Artificial light and biological responses of broiler chickens: dose-response 2

• Published in: Journal of animal science Vol. 96; no. 1; pp. 98 - 107
• Main Authors: Yang, Yefeng, Pan, Chenghao, Zhong, Renhai, Pan, Jinming
• Format: Journal Article
• Language: English
• Published: Champaign Oxford University Press 01.01.2018
• Subjects: Calcium; Calcium ions; Chickens; Conversion ratio; Feed conversion; Light; Light intensity; Luminous intensity; Meta-analysis; Metabolism; Poultry; Productivity; Regression analysis; Statistical analysis; Weight reduction
• DOI: 10.1093/jas/skx044
• ISSN: 0021-8812

Light intensity is an important aspect for broiler production. However, previous results do not provide a solid scientific basis for quantifying the response of broilers to light intensity. This study performed a meta-analysis to model the response of broilers to 0.1-200 lux of light intensity. Meta-analysis was used to integrate smaller studies and increase the statistical power over that of any single study and explore new hypotheses. The results indicated that light intensity <5 lux caused welfare concern (P < 0.05) and light intensity <1 lux induced productivity loss of broiler (P < 0.05), whereas greater level of light intensity >10 lux led to increased mortality (P < 0.01) and decreased uniformity (P < 0.05). Meta-regression showed that 30-200 lux light intensity was negatively related to BW (P = 0.047) and feed intake change (P = 0.054), whereas a quadratic relationship was observed between feed conversion ratio change and 50-180 lux light intensity (R2 = 0.95). In addition, the majority of carcass characteristics (abdominal fat weight and wing weight) and metabolic indicators (K+, Ca2+, and T3) were affected by light intensity >5 lux. To conclude, this meta-analysis based on published data quantitatively identified that 5 lux of light intensity during grow-out period should be the minimum level to maintain a well productivity and welfare of broiler chickens.