絲羽烏骨雞外表特徵之遺傳模式：I. 羽色、爪型與腳脛毛

鍾秀枝 張秀鑾 吳明哲 黃祥吉 林德育

行政院農業委員會畜產試驗所

絲羽烏骨雞為東方國家的地方雞種，有核桃冠、纓頭、藍耳、鬍鬚、白色絲羽、五爪、腳脛毛、烏皮、烏肉與烏骨等十大特徵。本試驗為探討絲羽烏骨雞外表特徵之遺傳模式，應用10隻絲羽烏骨母雞為母本，畜試土雞近親品系公雞3隻為父本，於夏季採人工授精方式生產雜交後裔。計收集101個種蛋，孵育7天的受精率為80.2% (81/101)；隨後計孵出67隻雜交雞，孵化率為82.7%(67/81)。雛雞於四週齡時，已可分辨羽色、爪型、有無腳脛毛與烏皮等外表特徵。雜交雞的羽毛顏色均為父本土雞之黃褐色，腳脛顏色與皮膚顏色皆為黑色，結果顯示絲羽烏骨雞之白色絲羽為隱性，近親土雞之黃褐色羽毛為顯性，絲羽烏骨雞之黑色皮膚為顯性。雜交雞的左右腳爪型有4/4、4/5、5/4、5/5和6/6者，分別佔31.3、9.0、9.0、49.2%和1.5%。本試驗採用的10隻絲羽烏骨母雞，有4隻沒有腳脛毛，其雜交後裔均不具腳脛毛；而有6隻是具有腳脛毛，但其雜交後裔中僅有44.1% (15/34)具腳脛毛。當左右腳脛毛(F)和爪型一起評估時，發現有17.6%為4F/4F、29.4%為4－/4－、17.6%為5F/5F、17.6%為5－/5－、5.9%為5F/4－、3.0%為4F/5F、以及5.9%為4－/5－和3.0%為6－/6－。結果顯示：雜交雞左右腳的爪數並不一定相同，腳脛毛與爪數係獨立分離表現。

關鍵語：雞、雜交、外表特徵。

INHERITANCE MODE OF CHARACTERIC FEATURES IN WHITE SILKIER
CHICKEN: I. FEATHER COLOR, NUMBER OF TOES AND FEATHERS ON SHANKS

H. C. Chung, H. L. Chang, M. C. Wu, H. C. Huang and D. Y. Lin

Taiwan Livestock Research Institute, Council of Agriculture

White Silkier is one of the oriental local chicken with 10 characteristic features, such as the walnut comb, the presence of crest, the blue ears, the bearded, the white silky feather, the presence of five toes on each foot, the feathered shanks, the black skin and the black muscle as well as the black bone. The objective of the experiment was to study the inheritance mode of characteristic features in white silkier chicken. Birds used in the study included 10 white silkier hens and 3 TLRI inbred cocks as dams and sires, respectively. Artificial insemination technique was used to produce cross progeny in summer. There were 101 fertilized eggs collected and hatched with 80.2% (81/101) of hatchability at day 7, and resulted 67 chick crosses produced with 82.7%(67/81) of hatchability during days 7 and 21. Feather color, pattern in number of toes, feathers on shanks and black skin of chicks can be identified at 4 weeks of age. All crossed chicks showed black shanks and skin with yellowish brown feather as sires', which indicated white silkier feather being recessive to yellowish brown feather of inbred chicken but black skin of White Silkier being dominant to yellow skin of native chicken. The patterns of number of toes in left and right shanks were 4/4, 4/5, 5/4, 5/5 and 6/6 which accounted for 31.3, 9.0, 9.0, 49.2% and 1.5%, respectively, in F1 cross. In addition, 4 of 10 hens used in the study had no feathers on shanks and thus none of the corresponding F1 chicks was observed with feathered shanks. However, 44.1% (15/34) of progeny from 6 hens with feathered shanks had feathers on shanks. When feathers on shanks (F/－) and number of toes (4, 5 or 6 ) were jointly evaluated, there were 17.6, 29.4, 17.6, 17.6, 5.9, 3.0, 5.9 and 3.0% of F1 progeny with 4F/4F, 4－/4－, 5F/5F, 5－/5－, 5F/4－, 4F/5F, 4－/5－ and 6－/6－, respectively. Results indicated that number of toes in left and right sides might not be symmetric for F1 progeny. Also, the inheritance of feathers on shanks and pattern in number of toes were segregated independently.

Key Words: Chicken, Crosses, Characteristic features.