Lighting programme as a management tool for broilers raised without antibiotics - impact on productivity and welfare

Area of Science:

• Animal Science
• Poultry Science
• Animal Welfare

Background:

• Antibiotic use in poultry production is a growing concern.
• Understanding environmental factors like lighting is crucial for broiler welfare.
• Photoperiod management is a key strategy in modern broiler rearing.

Purpose of the Study:

• To evaluate the effects of different photoperiods on the productivity and welfare of broilers reared without antibiotics (RWA).
• To determine optimal lighting conditions for RWA broiler performance and well-being.

Main Methods:

• 8,064 Ross 308 broilers were used across two trials.
• Lighting treatments included 14L:10D, 17L:7D, 20L:4D, and 23L:1D.
• Productivity (body weight, feed conversion, uniformity) and welfare indicators (heterophil/lymphocyte ratios, gait, footpad scores, behavior, condemnations) were assessed.

Main Results:

• The 4D (20L:4D) photoperiod resulted in the highest body weights and feed consumption.
• Improved feed conversion was observed with longer dark periods (shorter photoperiods).
• Welfare issues, including higher stress (heterophil/lymphocyte ratios), poorer mobility, and increased footpad lesions, were associated with longer photoperiods.

Conclusions:

• Extended photoperiods negatively impact broiler welfare, indicated by reduced mobility, increased stress, and footpad lesions.
• Shorter dark periods (longer photoperiods) led to increased feeding behaviors and environmental pecking.
• The 7D (17L:7D) photoperiod showed the lowest condemnation rates, suggesting a potential welfare benefit.