Utilization of protozoal selenium in young goats

The effects of Selenohomolanthionine supplementation on the rumen eukaryotic diversity of Shaanbei white cashmere wether goats

Selenium (Se) is an important microelement for animal health. However, the knowledge about the effects of Se supplementation on rumen eukaryotic community remains less explored. In this study, the ruminal eukaryotic diversity in three months old Shaanbei white cashmere wether goats, with body weight (26.18 ± 2.71) kg, fed a basal diet [0.016 mg/kg Se dry matter (DM), control group (CG)] were compared to those animals given basal diet supplemented with different levels of organic Se in the form of Selenohomolanthionine (SeHLan), namely low Se group (LSE, 0.3 mg/kg DM), medium Se group (MSE, 0.6 mg/kg Se DM) and high Se group (HSE, 1.2 mg/kg DM) using 18S rRNA amplicon sequencing. Illumina sequencing generated 2,623,541 reads corresponding to 3123 operational taxonomic units (OTUs). Taxonomic analysis revealed that Eukaryota (77.95%) and Fungi (14.10%) were the dominant eukaryotic kingdom in all samples. The predominant rumen eukaryotic phylum was found to be Ciliophora (92.14%), while fungal phyla were dominated by Ascomycota (40.77%), Basidiomycota (23.77%), Mucoromycota (18.32%) and unidentified_Fungi (13.89%). The dominant eukaryotic genera were found to be Entodinium (55.44%), Ophryoscolex (10.51%) and Polyplastron (10.19%), while the fungal genera were dominanted by Mucor (15.39%), Pichia (9.88%), Aspergillu (8.24%), Malassezia (7.73%) and unidentified_Neocallimastigaceae (7.72%). The relative abundance of eukaryotic genera Ophryoscolex, Enoploplastron and fungal genus Mucor were found to differ significantly among the four treatment groups (P < 0.05). Moreover, Spearman correlation analysis revealed that the ciliate protozoa and fungi were negatively correlated with each other. The results of this study provided newer information about the effects of Se on rumen eukaryotic diversity patterns using 18s rRNA high-throughput sequencing technology.

The effects of organic selenium supplementation on the rumen ciliate population in sheep

The effect of selenium supplementation on the rumen protozoan population of sheep was demonstrated. Both the total and generic counts of rumen ciliates in sheep fed a diet with basal Se content (70 microg/kg dry matter) were compared to those of animals given feed supplemented with inorganic (disodium selenite) or organic Se (selenized yeast) (310 microg/kg dry matter). The genera of Entodinium, Isotricha, Dasytricha, Ophryoscolex, Diploplastron and Polyplastron occurred in all sheep except for the control, in which Ophryoscolex was not observed. The population of Ophryoscolex caudatus f. tricoronatus was significantly higher in sheep supplemented with organic Se than in animals given inorganic Se (by 160 %). Supplementation of feed with selenized yeast induced significant growth in the Diploplastron population (by 63 %) while no change occurred in sheep given selenite. The populations of Dasytricha ruminantium and Polyplastron multivesiculatum were higher than control in both Se-supplemented groups. The ciliate population of Entodinium spp. was not influenced by Se supplements. Our results suggest a protective effect of Se feed supplementation on the development of some rumen ciliate species in young ruminants.