1.

論文(リポジトリ)

論文(リポジトリ)
岩崎, 健 ; 金城, 千順 ; 日越, 博信 ; Iwasaki, Ken ; Kinjoh, Chiyori ; Higoshi, Hironobu
出版情報: 琉球大学農学部学術報告 = The Science Bulletin of the Faculty of Agriculture. University of the Ryukyus.  pp.9-16,  2004-12-01.  琉球大学農学部
URL: http://hdl.handle.net/20.500.12000/3561
概要: ホルスタイン種新生子牛(呼称A子牛,B子牛)とその親牛(A親牛,B親牛),ならびに子牛の飼育環境(飼槽,床,櫓下,牛床,おかくず,給水器,周囲で飼育されていた牛<C子牛,D子牛,E親牛,F親牛>)から分離した大腸菌株のうち,7薬 剤[アンピシリン(ABPC),クロラムフェニコール(CP),クロルテトラサイクリン(CTC),カナマイシン(KM),ストレプトマイシン(SM),ナリジクス酸(NA),スルファジメトキシン(SA)]に対する薬剤感受性試験で,3種以上の薬剤に耐性を示した多剤耐性大腸菌120株(A子牛由来36株,B子牛38株,A親牛6株,B親牛12株,飼育環境28株)について,プラスミドプロファイルおよびパルスフィールドゲル電気泳動(PFGE)法による分子疫学的解析を行い,若葉株間の関連性を検討した.1.供試菌株におけるプラスミドDNA保有率は65%(78株/120株)で,各菌株が保有するプラスミドDNAの種類と数に基づき,プラスミドプロファイルをI型からIX型の9種類に分類できた.このうち,VII型が最も検出率が高く,A子牛,A親牛,飼育環境など広域に分布していた.親子別のプラスミドプロファイル分布状況をみると,A親牛ではVII型の1種類に対し,A子牛ではII,III,VII型の3種類,B親牛でIV型,VI型の2種類に対し,B子牛ではI,III,IV,V型の4種類が確認できた.子牛は親牛よりも多彩なプロファイルを有しており,飼育環境とは異なるプロファイルを示していた.2.プラスミドプロファイルをA,B各親子間で比較すると,A子牛由来である菌株の一部は,プロブァイルの型(VII型)が,A親牛に出来するすべての菌株と一致しており,またB子牛由来である菌株の一部は,プロファイル型(IV型)が,B親牛由来の過半数の菌株と一致していた.一方,子牛房内設備やその近傍で飼育されている成牛や子牛などの環境由来の菌株では,そのプロファイル型がVII型に集中しており,プラスミドプロファイルの分布に偏りが認められた.また,環境由来菌株で大半を占めたVII型は,A子牛由来の一部の菌株とも一致していた.3.PFGE法では供試した120株から49種類の泳動パターンが認められ,A子牛出来の菌株と非京に近縁度の高い菌株が,床,飼槽,おかくず,給水器などの子牛房内設備や,子牛房近傍で飼育されている子牛から分離された.一方,B子牛由来の菌株と近縁関係にある菌株は,今目調査したB親牛,A子牛,A親牛,子牛房内設備のいずれからも分解されなかった.また,A,B各親子間に近縁度の高い菌株は認められなかった.<br />Of all Escherichia coli isolates that were obtained from 2 newborn Holstein calves (designated calf A and B), two cows (designated cow A and B, respectively), and calf-breeding areas (trough, floor, fence, litter bed, sawdust, water trough, Holstein cattle breeding area around < calves C and D, and cows E and F>), a total of 120 multidrug resistant E. coli isolates with resistance toat least 3 out of 7 tested antibiotics [ampicillin, chloramphenicol, chlortetracycline, kanamycin, streptomycin, nalidixic acid, and sulfadimethoxine] were obtained in 2002. Each isolate was tested for clonal relationships by plasmid profile analysis and/or pulsed-field gel electrophoresis (PFGE) analysis. Plasmids were found in 65% (78/120) of all E. coli isolates tested. A total of 9 different plasmid profiles (i.e., type I-IX) were identified based on the number and size of the plasmids. Type VII was the most widely distributed type in strains from various sources, including calf A, cow A, and calf-breeding areas. The number and type of plasmid profile observed in each Holstein was: calf A, 3 types (II, III, and VII); cow A, one type (VII); calf B, 4 types (I, III, IV, and V); cow B, 2 types (IV and VI). These results show that the calves had more varied profiles than the cows, and that both calves also carried E. coli strains with plasmid profiles that were different from those of the calf-breeding areas. PFGE following restriction digestion with Xbal was performed on 120 of the isolates, because approximately one-third of the isolates did not carry plasmids and could not be typed by plasmid profile analysis. The 120 isolates were divided into 49 PFGE patterns, which showed that some genetically indistinguishable isolates were present in calf A and calf-breeding areas (floor, trough, sawdust, calf C, or calf D), and some genetically closely related isolates were also present in calf A and calf-breeding areas (floor, trough, sawdust, or water trough). Furthermore, none of the indistinguishable or closely related isolates were shared between calf A and cow A, or calf B and cow B, respectively. These results indicate that there may be other environmental sources, besides the calf-breeding areas (floor, trough, sawdust, water trough, calf breeding locations) identified in this study, that are potential sources of multidrug-resistant E. coli infection in newborn Holstein calves. 続きを見る
2.

