2012 Indiana Regional Dairy Meetings. Purdue University College of Veterinary Medicine Dr. Jon Townsend Dairy Production Medicine

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1 2012 Indiana Regional Dairy Meetings Purdue University College of Veterinary Medicine Dr. Jon Townsend Dairy Production Medicine

2 Focusing on the selection of the correct animals, diagnosis of causative pathogens and administration of treatments for appropriate durations can help improve the outcomes of mastitis treatments

3 Clinical or Subclinical Infection

4 Characterized by abnormal milk (flakes, clumps) Swollen/inflamed quarter Systemically ill cow

5 Characterized by normal appearing milk Has an elevated Somatic Cell Count >200,000 cells/ml is traditional determination of infection

6 What Bug Is It?

7 Contagious Staph. aureus Strep. agalactiae Mycoplasma bovis Corynebacterium bovis Environmental/Opportunist Strep non-ag (ex. uberis) E.coli Klebsiella Coagulase neg. Staph Yeast Pseudomonas

8 Invasive pathogen that produces fibrosis and abscesses/microabscesses Approximately 20% of infections become clinical Major cause of subclinical mastitis Bulk tank SCC is often elevated May be difficult to diagnose

9 Low lactational antibiotic cure rates (10-30%) Antibiotic cure rates during dry period range from 50 to 80% May be resistant to penicillin

10 Not invasive Causes inflammation and fibrosis Clinical cases are usually mild Primarily a cause of subclinical mastitis Bulk tank SCC s are usually significantly elevated Easy to culture

11 Sensitive to penicillins Lactational and dry cow antibiotic therapy both have cure rates > 90% Easily eradicated through antibiotic therapy and teat dipping

12 Characterized by multiple quarter involvement with clinical mastitis Clinical cases usually severe with significant change in milk appearance Often associated with a systemic phase of infection Requires special media for culture

13 Treatment seems to be of little benefit Segregate and cull when possible Prevention depends on adherence to accepted contagious mastitis control protocols

14 Minor contagious mastitis pathogen Can be easily found on bulk tank cultures Susceptible to most antibiotics RED FLAG for poor teat dipping and dry cow treatment programs

15 CONTROL Maintain closed herd Milk infected cows last Backflush Milking equipment maintenance

16 CONTROL Proper udder prep (clean,dry) Proper milking technique Proper teat dipping Dry cow therapy Cull chronically infected cows

17 Manifested as acute clinical cases Udder is often firm and swollen Milk is usually serous or hemorrhagic with clots Majority of cases in early lactation Clinical signs mainly caused by endotoxins Systemic illness due to toxemia may occur

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19 Will not normally cause persistently elevated bulk tank somatic cell counts Herd monitoring accomplished by culturing milk from new clinical cases Large percentage of milk cultures may be negative

20 PREVENTION Need to prevent, not treat Sanitation Milk clean, dry udder Vaccination

21 Organisms commonly found on skin and mucous membranes Strep. dysgalactiae often found in reproductive tract fluids Strep. uberis is found in rumen contents and survives well in soil

22 Approximately 50% of infections become mild clinical cases Highest rate of infection occurs during dry period During lactation, majority of cases occur in early lactation

23 Herd monitoring best accomplished by culturing high SCC cows and clinical cases Lactational therapy ~50-60% cure Dry cow therapy eliminates majority of existing infections

24 Coagulase negative Staphs Usually transient, mild Contaminated sample? Arcanobacter pyogenes Nocardia, Candida,Yeasts Pseudomonas Serratia Gram - soil organism Bacillus

25 *Dry Off* * Calving* * Entire Lactation* CMT or Culture ~60 days Lactation 300+ days Dry Fresh 15-30% (Average) <10% is the goal New infections at fresh 10-15% new infections per month. (Average) <5% is the goal

26 Linear Score < 5.0 Lactation 1: > 90% Lactation 2: > 85% Lactation 3+: > 80% Whole herd: > 85% Linear Score > 7.0 Lactation 1: < 2% Lactation 2: < 4% Lactation 3+: < 5% Whole Herd: < 4%

27 Prep teat Wipe teat end with alcohol pad (but not too much!) Strip a few squirts Tube horizontal Milk 2-3 squirts of milk into tube Cap and refrigerate

28 Can result in reduced antibiotic usage & less discarded milk Identify specific person to do culturing Accuracy will depend on milk sampling Can be done on farm Work with your veterinarian Mycoplasma may be difficult in OFC

29 Do I Treat It?

30 Clinical Mastitis Treatment Protocol Clinical Mastitis Cow Boxstall 1. Banamine 2. Oral Fluics 3. Monitor Fever Physical Exam No Fever Mastitis Pen 1. Await Culture 2. Monitor Culture Strep ag Staph aureus Staph sp Envir Strep Coliform No Growth Intramammary Antibiotic Therapy All 4 Quarters Flag in records Intramammary Antibiotic Therapy Flag in records Cull? Intramammary Antibiotic Therapy Flag in records Cull? Intramammary Antibiotic Therapy No Antibiotics Banamine if Fever Monitor No Antibiotics Banamine if Fever Monitor Lost Quarter Outcome Culled Cow Return to Herd Milk Hess J, Neuder L, Sears P, NMC 2003

31 Michigan State University Observations Treatment withheld for 24 hours did not adversely affect most cows Many clinical cases had resolved No growth/gram negative quarters did not require treatment Cows with no growth that were treated did not return to normal milk quicker or have fewer lost quarters

32 Historically have not treated subclinical cases Exception: Strep. agalactiae If treating, must know organism! Chronic cases more difficult to treat Often have better success earlier in lactation Must consider uses for discard milk

33 Discuss extended therapy with your veterinarian Pirsue, Spectramast May be beneficial for some bacteria Staph. aureus Environmental Streps.

34 TREATMENT Frequent stripping Fluids - I.V. and Oral NSAIDS Corticosteroids +/- Intramammary Antibiotics +/- Systemic Antibiotics Calcium therapy

35 Dry cow therapy Clean environment Proper udder prep (clean, dry) Identify contagious mastitis cows Cull chronic cows Work with veterinarian on mastitis plan

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