title: Intramammary infections in heifers during early lactation following intramammary infusion of pirlimycin hydrochloride or penicillin-novobiocin at the first milking after parturition.
abstract: A study was conducted to determine whether intramammary antibiotic treatment of heifer mammary glands following the first milking after calving was effective for reducing the percentage of mammary quarters infected during early lactation. Jersey and Holstein heifers from two research herds were assigned to one of three treatment groups: (1) no intramammary infusion following the first milking after parturition, (2) intramammary infusion of all quarters with pirlimycin hydrochloride following the first milking after parturition and (3) intramammary infusion of all quarters with novobiocin sodium plus penicillin G procaine following the first milking after parturition. Almost 93% of Jersey heifers (40/43) and 73.1% of quarters (125/171) were infected at the first milking. Almost 77% of quarters (33/43) were cured following treatment with pirlimycin, 61.8% (21/34) were cured following treatment with penicillin-novobiocin and 39.6% (19/48) of infections were eliminated spontaneously in the untreated control group. Significantly fewer infections were observed in pirlimycin or penicillin-novobiocin treated mammary glands of Jersey heifers during early lactation than in untreated control mammary glands. Almost 89% of Holstein heifers (32/36) and 52.8% of quarters (76/144) were infected at the first milking. About 57% (12/21) of quarters were cured following treatment with pirlimycin, 41.4% (12/29) were cured following treatment with penicillin-novobiocin and 23.1% (6/26) of infections were eliminated spontaneously in the untreated negative control group. Significantly fewer infections were observed in pirlimycin treated mammary glands of Holstein heifers during early lactation than in untreated control mammary glands. However, no significant differences were observed following penicillin-novobiocin treatment of Holstein heifers after the first milking of lactation compared with untreated control quarters. Coagulase-negative staphylococci, Streptococcus uberis and Streptococcus dysgalactiae subsp dysgalactiae were isolated most frequently in heifers from both herds.
authors.affiliation: Department of Animal Science and Food Safety Center of Excellence, Institute of Agriculture, The University of Tennessee, Knoxville 37996, USA. soliver@utk.edu
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Oliver
authors.forename: Susan I
authors.initials: SI
authors.lastname: Headrick
authors.forename: Barbara E
authors.initials: BE
authors.lastname: Gillespie
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Lewis
authors.forename: David L
authors.initials: DL
authors.lastname: Johnson
authors.forename: Kenneth C
authors.initials: KC
authors.lastname: Lamar
authors.forename: Hugh
authors.initials: H
authors.lastname: Moorehead
authors.forename: Henry H
authors.initials: HH
authors.lastname: Dowlen
authors.forename: John W
authors.initials: JW
authors.lastname: Hallberg
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000627:therapeutic use; D001424:Bacterial Infections / Q000517:prevention & control / Q000662:veterinary*; D002417:Cattle; D002418:Cattle Diseases / Q000382:microbiology* / Q000517:prevention & control*; D002981:Clindamycin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D005260:Female; D007263:Infusions, Parenteral; D008321:Mammary Glands, Animal / Q000382:microbiology* / Q000473:pathology*; D008892:Milk / Q000187:drug effects / Q000382:microbiology*; D009675:Novobiocin / Q000008:administration & dosage / Q000627:therapeutic use*; D036801:Parturition; D010406:Penicillins / Q000008:administration & dosage / Q000627:therapeutic use*; D011247:Pregnancy
chemical_list: D000900:Anti-Bacterial Agents; D010406:Penicillins; D009675:Novobiocin; D002981:Clindamycin; C034093:pirlimycin