Combined use of Candida Utilis and Idesia polycarpa var. Vestita Fruit Improve the Production Performance of Laying Quail

Although Idesia polycarpa oil has been wildly explored as a raw material for biodiesel, the reports studying the by-product Idesia polycarpa fruit residues (IPR) are few. This study aimed to evaluate the effect of the Idesia polycarpa fruit residues fermented feed additive (IPFF) on the egg production of laying quails. The egg production and related performances include egg quality, yolk cholesterol, yolk fatty acid, quails jejunum morphology, and relative gene expression were determined in this study. Compared to the standard diet group, birds fed the 1% IPFF showed a higher egg production (87.7% on average, 11.5% above the control; P<0.01). The yolk fatty acid composition and n6/n3 ratio were affected by IPFF or IPR. Compared to the standard diet group, the egg cholesterol content was lower in both IPFF and IPR groups, and the yolk n6/n3 ratio in the 5% IPFF group (10.3; P<0.01) was more reasonable. Meanwhile, birds under IPFF dietary supplement showed a thicker jejunum wall, higher villus, and deeper crypt than the standard diet group. In addition, the altered mRNA expression of four genes involved in cholesterol and fatty acids metabolism (SREBP-1, SREBP-2, ADGL, APOVLDL-II) in the 1% IPFF group and 5% IPR group indicated that the lipids metabolism and transportation were enhanced in the interclavicular fat pad and liver, relative to the standard diet group. HIGHLIGHTSEgg production was higher in IPFF groups Egg cholesterol was lower in IPFF groups Lipid metabolism and transportation was enhanced in IPFF groups Intestine wall was thicker in IPFF groups