論文(リポジトリ)

論文(リポジトリ)
岩崎, 健 ; 鮫島, 好美 ; 下門, 奈月 ; 日越, 博信 ; Iwasaki, Ken ; Samejima, Yoshimi ; Shimojoh, Natsumi ; Higoshi, Hironobu
出版情報: 琉球大学農学部学術報告 = The Science Bulletin of the Faculty of Agriculture. University of the Ryukyus.  pp.53-59,  2003-12-01.  琉球大学農学部
URL: http://hdl.handle.net/20.500.12000/3595
概要: 今回、2組のホルスタイン種親牛(A親牛およびB親牛)の分娩後1日目と7日目と、各子牛(A子牛およびB子牛)の出生後1日目から7日目までに分離した直腸便由来大腸菌252株(A子牛102株、B子牛90株、A親牛30株、B親牛30株)について、A BPC、CP、CTC、KM、SM、NA、およびSAの7薬剤に対する感受性試験を行い、耐性菌については伝達性Rプラスミドの保有状況を調査した。1)供試菌株の69%(173/252株)が薬剤耐性を示した。個体別による耐性菌検出率の平均は、A親牛20%に対してA子牛で61%、一方B親牛80%に対してB子牛90%と、いずれも親牛より子牛で高率に耐性菌が検出された。生後1日目の子牛では、A子牛47%、B子牛93%とすでに高率に耐性が認められ、生後4日目以降に耐性菌検出率がさらに増加した。2)薬剤耐性菌を薬剤別でみてみると、A親牛は4薬剤(ABPC、CTC、SM、およびSA)、B親牛は5薬剤(CP、CTC、SM、NA、およびSA)でのみ耐性菌が検出された。各子牛ではすでに1日目で親牛と同じ薬剤に耐性を示し、産後日数の経過とともに親牛では認められなかった薬剤にも耐性を示した。A子牛では2日目で他の3薬剤(CP、KM、およびNA)に、B子牛では5日目で他の1薬剤(ABPC)に耐性を示す一方、KMへの耐性は生後7日目まで認められなかった。3)薬剤耐性型をみると、A親牛で3剤型だけの2種類、B親牛で単剤型から4剤型までの5種類に対して、A子牛で単剤型から7剤型まで12種類、B子牛で単剤型から5剤型までの12種類と、子牛の薬剤耐性型が親牛よりも明らかに多かった。両子牛とも1日目で各親牛とは異なる耐性型が認められ、生後1日目から3日目までは単剤型が、4日目以降になると多剤耐性型が優勢となった。4)76株の薬剤耐性菌(A親牛6株、A子牛28株、B親牛11株、B子牛31株)について、伝達性Rプラスミドの保有状況を調査した。伝達性Rプラスミド保有菌はいずれも子牛のみから検出され、A子牛では4日目に単剤(ABPC)伝達性1株と3剤(ABPC-CP-CTC)伝達性1株、6日目に単剤(ABPC)伝達性1株が認められた。B子牛では3日目に2剤(CTC-SA)耐性型の1株だけが認められた。本調査を遂行するにあたり、御協力を頂いた沖縄県畜産試験場の各位に深謝いたします。<br />A total of 252 Escherichia coli isolates were recovered from rectal swabs of two Holstein cows (designated cow A and B) on postpartum days 1 and 7 and the female calf of each (designated calf A and B, respectively) on postnatal days 1-7. Each isolate was tested for susceptibility to 7 antibiotics [ampicillin (ABPC), chloramphenicol (CP), chlortetracycline (CTC), kanamycin (KM), streptomycin (SM), nalidixic acid (NA), and sulfadimethoxine (SA)] and for prevalence of conjugative R-plasmids. The results of these studies are: 1. Resistance to at least one of antibiotics tested was found in 69% (173/252) of the E. coli isolates. The mean frequency of resistant isolates was: cow A, 20%; calf A, 61%; cow B, 80%; and calf B, 90%. These results show that calves are readily infected with resistant bacteria: on postnatal day 1, 47% of the E. coli isolates from calf A and 93% from calf B were antibiotic-resistant. Furthermore, the fraction of isolates that were antibiotic-resistant increased after postnatal day 3. 2. On postpartum day 7, isolates with resistance to only 4 of the antibiotics tested (ABPC, CTC, SM, and SA) were obtained from cow A and to only to 5 of the antibiotics (CP, CTC, SM, NA, and SA) from cow B. On postnatal day 1, both calves already had isolates with the same-antibiotic resistances as the corresponding cow. By postnatal day 2, isolates from calf A were also resistant to the other 3 antibiotics (CP, KM, and NA). Isolates resistant to one of the other antibiotics (ABPC) were found in calf B by postnatal day 5, but no isolate to the remaining antibiotic (KM) was found in calf B by postnatal day 7. 3. A number of antibiotic resistance patterns were found, ranging from isolates resistant to a single antibiotic to isolates resistant to multiple (i. e., 2-7) antibiotics. Isolates from calves had more resistance patterns than those from cows, and no isolates from cows were resistant to more than 4 antibiotics. On postnatal day 1, isolates from both calves already had different resistance patterns than those from the corresponding cow. Isolates with resistance to a single antibiotic were predominant during postnatal day 1-3. However, after postnatal day 3, isolates with resistance to multiple antibiotics were predominant. 4. The prevalence of a conjugative R-plasmid was investigated in 76 of the antibiotic-resistant isolates; 6 from cow A, 28 from calf A, 11 from cow B, and 31 from calf B. Conjugative R plasmid transfer was found in 4 of these isolates: a day 4 postnatal isolate from calf A with resistance to 1 antibiotic (ABPC), a day 6 postnatal isolate from calf A with resistance to 1 antibiotic (ABPC), a day 4 postnatal isolate from calf A with resistance to 3 antibiotics (ABPC-CP-CTC), and a day 3 postnatal isolate from calf B with resistance to 2 antibiotics (CTC-SA). 続きを見る
3.

