ADSA-SAD Undergraduate Dairy Production Oral Competition

摘要

An active compound of citrus oils (CO), citral, contributes to thebactericidal activity of CO and serves as a non-antibiotic alternativecandidate for the treatment of bovine Escherichia coli mastitis. Duringtimes of inflammation, monitoring the immune response can generateeconomic and welfare benefits due to the high incidence of mastitisacross the dairy industry. The objective of this study was to evaluate theimmune response after being challenged with mastitis pathogen E. colistrain P4. Eighteen healthy, multiparous Holstein cows in mid-lactation(>100 d in milk) were challenged with 800 cfu of E. coli strain P4 intoone rear mammary quarter. One of 3 intramammary treatments wereadministered into the infected quarter ～24 h post-infection including: 1)CON: sterile phosphate buffer solution twice daily, 2) CO: 1.0% (vol/vol) citral twice daily or 3) AB: ceftiofur hydrochloride once daily (basedon label instructions). Coccygeal blood was collected daily through d7 post-challenge where serum was harvested. Serum haptoglobin wasanalyzed using a commercially available kit (Tridelta DevelopmentLimited, Dublin, Ireland). Data were analyzed using ANOVA of thePROC MIXED procedure of SAS v.9.4. The results indicated thatserum haptoglobin was not different by treatment (P = 0.55) or for theinteraction of treatment by day of challenge (P = 0.97). In conclusion,CO does not alter serum haptoglobin response even when comparedwith the control during E. coli bovine mastitis and CO may not serveas an alternative treatment for bovine mastitis infection with a gramnegativeorganism.