Comparative on Changes in Nasal Microbiota between Healthy Angus Calves and IBRV Infected Calves
Infectious bovine rhinotracheitis virus(IBRV)is a bovine respiratory virus that has a serious impact on the global cattle industry.Based on an epidemiological investigation of IBRV in 1-month-old calves from four large-scale Angus beef cattle breeding farms in the southern Xinjiang region,the impact of IBRV infection on the nasal microbiota of Angus calves was explored.One-month old Angus calves with respiratory symptoms(mainly including fever,cough,and difficulty breathing)were clinically investigated.Nasal swabs were collected from the calves for IBRV PCR detection.Based on the PCR detection results,10 pure IBRV positive calves(Group P)and 10 healthy calves(Group N)with negative IBRV and no other respiratory virus infection were randomly selected,Use 16S rRNA gene sequencing technology,select V3 and V4 variable regions,and use Illumina platform to perform Paired end sequencing on the DNA fragments of nasal microbiota,analyze the composition structure and function prediction of the two groups of nasal microbiota.The results showed that 922 calves had symptoms of respiratory diseases,and the incidence rate was 8.2％(922/11 215);Among them,98 died,with a case fatality rate of 10.6％(98/922).The positive rate of IBRV in the sample test was 22.0％(50/227).Compared with the number of taxonomic units of nasal flora of calves in group N,calves in group P showed a highly significant increase at the level of phylum,class,order,and family(P＜0.01),and a trend towards an increase at the level of genus(P=0.056).In Alpha diversity,there was a significant difference in the coverage and evenness of the two groups of microbiota(P＜0.05),while in Beta diversity,there was a significant difference in the structure of the nasal microbiota between Group P and Group N(P＜0.05).The difference between bacteria and phyla showed that the abundance of Bacillota in group P was significantly lower than that in group N(P＜0.01),and the abundance of Chloroflexota,Acidobacteriota,Cyanobacteria,Gemmatimonadota was significantly higher than that in group N(P＜0.01);The abundance of Planococcus and Salinicoccus in group P were significantly lower than that in group N(P＜0.05),and the abundance of Halomonas and Lactobacillus were significantly higher than that in group N(P＜0.05).There are 9 metabolic pathway changes in the MetaCyc metabolic pathway in group P calves,and 7 metabolic pathway changes in the KEGG metabolic pathway abundance prediction,mainly related to participating in body synthesis,inflammatory response markers,and affecting body growth and development.In addition,there are differences in cellular metabolism,material transportation,decomposition and synthesis,and potential functions of diseases.This study preliminarily revealed a close correlation between IBRV infection and changes in the composition,structure,and function of nasal microbiota in cattle with respiratory symptom diseases,providing a theoretical reference for further exploring the pathogenesis of IBRV infection in calves.
万方数据
维普
