Figure 1.

Survival percentages, CCS and bacterial scores. (a) Survival of broiler chickens following E. coli challenge. Groups of broiler chicken embryos at day 18 of incubation were injected with 50 µg of CpG-ODN or saline by the in ovo route (n = 32 CpG-ODN, n = 36 saline group). Birds that received CpG-ODN were significantly protected against E. coli infection compared to the saline control group (P = 0.04). (b) Cumulative clinical scores (CCS) of broiler chickens following E. coli challenge with either 1 × 10⁴ or 1 × 10⁵ cfu of E. coli. Groups of birds that received 50 µg CpG-ODN CpG-ODN had a significantly lower CCS compared to the saline group, (P = 0.03). Bar = mean. (c) Bacterial scores of swabs taken from airsacs of birds. Higher bacterial scores indicate greater bacterial load. Increased bacterial growth was observed more frequently in lesions from birds in the saline group than in the CpG-ODN group. The substantial number of ‘0’ or ‘no growth’ of bacteria in both groups is a common finding in such experiment.