枝分かれ鎖のアミノ酸は,卵母鶏の腸肝軸媒介によるアンモニア過剰産生を誘発する
Huafeng Jian1,2, Mengru Xu1, Fang Liu1
1Zhejiang Key Laboratory of Nutrition and Breeding for High-Quality Animal Products, Key Laboratory for Animal Molecular Nutrition of Ministry of Education, Institute of Feed Science, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
Animal nutrition (Zhongguo xu mu shou yi xue hui)
|September 2, 2025
まとめ
産卵鶏の栄養補給による分枝アミノ酸 (BCAA) 摂取は,アンモニアを産生する腸内細菌を増加させ,高アンモニア血症を引き起こし,卵の産卵を減少させた. これは,家禽の食事におけるBCAAの過剰供給の可能性を強調しています.
科学分野:
- 動物の栄養
- 腸内微生物群の研究
- 鶏肉科学
背景:
- 分岐鎖アミノ酸 (BCAA) の代謝における腸内微生物群の役割は確立されているが,食事によるBCAA補給が腸内微生物群と宿主代謝に与える影響は不明である.
- これらの相互作用を理解することは 鶏の生産と健康を最適化するために不可欠です
研究 の 目的:
- 産卵鶏の生産性,卵の質,腸内微生物の構成,宿主の代謝に対するBCAA補給の影響を調査する.
- BCAAが誘発した腸内の変化とその結果の背後にあるメカニズムを解明する.
主な方法:
- 180羽の産卵鶏は,BCAAの異なる組み合わせ (ルシン,イソルシン,または3つとも) を補足した基礎栄養を8週間摂取した.
- 評価された生産性,卵の質,血清の生化学,肝臓の遺伝子発現 (トランスクリプトミクス),腸内微生物群の組成 (16S rRNAシーケンシング),腸内代謝学.
主要な成果:
- アイソルエウシンとBCAAを多く摂取すると 卵の質量と産卵率が低下した.
- BCAAを多く摂取すると 卵黄の色が上がるだけでなく 血清のアンモニア濃度も上昇し,アンモニアを産生するバクテリアが増殖する.
- 肝臓の尿素サイクル遺伝子発現は低下し,SCAP発現は上昇し,アンモニアの解毒を阻害し,高アンモニア血症を引き起こした.
結論:
- 特に高量のBCAAを摂取すると,アンモニアを産生する微生物群が増加し,アンモニアの過剰摂取と産卵能力が低下します.
- 肝臓の尿素循環は過剰なアンモニアを排毒する能力が不足し,SCAPのアップレギュレーションにより悪化し,健康への悪影響をもたらします.
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