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.
R J
RJ
Harmon
W L
WL
Crist
R W
RW
Hemken
B E
BE
Langlois
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