論文(リポジトリ)

論文(リポジトリ)
日越, 博信 ; 田中, こころ ; 田中, 志津香 ; 平川, 守彦 ; Higoshi, Hironobu ; Tanaka, Kokoro ; TaNaka, Shizuka ; Hirakawa, Morihiko
出版情報: 琉球大学農学部学術報告 = The Science Bulletin of the Faculty of Agriculture. University of the Ryukyus.  pp.29-35,  1999-12-01.  琉球大学農学部
URL: http://hdl.handle.net/20.500.12000/3661
概要: 動物病院で診療を受けた,受診犬(27頭)及び受診猫(13頭),動物愛護センターで引き取られるか,捕獲された犬(20頭)及び猫(24頭),計84頭から分離された大腸菌776株について,ABPC,CP,CTC,KM,SM,NA,SAの7薬剤に対 する感受性試験を行った。また耐性菌については,伝達性Rプラスミドの検索を行った。7薬剤のいずれかに耐性であった大腸菌は,犬では102株(24.7%),猫では59株(16.3%)であった。犬の耐性菌検出率では,受診犬(24.0%)と捕獲犬(25.5%)がほぼ同率であったが,猫では受診猫26.8%に対し,引取猫10.6%で,前者が高率であった。薬剤別の検出率は,犬ではCTC耐性が17.7%で最高,以下SA,SM,ABPC耐性の順であり,猫ではSA耐性が12.6%で最高,以下ABPC,CTC,SM耐性の順であった。捕獲犬は受診犬に比較して,すべての薬剤において検出率が高かったが,猫では逆にすべての薬剤で受診猫の方が引取猫より高かった。耐性型は,犬では単剤型から6剤型まで23種類(捕獲犬22種類,受診犬10種類),猫では単剤型から7剤型まで9種類(引取猫6種類,受診猫4種類)であった。受診犬は単剤型と2剤型で73%を占めたが,捕獲犬では3剤型以上が60%に達した。猫では,引取猫の過半数が単剤型と2剤型であったのに対し,受診猫は7剤型のみで62%を占めた。耐性菌における伝達性Rプラスミド保有菌の検出率は,犬が6.1%,猫が35.7%であった。猫では殆どが2剤伝達性であったが,犬では単剤伝達性が殆どであった。<br />Tests for sensitivity to seven drugs were conducted on 776 strains of Escherichia coli isolated from a total of 84 dogs and cats; 27 dogs and 13 cats referred to an animal hospital for treatment (referred group) and 20 dogs and 24 cats taken over or captured by animal protection centers (captured group). In the resistant strains, transferable R plasmid were studied. Resistance to at least one of the 7 drugs was found in 102 (24.7%) of strains obtained from dogs and 59 (16.3%) of strains obtained from cats. The percentage of resistant strains was 24.0% from referred dogs and 25.5% from captured dogs. The corresponding values were 26.8% in referred cats and 10.6% in captured cats. In dogs, the rate of resistance was the highest for CTC (17.7%) followed by SA, SM and ABPC in decreasing order. In cats, the rate of resistance was the highest for SA (12.6%) followed by ABPC, CTC and SM. The rate of drug resistance was higher for each drug in captured dogs than in referred dogs, but higher for each drug in referred cats than in captured cats. As to the range of multiple resistance, 23 combinations ranging from resistance to a single drug to 6 drugs were found in dogs (22 combinations in captured dogs and 10 combinations in referred dogs), whereas 9 combinations ranging from resistance to a single drug to all 7 drugs were found in cats (6 combinations in captured cats and 4 in referred cats). In referred dogs, resistance to 1 or 2 drugs accounted for 73%, whereas resistance to 3 or more drugs accounted for 60% in captured dogs. More than half of the strains from captured cats showed resistance to only 1 or 2 drugs, whereas strains resistant to all 7 drugs accounted for 62% from referred cats. Resistant strains with transferable R plasmid were found in 6.1% of dogs and 35.7% of cats. While 2 drug transfer was mostly found in cats, single drug transfer was mostly found in dogs. 続きを見る
4.

