梅山豬與杜洛克豬雜交後裔之毛色及耳朵顯隱性遺傳

張伸彰 李錦足 林旻蓉 許晉賓 李世昌 涂海南 吳明哲 張秀鑾

行政院農業委員會畜產試驗所

豬毛色及耳朵下垂之遺傳基因,常被認為是顯隱性遺傳,亦曾被認為與豬肉的風味有關。耳下垂的黑色梅山豬(M)與立耳的紅棕色杜洛克豬(D)之雜交後裔於出生時紀錄其毛色,毛色區分為黑色(B)、黑金斑(L)、紅金斑(Q)及紅色(R)等四種。M與D正反雜交之雜交一代(F1)仔豬毛色為L、B、R與Q依序有50.6、47.3、2.15與0.0%。F1交配所產生雜交二代(F2)之仔豬毛色為L、B、R與Q分別為18.7、57.0、11.3及13.0%。F1母豬回交D公豬所產生仔豬毛色為L、B、R與Q分別為30.9、27.4、27.1及14.6%。仔豬於70日齡紀錄其站立時耳朵性狀,依據前傾下垂的耳尖所在位置,而區分為五種耳朵:短立耳(耳尖未蓋眼)、短垂耳(耳尖未超過眼與鼻吻端之中線)、中垂耳(耳尖至眼與鼻吻端之中線)、垂耳(耳尖超過眼與鼻吻端之中線)與長垂耳(耳尖與鼻吻齊或超過)。F1仔豬耳朵為短垂耳、中垂耳與垂耳分別為16.3、64.6及19.1%,F2仔豬耳朵為短垂耳、中垂耳與垂耳分別為30.0、40.0及20.0%。F1仔豬與F2仔豬的毛色頻率符合矯正卡方分布所進行遺傳分離適合度測定,其估值χ2估值與理論值相符;但F1母豬回交D公豬所產仔豬,則出現L與B比率遠較正常分離比率高。F2仔豬並未有短立耳和長垂耳,顯示耳朵大小並非單一顯隱性基因所控制。

關鍵語:梅山豬、杜洛克豬、膚色、耳朵大小。

 

DOMINANCE AND RECESSIVE INHERITANCE ON COAT COLOR AND
EAR SIZE OF HYBRID PIGLETS BETWEEN MEISHAN AND DUROC BREEDS

S. C. Chang, F. C. Lee, M. J. Lin, C. B. Hsu, S. C. Lee, H. N. Twu, M. C. Wu and H. L. Chang

Taiwan Livestock Research Institute, Council of Agriculture

Generally, lop ear is dominant and prick recessive. Uniform black coat color is dominant and uniform red is recessive. Quite apart from personal preferences and the desire to use color and ear as the meat badge of taste quality. Coat color and ear size traits of hybrid piglets between Meishan (M) and Duroc (D) breeds were recorded at birth. M has black coat color and D has red coat color. M has lop ears and D has prick ears. Coat color was classified into black (B), golden longitudinal stripes of black (L), golden longitudinal stripes of red (Q) and red(R). Frequency of L, B, R and Q coat color in hybrid piglets (F1) between M and D were 50.6, 47.3, 2.15 and 0.0%, respectively. The coat color of F2 piglets with L, B, R and Q patterns were 18.7, 57.0, 11.3 and 13.0%, respectively. In analysis of piglets produced from F1 sows and backcrossing with D boars, L, B, R and Q coat color were 30.9, 27.4, 27.1 and 14.6%, respectively. At 70 days of age, piglets were examined on their ears while standing. The lop-eared pig had a larger ear in size than those of prick-eared pigs. Therefore, according the position of the tip of ear short near to the eye or long enough to the snout, five types were designated: short-prick ear (short near to the eye), short-lop ear (between eye and snout but near to eye), medium-lop ear (between eye and snout but in half way), lop ear (between eye and snout but near to snout), and long-lop ear (over the snout). F1 piglets with short-lop, medium-lop or lop ear were 16.3, 64.6 and 19.1%, respectively. F2 piglets with short-lop, medium-lop or lop ear were 30.0, 40.0 and 20.0%, respectively. The values of adjusted χ2 test on goodness of fit for Mendelian segregation of F1 and F2 hybrid piglets between M and D. The segregation percentage of coat color in piglets from F1 sow sired by D boars was greater than control did. There were no short-prick or long-lop eared piglets in F2 generation, which indicated that the ear size was not inherited as a single dominant gene.

Key Words: Pig, Coat color, Ear.