ABSTRACT This study aimed to evaluate the effects of adding Moringa oleifera leaf powder (MOLP) to the basal diets of chickens at late laying period on clutch trait, reproductive organs, serum reproductive hormones and reproduction-related genes expression. A total of 350 hens (37 weeks old) with similar laying rate and clutch trait were randomly allocated into five groups, and fed 0 (Control, CON), 2.5 (MOLP2.5), 5, 7.5 and 10% MOLP supplemented diets for 6 weeks. The hens supplemented with 2.5% MLOP had the average clutch length, clutches and clutch intensity close to those in CON. The numbers and weight of hierarchal follicle were significantly increased at the supplementation 2.5% MOLP group. The estrogen concentration was highest in MOLP2.5 group and lowest in MOLP10 group. Expression levels of steroidogenesis-related genes of StAR and Cyp19a1 were higher in MOLP2.5, MOLP5 and MOLP7.5 groups compared with that in the control. These findings suggested that dietary supplementation with 2.5% MOLP effectively increased hierarchal follicle numbers, estrogen level and gene expression of StAR and Cyp19a1, which has a potential beneficial effect on laying performance in laying chicken.

ABSTRACT Background: Eggshell ultrastructure organization, including effective layer thickness, mammillary layer thickness, and average size of mammillary cones, is important for breeding and significantly influences eggshell mechanical properties. Several matrix proteins were known to be important in eggshell formation. However, the proteins and variations that determine eggshell ultrastructure organization are not known. Results: In this study, 17 single-nucleotide polymorphisms of three major genes in a hen population using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Five single-nucleotide polymorphisms with a very low minor allele frequency (< 1%) were excluded from further analysis. The remaining 12 single-nucleotide polymorphisms in Hardy-Weinberg equilibrium were used for analysis of associations with eggshell ultrastructure organization. Associations were found for (i) ovocleidin-116 with effective layer thickness (EFF), mammillary layer thickness (MAM), and average size of mammillary cones (SMAM); (ii) ovalbumin with eggshell thickness (ESH), effective layer thickness, and density of the mammillary cone (DMAM); and (iii) calmodulin1 with density of the mammillary cone. Conclusions: The single-nucleotide polymorphisms identified in the present study may be used as potential markers to improve eggshell quality.