A comparison of the effect of short-acting and long-acting cloxacillin-based dry-cow therapy on somatic cell counts after calving in cows also given internal teat sealants. Issue 1 (2nd January 2018)

• Record Type: Journal Article
• Authors: Whitfield, LK; Laven, RA
• Is Part Of: New Zealand veterinary journal. Volume 66:Issue 1(2018)
• Page Start: 44
• Page End: 47
• Publication Date: 2018-01-02
• Subjects: Dry-cow therapy -- somatic cell count -- cloxacillin -- ampicillin -- long-acting -- short-acting; Veterinary medicine -- Periodicals; Médecine vétérinaire -- Périodiques; 636.089
• DOI: 10.1080/00480169.2017.1386134
• Languages: English
• ISSNs: 0048-0169

Abstract

Abstract : AIM: To compare, in cows treated with an internal teat sealant, the effect of short-acting and long-acting cloxacillin-based dry-cow therapy on somatic cell counts (SCC) after calving. METHODS: Cows from a spring-calving, pasture-based dairy farm in the Manawatu-Whanganui region of New Zealand were randomly allocated to receive either a short-acting cloxacillin and ampicillin dry-cow therapy and internal teat sealant (n=291) or a long-acting cloxacillin and ampicillin dry-cow therapy and internal teat sealant (n=288) at the end of lactation. Cows were managed on-farm with routine husbandry procedures through the dry period and following calving. A multivariable logistic regression model was used to determine the association between length of action of dry-cow therapy and the proportion of cows with a SCC >150, 000 cells/mL at the first herd test after calving. RESULTS: Age of cow, mean SCC for the preceding season and interval from calving to the first post-calving herd test were all associated with the proportion of cows with an individual SCC >150, 000 cells/mL at the first herd test (p<0.001) Treatment with the short-acting dry-cow therapy was not associated with decreased odds of cows having a SCC >150, 000 cells/mL at the first herd test compared with treatment with long-acting dry-cow therapy (OR=0.724; 95% CI=0.40–1.30). CONCLUSIONS AND CLINICAL RELEVANCE: In this herd, which routinely used internal teat sealants, the use of short-acting cloxacillin-based dry-cow therapy did not result in an increased proportion of cows with elevated SSC post-calving. This was a single farm, single year study but indicates that in this herd, changing from a long-acting to a short-acting antimicrobial may have no impact on the prevalence of subclinical mastitis.