福岡県農業総合試験場研究報告22(2003) pp 107 - 111
イタリアンライグラス新品種‘シワスアオバ’の生育時期別飼料成分含量
藤吉弘子・棟加登きみ子・井上信明
（畜産研究所）
イタリアンライグラス新品種‘シワスアオバ’の飼料特性について，生育時期別に飼料成分含量の分析を行い ‘タチワセ’，‘アキアオバ’と比較検討した。
‘シワスアオバ’は‘タチワセ’や‘アキアオバ’に比べ，次のような特徴がある。
１ 1番草出穂期の粗蛋白質（CP）含量は多く，総繊維（OCW）含量は少ない。
２ 伸長期から開花期まで，高消化性繊維含量/総繊維含量（Oa/OCW）が高く，繊維の消化性が高い。
３ 出穂期に低消化性繊維（Ob）含量が少なく，リグニンを多く含む茎部割合が少ないため，可消化養分総量（TDN）と相関の高い人工乾物消化率（IVDMD）が 15%から20%高い。
４ 2番草の飼料成分含量では，‘シワスアオバ’と‘タチワセ’，‘アキアオバ’に顕著な差がない。
５ 1番草は従来から栽培されているイタリアンライグラスと比較して，粗蛋白質含量が高く，総繊維含量が低いため，高い消化性を示す。
以上のことから，‘シワスアオバ’はイタリアンライグラスの他の品種に比べて著しく成分が異なり，飼料成分表の数値を利用できないので，給与設計する際にはフォーレージテスト等を活用して正確に飼料成分を把握する必要がある。
[キ−ワ−ド：イタリアンライグラス，シワスアオバ，飼料特性，生育時期]
Feed Characteristic of the New Italian Ryegrass Cultiver 'Shiwasuaoba' Whitch was Examined from the Feed Composition Content According to Growth Stage. Hiroko FUJIYOSHI, Kimiko MUNEKADO, and Nobuaki INOUE (Fukuoka Agric. Res. Cent., Chikushino, Fukuoka 818-8549, Japan) Bull. Fukuoka Agric. Res. Cent., 22: 107 - 111 (2003)
The feed composition content of the new Italian ryegrass Cultiver 'Shiwasuaoba' according to growth stages and feed characteristics was analyzed and compared with 'Tatiwase' and 'Akiaoba'.
1 In the first cut grass in the heading stage, 'Shiwasuaoba' contains more crude protein (CP) and less organic cell wall (OCW) than 'Tatiwase' or ' Akiaoba'.
2 From the elongation stage to the blossom stage ,the high digestible fiber / organic cell wall content (Oa/OCW), which serves as an index for measuring digestibility is high.
3 During the heading stage, low digestible fiber (Ob) content and stem part content rich in lignin are low. This resulted in higher in vitro dry matter digestibility (IVDMD) by 15 to 20 points compared with the other two cultivers, which shows a high correlation with the possible digestive nourishment gross weight (TDN)
4 The first cut grass of 'Shiwasuaoba' is characterized its fiber ingredient in terms of feed composition.
5 However, the second cut grass of 'Shiwasuaoba' did not show any conspicuous difference from that of 'Shiwasuaoba' and 'Tatiwase' in the feed composition content as in the first cut grass 'Shiwasuaoba' feed ingredient content.
The above findings established that the ingredient content of 'Shiwasuaoba' differs significantly from that of 'Tatiwase' and 'Akiaoba', so that the feed composition table values are not applicable. In this context, when designing 'Shiwasuaoba' for rumination livestock forage test must be conducted to correctly grasp the feed composition.
[ Key word : Italian ryegrass new cultiver 'Shiwasuaoba', feed characteristics, growth stage ]