Split Feeding for semi-heavy laying hens from 105 to 120 weeks of age: Performance, egg quality, biochemical parameters, reproductive tract morphometry and bone quality.

This study evaluated different intensities of split feeding on performance, egg quality, oviposition time, serum biochemical parameters, reproductive tract morphometry, and bone quality of semi-heavy laying hens in the late production phase. A total of 160 Novogen Brown hens (105 weeks of age) were assigned to a completely randomized design with four treatments and five replicates of eight birds. Treatments included: CONTROL, with a standard diet offered twice daily; LIGHT, with a morning diet containing 5% higher crude protein (CP) and metabolizable energy (ME) and 40% lower calcium (Ca), and an afternoon diet with opposite adjustments; MODERATE, with +8% CP, +10% ME, and -50% Ca in the morning and inverse levels in the afternoon; and INTENSE, with +11% CP, +15% ME, and -60% Ca in the morning and inverse levels in the afternoon, relative to the control diet. The experimental period lasted 105 days, and diets were formulated to synchronize nutrient supply with daily physiological demands. No significant differences were observed among treatments for egg production, egg weight, or egg mass, indicating maintenance of productive performance. Split feeding improved egg quality, increasing eggshell strength, Haugh units, and yolk index, especially in the moderate and intense treatments. Oviposition was more concentrated during early hours of the day, facilitating egg collection. The moderate treatment resulted in lower serum urea concentrations and adequate cholesterol and triglyceride levels, indicating improved protein utilization and metabolic balance. Reproductive tract morphometry showed increased height and area of magnum and uterine folds in hens subjected to split feeding. Bone quality, assessed by the Seedor index, was reduced in higher-intensity treatments, indicating greater calcium mobilization without compromising bone mechanical strength. In conclusion, moderate split feeding was the most effective strategy for semi-heavy laying hens between 105 and 120 weeks of age, improving nutritional synchronization, metabolic efficiency, reproductive tract integrity, and egg quality without impairing productive performance.