Analysis of excreta bacterial community after forced molting in aged laying hens

Abstract

ObjectiveAs laying hens become aged, laying performance and egg quality are generally impaired. One of the practical methods to rejuvenate production and egg quality of aged laying hens with decreasing productivity is a forced molting. However, the changes in intestinal microbiota after forced molting of aged hens are not clearly known. The aim of the present study was to analyze the changes in excreta bacterial communities after forced molting of aged laying hens.MethodsA total of one hundred 66-wk-old Hy-Line Brown laying hens were induced to molt by a 2-d water removal and an 11-d fasting until egg production completely ceased. The excreta samples of 16 hens with similar body weight were collected before and immediately after molting. Excreta bacterial communities were analyzed by high-throughput sequencing of bacterial 16S rRNA genes.ResultsBacteroidetes, Firmicutes, and Proteobacteria were the three major bacterial phyla in pre-molting and immediate post-molting hens, accounting for more than 98.0%. Lactobacillus genus had relatively high abundance in both group, but decreased by molting (62.3% in pre-molting and 24.9% in post-molting hens). Moreover, pathogenic bacteria such as Enterococcus cecorum and Escherichia coli were more abundant in immediate post-molting hens than in pre-molting hens. Forced molting influenced the alpha diversity, with higher Chao1 (p = 0.012), phylogenetic diversity whole tree (p = 0.014), observed operational taxonomic unit indices (p = 0.006), and Simpson indices (p<0.001), which indicated that forced molting increased excreta bacterial richness of aged laying hens.ConclusionThis study improves the current knowledge of bacterial community alterations in the excreta by forced molting in aged laying hens, which can provide increasing opportunity to develop novel dietary and management skills for improving the gastrointestinal health of aged laying hens after molting.

Effects on Intestinal Mucosal Morphology, Productive Parameters and Microbiota Composition after Supplementation with Fermented Defatted Alperujo (FDA) in Laying Hens

“…Similar results have been reported by other studies [44,46]. Decreased microbial diversity has been related to a reduction in the production of short chain fatty acids, which leads to reduced intestinal barrier function [48]. According to some studies and in contrast to adult hens, Firmicutes abundance in pullets is expected to be higher than that of Bacteroidetes [44,46].…”

“…Microbiota composition in poultry, especially in laying hens, has become an important area of research in veterinary medicine [27]. Although some studies have focused on microbiota variation in laying hens at different phases [44][45][46][47] and under diverse production systems [47,48], analyses of microbiota in laying hens fed with plant-derived supplements is limited [49,50]. Given the main role of microbiota in fermentation and digestive processes in laying hens [47], we focused on its composition in the cecum in our analyses.…”

Transcriptomic Analysis of Laying Hens Revealed the Role of Aging-Related Genes during Forced Molting

“…The most obvious manifestations are the regrowth of new feathers, decreased mortality rate, improved eggshell quality [15][16][17][18], and gradual recovery of ELR to SPEP, which is higher than the premolting level [2]. Additionally, the abundance of bacteria in the feces [19] and bone strength [20,21] are also higher than before. Therefore, FM of hens is of substantial importance to increase the utilization life of aging hens.…”

Perches as Cooling Devices for Reducing Heat Stress in Caged Laying Hens: A Review

“…Induced molting (traditional fasting molt and recently developed non-feed withdrawal molt) is a management strategy to rejuvenate hens’ reproductive systems at the end of the laying cycle, and then bring the flock into a second laying cycle based on the egg market demand and reduce bird production cost per dozen eggs [ 16 ]. Fasting molt also changes gut microbiota composition, reducing Lactobacillus genus and increasing pathogenic bacteria such as Enterococcus cecorum and Escherichia coli in aged laying hens [ 17 ], consequently suppressing immunity. Non-feed withdrawal molting by providing low-energy ingredients (such as wheat middlings, corn distillers dried grains with solubles, or corn diets) may negatively affect laying hens as low energy diets may not lead to satiated feeding, even though the crop and proventriculus may be distended following ingestion [ 18 ].…”