A LONGITUDINAL-STUDY OF GREEN-LIVER OSTEOMYELITIS COMPLEX IN COMMERCIAL TURKEYS

Two Becks of Nicholas tom turkeys from separate farms with histories o f above-average condemnations for turkey green-liver osteomyelitis com plex (TOC) were studied throughout a 16-week growout. Fifty birds from each farm were necropsied each week for 15 weeks, and birds that had green livers, osteomyelitis in the proximal tibia, or swollen joints w ere cultured for aerobic bacteria along with an equal number of contro l birds. At processing, TOC lesions and green livers were obtained for bacterial culture and histopathology. Green-liver-associated TOC was not observed until. the turkeys were 9 or 10 weeks of age. The inciden ce of TOC was higher on one farm, which also had a higher incidence of airsacculitis, higher early and weekly mortality, seroconversion to N ewcastle disease virus and Mycoplasma meleagridis, and significantly h igher average body weights, relative spleen weights, and relative live r weights. Both farms had a high incidence of intestinal lesions and i nfestation with Ascaridia dissimilis. Histological evaluation of green livers revealed hyperplasia of bile ducts, dilation of sinusoids, and pigment-containing Kupffer's cells, some of which stained positive fo r iron. The bacterial isolates most frequently cultured from bones and livers were pleomorphic gram-variable coccobacilli, which grew visibl e colonies only after a series of subcultures and extended incubation.