Experimental Histopathologic Studies on Pasteurella Multocida Infection in Chicken and Ducks

One hundred and eighty six balady chickens and 186 pekin ducksof 3-weeks age, were divided into 3 groups to study the pathogenesis andthe pathological changes of Pasteurella multocida infection irforrelationto different routes and duration of infection.Experimental groups were treated as follow:I Group.(I) chickens and group (IV) ducks containing 2 subgroupsIII each, each subgroup in both groups was injected !./M. with either 1 mlI or ’0.2 ~l I{ chicken or duck of (3x108) of Pasteurella multocidarespectively.Group (11) chickens and group (V) ducks containing 2 subgroupsIII each, each subgroups in both groups was inoculated 1.1N. with either 1ml or 0.2 ml/ chicken or duck of(3x108) ofP. multocida respectively.Group (Ill) chickens and group (VI) ducks containing 2 sub-groups in each, each subgroup in both groups was served ’as untreatedcontrol in either chickens or ducks.The chickens and ducks in all subgroups which received high doses, 1 ml of (3x108) ofP. multocida were sacrificed 1,3,7 and 9-days P.I. butthe chickens and ducks in all subgroups which inoculated with low doses0.2 ml of(3x108) of P. multocida were sacrificed 35, 45 and 60-days P.I ..The mortalities were seen only in group (1) and reached 67.9% within 2-days P.!. and 59.8% within 5-days P.!. in subgroup (A) and subgroup (B) respectivetly.The clinical signs among the inoculated birds were mainly whitish diarrhea, loss ’of appelite, loss of feather anddecrease of body weight in the birds, which, treated with high dose ofmicroorganism. Emaciation and swelling in the joints Q fi ..; birds, which,