ABSTRACT
Investigation of the presence of R. anatipestife r in Rasht area [North of Iran]. 109 domestic ducks and 33 hen and rosters . Samples were collected from pasteurellosis suspected birds on the basis of clinical signs and gross lesions. Tissue samples from liver, lungs, air sacs, heart blood and synovial fluid of each suspected birds were cultured on blood agar according routine methods. The cultures were incubated under candle jar at 37 c for 24-72 hours. Isolated pasteurella spp. Was identified on the basis of colony and cell morphology and biochemical reactions. Isolates of Riemerella assigned to species according Rimller 1998. P. multocida was isolated from 46 [42.2ko[3]/41] out of 109 ducks, and from 12 [63.3ko%l] of 33 hen and rosters. R. anatipestifer was isolated from 13 [11.9ko[3]/41] ducks but nither from hens nor from rosters. Other species of pasteurella viz. P. gallinarum and P. hemolytica were not isolated. Antimicrobial sensitivity test of isolated Riemerella showed that the most sensitive antibiotics were flumoquine, trimetoprim with 92.3ko[3]/41 and the most resistance antibiotics was oxytetracycline [30.8ko[3]/41] and penicillin [23.Iko[3]/[41]. This investigation revealed that R. anatipestifer is present in domestic Ducks in this area, but not in domestichen and rosters