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Theoretical Study of Fitness Reduction in Stream-dwelling Fish by the Fixation of Slightly Harmful Mutations under Habitat Fragmentation
Get PDF渓流魚におけるダムや遡上阻害物による棲息地分断は上流から下流へは移動できるが下流から上流への移動を制限する。そのような偏った移動の原因となる分断が,そこに棲息する生物において,上流で固定した弱有害遺伝子が下流全体に広がる事によって固定して適応度低下を生むか,数値シミュレーションを用いて解析した。その結果,上流から下流への一方的な流下が起こる場合,上流での弱有害遺伝子の固定による悪影響は上流だけにとどまらず,遡上障害物の上下流2個体群両方に広がり,上下流2個体群の適応度は下流にどれだけ大きな個体群が存在していても,上流に単一の個体群がある場合と同程度にまで減少することが分かった。更に,この適応度低下が下流から上流への人為的な運搬によってどの程度防げるかを検討し,たとえ小規模,小頻度の運搬であっても,集団の分断が起こっていない場合と同程度までリスクが減らせるほど効果が高いことを示した。このことから,遡上阻害物による分断で上流部に小集団が生まれた場合,下流から上流への人為的な運搬や,魚道の設置が望まれる。Fragmentation of habitat can result in serious consequences for organisms. In particular for stream-dwelling fish, habitat fragmentation by dams or other artificial barriers limits their migration to only one way from upper to lower stream. This asymmetry in migration is unique to aquatic organisms and may result in problems that do not exist in terrestrial organisms. Among them, we analyze the fitness reduction by the fixation of harmful mutations using a numerical simulation model. In two population model, the fitness reduction depends almost entirely on the size of upper population, and is almost the same as one population model of a similar sized population. We show that artificial transport from lower to upper stream could greatly reduce the likelihood of the fixation of harmful mutation even if the amount or frequency of transport is small, and that the reduction of fitness becomes smaller than that without transporting. We also consider the influence of sex ratio of fish that are transported and find that it is not so large, but in the case of similar sex ratio between swimming down and transporting up, the fitness reduction becomes smaller. In conclusion, we recommend artificial transportations to upper stream over artificial dams or barriers.E2KJ00006290501論文Articl
The Possibility of Wood Biomass Usage by Line Thinning : The case of the profit sharing forest of Tokyo University of Agriculture
Get PDF木質バイオマスは,石化資源にかわる再生可能な資源の一つであり,エネルギー問題や環境問題など様々な側面から注目されている。木質バイオマス利用を考える際に,林地残材の活用が重要である。しかし,素材価格の低迷,高額な素材生産費,容易でない林地残材の集荷などの問題から,林地残材は有効利用されていない。今後は,資源の供給や活用方法だけでなく,素材価格と素材生産費の関係に注目し議論する必要がある。列状間伐は低コストかつ集約的な間伐である。また,林地残材が作業道付近に散在するので,列状間伐による木質バイオマスは,V1 (素材市場や製材工場への生産量),V2 (作業道付近の利用可能な木質バイオマス量),V3 (搬出不可能な木質バイオマス量)に分けられると考えた。そこで,東京農業大学大桁山分収林で行われた列状間伐および間伐材の流通を事例に,素材価格と素材生産費から木質バイオマス利用の可能性を考察した。分析の結果,東京農業大学大桁山分収林における対象林分(3.98ha)からの間伐材は,V1が213.138m^3で,V3をほぼ0であると仮定するとV2が189m^3となった。素材生産費の内訳は,素材の伐採・搬出・運材費が1,535,494円,作業道開設費は1,791,000円であった。しかし,作業道開設と間伐に対する補助金を活用したので,素材生産費の負担は1,607,594円(7,543円/m^3)となった。V1は収益がマイナスの材と,収益が4,560円/m^3 (久保山(2009)による他のエネルギーとの競争が可能な価格)以下の材と,収益が4,560～13,300円/m^3の材,三つに分類できた。V2材とV1材の一部を木質バイオマスとして利用すると仮定すると,1m^3あたりの素材生産費が下がり,マイナス材が減少すると推定した。本事例における木質バイオマス利用として,木質バイオマス資源への全利用という経営戦略が可能性の一つとして考えられる。Wood biomass is a renewable resource, which substitute of the petrifaction resource, and now it is receiving attention because of multiple functions, not only an energy resource but also other functions such as environment conservation. But at the practical phase, the wood biomass is difficult to use because yarding of slash is not easy, the cost and income makes reflection each other, and those resources were disposed the forest. So for the sufficient use of wood biomass, we should consider the supply and use method with strategy that considers cost and income. Line thinning is a consolidated thinning method and its cost is low, while slash lies scattered in the vicinity of the yarding