Effects of Dietary Indole-3-Acetate Sodium on Laying Performance, Egg Quality, Serum Hormone Levels and Biochemical Parameters of Danzhou Chickens

SIMPLE SUMMARY: The laying performance of hens plays a major role in the production of laying hens because it determines the economic benefits of farmers. Indole-3-acetate sodium is a derivative of indole-3-acetate (a major plant growth hormone). This study shows that indole-3-acetate sodium inclusion in diets improved the serum reproductive hormone levels and egg production performance of Danzhou chickens. We found that indole-3-acetate sodium could be considered as an effective feed additive to improve the laying performance of hens, but more comprehensive studies need to be performed in the future. ABSTRACT: This study was conducted to investigate the effects of indole-3-acetate sodium (IAA-Na) inclusion in diets on the egg production performance, egg quality, intestinal tissue morphology, serum hormone levels and biochemical parameters of Danzhou chickens to preliminarily explore the efficacy of IAA-Na as a feed additive. A total of 192 Danzhou chickens (50 weeks old) were randomly assigned to 2 groups of 96. The diets for the treatment group consisted of the basal diets, supplemented with IAA-Na (200 mg/kg). The formal feeding trial lasted for four weeks. The results showed that the feed supplemented with IAA-Na not only increased the laying rate (p < 0.05) and egg yolk ratio (0.05 < p < 0.1), but also significantly reduced the feed:egg ratio (p < 0.05). In addition, the dietary supplementation of IAA-Na significantly increased the serum estradiol levels (p < 0.05) and decreased serum alkaline phosphatase activity (p < 0.05). Compared with the control group, the addition of IAA-Na to the diet had no significant effect on the intestinal tissue morphology or serum antioxidant capacity of Danzhou chickens. This study preliminarily provides evidence that dietary IAA-Na can improve laying performance, indicating that IAA-Na is a potentially effective feed additive for laying hens, but further studies are required before arriving at definite conclusions.