Title: Estimates of Repeatability and Heritability of Egg Number in Sasso Hens in a Tropical Environment Abstract:

Abstract:

Estimates of Repeatability and Heritability of Egg Number in Sasso Hens in a Tropical Environment

The aim of this study was to derive variance components, and hence, estimate repeatability and heritability of weekly egg production in Sasso hens. The birds, each with an identification number, were randomly selected and kept in individual battery cages which permitted open ventilation. Egg production records of thirty eight (out of the initial fifty four stocked) Sasso birds with consistency in lay from week 31 to week 38 of age were utilized for subsequent analyses. The effect of age (week) on egg production was determined using one-way analysis of variance (ANOVA) procedure. Means were separated using Duncan’s Multiple Range Test (DMRT) at 95% confidence interval. The components of variance were estimated using the PROC VARCOMP option of restricted maximum likelihood (REML) method of the General Linear Model (GLM) procedure to generate repeatability and heritability coefficients. The mean egg number per week was 3.51 with coefficient of variation of 19.0-23.4%. Egg production appeared to increase with age which was significant (P<0.05) from week 37-38. The variance component based on combined ages of the birds was 0.049 while that of the residual was 0.551. Repeatability estimate (R ± S.E.) was low (0.082 ± 0.011). However, the estimate of heritability (h2S ± S.E.) for egg number in the current population was moderate (0.326 ± 0.011). Based on the heritability coefficient, elite birds with the best average performance for week 31-38 of age could be selected as parents to produce offspring with optimal egg production.

Biography:

llan Chet is a full Professor, Vice Dean for Research at the George S Wise Faculty of Life Sciences, Tel-Aviv University, Israel. He received in 1992 a PhD in Molecular Biology from the Hebrew University, Israel and was a Post-doc 1992-1995 at NCI, NIH. He joined Tel-Aviv University as a tenure-track assistant professor in 1995 and is a full professor since 2008. He is an expert in the fields of antibody engineering, drug discovery and drug delivery with over the 20 years of being active in these fields, 92 peer reviewed articles and 11 patents.