road. Thus, it was considered that wood biomass from line thinning could be classified into V1 (the estimated volume shipped to the market), V2 (the estimated wood biomass left on the skidding road), V3 (volume of log remaining in the stand). So the study focuses on the possibility of wood biomass usage in terms of cost and income in the case of line thinning in the shared forest of Tokyo University of Agriculture. The results showed that the estimated total volume of thinned was 402m^3, i.e. V1 was 213m^3, i.e. V2 was 189 m^3 and i.e. V3 was not considered. Total logging cost excluding cost of yarding road construction was calculated to be 1,535,494yen, and the cost of logging road was 1,791,000yen. The final total cost of line thinning was 1,607,594yen (7,543yen/ m^3)which was deleted because of subsidy for the thinning and establishment of yarding road. According to the income by log cluster, V1 was divided into three groups ; the first income was minus, the second income was under 4,560yen (border value of the competition price by other energy that KUBOYAMA (2009) reported), and the third income was between 4,560∼13,300yen. From the site of forest management, we considered the following strategies : The first is that only V1 is used. But if it is, the cost turned out to be more whereas total income decreased. The second is that, for part of V1 and all of V2 for the wood biomass, the thinning cost turned down and the wood group whose income is minus was decreased greatly and other group's income was increased. The third is that all thinned wood is for wood biomass use. If V2 log could be use as wood biomass, total harvesting cost would decrease and minus log would also decrease. In this case study, it was recommended to apply for wood biomass use, a portion of the logs or total logs due to a few high benefit if there are demands on wood biomass. So if we consider the possibility of biomass use by line thinning in this case, it is effective to choose the strategy that wood from line thinning is for total use of wood biomass.E4KJ00006290581論文Articl
The Governance of Local Resources Circulation Regime : Analysis from the Standpoint of "Commons Theory"
Get PDF本研究は,「持続可能な社会」構築の鍵とされてきた社会関係論に関する一試論であり,互酬的な関係("共同体の原理")をベースとした地域資源循環レジームの成立条件をコモンズ論の見地から解明することを目的としている。現在,わが国では,各地で行政・企業・市民等の相互連携による地域資源循環システムの構築に力が注がれているが,先行研究において,その成立条件として指摘されているのはアクター間の合意形成である。この点においては,慣習・慣例,コミュニティといったインフォーマルな部分の分析が欠かせず,地域資源循環レジームの統治に関しては,"共同体の原理"がキーワードとなる。そこで本研究においては,アクター間の合意形成過程における"共同体の原理"に着目し,コモンズ論の見地から地域資源循環レジームの統治について検討した。This study is an analysis of social relationship as a means to sustainable society construction. I analyzed from the "commons theory" of formation factors of local resources circulation regime by community. In Japan, the government, companies, and civic cooperation are encouraged to construct the local resources circulation regime. In a preceding study, it was pointed out that the main formation factor of the local resources circulation regime is consensus formation. However, it is also important to focus on informal regulation, such as "custom" or "community". The principle of community is necessary for the governance of local resources circulation regime.In this study, I focused on "the principle of community" in the consensus formation process between actors and discussed local resources circulation regime from the standpoint of "commons theory".E6KJ00006290779論文Articl
Emu for Bioindustry