論文(リポジトリ)

論文(リポジトリ)
日越, 博信 ; 宮城, 寿満子 ; 諸見里, 淳子 ; 平川, 守彦 ; Higoshi, Hironobu ; Miyagi, Sumako ; Moromizato, Junko ; Hirakawa, Morihiko
出版情報: 琉球大学農学部学術報告 = The Science Bulletin of the Faculty of Agriculture. University of the Ryukyus.  pp.35-41,  1998-12-01.  琉球大学農学部
URL: http://hdl.handle.net/20.500.12000/3682
概要: 沖縄県内のヤギ飼養農家22戸, 73頭の糞便由来大腸菌合計822株について, 7薬剤に対する感受性試験を, また耐性菌については伝達性Rプラスミドの検索も行った。これらの成績を給与飼料別(野草のみと野草+穀類), 地域別(北部と南部)に比較 した。7薬剤のいずれかに耐性の大腸菌は, 全体では147株(17.9%)であった。給与飼料別の検出率では野草のみが17.2%, 野草+穀類が18.7%でほぼ同率であった。しかし, 野草のみでは北部31.8%, 南部5.7%で, 前者が高率であったのに対し, 野草+穀類では北部17.8%, 南部19.2%でほぼ同じであった。薬剤別ではCTC耐性が11.3%で最高, 以下SA, ABPC, SM, KM, CP耐性の順であり, NA耐性は検出されなかった。野草のみでは, CTC耐性が両地域とも1位の検出率を示したが, 野草+穀類では, 北部でCTC耐性が1位を, 南部でABPC耐性とSA耐性が同率1位を示すなど, 若干異なった。耐性型の種類は, 全体では5剤型を除く単剤型から6剤型まで17種類認められた。野草のみでは北部6種類, 南部8種類, 野草+穀類ではそれぞれ3種類と6種類であり, いずれも南部が多かった。また6剤型は南部の野草+穀類でのみ検出された。野草+穀類では2剤以上の薬剤に耐性の多剤耐性型が大多数を占め, 特に南部の全株が多剤耐性型であったが, 野草のみでは50&acd;56%が逆に単剤型であった。耐性菌147株のうち, 17株(11.6%)が伝達性Rプラスミドを保有し, 野草のみ9株(北部8株, 南部1株), 野草+穀類8株(南部のみ)であった。これら菌株の伝達耐性型は, 野草のみの9株がCTC単剤伝達性, 野草+穀類では5株がSM単剤伝達性, 3株がSM-SA2剤伝達性であった。<br />We performed sensitivity tests to seven antibiotics on a total of 822 strains of Escherichia coli isolated from the feces of 73 goats from 22 goat farms in Okinawa prefecture. Transmissible R-plasmids were also examined in antibiotic-resistant strains. These results were compared by type of feed (grass only, or mixed feed of grass and concentrated feed) and by district (south or north). A total of 147 strains (17.9%) were resistant to at least one of the seven antibiotics. The detection rates of resistant strains were similar in the grass only group (17.2%) and the mixed feed group (18.7%). However, in the grass only group, the resistance rate was higher in the northern district (31.8%) than in the southern district (5.7%); while in the mixed feed group, the rates in the northern (17.8%) and southern districts (19.2%) were similar. The detection rate of CTC resistance was highest (11.3%), followed by SA, ABPC, SM, KM and CP resistance, with no NA resistance. In the grass only group, the detection rate of CTC resistance was the highest in both the northern and southern districts, whereas in the mixed feed group, CTC resistance was the highest in the northern district, but ABP^4C resistance and SA resistance were the highest in the southern district; showing some difference. Seventeen patterns of resistance were observed, ranging from single-drug to 6-drug resistance, except 5-drug resistance. Six-drug resistance was observed only in the mixed feed group in the southern district. The predominant resistance pattern in the mixed feed group was multiple resistance to 2 or more antibiotics; particulaly, all the resistant strains in the southern district were multiple resistant strains. In contrast, 50 to 56% of the resistant strains in the grass only group showed single-drug resistance. Seventeen of 147 resistant strains (11.6%) caried R-plasmids. Nine strains were isolated from the grass only group (8 strains in the north and 1 strain in the south). The transmissible resistance types were CTC only in 9 strains in the grass only group; SM only in 5 strains and SM-SA in 3 strains in the mixed feed group. 続きを見る
5.

論文(リポジトリ)

