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dc.contributor.authorRendel, John Martin
dc.date.accessioned2014-04-16T23:21:43Z
dc.date.available2014-04-16T23:21:43Z
dc.date.issued1985
dc.identifier.urihttp://hdl.handle.net/10179/5252
dc.description.abstractPerforrnance records on 219, 000 ewes and 231,000 lambs from 48 Coopworth flocks were obtained from Sheeplan files. The flocks were divided into 5 climatologically similar regions: Northland; north of Taupo excluding Northland; reminder of the North Island; the South Island north of Palmerston, excluding the West Coast; the South Island south of Palmerston. Flock records were edited in an effort to remove recording errors. Within-flock environmental estimates were obtained using ordinary least squares procedures for continuous characters or iterative weighted least squares for binomial characters. The within-flock estimetes were weighted by the inverse of their standard errorr's and weighted means of the regional and national fixed effects were obtained. Paternal half-sib heritability estimates were obtained for each flock. There were few significant differences in the environmental estimates between regions. The traits examined (with the average of the heritability estimates) were: weaning weight (0.17); ram autumn liveweight (0.24); ewe autumn liveweight (0.26); ram winter liveweight (0.26); ewe winter liveweight (0.31); ram spring liveweight (0.29); ewe spring liveweight (0.34); ram hogget fleece weight (0.29); ewe hogget fleece weight (0.33); survival of all lambs (0.04); single lamb survival (0.05) and multiple lamb survival (0.05); proportion of a ewe's lambs surviving (0.04); number of lambs born to a ewe present at mating (0.12); number of lambs weaned per ewe lambing (0.07); given a ewe lambed, did she bear multiples (0.14); weight of lamb weaned per ewe rearing lambs (0.10). Selection and non-random mating may have biased the estimates.en
dc.language.isoenen
dc.publisherMassey Universityen_US
dc.rightsThe Authoren_US
dc.subjectCoopworth sheepen
dc.subjectSheep flock recordsen
dc.subjectSheep breedingen
dc.titleA study of regional differences in within-flock sources of variation in Sheeplan records of production traits for Coopworth sheep : a thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science at Massey Universityen
dc.typeThesisen
thesis.degree.grantorMassey Universityen
thesis.degree.levelMastersen
thesis.degree.nameMaster of Agricultural Science (M.Agr.Sc.)en


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