The effect of the challenge with Newcastle disease virus on the gastrointestinal bacterial population in Japanese quail (Coturnix japonica)

Newcastle disease (ND), caused by virulent strains of Newcastle disease virus (NDV), is a devastating disease of poultry worldwide. The effect of a challenge with NDV on bacterial population in quail is poorly documented, so for this purpose, a total of 100 day-old Japanese quail were purchased and divided into 2 equal groups randomly. Each group was divided into 2 subgroups. The birds in group A challenged with a velogenic chicken isolate of NDV. The birds in group B did not challenge with NDV as the control group. For the determination of lactobacillus counts in the intestine and crop of Japanese quail, at the end of the period, 10 birds of each subgroup were chosen randomly. One gram of the crop and ileocecal content were taken and cultured on MRS for determination of lactobacillus counts. The colony-forming units of Escherichia coli in digesta of ileocecal on Mac Conkey agar were investigated. The results of this study showed that the challenge with a velogenic chicken isolate of NDV could increase colony-forming units of Escherichia coli in group A compared to the control group. Also, it reduced lactobacillus counts of intestine and crop compared to the control group. So it concluded that velogenic chicken isolate of NDV influences microflora of intestine and crop of Japanese quail.