Get PDFエミューは環境適応性に優れた走鳥類で，北海道・網走市では新規家禽として，そのオイル（機能性物質）生産を目的に飼育・増殖されている。しかし，本鳥に関する情報は内外とも少ないことから，筆者は新規産業鳥として，その生産向上に関わる事項について独自に調査してきた。本稿では，文献を参考にしながらその内容をまとめた。ペアリング後，交尾は早いペアーで14日目，遅いのは74日目で確認された。産卵期間は，11～翌年5月までの7ヶ月間であった。産卵数は2～3月に多く，全体の56.73％であった。雌・雄同比率繁殖群の産卵数（雌1羽当たりの産卵数が18.50個）は，10羽以上の集団および雌・雄異比率繁殖群（それぞれ雌1羽当たり6.55個と9.51個）に比べ有意に高かった（p＜0.01）。ペアリングでは，産卵数20個の個体が翌年に1個に激減した例，同一ペン内で，雌が同一雄とのペアリングを解消するためペンからの移動を試み事故死した3例，また2頭の雄と交尾した1例が観察された。雌には，同一雄とペアリングを継続するタイプと産卵後に雄を交換するタイプが存在すると推察され，飼育下では前者のタイプが多く認められた。受精率は，2009～2010年と2010～2011年で，それぞれ89.64％と86.14％で，孵化率はそれぞれ67.34％と64.64％であった。受精率は産卵数の増加に伴って高くなる傾向にあった。交尾は1～3月に集中し，その割合は80.23%であった。また，交尾時間帯は午前3～9時に集中し75%を占め，特に，午前5～9時の間に52.04%であった。交尾持続時間は22～74秒間が多く72.23%であった。最長時間は3分50秒 （230秒）であった。交尾回数はペアーによってバラツキが大きく10～59回の間に分布した。産卵数が多いペアーは交尾時間も長い傾向にあった。4～5歳齢（雌・雄）の平均体重は約40kgになるが，脂肪重量は雄（9.42±0.40kg）が雌（7.34±0.64kg）に比べ有意に高かった（p＜0.01）。体重（♂）が30～35kg区の脂肪重量は5.99±0.35kgで，50～55kg区では15.33±0.85kgで有意差が認められた（p＜0.01）。体重と脂肪重量間には強い正の相関（r=0.785）が認められた。雄の脂肪重量に関して，下半期が9.94±0.47kgで，上半期（7.75±0.64kg）に比べ有意に高い値であった（p＜0.01）。The emu is a ratite with marked environmental adaptability, bred in Abashiri City, Hokkaido mainly for oil (functional material) production. However, laying, fertility, and hatchability should be improved for mass breeding. Thus, in the present study, we investigated the relationship between pairing and laying to improve egg production. After pairing, mating was observed on day 14 at the earliest and on day 74 at the latest. The laying period was seven months between November and May of the following year. Egg production was highest in February and March at 25.79 and 30.94%, respectively. The relationship between pairing and laying demonstrated that egg production in breeding groups of equal female-to-male ratios (18.50 eggs per female) was significantly higher than those of population breeding groups and breeding groups with unequal female-to-male ratios (6.55 and 9.51 eggs per female, respectively) (p<0.001). The female-to-male ratio was altered in pairing, markedly decreasing the egg production from 20 to 1 the following year. For example, two females died as a result of an accident during transfer to a different pen, conducted to prevent pairing with the same male, while one female mated with two different males. Thus, some females continued to mate with the previous males, while the others mated with different males after laying. Fertility was 89.64 and 86.14% and hatchability was 67.34 and 64.64% in 2009-2010 and 2010-2011, respectively. The mating frequency peaked from January to March, accounting for 80.23% of the total. The mating time zone peaked from 3:00 to 9:00 a.m., accounting for 75%, but particularly from 5:00 to 9:00 a.m., accounting for 52.04%. The mating duration peaked at 22-74 seconds, accounting for 72.23%. The longest mating duration was 3 minutes and 50 seconds (230 seconds). The mating frequency varied among pairs, ranging from 10 to 59. Pairs with high egg production tended to show a longer mating duration. The mean body weight of four- and five-year-old emus was 40kg. The body fat weight of males (9.42±0.40 kg) was significantly larger than that of female emus (7.34±0.64kg) (p<0.01). There was a strong correlation between the body and fat weights (r=0.785). The fat weight of male emus shipped in the first and second periods were 7.75±0.64 and 9.94±0.47kg, respectively ; the weight of fat in the second period was significantly larger (p<0.01).E2P総説Revie
Effects of Salt Concentration and Pressure Intensity on Formation Mechanism and Microstructure of Pressure-Induced Gel of Actomyosin
