Use of systemic disease signs to assess disease severity in dairy cows with acute coliform mastitis.
OBJECTIVE
To evaluate the use of systemic disease signs for classifying severity of acute coliform mastitis in dairy cows.


METHODS
Prospective cohort study.


METHODS
144 dairy cows.


METHODS
Cows were examined at the time of initial identification of disease (time 0) and classified as having mild, moderate, or severe disease on the basis of rectal temperature, hydration status, rumen contraction rate, and attitude. A CBC and serum biochemical analyses were performed, and milk samples were submitted for bacterial culture at time 0 and 48 hours later.


RESULTS
69 cows were classified as having mild disease, 44 as having moderate disease, and 31 as having severe disease. Median WBC and neutrophil counts were significantly lower in cows with moderate or severe disease at time 0 than in cows with mild disease. Band neutrophil count was significantly higher at 48 hours and serum calcium concentration was significantly lower at time 0 and at 48 hours in cows with severe or moderate disease, compared with cows with mild disease. Twenty-eight, 51, and 77% of cows with mild, moderate, and severe disease, respectively, had > 100,000 colony-forming units/ml of milk at time 0. The odds that a cow with severe disease would die or be culled were 3.6 times the odds for a cow with moderate disease and 11.2 times the odds for a cow with mild disease.


CONCLUSIONS
Results suggest that a classification scheme based on readily observable systemic disease signs can be used to classify disease severity in cows with acute coliform mastitis.
Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins 80523, USA.
J R
JR
Wenz
G M
GM
Barrington
F B
FB
Garry
R P
RP
Dinsmore
R J
RJ
Callan
D000208:Acute Disease; D000818:Animals; D002417:Cattle; D015331:Cohort Studies; D015169:Colony Count, Microbial / Q000662:veterinary; D004755:Enterobacteriaceae / Q000302:isolation & purification; D004756:Enterobacteriaceae Infections / Q000145:classification / Q000175:diagnosis / Q000662:veterinary*; D005260:Female; D007958:Leukocyte Count / Q000662:veterinary; D008414:Mastitis, Bovine / Q000145:classification / Q000175:diagnosis* / Q000382:microbiology; D008892:Milk / Q000382:microbiology*; D009504:Neutrophils; D011446:Prospective Studies; D012720:Severity of Illness Index; D016896:Treatment Outcome