論文(リポジトリ)
平川, 守彦 ; 富名腰, 道子 ; 日越, 博信 ; 大城, 政一 ; 石嶺, 行男 ; 平山, 琢二 ; 赤嶺, 光 ; 外間, 聡 ; Hirakawa, Morihiko ; Funakoshi, Michiko ; Higoshi, Hironobu ; Oshiro, Seiichi ; Ishimine, Yukio ; Hirayama, Takuji ; Akamine, Hikaru ; Hokama, Satoshi
出版情報: 琉球大学農学部学術報告 = The Science Bulletin of the Faculty of Agriculture. University of the Ryukyus.  pp.43-51,  1998-12-01.  琉球大学農学部
URL: http://hdl.handle.net/20.500.12000/3683
概要: 本研究は, 放牧地空間を有効利用するために, 放牧草地生態系へ熱帯果樹を導入することによって, 肉生産と果樹生産の両立をはかることを目的としている。昨年放牧牛による食害防御法が確立されたことからその方法であるワイヤーメッシュケージ法を継続し て行ない, さらに果樹の生長, 果実の生産に向けて生育状況を把握するとともに効率良く生産をおこなうため, 放牧地の種々の光条件下と地形の違いによる果樹の生育について調査, 検討を行なった。昨年からのワイヤーメッシュケージ法を継続して行ない, グアバとビワのうち枯死していないもの(グアバ96本・ビワ64本)を調査に用いた。供試家畜は, 黒毛和種の成牛4頭と子牛4頭の合計8頭を用いた。グアバ, ビワの両果樹それぞれについて相対照度を測定し, 相対照度が100%&acd;65%の所をH区, 相対照度が65%&acd;35%の所をM区, 相対照度が35%以下となる所をL区と設定し, グアバについてはさらに傾斜角度が約35度の北西斜面の傾斜地をN区と設定した。調査項目は, 放牧牛による果樹の被食率, 麻袋被害率, 果樹の葉数, 果樹の樹高で, 調査期間は6月から12月までで1ヶ月間隔で調査を行なった。ワイヤーメッシュケージを継続して行なったところ, 調査期間全体を通して両果樹とも放牧牛による被食率は0%であった。麻袋被害率についてもほとんど0%であったが調査期間中の平均被害率がグアバ区で7.7%, ビワ区で0.6%と有意な差が認められた。相対照度の調査において, グアバではH区で葉数, 樹高ともに一番高い値を示し, L区で葉数,樹高ともに有意に低い値が認められた。グアバ区では病害虫の発生もみられ生長は思わしくなかった。ビワではL区で葉数, 樹高ともに一番高い値を示した。ビワ区ではわずかではあるが生長が認められた。両果樹について台風による被害がみられた。<br />We had studied on the introduction of tropical fruit tree in grazing pastute to produce both beef and tropical fruits because of utilization space in grasslands. We reported that several methods were conducted to introduce various tropical fruit trees (papaya, guava, loquat) in grasslands. We established the protection method for fruit trees from grazing cat tle; that was the wire-mesh cage method surrounded tropical tree by the wiremesh cage. So we continued the study to investigate the growth of guava and loquat using this method under various intensity of illuminations and topography. A guava (Psidium guyava L.) and loquat (Eriobtrya japonica Lindley) were transplanted in 1996. Eight heads of Japanese black cattle; four cows and four calves were grazed in grassland. The grasslands with the guava and loquat trees were divided into three plots of intensity of illuminations which were high intensity of 100-65% (H), of midium intensity of 65-35% (M), and of less than 35% (L), and then plotted the northwest-facing slope plot (N) in grasslnad with guava trees. We investigated the ratio of damage of fruit trees and of mulching materials (used linen bags) under the trees by grazing catlle, number of their leaves and height of trees from June to December every month. Tropical fruit trees were not entirely injured by grazing cattle during whole experimental periods by wire-mesh cage method. However, there was a small damage of mulching linen bags in guava area (7.7%) and loquat area (0.6%), it was singnificant at 5% level. The number of leaf and the height of guava were the highest in the high intensity of illumination area, but their values were lower in the less than 35% area. Only guava trees were damaed by insects (larvae of moth). On the contrary the number of leaf and the height of loquat trees showed the highest value in the intensity of illumination of less than 35% area. We found a typhoon da-maged the guava and loquat furuit trees. 続きを見る
6.

論文(リポジトリ)

論文(リポジトリ)
日越, 博信 ; 親里, 真理子 ; 宮平, 良成 ; 平川, 守彦 ; Higoshi, Hironobu ; Oyasato, Mariko ; Miyahira, Yoshinari ; Hirakawa, Morihiko
出版情報: 琉球大学農学部学術報告 = The Science Bulletin of the Faculty of Agriculture. University of the Ryukyus.  pp.131-138,  1997-12-01.  琉球大学農学部
URL: http://hdl.handle.net/20.500.12000/3701
概要: 沖縄本島内の一養鶏場で産卵鶏の日齢別に採取した糞便由来大腸菌合計826株について, 7薬剤に対する感受性試験を行い, また耐性菌については伝達性Rプラスミドの検索も試みた。供試した7薬剤のいずれかに耐性の大腸菌は, 314株(38.0%)で あった。日齢別の耐性菌検出率では20日齢が86.9%で最高, 600日齢が8.8%で最低であり, 加齢に伴い低下する傾向を示した。しかし, 500日齢では51.7%を示し, 20日齢に次いで高い値であった。薬剤別ではSA耐性が29.7%で最高, 以下SM, CTC, KM, ABPC耐性などの順であった。各日齢ともSA耐性が1位または2位の検出率を示したが, 200日及び400日齢ではCTC耐性が1位を, また800日齢ではABPC耐性とSA耐性が同率で1位を示すなど, 日齢によって検出順位が異なった。耐性型の種類は, 全体では単剤型から6剤型まで23種類認められたが, 20日齢では16種類, 他の日齢では7種類以下であった。また2剤以上の薬剤に耐性の多剤耐性型が約70%を占め, 特に20日齢では90%が多剤耐性型であり, 6剤型も本日齢のみで検出された。なお200日, 500日及び800日齢でも59&acd;77%が多剤耐性型であった。耐性菌314株における伝達性Rプラスミドの検索では, 60株(19.1%)がRプラスミドを保有していたが, うち47株は500日齢由来であった。300日, 400日及び800日齢ではRプラスミド保有菌が検出されなかった。これら菌株の伝達耐性型は単剤型から4剤型まで見られたが, 49株が単剤伝達型であり, 残りの2&acd;4剤伝達型は20日及び500日齢由来であった。<br />Fecal samples were collected from laying hens at various ages in a poultry farm in Okinawa Prefecture. A total of 826 strains of Escherichia coli were isolated from the samples and tested for sensitivity testing to 7 antibiotics. Transmissible R plasmid was investigated in the resistant strains. Three hundred and fourteen strains (38.0%) were resistant to at least one of the 7 antibiotics tested. The prevalence of resistant strains was highest in the 20-day-old group (86.9%) and lowest in the 600-day-old group (8.8%), with a tendency of decrease with age. However, the prevalence was still 51.7% in the 500-day-old group, the second highest after the 20-day-old group. The rate of SA resistance was highest at 29.7%, followed by SM, CTC, KM and ABPC, in that order. SA resistance was the highest or second highest in all age groups, but CTC resistance was the highest in the 200-and 400-day-old groups, and ABPC and SA resistance was high in the 800-day-old group. The order of resistance rate among antibiotics varied slightly with age. Twenty-three resistance patterns were detected ranging from single-agent to 6-agent resistance. Sixteen types were observed in the 20-day-old group and 7 types or less in the other age groups. Multiple resistance type, defined as resistance to 2 or more antibiotics, accounted for approximately 70%. In the 20-day-old group, particularly, 90% were of the multiple resistance type and 6-agent resistance was seen only in this age group. Transmissible R plasmid was investigated in 314 resistant strains. Sixty strains (19.1%) possessed R plasmid, 47 strains of which were from the 500-day-old group. No R plasmid possessing strain was detected in the 300-, 400-or800-day-old group. 続きを見る
7.