Get PDF低温での加圧処理により形成したアクトミオシンゲルの形成機構を明らかにするため，アクトミオシン濃度20～30mg/g，KCl濃度0～0.6M，pH6.0の条件下で200～650MPaの加圧処理を行った。また，ゲルの形成に寄与するタンパク質間相互作用やゲルの微細構造についても検討を行った。その結果，アクトミオシンはKCl濃度0.2M，pH6.0に調整し，アクトミオシンの大半を構成するミオシンをフィラメントの状態とし，0℃で200MPa以上の加圧処理を行うことによりゲルを形成した。アクトミオシンゲルのゲル強度およびワークダン値は200～300MPaで増加し，300MPaで最も高い値を示したが，400MPa以降で減少した。また，ゲル形成に寄与するタンパク質間相互作用は非共有結合を主とし，300MPa以下はイオン結合が，400MPa以上では疎水性相互作用が主要な相互作用であった。ゲルの微細構造も300MPa以下と400MPa以上では形態が異なり，架橋部は太く，密な構造へ遷移した。これらのことから，加圧処理によりアクトミオシンは低塩濃度でゲルを形成し，300～400MPaの間でタンパク質の大きな高圧変性が起こり，ゲル形成に寄与するタンパク質間相互作用が変化することにより，ゲルの物理的特性が変化することが示唆された。In this study, the mechanism of pressure-induced gel formation of actomyosin at low temperature was clarified. Actomyosin has been high-pressure processed under processing conditions with 20～30mg/g proteins, 0～0.6M KCl and pH6.0 at up to 650MPa. In addition, protein-protein interaction to contribute to gel formation of actomyosin and gel microstructure were investigated. Actomyosin was adjusted in 0.2M KCl at pH6.0, and myosin formed to the filament which constitutes most of actomyosin. This actomyosin solution formed gel by high-pressure processing at 200MPa or more at 0℃. Gel strength and Work Done of actomyosin gel increased in 200～300MPa and showed the highest value in 300MPa, however decreased 400MPa or more. Furthermore, protein-protein interaction contributing to the gel formation non-covalent bonds was primary. In the main protein-protein interaction, 300MPa or less were ionic bond, 400MPa or more were hydrophobic interaction. Gels at 300MPa or less were different from microstructure at 400MPa or more, and the microstructure changed to dense structure with increasing pressure. These results show that actomyosin formed the filament gel in low salt concentration by high-pressure processing. In these pressure-induced actomyosin gels, protein-protein interactions were caused by high pressure denaturation in 300～400MPa, and the physical characteristic of the gel changed.E4P論文Articl
Effects of Emu Oil on Nitric Oxide Production of Macrophage
Get PDFマクロファージは，細菌感染やがん細胞の発生の際に活性化する細胞であり，一酸化窒素（NO）などの炎症性物質を産生し，生体を防御する働きをもつ。しかし，炎症性物質の過剰産生は，リウマチなど多くの疾患の原因となるため，これを抑える抗炎症物質が広く機能性食品や化粧品，医薬品として利用されている。本研究では，エミュー（Dromaius novaehollandiae）の皮下脂肪から得られるエミューオイルが，マクロファージによって産生されるNOに与える影響を調べた。マウス由来培養マクロファージ（RAW264.7）をリポポリサッカリド（LPS）で刺激すると，NOの産生量は6倍に増加した。一方，エミューオイルを添加した培養液で培養したRAW264.7では，この増加はエミューオイルの存在下で抑制された。また，RAW264.7をLPSで刺激するとNO合成酵素（NOS）の発現量が2倍に増加した。このNOSの発現量の増加は，エミューオイルで培養したRAW264.7では抑制された。したがって，エミューオイルはLPSによるマクロファージのNOS過剰発現を抑制し，NOの産生量を減少させることが明らかとなった。すなわち，エミューオイルには，過剰な炎症性物質の産生を抑制する効果があることが示唆された。Macrophage, which is the cells activated by bacterial infection and growth of cancer cells, produces inflammatory mediators such as nitric oxide (NO) and plays a role in protecting the body. But overproduction of the inflammatory mediators causes various diseases such as rheumatoid arthritis. Therefore, the compounds suppressing the overproduction of inflammatory mediators are widely applied to functional foods, cosmetics and pharmaceuticals. In this study, we examined the effects of emu oil, obtained from emu (Dromaius novaehollandiae), on the production of NO by macrophage. When a cultured cell line of mouse macrophage (RAW267.4) was stimulated by lipopolysaccharide (LPS), NO production was increased by 6-times. Addition of emu oil to the culture medium inhibited the LPS-induced NO production. A stimulation of RAW264.7 by LPS increased twice the expression level of NO synthase (NOS). Emu oil decreased the LPS-induced increase in NOS. These results suggest that emu oil reduced the LPS-induced NO production by inhibiting the expression of NOS in RAW264.7. It is likely that emu oil possesses the ability to reduce the production of anti-inflammatory mediators by macrophage.E4P短報Not
