Herd-level prevalence of Mycoplasma spp mastitis and characteristics of infected dairy herds in Utah as determined by a statewide survey.
OBJECTIVE
To determine herd-level prevalence of Mycoplasma spp mastitis in Utah dairy herds and characterize farms and management practices for positive herds.


METHODS
Epidemiologic study.


METHODS
Bulk tank milk samples from 222 of 285 (78%) dairy farms in Utah.


METHODS
Milk haulers or dairy producers collected 5 milk samples from all bulk tanks at 3- to 4-day intervals for mycoplasmal culture. Owners of all positive herds were offered follow-up visits.


RESULTS
Milk samples from 16 of 222 (7%) herds had positive mycoplasmal culture results. Follow-up information was obtained from 14 of 16 herds; 12 provided complete data. Some characteristics of mycoplasma-positive herds included the following: 8 of 14 herds had > 750 lactating cows, 9 of 11 had bulk tank milk somatic cell count of 140,000 to 240,000 cells/mL, 7 of 11 had actual milk production of 9,535 to 11,622 kg (21,000 to 25,600 lb)/305 d, 11 of 12 had cows with clinical mastitis that was nonresponsive to treatment and involved >or= 2 mammary gland quarters, 9 of 12 had cows with clinical mastitis that spread from 1 mammary gland quarter to another, 8 of 12 had cows with droopy ears, 7 of 12 had cows with a head tilt, 7 of 12 used common milking towels, 2 of 12 were closed to replacement cattle for > 1 year, and 2 of 12 purchased bulls only.


CONCLUSIONS
Herd-level prevalence of mycoplasma mastitis in Utah was relatively high, compared with other areas of the United States.
Wilson
David J
DJ
Department of Animal, Dairy and Veterinary Sciences, College of Agriculture, Utah State University, Logan, UT 84321, USA.
Goodell
Greg
G
Justice-Allen
Anne
A
Smith
Scott T
ST
D000818:Animals; D002417:Cattle; D003612:Dairying; D005260:Female; D008297:Male; D008414:Mastitis, Bovine / Q000453:epidemiology / Q000382:microbiology* / Q000517:prevention & control; D009175:Mycoplasma Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D015995:Prevalence; D014589:Utah / Q000453:epidemiology