論文(リポジトリ)

論文(リポジトリ)
平川, 守彦 ; 浜田, 孝介 ; 日越, 博信 ; 大城, 政一 ; 平山, 琢二 ; 石嶺, 行男 ; 赤嶺, 光 ; 外間, 聡 ; Hirakawa, Morihiko ; Hamada, Kosuke ; Higoshi, Hironobu ; Oshiro, Seiichi ; Hirayama, Takuji ; Ishimine, Yukio ; Akamine, Hikaru ; Hokama, Satoshi
出版情報: 琉球大学農学部学術報告 = The Science Bulletin of the Faculty of Agriculture. University of the Ryukyus.  pp.139-146,  1997-12-01.  琉球大学農学部
URL: http://hdl.handle.net/20.500.12000/3702
概要: 本研究は放牧草地の立体空間を有効利用するために熱帯果樹を植えて肉生産と果樹生産を同時に行おうとするもである。しかし, 放牧牛は草以外に苗木も採食してしまうので果樹の生育に大きなダメージを与え, 枯死に至らしめることもある。本実験は放牧牛によ る熱帯果樹苗木の食害を牛の嫌がる臭いによって防御した。実験は3段階に分けて行った。第1実験は薬品の食害に対する効果を検討した。薬品は酪酸, アンモニア, トリメチルアミン, プロピオン酸, ブチルメルカプタンの5種類を用い, それぞれを脱脂綿に浸し, 加工ポリ容器に入れ支柱に吊り下げて食害防御効果の高い薬品を選抜した。第2実験は, 第一段階で選抜した薬品(酪酸)の設置方法を検討した。麻袋法, ボトル法, 麻袋法とボトル法の同時設置法(麻袋法+ボトル法)の3方法で選抜した。第3実験は第1,第2段階で最も効果のあった薬品および設置方法を選択し, 選定した薬品の希釈倍率を50倍, 100倍, 200倍の3水準で忌避効果を調べた。薬品選抜試験では酪酸による防御効果が最も高かった。ついで, ブチルメルカプタン, トリメチルアミン, アンモニア, プロピオン酸, 無処理の順であった。薬品設置法の試験では, ボトル法, ボトル法+麻袋法の2処理が同程度の効果を示し, 麻袋法においては食害率が高かった。薬品の希釈倍率では50倍希釈と100倍希釈が同程度の効果を, 200倍希釈はそれらよりも約2倍も高い果樹被食率を示した。以上の結果から100倍希釈の酪酸を脱脂綿に浸してボトル法(ポリ容器)により苗木のすぐそばに設置したほうが食害の防御効果の高いことがわかった。<br />We studied the production of both beef and tropical fruits in same place to utilize the spatial space in grassland. It occurred that tropical fruit trees in grassland were eaten by grazing cattle, and they will be ceasing to grow soon. In this study we tried to protect the tropical fruit trees from grazing cattle by means of odoriferous materials in grassland. Papaya (Carica papaya L.) which cultivated in pods until 40 to 50cm height in green house transplanted in grassland. Three experiments were conducted. Following experiments on protecting tropical fruit tree from grazing cattle were made : 1. Effects of five kinds of odoriferous materials (butyric acid, ammonia, trimethylamine, propionic acid, butylmercaptan) which put in processed polyethylene resin bottles with absorbent cotton on protecting fruit tree from grazing cattle; 2. Effects of three setting methods (that is, there are method of heap cloth mat soaked butyric acid under the fruit tree, of polyethylene resin bottle, and of heap cloth mat added polyethylene resin bottle) of using butyric acid which was most effective in experiment one on protection fruit tree from grazing cattle; 3. Effects of three concentration levels of diluted 50,100 and 200 times butyric acid solution on protecting fruit tree from grazing cattle. The results obtained were as follows. The most effective odor material which protected tropical fruit tree from grazing cattle was butyric acid, and were higher effect in order of butylmercaptan, trimethylamine, ammonia, propionic acid and no-odor material. In means of setting experiment polyethylene resin bottle method was same effectiveness as heap cloth mat added polyethylene resin bottle method. 続きを見る
8.

