張伸彰 李錦足 林旻蓉 許晉賓 李世昌 涂海南 吳明哲 張秀鑾
DOMINANCE AND RECESSIVE INHERITANCE ON COAT
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.