Studies on the Role of Free Living Birds as a Source of Pathogenic Escherichia coli infection to Chickens

El-Shazly, M; Hassan, A; ElJakee, J; Youssef, Y

doi:10.21608/vmjg.2016.363159

Studies on the Role of Free Living Birds as a Source of Pathogenic Escherichia coli infection to Chickens

Authors

¹ Veterinarian at Desouk Veterinary Unit, Kafr el-Sheikh Province, Egypt.

² Department of Microbiology, Faculty of Veterinary Medicine, Cairo University, Egypt.

³ Department of Poultry and Rabbit Diseases, Faculty of Veterinary Medicine, Cairo University, Egypt.

10.21608/vmjg.2016.363159

Abstract

This study investigated the prevalence of pathogenic E. coli in internal organs (liver, heart and spleen) of 75 broiler chickens representing 15 broiler chicken flocks showing respiratory manifestations and 60 free living birds (25 House sparrows, 15 Doves, 16 Cattle egrets and 4 white throated-King fishers) inside and in the same vicinity of previously sampled broiler chicken flocks in different localities of Kafr el-Sheikh province, Egypt from late 2013 up to early 2015. The results revealed 48 (64 %) isolates out of 75 broiler chicken samples, whereas 10(16.67%) isolates out of 60 free living bird samples. Invitro pathogenicity test using Congo red assay showed that out of 48 isolates from broiler chicken 22 (45.8 %) showed Congo red positive, whereas out of 10 isolate from free living birds 5 (50 %) showed Congo red positive. Serotyping was carried out on 5 selected Congo red positive isolates of broiler chickens and all 10 isolates of free living birds. Three E. coli serogroups belong to 044, O55 and 0157 strains from broiler chickens and six serogroups belong to 0128, O55, 0136, 0127 and 0164 strains from free living birds; were subjected to in vivo pathogenicity assay in one- day specific pathogen free (SPF) chicks. The pathogenicity in day-old SPF showed 100 % mortality with strain 0136 (House sparrow origin), 80 % mortality with the strain 044 (broiler chicken origin), 40 % mortality with strain O55 (Dove origin), 20 % with both strains; 0157 (chicken origin) and 0128 (House sparrow origin), whereas other strains; O55 (chicken origin), O55 (House sparrow origin), 0127 (Dove origin) and 0164 (Cattle egret origin) did not caused any mortality in day-old chicks. The study suggested that free living birds may play an important role in prevalence and introduction of pathogenic strains of E. coli to broiler chicken farms.

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