Bacteriological Studies on Swollen Head Syndrome in Broiler Chickens

Abstract

Swollen head syndrome (SHS) in poultry is a serious problem for the commercial broiler industry causing great economic losses.In the present study, the prevalence of SHS was studied in 500 broiler chickens and identification of the causative bacterial agents was conducted focusing. Samples were collected from the serous fluid from subcutaneous of the infra orbital sinuses. The prevalence rate of SHS in examined broiler chickens was 20%.The results of bacteriological examinationrevealed that 92% samples showed bacterial isolation, 72% of them had single bacterial isolates while 20% had mixed bacterial isolates. On the other hand,8% had negative bacterial isolation.A total of 112 bacterial isolates were recovered. E. coli was the most prevalent; recorded as 80 isolates (60 single and 20 mixed) followed by P. aeruginosarepresented as 24 isolates (11 single and 13 mixed with E. coli), Klebsiella spp. represented as 4 isolates (one single 1% and 3 mixed with E. coli) and finally, Salmonella spp. represented as 4 isolates, all were mixed with E. coli.Results of serogrouping of E. coli isolates revealed that 6 O-serogroups were obtained of which O₁₁₉ was the most prevalent (30%) followed by O₁₈ (23.8%), O₁ (16.3%), O₁₂₅ (15%), O₁₅₈ (8.6%), and finally O₁₆₉ (6.3%).On the other hand, serotyping of Salmonella isolates revealed the existence of the