The microbiota structure in the cecum of laying hens contributes to dissimilar H2S production

Abstract

BackgroundHost genotype plays a crucial role in microbial composition of laying hens, which may lead to dissimilar odor gas production. The objective of this study was to investigate the relationship among layer breed, microbial structure and odor production.ResultsThirty Hy-Line Gray and thirty Lohmann Pink laying hens were used in this study to determine the impact of cecal microbial structure on odor production of laying hens. The hens were managed under the same husbandry and dietary regimes. Results of in vivo experiments showed a lower hydrogen sulfide (H2S) production from Hy-Line hens and a lower concentration of soluble sulfide (S2−) but a higher concentration of butyrate in the cecal content of the Hy-Line hens compared to Lohmann Pink hens (P < 0.05), which was consistent with the in vitro experiments (P < 0.05). However, ammonia (NH3) production was not different between genotypes (P > 0.05). Significant microbial structural differences existed between the two breed groups. The relative abundance of some butyrate producers (including Butyricicoccus, Butyricimonas and Roseburia) and sulfate-reducing bacteria (including Mailhella and Lawsonia) were found to be significantly correlated with odor production and were shown to be different in the 16S rRNA and PCR data between two breed groups. Furthermore, some bacterial metabolism pathways associated with energy extraction and carbohydrate utilization (oxidative phosphorylation, pyruvate metabolism, energy metabolism, two component system and secretion system) were overrepresented in the Hy-Line hens, while several amino acid metabolism-associated pathways (amino acid related enzymes, arginine and proline metabolism, and alanine-aspartate and glutamate metabolism) were more prevalent in the Lohmann hens.ConclusionThe results of this study suggest that genotype of laying hens influence cecal microbiota, which in turn modulates their odor production. Our study provides references for breeding and enteric manipulation for defined microbiota to reduce odor gas emission.

Breed Differences in the Expression Levels of gga-miR-222a in Laying Hens Influenced H2S Production by Regulating Methionine Synthase Genes in Gut Bacteria

“…In our previous study, we found a signi cantly higher daily H 2 S production in Lohmann laying hens than Hy-line Gray laying hens (the daily H 2 S production per kg average daily feed intake was 7.75 and 4.17 mg for Lohmann and Hy-line, respectively) [26]. However, whether the H 2 S emission difference between the two breeds of laying hens was due to host miRNA regulation of the gut microbiota requires further investigation.…”

“…In a previous study, we found that Hy-line hens exhibited lower H 2 S production than Lohmann hens as a result of different microbiota structures related to H 2 S production in the cecum [26]. However, due to the limitation of 16S rRNA sequencing, we did not annotate and identify pathways and genes related to bacterial sulfur metabolism.…”

“…To eliminate the confounding effects that might be caused by diet, age, weight and feeding environment. Thirty Hy-line Gray laying hens and thirty Lohmann Pink laying hens at 28 weeks of age with similar weights (1.70 ± 0.02 and 1.71 ± 0.02, respectively for Hy-line and Lohmann) were selected and moved into twelve respiration chambers in an environmentally controlled room for a daily H 2 S production measurement for the two breeds [26]. A commercial-type laying hen diet was fed to birds ad libitum, water was available at all times (Table S1), and a 12-h light cycle at 24 °C room temperature management schedule was used.…”

Breed Differences In The Expression Levels Of Gga-Mir-222a In Laying Hens Influenced H2S Production By Regulating Methionine Synthase Genes In Gut Bacteria

“…In our previous study, we found a signi cantly higher daily H 2 S production in Lohmann laying hens than Hy-line Gray laying hens (the daily H 2 S production per kg average daily feed intake was 7.75 and 4.17 mg for Lohmann and Hy-line, respectively) [29]. However, whether the H 2 S emission difference between the two breeds of laying hens was due to host miRNA regulation of the gut microbiota requires further investigation.…”

“…3A). As above mentioned that gga-miR-222a and gga-miR-10a-5p were both high expression level miRNAs in Hy-line and Lohmann, however, the abundance of gga-miR-222a was signi cantly higher in Hy-line by the comparison of Lohmann, and the abundance of gga-miR-10a-5p was signi cantly lower in Hy-lin by the comparison of Lohmann, in addition, our previous study showed that the amount of H 2 S production was obviously higher in Lohmann by the comparison of Hy-line (the daily H 2 S production per kg average daily feed intake was 7.75 and 4.17 mg for Lohmann and Hy-line, respectively) [29], thus we concluded that gga-miR-222a was the potential additive candidate for the reduction of H 2 S production in the cecum of laying hens, it was much worth to select gga-miR-222a for the further investigation rather than the selection of gga-miR-10a-5p. We found that gga-miR-222a could target two genes that associated with methionine synthase, Odosp_3416 (expressed by the bacterium Odoribacter splanchnicus) and BF9343_2953 (expressed by the bacterium Bacteroides fragilis NCTC 9343) ( Fig.…”