| 释义 |
▪ I. ˈoutcross, n.
[out- 6.]
A cross with an unrelated breed or race. Also attrib.
1890J. M. Tracy in Upland Shooting 398 It may happen that the outcross has been to some extremely prepotent breed. 1900Trans. Highl. & Agric. Soc. 164 [He] rarely sought an outcross for his broadly founded herd. 1918Genetics III. 475 When double-throwing Matthiola is used as egg parent in an outcross to ordinary singles, half the offspring receive a factor for doubleness. 1949R. B. Kelley Sheep Dogs (ed. 3) iv. 62 It is not necessary to purchase such out-cross dogs. 1971Farmer & Stockbreeder 16 Feb. 49/1 An unplanned out-cross with an unknown wheat took place and this brought much improved fertility. 1975Times 25 Aug. 8/5 Original out⁓crosses were Northumberland-bred Scottish Blackfaces. 1977Horse & Hound 14 Jan. 15/3 Malacate stands out as a potential outcross for the majority of high-class European mares.
▪ II. outcross, v.
(stress even)
[f. the n.]
trans. To cross (an animal or plant) with one not closely related. Also absol.
1918Genetics III. 437 Each [beaded fly] was outcrossed separately to a fly from some non-beaded stock. 1931E. B. Ford Mendelism & Evolution ii. 40 If the now highly inbred stock be outcrossed to ordinary wild-type flies, it is found that the extracted recessives..have returned to the original condition. 1949R. B. Kelley Sheep Dogs (ed. 3) iv. 62 It will be necessary continually to out-cross by introducing dogs unrelated to the favoured animal, so that close-breeding is avoided. |