Reference Guide for Mastitis-Causing Bacteria
ID
404-230 (DASC-213P)
EXPERT REVIEWED
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Information obtained from NMC Laboratory Handbook on Bovine Mastitis and veterinary consultation for treatment recommendations.
Classification | Bacteria1 | Contagious or Environmental | Source | Spread | Prevention and Control | Treatment2 |
Staphylococcus spp. | Contagious | Infected udders, hands of milkers | Milking time | Postdip, DCT3, | Chronic infections: low treatment efficacy, culling. | |
Staphylococcus spp. | Neither | Skin flora and occasionally environment | Infect teat canal from skin sources | Postdip, DCT | IMM therapy labeled products | |
Streptococcus spp. and | Contagious | Infected udders | Milking time | Milking-time hygiene, postdip, DCT | IMM therapy labeled products | |
Streptococcus spp. and | Contagious and environmental | Infected udders and environment | Milking time and environmental contact | Milking-time hygiene, | IMM therapy labeled products | |
Streptococcus spp. and | Environmental | Environment: | New IMI5 during early dry period | Milking-time hygiene, | IMM therapy labeled products | |
Streptococcus spp. and | Environmental | Environment | Environmental contact | Milking-time hygiene, | IMM therapy labeled products | |
Coliform |
Environmental
| Bedding, manure, soil | Environmental contact | Cows clean and dry, use of sand bedding, predip, J5 vaccine | Do not treat local cases; manual stripping of affected | |
Coliform | Environmental | Organic bedding | Environmental contact | Avoid sawdust and recycled manure, predip, J5 vaccine | Do not treat local cases; manual stripping of affected | |
Coliform | Environmental | Bedding, manure, soil | Environmental contact | Cows clean and dry, use of sand bedding, predip, J5 vaccine | Do not treat local cases; manual stripping of affected | |
Coliform | Environmental | Soil and plants | Environmental contact | Cows clean and dry, predip | Low treatment efficacy, culling | |
Coliform | Environmental | Water and wet bedding | Environmental contact | No water use in parlor, no cooling ponds, sand bedding, J5 vaccine | Low treatment efficacy, culling | |
Coliform | Environmental | Bedding, feed, water | Environmental contact | Not much known, use of | Low treatment efficacy, culling | |
Coliform | Probably contagious | Upper respiratory tract of mammals and birds | Unknown: likely cow to cow | Prevent teat injuries, | Low treatment efficacy, culling | |
Other | Environmental | Soil, plants, water | Dirty infusions | Aseptic infusions | No treatment, culling | |
Other | Contagious | Infected udders | Cow to cow | Postdip | Treat prior to dry-off with IMM labeled products | |
Other | Environmental | Soil, plants, water | Dirty infusions, infected udders | Aseptic infusions, | No treatment, culling | |
Other | Environmental | Soil, water, air | Dirty infusions | Aseptic infusions | IMM therapy labeled products | |
Other | Environmental | Teat injuries | Flies | Fly control | Established infections: low treatment efficacy, dry off quarter. New infections: IMM therapy labeled products or 4-5 days injectable broad-spectrum antimicrobial (penicillin6, | |
Other | Contagious | Milking time | Respiratory or urogenital tract to udder | Milking time hygiene, | No treatment, culling |
- Click on the name of each bacteria for more information.
- These are general treatment recommendations: actual recommendations may vary from herd to herd. Please consult your veterinarian.
- DCT = dry cow therapy
- IMM = intramammary
- IMI = intramammary infection
- Extra-label usage if systemic treatment given for more than 2 days; consult your veterinarian.
- Extra-label usage; consult your veterinarian.
- Signs of systemic mastitis include hypothermia, fever, down cow, and purple color of the udder. Treatment options may include an injectable broad-spectrum antimicrobial (penicillin, ceftiofur, ampicillin, oxytetracycline), non-steroidal anti-inflammatory drugs, IV fluids, oral fluids, oral calcium, magnesium, and phosphorus solutions/powders.
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Publication Date
August 3, 2026
