Nestor K E, Anderson J W, Velleman S G
Department of Animal Sciences, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio 44691, USA.
Poult Sci. 2005 Sep;84(9):1341-6. doi: 10.1093/ps/84.9.1341.
An experimental line (F) selected over 34 generations for increased 16-wk BW was reciprocally crossed with a primary breeding sire line (C) from a large international turkey breeder to study the inheritance of growth-related traits measured on live birds. All genetic groups were grown intermingled in confinement with sexes reared in different houses. The traits measured included BW at 8, 16, and 20 wk of age and shank length, shank width, shank depth, breast width, and walking ability scores at 16 wk of age. Walking ability was rated from 1 to 5 with 1 representing birds with no leg defects and no difficulty walking and 5 indicating birds with extreme lateral deviations of the legs and great difficulty walking. Ratings of 2, 3, and 4 represented intermediate values. The F line had a different growth pattern than the C line with the F line being larger than the C line at 8 wk of age, but the reverse was true at 16 and 20 wk of age. The difference in BW between the C and F lines increased from 16 to 20 wk of age. The C line had wider breasts than the F line at 16 wk of age. The F line had longer shanks than the C line. Shank width was larger in the C line than the F line for females but not males. No line difference in shank depth was observed. Walking ability scores at 16 wk of age were lower (better) in the C line than in the F line for males but not females. Significant heterosis in BW of the crosses of the F and C lines was observed at all ages in males (range = 3.3 to 5.6%) and only at 8 wk of age in females (3.6%). These results were similar to an earlier study in which the F line was crossed with a primary-breeding sire line from 2 other international turkey breeders. No significant heterosis in the crosses of the C and F line was observed for breast width and shank measurements. Heterosis was significant for walking ability scores of females (-3.0%) but not males. Reciprocal effects, a measure of sex linkage and maternal influences, were noted only for shank length and the direction of the difference was not the same in the 2 sexes.
选择一个经过34代选育、16周龄体重增加的实验品系（F）与一家大型国际火鸡育种公司的一个原种父系品系（C）进行正反交，以研究活体火鸡生长相关性状的遗传情况。所有遗传群体在密闭环境中混养，雌雄分舍饲养。测量的性状包括8周龄、16周龄和20周龄时的体重，以及16周龄时的胫长、胫宽、胫深、胸宽和行走能力得分。行走能力从1到5评分，1表示腿部无缺陷且行走无困难的火鸡，5表示腿部有严重外侧偏差且行走困难的火鸡。2、3和4分表示中间值。F品系的生长模式与C品系不同，F品系在8周龄时比C品系大，但在16周龄和20周龄时情况相反。C品系和F品系之间的体重差异从16周龄到20周龄逐渐增加。在16周龄时，C品系的胸部比F品系宽。F品系的胫比C品系长。雌性火鸡中，C品系的胫宽比F品系大，雄性则不然。未观察到胫深的品系差异。在16周龄时，雄性火鸡中C品系的行走能力得分低于（即更好）F品系，雌性则不然。在所有年龄的雄性中（范围为3.3%至5.6%）以及仅在8周龄的雌性中（3.6%），观察到F品系和C品系杂交后代的体重存在显著杂种优势。这些结果与早期一项研究相似，在该研究中F品系与另外两家国际火鸡育种公司的原种父系品系进行了杂交。对于胸宽和胫部测量，未观察到C品系和F品系杂交后代有显著杂种优势。杂种优势在雌性行走能力得分方面显著（-3.0%），在雄性中则不然。仅在胫长方面注意到正反交效应，这是衡量性连锁和母体影响的指标，且两性差异的方向不同。