論文(リポジトリ)

論文(リポジトリ)
平川, 守彦 ; 野辺, 晃 ; 日越, 博信 ; 大城, 政一 ; 平山, 琢二 ; 石嶺, 行男 ; 赤嶺, 光 ; 外間, 聡 ; Hirakawa, Morihiko ; Nobe, Akira ; Higoshi, Hironobu ; Oshiro, Seiichi ; Hirayama, Takuji ; Ishimine, Yukio ; Akamine, Hikaru ; Hokama, Satoshi
出版情報: 琉球大学農学部学術報告 = The Science Bulletin of the Faculty of Agriculture. University of the Ryukyus.  pp.147-151,  1997-12-01.  琉球大学農学部
URL: http://hdl.handle.net/20.500.12000/3703
概要: 本研究は放牧地の空間を有効利用するために放牧草地生態系へ熱帯果樹を導入し, 肉生産と果樹生産の両立について検討しようとするものである。本試験においては食害防御効果をさらに高めるために市販のポリネット袋を用いて, 物理的な方法による果樹食害防 御の検討を行った。熱帯果樹にはパパヤを用い, 供試家畜には黒毛和種経産牛3頭, 11ヶ月齢の雌牛2頭, 3ヶ月齢の雌牛2頭の計7頭を放牧した。パパヤ苗は放牧地に約4m間隔で移植し, 長さ約1.5mの支柱を苗の両側に1本ずつ立てた。そして, 縦75cm, 横42cmの市販のポリネット袋で苗を被覆した。その後, 供試牛を放牧し, 1日1回パパヤの被食率を調査した。ポリネット試験は第1期10月25日&acd;11月3日(10日間), 第2期11月25日&acd;12月2日(8日間)行った。1日平均被食率は無処理区で16%, ポリネット処理区で3.4%であった。ポリネット処理区における放牧牛による食害の特徴はポリネットの上から葉身を咀嚼するためダメージは少なく枯死に至るほどではなかった。以上の結果より, ポリネット処理区は無処理区に比べ放牧牛によるパパヤの被食が最も低く, 食害防御効果の高いことがわかった。<br />The purpose of this study is to produce both beef and tropical fruits in same place where we will utilize the spatial space of grassland effectively. In the study we carryied out the polyethylene-net bag method to protect tropical fruit tree from grazing cattle. We used papaya (carica papaya L.) as tropical fruit tree, and grazed seven japanese black cattle, that is three cows, two heifers of eleven months age and two heifers of three months age. Papaya transplanted in each four meter intervals, and struck supports which made of iron with 1.5m height in each sides of fruit tree. The size of polyethylene-net bag that was covered tropical fruit tree was seventy-five by forty-two centimeters. We measured ratio of damaged papaya trees every day during experiments. Experiment of the polyethylene-net bag method were conducted two times which were from twenty-fifth of October to third of November and from twenty-fifth of November to 2nd of December. It were shown the mean ratio of damaged fruit trees per day in nontreatment and polyethylene-net bag method were percent of 16 and 3.4 respectively. A characteristics of damaged papaya tree in polyethylene-net bag method did not receive a serious injury because of chewing papaya tree on the polyethylene-net bag. From the results described above, we might conclude that the polyethylene-net bag method was useful to protect tropical fruit tree from grazing cattle. 続きを見る
9.

論文(リポジトリ)

