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Ornithobacterium rhinotracheale (ORT) has been associated with avian respiratory disease. On coinfection with other pathogens, ORT can cause serious health problems in avian species, leading to financial losses. To monitor the serologic prevalence of ORT in chicken flocks in China, 1,280 sera were collected to determine ORT antibodies among 64 flocks from 15 provinces of China using a commercial ELISA kit. The overall seroprevalence of ORT among the birds tested was 44.06%. In younger chickens, the serum positive rate was lower than that in older chickens, and with increased age, the serum positive rates increased. Older chickens had not only higher positive rates but also higher antibody levels. These data indicated that ORT infections were common in China. Because an ORT vaccine is currently not available, good disease management and biosecurity measures are required for effective disease control.

Infectious coryza (IC), an acute respiratory disease of chickens, is caused by Avibacterium paragallinarum. Here, the current epidemiological status of IC was investigated in China over 5 yr (2013 to 2018). A total of 28 Av. paragallinarum field isolates were identified by PCR tests and by sequence analysis of the hemagglutinin gene. The pathogenicities of 4 field isolates, the efficacy of 2 commercial inactivated oil-emulsion IC vaccines and vaccines containing different Av. paragallinarum isolates were also evaluated. The PCRs revealed a high rate (51.5%) of sample positivity for Av. paragallinarum during 2013 to 2018. Phylogenetic analysis showed that most field strains fell into the same cluster and had a farther genetic relationship with the early isolates from China. Pathogenicity testing revealed that the Chinese Av. paragallinarum isolates were able to induce the typical clinical signs of IC; hence, they were clearly pathogenic to chickens. Vaccine efficacy tests revealed that the 2 commercial inactivated oil-emulsion IC vaccines we tested had low protection rates against 2 selected Av. paragallinarum isolates after a single immunization, whereas the inactivated vaccine containing the Av. paragallinarum BJ26 isolate generated a relatively high protection rate against the field isolates compared with other three tested vaccines. The results indicate that IC is currently prevalent in China, and that commercial vaccines have not counteracted its presence in this country.

In present study, the content of main nutrients in wild coix seed were significantly higher than cultivated coix seed. Transcriptome and proteome were combined to provide new insight of the molecular mechanisms linked to nutritional quality of wild coix seed and cultivated coix seed by RNA sequencing and isobaric tags for relative and absolute quantification techniques. A total of 20,039 genes and 471 proteins exhibited differential expression level in cultivated coix seed when compared with wild coix seed. These genes and proteins revealed that the pathway of flavonoids biosynthesis, starch and sucrose metabolism, lipid metabolism and amino acid metabolism were linked to nutritional quality of coix seed. Our results provided transcriptomics and proteomics information with respect to the molecular mechanisms of nutritional changes of coix seed, identified key genes and proteins that associated with the metabolism and accumulation of nutrients, and helped clarify the mechanisms of nutrient differences.