Effect of Different Tilling Depth and Sowing Styles on Lodging Tolerance of Rice under Direct Underground Sowing in Flooded Paddy Field
Get PDF水稲の湛水土壌中直播栽培において,播種様式(散播と条播)並びに耕耘深度(5cmと15cm)が耐倒伏性に及ぼす影響を圃場試験で検討した。耕耘深度15cm区(15cm区)の散播区と条播区の倒伏程度は同程度で,しかも耕耘深度5cm区(5cm区)の散播区と条播区より高かった。5cm区では条播区が低く,最も耐倒伏性が強かった。条播15cm区は,散播15cm区に比べて押し倒し抵抗値と引き抜き抵抗値は高かったが,地上部生育が旺盛であったため散播15cm区と同程度の倒伏を示した。5cm区は,生存葉鞘枚数,押し倒し抵抗値および引き抜き抵抗値から判断して,根の活性や根の物理的強度の向上が倒伏を軽減したものと推察された。しかし,散播5cm区が,条播5cm区よりやや倒伏程度が大きかったのは,株直下に分布する根量が少なかったことによるものと考えられた。The purpose of this study was to clarify the effects of tilling depth (i.e., 5cm and 15cm) and sowing styles (i.e., broadcast and row sowing) on the lodging tolerance of rice under direct underground sowing in flooded paddy field. Lodging degree of broadcast and row sowing at the 15cm tilling depth, were same level, but were higher than in broadcast and row sowing at the 5cm tilling depth. Lodging degree of row sowing at the 5cm tilling depth was lowest, namely, the lodging tolerance was most superior. At the 15cm tilling depth, the pushing resistance and the pulling resistance were higher in row sowing than in broadcast sowing, but the top growth in the row sowing was vigorous, therefore the lodging in the row and broadcast sowing were same level. In the 5cm tillimg depth, it was guessed that the elevation of root activity and strength has brought about the mitigation of lodging, as judged by the numbers of alive leaf sheath, pushing resistance and pulling resistance. But in the 5cm tilling depth, it was considered that the lodging tolerance in broadcast sowing was inferior, by reason that the roots of rice below the hill were scanty.E7KJ00004074143論文Articl
Factors affecting the seed germination and seedling establishment of baical skullcap (Scutellaria baicalensis Georgi)
Get PDFコガネバナの栽培に関する研究は極めて少なく,栽培技術は確立されているとは言い難い。本研究は,適切な播種時期決定のために,種子の発芽に及ぼす温度の影響を調査し,さらに,出芽・苗立ちに及ぼすマルチの効果について検討を加えたものである。得られた結果の要約は次の通りである。1.産地の異なる種子の発芽試験の結果,寒冷地で採種された種子の発芽が良好で,発芽が早かった。2.種子の生産環境として,25℃では総莢数に対して稔実莢数が極めて少なく,15℃の冷涼な温度環境下での種子生産効率が高いことが判明した。3.コガネバナ種子の発芽は,光環境によって制御される傾向が高く,暗条件下で発芽歩合および発芽勢が高く,平均発芽日数も短縮された。4.発芽に及ぼす温度の影響から,発芽適温は15～25℃で,特に最適発芽温度は20℃前後と考えられる。さらに,平均気温が15℃以上となる時期が播種時期決定の指標となることが示唆された。5.マルチは,土壌水分保持を保持し出芽並びに苗立ちに効果的であることが認められた。It must be said that investigation on the cultivation of baical skullcap(Scutellaria baicalensis) is very little and the cultivation technique has not yet been established. In order to ascertain the appropriate seeding time decision, this study was carried out to assess the effect of temperature on the germination of the seed, and the effect of rice straw mulch on the emergence of seedling was examined. Results observed were as follows. 1. As a result of the germination test of the seed in which the locality differs, high germination percentage was observed and high germination rate of the seed was collected in the cold region. 2. It was proven that the seed production efficiency was high under cool thermal environment(15℃)as a favorable production environment of the seed. 3. The germination of the baical skullcap seed was controlled by the light environment, and germination percentage and germination rate were high under the dark condition, while the average germination days were also shortened. 4. From this study on the effect of temperature on the germination, we can say the moderate germination temperature is 15～25℃, and especially the optimum germination temperature seems to be around 20℃. In addition, it was considered that the time in which the mean temperature becomes over 15℃ became an index to the seeding time decision. 5. Rice straw mulch retained the soil moisture maintenance, and it might be effective in emergence of seedling and its establishment.E1KJ00004074167論文Articl
