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Accounting for subpopulations in prediction of the proportion of lean meat of pig carcasses

Published online by Cambridge University Press:  02 September 2010

B. Engel  and
P. Walstra
B. Engel
Affiliation:
Agricultural Mathematics Group, GLW-DLO, PO Box 100, 6700 AC Wageningen, The Netherlands
P. Walstra
Affiliation:
Research Institute for Animal Production‘Schoonoord’, IVO-DLO, PO Box 501, 3700 AM Zeist, The Netherlands
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Abstract

In a dissection trial in The Netherlands two subpopulations were distinguished: gilts and castrated males. The sampling scheme, which emphasizes extreme values for the proportion of lean meat in the carcass, was followed for the two sexes separately, to ensure sufficient accuracy for a comparison between them. Significant differences between the prediction formulae for the lean meat proportion for the two sexes were found. Since it is not possible to use separate prediction formulae for the sexes in Dutch slaughterhouses, the formulae had to be combined into one overall prediction formula. In this paper it is shown how the separate prediction formulae for the sexes may be combined, utilizing additional data, not involving dissection, which were easily collected on the slaughterline, at little extra cost. The method can be extended to cover any number of subpopulations. Two objectives can be achieved at the same time: subpopulations may be compared accurately on the basis of a stratified sample and from the results of the comparison an efficient, unbiased, overall prediction formula may be distilled.

Keywords

carcass compositioncastrated malesgiltspigsregression
Type
Research Article
Information
Animal Production , Volume 57 , Issue 1 , August 1993 , pp. 147 - 152
Copyright
Copyright © British Society of Animal Science 1993

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