Mastitis prevalence in primigravid heifers at parturition.
Prevalence of intramammary infection was determined for 382 primigravid heifers within 3 d postpartum on 11 Vermont dairy farms. Data collected during a 5-yr period are summarized. Duplicate quarter milk samples were cultured on tryptose-blood agar plates containing .1% esculin. Intramammary infections were diagnosed in 45.5% of the heifers and 18.7% of quarters. Staphylococcus species were the most prevalent bacteria isolated: they appeared in 25.4% of the heifers and 12.1% of quarters. Only 2.6% of the heifers were diagnosed with Staphylococcus aureus; 22.8% had udder infection caused by other staphylococcal species. Environmental mastitis pathogens, coliforms, and streptococci other than Streptococcus agalactiae were isolated from 14.9% of the heifers and 4.8% of quarters. The prevalence of mastitis among these primigravid heifers at parturition indicates a need to improve methods of diagnosis and control programs.
Pankey
J W
JW
Animal Sciences Department, Vermont Agricultural Experiment Station, The University of Vermont, Burlington 05405.
Drechsler
P A
PA
Wildman
E E
EE
D000818:Animals; D002417:Cattle; D003126:Colostrum / Q000382:microbiology; D005260:Female; D008414:Mastitis, Bovine / Q000453:epidemiology*; D007744:Obstetric Labor Complications / Q000453:epidemiology / Q000662:veterinary*; D011247:Pregnancy; D015995:Prevalence; D013203:Staphylococcal Infections / Q000453:epidemiology / Q000662:veterinary*; D013290:Streptococcal Infections / Q000453:epidemiology / Q000662:veterinary*; D014707:Vermont / Q000453:epidemiology