Betaine Supplementation Enhances the Survival Rate of Japanese Quail by Modulating Intestinal Development and Reducing the Growth of Pathogenic Bacteria

Abstract

This study investigated the effects of betaine supplementation on the intestinal development, microbiota composition, and survival rate of Japanese quail (Coturnix japonica) raised in a tropical environment. A completely randomized design was employed with three treatment groups: a basal diet (Control), a basal diet supplemented with 0.12% betaine (BS), and a withdrawal group where betaine was withdrawn (BW). Results indicated that BS significantly increased the lengths of the jejunum and ileum compared to the Control (p<0.05). Furthermore, betaine supplementation significantly enhanced the birds’ survival rate, with BS exhibiting a higher survival rate (p<0.05) compared to the control (95.93% vs. 91.76%). During the withdrawal period, a higher survival rate was observed in the BW group (85.25%) compared to the Control group (79.43%). Microbiological analysis revealed that BS led to a notable reduction in the relative abundance of Clostridium perfringens (p<0.05), with values of 4.08×10⁻¹ in the control group, 1.13×10⁻³ in the BS group, and 1.96×10⁻¹ in the BW group. Betaine had no significant effect on the abundance of Escherichia coli, Clostridium spiroforme or Staphylococcus epidermidis. In conclusion, BS enhances the survival rates of Japanese quail in tropical climates by promoting intestinal development and inhibiting the growth of specific pathogenic gut bacteria.