Extraction and Titration of Leukotoxins from Fusobacterium necrophorum Isolates Recovered from Bovine Liver Abscesses in Sulaimaniyah Region

Abstract

This study was conducted to extract and titrate the leukotoxin of Fusobacterium necrophorum isolates recovered from57 abscesses found in 42 livers of slaughtered cattle in Sulaimaniyah region. The culture supernatants of these isolates were subjected to the tetrazolium dye reduction test which revealed that the leukotoxin titer values of 34 F. necrophorum subsp. necrophorum isolates ranged from 128 to 1024 (with a leukotoxin titer mean of 516±46), whereas the leukotoxin titer values of the 11 F. necrophorum subsp. funduliforme isolates ranged from 0 to 128 (with a leukotoxin titer mean of 73±12).