Prevalence of minor udder pathogens after intramammary dry treatment.
A total of 156 dairy cows was randomly assigned to one of four groups at drying off over an 18-mo period: untreated control or intramammary treatment of each mammary quarter with either 400 mg novobiocin, 300 mg cephapirin, or 1 g dihydrostreptomycin with 1 million units penicillin. Quarter foremilk samples were aseptically collected from each cow within 1 mo of drying off and within 1 mo after parturition for bacteriological analysis. Prior to drying off, 28.7% of quarters were positive of which 46.7% were Corynebacterium bovis and 45.5% were coagulase-negative staphylococci. Reductions in infection prevalence from drying off to postpartum samplings for control, novobiocin, cephapirin, and streptomycin-penicillin groups were 13.6, 60.5, 74.4, and 35.3% of quarters. Recovery rates for C. bovis infections were 47.6, 100, 100, and 94.1%; for coagulase-negative staphylococci infections they were 72.7, 86.4, 80.0, and 100%. The cephapirin group showed the lowest new infection rate (1.3%) with coagulase-negative staphylococci compared with control (6.9%). There were no significant differences in lactation milk production among groups following dry period therapy. Results suggest that dry treatment reduces the prevalence of infections by the minor mastitis pathogens.
Harmon
R J
RJ
Crist
W L
WL
Hemken
R W
RW
Langlois
B E
BE
D000818:Animals; D002417:Cattle; D002514:Cephapirin / Q000627:therapeutic use; D003354:Corynebacterium Infections / Q000188:drug therapy / Q000662:veterinary; D004096:Dihydrostreptomycin Sulfate / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D005260:Female; D008321:Mammary Glands, Animal / Q000382:microbiology; D008414:Mastitis, Bovine / Q000188:drug therapy* / Q000382:microbiology; D008892:Milk / Q000382:microbiology*; D009675:Novobiocin / Q000627:therapeutic use; D010402:Penicillin G Procaine / Q000627:therapeutic use; D049590:Postpartum Period; D011247:Pregnancy
D009675:Novobiocin; D010402:Penicillin G Procaine; D002514:Cephapirin; D004096:Dihydrostreptomycin Sulfate