Clinical Signs Of Fowl Cholera In Experimental Immunosuppressed And Non-immunosuppressed Kenyan Indigenous Chickens And Ducks

Abstract

P. multocida causes peracute, a cute and chronic fowl cholera in poultry. Twenty chickens and ducks were inoculated int ra - tracheally with 0.5 ml of 10 8 colony forming units of laboratory maintained str ain NCTC 10322 T of P. multocida, 10 of which were immnunosuppressed with dexamethasone 4 mg/kg body weight for 6 days prior to infection. 15 control chickens or ducks were given 0.5 ml of brain heart infu sion broth, 5 of which were similarly immunosuppress ed. All the birds were observed for clinical signs of fowl cholera for 14 days post - infection. Both indigenous chickens and ducks in the immunosuppressed groups showed lower clinical signs compared t o the non - immunosuppressed birds. No clinical signs were observed in all control birds. However, infected birds manifested anorexia, depression, ruffled feathers, nasal discharges, dyspnoea, ataxia, nervous tics, cyanosis, diarrhea and mucoid mouth discharges. In each bird under observation, the signs recurred s ingly or in combination, at the time of observation. Ataxia, nervous tics and head scratching are additional signs of fowl cholera hereby reported in indigenous chickens and ducks for the first time. There were less clinical signs observed in the immunosup pressed birds and this may, under field conditions, create problems in the detection and clinical diagnosis of fowl cholera