Duck White Plumage Colour in a Synthetic Strain of Ducks (Anas platyrhynchos)

H.C. Liu,J.F. Huang,S.R. Lee,H.L. Liu,C.H. Hsieh,C.W. Huang,M.C. Huang,C. Tai,J.P. Poivey,R. Rouvier,Y.S. Cheng 아세아·태평양축산학회 2015 Animal Bioscience Vol.28 No.5

A synthetic strain of ducks (Anas platyrhynchos) was developed by introducing genes for long duration of fertility to be used as mother of mule ducklings and a seven-generation selection experiment was conducted to increase the number of fertile eggs after a single artificial insemination (AI) with pooled Muscovy semen. Reciprocal crossbreeding between Brown Tsaiya LRI-2 (with long duration of fertility) and Pekin L-201 (with white plumage mule ducklings) ducks produced the G0. Then G1 were intercrossed to produce G2 and so on for the following generations. Each female duck was inseminated 3 times, at 26, 29, and 32 weeks of age. The eggs were collected for 14 days from day 2 after AI. Individual data regarding the number of incubated eggs (Ie), the number of fertile eggs at candling at day 7 of incubation (F), the total number of dead embryos (M), the maximum duration of fertility (Dm) and the number of hatched mule ducklings (H) with plumage colour were recorded. The selection criterion was the breeding values of the best linear unbiased prediction animal model for F. The results show high percentage of exhibited heterosis in G2 for traits to improve (19.1% for F and 12.9% for H); F with a value of 5.92 (vs 3.74 in the Pekin L-201) was improved in the G2. Heritabilities were found to be low for Ie (h2 = 0.07±0.03) and M (h2 = 0.07±0.01), moderately low for Dm (h2 = 0.13±0.02), of medium values for H (h2 = 0.20±0.03) and F (h2 = 0.23±0.03). High and favourable genetic correlations existed between F and Dm (rg = 0.93), between F and H (rg = 0.97) and between Dm and H (rg = 0.90). The selection experiment showed a positive trend for phenotypic values of F (6.38 fertile eggs in G10 of synthetic strain vs 5.59 eggs in G4, and 3.74 eggs in Pekin L-201), with correlated response for increasing H (5.73 ducklings in G10 vs 4.86 in G4, and 3.09 ducklings in Pekin L-201) and maximum duration of the fertile period without increasing the embryo mortality rate. The average predicted genetic response for F was 40% of genetic standard deviation per generation of selection. The mule ducklings’ feather colour also was improved. It was concluded that this study provided results for a better understanding of the genetics of the duration of fertility traits in the common female duck bred for mule and that the selection of a synthetic strain was effective method of improvement.

Microneedle patch delivery to the skin of virus-like particles containing heterologous M2e extracellular domains of influenza virus induces broad heterosubtypic cross-protection

Kim, M.C.,Lee, J.W.,Choi, H.J.,Lee, Y.N.,Hwang, H.S.,Lee, J.,Kim, C.,Lee, J.S.,Montemagno, C.,Prausnitz, M.R.,Kang, S.M. Elsevier Science Publishers 2015 Journal of controlled release Vol.210 No.-

A broadly cross-protective influenza vaccine that can be administrated by a painless self-immunization method would be a value as a potential universal mass vaccination strategy. This study developed a minimally-invasive microneedle (MN) patch for skin vaccination with virus-like particles containing influenza virus heterologous M2 extracellular (M2e) domains (M2e5x VLPs) as a universal vaccine candidate without adjuvants. The stability of M2e5x VLP-coated microneedles was maintained for 8weeks at room temperature without losing M2e antigenicity and immunogenicity. MN skin immunization induced strong humoral and mucosal M2e antibody responses and conferred cross-protection against heterosubtypic H1N1, H3N2, and H5N1 influenza virus challenges. In addition, M2e5x VLP MN skin vaccination induced T-helper type 1 responses such as IgG2a isotype antibodies and IFN-γ producing cells at higher levels than those by conventional intramuscular injection. These potential immunological and logistic advantages for skin delivery of M2e5x VLP MN vaccines could offer a promising approach to develop an easy-to-administer universal influenza vaccine.

Experimental infection of mandarin duck with highly pathogenic avian influenza A (H5N8 and H5N1) viruses

Kang, H.M.,Lee, E.K.,Song, B.M.,Heo, G.B.,Jung, J.,Jang, I.,Bae, Y.C.,Jung, S.C.,Lee, Y.J. Elsevier Scientific Pub. Co 2017 Veterinary microbiology Vol.198 No.-

<P>A highly pathogenic avian influenza (HPAI) H5N8 virus was first detected in poultry and wild birds in South Korea in January 2014. Here, we determined the pathogenicity and transmissibility of three different clades of 1-15 viruses in mandarin ducks to examine the potential for wild bird infection. H5N8 (Glade 2.3.4.4) replicated more efficiently in the upper and lower respiratory tract of mandarin ducks than two previously identified H5N1 virus clades (clades 2.2 and 2.3.2.1). However, none of the mandarin ducks infected with H5N8 and H5N1 viruses showed severe clinical signs or mortality, and gross lesions were only observed in a few tissues. Viral replication and shedding were greater in H5N8-infected ducks than in H5N1-infected ducks. Recovery of all viruses from control duck in contact with infected ducks indicated that the highly pathogenic H5 viruses spread horizontally through contact. Taken together, these results suggest that H5N8 viruses spread efficiently in mandarin ducks. Further studies of pathogenicity in wild birds are required to examine possible long-distance dissemination via migration routes. (C) 2016 Elsevier B.V. All rights reserved.</P>