著者
スウィト アノタイシンタウェー チャイヤワン ワッタナチャント 野村 こう 大石 孝雄 天野 卓 Anothaisinthawee Suwit Chaiyawan Wattanachant Koh Nomura Takao Oishi Takashi Amano
出版者
東京農業大学
雑誌
東京農業大学農学集報 (ISSN:03759202)
巻号頁・発行日
vol.57, no.1, pp.63-70,

濃厚飼料給与量を体重の1パーセントとした給餌条件下で飼育したタイ産肉用ヤギ3集団の屠体成績を得ることを本研究の目的とした。南部タイ在来種,2元交雑(50%アングロヌビアン種×50%在来種),3元交雑(50%ボアー種×25%アングロヌビアン種×25%在来種)から健康な1歳雄18頭を無作為に選び,24時間絶食後,屠殺した。3元交雑は2元交雑および在来種に比べ,屠殺前生体重,枝肉重量,枝肉長の値が有意(P<0.01)に大きかった。枝肉歩留は50.20~54.28%で,3元交雑が有意(P<0.01)に低かった。3元交雑のロース心面積は,2元交雑や在来種に比して有意(P<0.01)に大きかった(それぞれ16.97,11.19,8.13cm^2)。屠体の物理学的特性,肉の化学組成と微細構造は,骨と肉の比率を除いて3集団に差はなかった。在来種の骨量は他集団に比べ有意(P<0.01)に低く,筋肉─骨比はほかの2集団に比べて有意(P<0.01)に高かった。また可食肉(筋肉+脂肪)─骨比も有意(P<0.05)に高かった。肉のタンパク含量は3元交雑(22.4%)が有意(P<0.05)に高く,脂肪も同様(P<0.01)であった。肉の剪断力価と肉色は集団により有意(P<0.05)に異なった。胸最長筋の剪断力価は大腿二頭筋や上腕三頭筋より低く(P<0.05),国際標準照度値による肉色測定では大腿二頭筋と上腕三頭筋の肉色は胸最長筋よりも暗かった(P<0.05)。The objective of this study was to assess the carcass characteristics of three genotypes of meat goats in Thailand, kept in a semi-intensive system with concentrated feed at 1% of body weight. Eighteen healthy male yearlings, including Southern Thai native, two-way crosses (50% Anglo-Nubian ×50% native) and three-way crosses (50% Boer ×25% Anglo-Nubian ×25% native) goats were randomly selected and slaughtered after being starved for 24 h. Three-way crosses had greater (P<0.01) fasted live weight, carcass weight and carcass length than two-way crosses and native goats in the same environment. The dressing percentage (based on empty body weight) ranged from 50.20% to 54.28%, with highly significant differences between genotypes. Three-way crosses had greater (P<0.01) loin eye area than two-way crosses and native goats (16.97, 11.19, and 8.13cm^2, respectively). Physical properties, chemical composition of meat, and muscle microstructure of the three genotypes were determined. There were no differences in physical properties between genotypes, except for bone percentage. Native goats had lower (P<0.01) bone content than two-way and three-way crosses. The muscle-bone ratio was higher (P<0.01) in native goats than in other goats, even using the criterion of edible meat (muscle+fat-bone ratio, P<0.05). The protein percentage of muscles was significantly higher in three-way crosses (22.4%) than in two-way crosses and native goats (P<0.05). The fat percentage of three-way crosses was higher (P<0.01) than that of two-way crosses and native goats. Genotype had a significant (P<0.05) influence on meat quality in regard to shear force and lightness. The longissimus dorsi had a lower shear force value than the biceps femoris and triceps brachii (P<0.05). The International Commission on Illumination system values for the biceps femoris and triceps brachii were lower (P<0.05) than those for the longissimus dorsi.