GENETIC TRENDS OF PROLIFICACY AND LITTER SIZE IN ROMNEY MARSH SHEEP

被引：4

作者：

BHUIYAN, AKFH ^{[1
]}

CURRAN, MK ^{[1
]}

机构：

[1] UNIV LONDON WYE COLL,ASHFORD TN25 5AH,KENT,ENGLAND

来源：

SMALL RUMINANT RESEARCH | 1993年 / 12卷 / 03期

关键词：

ROMNEY SHEEP; PROLIFICACY; LITTER SIZE; GENETIC TREND; BREEDING VALUE ESTIMATION;

D O I：

10.1016/0921-4488(93)90066-Q

中图分类号：

S8 [畜牧、动物医学、狩猎、蚕、蜂];

学科分类号：

0905 ;

摘要：

Genetic trends were estimated by mixed model procedure. Records were on 588 and 548 selected ewes, respectively, representing 7 years of birth groups from 1980 to 1986. Traits were evaluated independently. The analyses were within ewe ages (2, 3 and 4 years). Regressions of overall average breeding values on year of births increased (0.0014) for prolificacy (P<0.05) and rate of increase was higher for prolificacy than litter size, possibly because of direct selection pressure on prolificacy. The study indicated the effectiveness of selection for prolificacy in the Romney Marsh sheep. It is also indicative that simple procedure for solving mixed model equations can well be used for the estimation of genetic trends of reproductive traits in sheep.

引用

页码：315 / 320

页数：6

共 23 条

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