Pattern of Ovarian Follicular Growth in Japanese Quail
Get PDFニホンウズラにおける卵胞成長パターンを明らかにしようとして,2色の脂溶性色素を添加した飼料を1日おきにウズラに与え,得られた卵より卵胞の急速成長日数と卵胞成長期間における卵黄の蓄積量を明らかにした。その結果,卵胞成長日数は6.06±0.06日であり,その日々の卵黄蓄積量のパターンは3つに分けることが出来た。急速成長日数が4および5日の場合は,排卵日の蓄積量が最大となり,急速成長日数が6日の場合は,排卵日の前日の蓄積量が最大となり,急速成長日数が7および8日の場合は,排卵の前々日の蓄積量が最大となることが明らかになった。Pattern of ovarian follicular growth in Japanese quail was determined by the number of colored rings of the yolk of eggs obtained after daily feeding with two kinds of dye alternatively at the same time of each day. The length of the rapid growth was 6.06±0.06 days. Pattern of ovarian follicular growth was classified by three patterns. 1) In the case of rapid growth period of 4 and 5 days : Daily yolk increment reached the peak on the day of ovulation. 2) In the case of rapid growth period of 6 days : Daily yolk increment reached the peak at 1 day before the day of ovulation and then decreased. 3) In the case of rapid growth period of 7 and 8 days : Daily yolk increment reached the peak at 2 days before the day of ovulation and then decreased.E9KJ00004074186論文Short Communicatio
Effect of gonadotropin-releasing hormone administration during artificial insemination on the pregnancy rates in cattle
Get PDF一般畜産農家,公共牧場および本学富士畜産農場で飼育されている雌牛418頭に人工授精と同時に性腺刺激ホルモン放出ホルモン(GnRH,ブセレリン)を6,10および20μgを投与し,無処置対照群のそれと受胎率について比較した。また,本剤の投与効果を判定するために血漿中プロジェステロン濃度を測定し,黄体機能への影響についても検討した。その結果,ブセレリン6,10および20μg投与のいずれの群においても受胎率は対照群のそれよりも7.6～9.2%と高い成績が得られた。次いで,空胎期間の短い区(120日未満)と長い区(120日以上)に分けて検討したところ,空胎期間の長短に関係なく受胎率は投与群の方が対照群よりも高い傾向を示した。さらに,投与回数を1回と2回に分けたところ,1回目の投与での受胎率は,各投与群と対照群の間に有意差はなかったが,2回目の投与では投与群の受胎率は対照群よりも16.4～47.6%改善され,特に10μg投与群での受胎率は85.7%で対照群および6μg投与群よりも有意(P<0.05)に高いことが認められた。従って,受胎しにくい牛に対するブセレリン投与の効果が顕著に現れた。Gonadotropin-releasing hormone (GnRH, buserelin) was administered to 418 head of cattle bred by a general stock- raising farmer at a public pasture and here at the Fuji Zootechnical station, simultaneously during artificial insemination at doses of 6, 10 and 20μg respectively. Pregnancy rates for this group and for a non-treated control population were then compared. Blood progesterone concentration was also measured in order to determine the effect of this treatment. The effect on the luteal function was also examined. For buserelin, results were of 6μg and 10μg doses. Pregnancy rates for both groups with administered doses of 20μg resulted in a high 7.6～9.2%. The pregnancy rate for the buserelin-administered group was higher than that of the control population regardless of the merits and demerits during the non-pregnant period when they were examined. Subsequently, it was divided into the short division (less than 120) of a non-pregnant condition period, and the long division (120 or more) and investigated. In addition, there was no significant effect on the pregnancy rate following the first administration in each treated group and control population, when the administration frequency was divided into 1 and 2 times. During the second administration, the pregnancy rate of the treated group improved to 16.4～47.6% more than the control population and at a specially notable 85.7% pregnancy rate in the 10μg-dose administered group control population. It might be significantly higher (P<0.05) than the 6μg-dose administered group. Therefore, it is difficult to accurately demonstrate the effect of buserelin treatment on cattle pregnancy rates.E5KJ00004074191論文Articl