Using tomato, apple, and carrot pomaces as a non-fasting method for molt induction in laying hens

The present study was conducted to investigate the effect of agricultural wastes as a non-fasting method on inducted molting, productive performance, immune response, and blood parameters of laying hens with five experimental treatments and five replicates, including seven birds in each replicate. Dietary treatments consisted of feed withdrawal, apple peel waste, carrot pomace, tomato pomace, and zinc oxide (20 g/kg). The results indicated feed intake in pomace groups decreased significantly (P<0.05). Molting methods did not affect body weight reduction. The zinc group was the lowest egg production in during the molting time, and apple peel waste and tomato pomace groups significantly increased compared to the zinc oxide group in resting time (P<0.05). In days 5 and 11 of molting, heterophil to lymphocyte ratios were significantly lower in the pomace groups than in the feed withdrawal group (P<0.05). Pomace treatments had no significant effect on the egg quality, except for carrot pomace and tomato pomace groups, which increased the yolk color (P<0.05). The lowest level of triglyceride was related to pomaces, the highest levels of cholesterol and MDA were attributed to the feed withdrawal group, and the highest levels of glucose were reported for the tomato pomace, which were statistically significant compared with the control group (P<0.05). Ovary and oviduct weights were significantly lower in the pomace groups than the zinc oxide group (P<0.05). In conclusion, using tomato pomac or apple peel waste as a non-fasting molting method can be an effective alternative to the feed withdrawal method.