Interpretive Summary: Immunoglobulin-Y versus Tylosin phosphate for the treatment of liver abscess in Holstein Steers
By: Anne Kamiya, MS
Liver abscesses in feedlot cattle negatively impacts both growth performance and carcass value. Abscesses are typically caused by anaerobic bacteria such as Fusobacterium necrophorum or Trueperella pyogenes and are treated with the macrolide antibiotic Tylosin phosphate (TYL). However, antibiotic resistance is becoming increasingly problematic, necessitating other ways to remedy liver abscesses. Among potential alternatives is immunoglobulin-Y (IGY), a targeted antibody harvested from egg yolks.
The authors of this recent Translational Animal Science study fed IGY to Holstein steers to determine its effectivity in treating or preventing liver abscesses. They also evaluated how growth performance and carcass value were impacted by the estimated duration of abscess presence (DUR).
Holstein steers on a 188-day finishing diet were fed either IGY specifically targeted for F. necrophorum and T. pyogenes bacteria or TYL. Monitoring of feed intake, body weight and liver ultrasounds followed the development and duration of liver abscesses. No difference was noted in the growth performance of TYL versus IGY cattle, but carcass value was notably higher in TYL cattle. Abscess severity and DUR in TYL versus IGY cattle was unremarkable. Duration of abscess presence, regardless of feed additive or abscess severity, significantly negatively impacted growth performance and carcass value when persisting for 140 days or more.
Overall, the results of this study did not find IGY to be an effective replacement for TYL. Longstanding abscesses regardless of severity had significant negative impacts on growth performance and carcass value, emphasizing the need to find more effective ways to remedy this condition. More research into alternative ways to treat and prevent liver abscesses in Holstein steers is justified.
The original article, Evaluation of Immunoglobulin-Y in Place of Tylosin Phosphate in the Diets Fed to Holstein Steers and Preliminary Analysis of Liver Abscess Duration on Animal Growth Performance, will be viewable online in Translational Animal Science.