
%0 Journal Article
%A Sheldon, BL 
%T Genetic parameters associated with characters effecting egg production in the domestic fowl. I. Heritability of total egg production during the pullet year
%J Australian Journal of Agricultural Research
%D 1956/12/01
%V 7
%N 6
%P 625-629
%K 
%R https://doi.org/10.1071/AR9560625
%U https://www.publish.csiro.au/paper/AR9560625 
%X Egg production records of White Leghorn pullets hatched a t the Poultry Research Centre, Werribee, Vic., during 1947 to 1950 inclusive have been analysed both on a hen-housed (Production Index) and a survivor basis. Estimates of heritability were obtained by two methods: (1) by the analysis of components of variance between families of full sibs and half-sibs; (2) by estimating the intra-sire regression of the mean performance of offspring on dam's performance. Heritability, in the narrow sense, of Production Index during the pullet year is shown to be 23-30 per cent. with a reasonably low standard error, while heritability of survivors' production is slightly lower but not significantly so. Possible reasons are advanced for the low estimates of heritability of survivors' production. 
