K. Barth et Wd. Kraetzl, Influence of a treatment of subclinical mastitis on electrical conductivity of milk before let-down, BERL MUN TI, 113(11-12), 2000, pp. 440-443
Citations number
16
Categorie Soggetti
Veterinary Medicine/Animal Health
Journal title
BERLINER UND MUNCHENER TIERARZTLICHE WOCHENSCHRIFT
10 cows (German Brown x Brown Swiss) with 29 infected quarters (14 Staphylo
coccus aureus, 10 esculin positive streptococci, 5 Staphylococcus spec.) we
re treated daily after morning milking over a period of 4 days. Ampicillin
and cloxacillin (500 mg each per dose) were administered to all 40 quarters
intracisternally. During the evening milkings on 4 test days (day 3 before
treatment, day 1 of treatment, days 5 and 9 after the last treatment), ele
ctrical conductivity based on 25 degreesC (EC) was measured in fore milk. T
o avoid ejection of alveolar milk, EC measurement was the first contact to
the udder. Independent of the initial level, EC of all quarters was elevate
d by 2.1 mS/cm on average at the first milking following the first treatmen
t. 9 days after the end of treatment, EC had declined to the initial level
in all quarters classified as mastitic, non specific and latent infected be
fore treatment. By contrast, EC values of healthy quarters remained elevate
d compared to their initial level (p < 0.01). This might be due to increase
d cistern tissue permeability caused by mechanical and pharmacological effe
cts of antibiotic treatment. Despite the fact that somatic cell count and t
otal bacteria count were reduced by treatment (p < 0.01), results showed th
at EC measurement on the first days following treatment was unsuitable for
checking the success of treatment.