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Estimates of heritability for 9 litter traits were derived from data on 38 000 Large White and 35 000 Landrace litters by daughter-dam regression (parities 1 to 5) and by a three-level nested half-sib analysis (parities 1 to 3). The regression and half-sib heritability estimates were similar and overall the estimates were quite low, averaging 7% across traits and breeds. This is in general agreement with estimates from two other large-scale European analyses of field data. Some other reports, including lesser experimental material, show rather higher heritability values.
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Strang et al. (1979) studied this question.
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