論文(リポジトリ)
日越, 博信 ; 平川, 守彦 ; 蓮尾, 環 ; 大城, 政一 ; 石嶺, 行男 ; 平山, 琢二 ; 赤嶺, 光 ; 外間, 聡 ; Higoshi, Hironobu ; Hirakawa, Morihiko ; Hasuo, Tamaki ; Oshiro, Seiichi ; Ishimine, Yukio ; Hirayama, Takuji ; Akamine, Hikaru ; Hokama, Satoshi
出版情報: 琉球大学農学部学術報告 = The Science Bulletin of the Faculty of Agriculture. University of the Ryukyus.  pp.153-159,  1997-12-01.  琉球大学農学部
URL: http://hdl.handle.net/20.500.12000/3704
概要: 本研究は放牧地の立体空間を有効利用するために放牧草地生態系へ熱帯果樹を導入し, 肉生産と果樹生産を行おうとするものである。本試験において, 食害防御効果を高めるために金網ネットを用いた物理的な方法による熱帯果樹の食害防御法の検討を行った。熱 帯果樹にはグアバとビワを用いた。供試家畜は黒毛和種経産牛3頭(平均体重370kg), 未経産牛4頭(生後17&acd;22ヶ月齢)の合計7頭を放牧した。グアバとビワの苗は放牧地に約4m間隔で移植し, 長さ1.5mの支柱を苗の両側に立て, 上からネット袋で苗を被覆し供試牛を放牧した。退牧時にグアバとビワの被食率とネットの被害率を調査した。ネット試験を2回終了した時点でネットを取り外し, 苗の四方に支柱を4本立て, その支柱に金網ネットを張り巡らし固定した。ネット試験と同様に6回の放牧試験を行った。試験期間は7月から1月までの8ヶ月で8回の放牧試験を行った。1日平均果樹被食率はグアバのネット処理区で4.3%, 金網ネット処理区で1.6%, ビワのネット処理区で1.9%, 金網ネット処理区で0.7%と両果樹とも金網ネット処理区の方が低い値を示した。この結果, 金網ネット処理区はネット処理区に比べ有意に低い値を示した。また, グアバとビワにおける被食率の差も検討したが, 有意な差は認められなかった。以上の結果より, 金網ネット処理はネット処理に比べ熱帯果樹食害防御効果の高いことがわかった。<br />We have studied to produce both beef and tropical fruit due to utilization of spatial space in grassland. In this study we attempted the method of wirenet to protect tropical fruit tree from grazing cattle. We cultivated guava and loquat as tropical fruits, and grazed seven Japanese black cattle; three cows of mean weight of 370kg, four heifers of the range from seventeen to twenty-two months. We transplanted guava and loquat at four meter intervals in grassland, and struck the steel pole which was 1.5m in length both sides of a tropical fruit tree. All the tropical fruit trees (guava, loquat) were covered with polyethylene-net bag. We investigated damage of guava and loquat by means of polyethylene-net bag method after grazing. After two times of each experiments used polyethylene-net bag were removed, and added two iron posts both sides of fruit tree. Wire-net was put tightly around four posts of tropical fruit tree. Grazing experiments of the wire-net bag method were conducted eight times from July to January in the following year. The mean ratio of damaged guava per day were shown 4.3% in polyethylene-net bag method and 1.6% in wire-net method. The mean ratio of damaged loquat per day in polyethylene-net bag method and wire-net method were shown 1.9% and 0.7% respectively. As we compared the ratio of damaged fruit tree in polyethylene-net bag method with wire-net method, its ratio was significant low in wire-net method, its ratio was significant low in wire-net method. But the ratio of damaged between guava and loquat were not significant. From the results described above, we found the wire-net method was more effective grazing protecton than the polyethylene-net bag method. 続きを見る
10.

論文(リポジトリ)

論文(リポジトリ)
平川, 守彦 ; 仲本, 裕子 ; 日越, 博信 ; 大城, 政一 ; 石嶺, 行男 ; 平山, 琢二 ; 赤嶺, 光 ; 外間, 聡 ; Hirakawa, Morihiko ; Nakamoto, Yuko ; Higoshi, Hironobu ; Oshiro, Seiichi ; Ishimine, Yukio ; Hirayama, Takuji ; Akamine, Hikaru ; Hokama, Satoshi
出版情報: 琉球大学農学部学術報告 = The Science Bulletin of the Faculty of Agriculture. University of the Ryukyus.  pp.161-165,  1997-12-01.  琉球大学農学部
URL: http://hdl.handle.net/20.500.12000/3705
概要: 本研究は, 放牧地の立体空間を有効利用するために, 放牧草地生態系へ熱帯果樹を導入して, 肉生産と果樹生産の両立を行おうとするものである。今回は, ワイヤーメッシュケージ法を用いて果樹食害防御の検討を行った。供試した熱帯果樹はグアバとビワで ある。供試家畜は, 経産牛3頭(平均体重357kg), 雄子牛3頭(10カ月齢, 平均体重238kg), 未経産牛2頭, 雄牛1頭の合計9頭で, グアバ, ビワを囲むワイヤーメッシュケージは, 鉄材を用いて1m(縦)×1m(横)×1.5m(高さ)の大きさの枠を作り, この枠に網目15cm×15cm, 大きさ1.5m×1.0mの網を園芸ロープで固定して作った。ケージは脚を地下30cmの深さに埋め込んで固定した。供試牛を数日間放牧し, 退牧時にグアバ, ビワそれぞれの被食率, ネット被害率を調査した。試験期間は8月から1月までの6カ月間で, 各果樹とも6回の放牧試験を行った。ワイヤーメッシュケージ法を用いたところ試験期間全体を通して両果樹とも被食率は0%であり,ケージ自体の被害率も常に0%であった。以上のことからワイヤーメッシュケージ法は熱帯果樹の食害を防御する方法として最良であった。<br />We have studied to produce both beef and tropical fruits due to utilization of spatial space in grassland. In this study we used wire-mesh cage method to protect tropical fruit tree from grazing cattle. We cultivated guava (Psidium guyava L.) and loquat (Eriobtrya japonica Lindley) as tropical fruits, and grazed nine Japanese black cattle; three cows of mean weight of 357kg, three steers of mean weight of 238kg, two heifer calves and bull. The wire-mesh cage which was made of frame 1 by 1 by 1.5 meter of steel pole and was then put around the frame except the top with wire-mesh of 15 by 15 centimeter were located in grassland to knock it in underground at thirty centimeter depth to protect tropical fruit trees from grazing cattle. We measured the damaged ratio of guava and loquat and of wiremesh cage after grazing. Grazing experiments of the wife-mesh cage method were conducted six times from August to January in the following year. It was wire-mesh cage method that neither guava nor loquat received damage entirely from grazing cattle during experiments. Wire-mesh cage was so tough to rub it by cattle. From the results described above, we recognized that wire-mesh cage method was the most effective grazing protection in these studies. 続きを見る