Comparison of commercial and locally developed layers performance and egg size prediction using regression tree method

Abstract

The aim of this study is to compare the hen-day egg production (HDEP) (%), egg size (ES) (g), feed intake (FI) (g), bodyweight (BWT) (kg), body weight gain (BWTG) (g), feed conversion ratio (FCR), feed utilization (FU), and mortality of imported and local commercial egg layers from one to 20 wk of lay, as well as to predict their egg sizes. Two-thousand-six-hundred Hy-line Silver Brown commercial layers (imported) and 2,470 Boschveld indigenous commercial layers (local) were reared from d old to 44 wk of age and fed the same diet throughout. ANOVA was used to test their effects due to the strains, and the CHAID algorithm of regression tree method was used to predict the ES. The local strain came into lay first at wk 20, while the imported came into lay at 21 wk of age. The imported layers performed better in ES, FI, HDEP, BWTG, and FCR (P < 0.05) throughout the laying period, while the local layers were better (P < 0.05) in BWT with higher mortality than the imported. Also, the imported layers performed better in FU (P < 0.05) at wk 4, 8, and 24. Among the imported, the highest ES (58.116 g) was obtained from chickens with HDEP of 13.266 < HDEP < 20.35 and FI of 137.95 < FI< 138.176, while in the local layers, the highest ES (54.802 g) was obtained from chickens with HDEP of 37.876 < HDEP < 47.802.