Effects of beak-treatment styles on beak morphology and production performance of layer chicks aged 0-8 weeks.

Introduction: Double-infrared (IR-D) and laser energy sources (LAS) are two types of newly beak treatment equipment. Although the IR-D and LAS techniques have been developed by changing the number and type of energy sources, their effects on layer chicks are yet to be systematically studied.

Methods: In this study, we placed 4,416 layer chicks into groups subjected to single-infrared energy sources (IR-S), IR-D, and LAS beak treatment on hatching day and a sham untreated control (CON) group; the beak sloughing, growth and histomorphology, body weight (BW), feed intake (FI), and other performance indicators were measured.

Results: Results showed that the beak length at 4 to 8wk in LAS group was significantly higher than that in IR-S and IR-D groups (p < 0.05), and showed a better symmetry. The beak bone mineral density (BMD) and the beak bone mineral content (BMC) at 3-4 weeks was the lowest in the CON group. The BW at 1-4 weeks and the FI at 1 and 3 weeks in the CON group were significantly higher than those in the IR-S and IR-D groups (p < 0.05), whereas there was no significant difference between the BW and FI of the CON and LAS groups from 1 to 8 weeks. The liver weight percentage from 1 to 2 weeks and the bursa Fabricius weight percentage at week 8 in the CON group were significantly higher than those in the experimental groups (p < 0.05).

Discussion: This study concluded that the LAS group had certain advantages in beak length, symmetry, BW, and FI and provided a reference for evaluating the effects of beak treatment methods on layer chicks.