Docstoc

Mastitis Introduction

Document Sample
Mastitis Introduction Powered By Docstoc
					  Mastitis Pathogens

            2007



        Philip Sears
Large Animal Clinical Science
Mastitis: Intramammary Infection
               IMI
    Clinical Mastitis - Animal health
          swelling
          heat
          redness
          pain
          disturbed function
            Mastitis
           Effects on Milk

Physical appearance - color, flakes, clots, etc
pH - normal 6.5 increase to 7+
Cellularity - increase in SCC
Chloride - increase Cl-
Catalase - tissue damage - O2 release
   Mastitis Identification

If clinical mastitis is detected a
milk samples should be collected.
Culture milk on blood agar
 plates or selective media.
Coliforms
          Milk Cultures


•   Infection level in herd
•   Type of infections
•   Source of infections
•   Control and Prevention
          Milk Cultures


•   Infection level in herd
•   Type of infections
•   Source of infections
•   Control and Prevention
•   Treatment
           Milk Cultures

1. Select cows for culture (herd, HSCC, etc)
2. Collect an aseptic milk sample
3. Collect composite or quarter milk sample
4. Refrigrate (or ice) sample at collection
                 Mastitis Problem Solving
Step 1: Identify possible mastitis problems. (review records                                  )

              Clinical mastitis                         Subclinical mastitis
Severe clinical cases        New clinical cases      Bulk tank SCC           DHIA - SCC
>1% per year                 >2% per month          >250,000 cell/ml       >15% with LS>4.5

                        Quarter sample                      Composite sample

 Step 2: Use diagnostic test to determine causative organisms                             .

                           Bacteriological Cultures                    (milk)


        Environmental organisms                       Contagious organisms
              (usually clinical)                        (usually subclinical )


  Coliforms         Strep sp             Staph sp   Staph aureus               Strep ag
Mastitis: Intramammary Infection
               IMI
   Contagious mastitis
        Primary source the gland of other cows
        Major loss nonclinical - production

   Environmental mastitis
         Primary source the environment
               - soil, feces, bedding
         Major loss clinical mastitis
               - disturbed function
          Contagious Mastitis


Definition: Caused by pathogens passed from
cow to cow at milking via hands, inflations, wash
rags and other vectors
   Contagious Mastitis

Culture milk from cows & heifers:

      Streptococcus agalactiae

      Staphylococcus aureus

      Mycoplasma bovis
  Contagious Pathogens

           Big Two

• Streptococcus agalactia (Strep. ag.)
• Staphylococcus aureus (Staph. aureus)
 MacConkey Agar                      CAMP Test for
                                 Streptococcus agalactiae
Strep ag         Strep sp




                                                        Strep uberis

    Blood Agar                                      
      with esculin



                            Strep dyagalactiae
                                                        Strep agalactiae



                               enterococci




                                 Staph aureus -  hemolysin
            Strep ag Mastitis                       Strep agalactiae
          Streptococcus agalactiae

             Contagious mastitis
•   Lives only in infected quarters
•   Spread from cow to cow(milking, hands, common cloth)
•   Subclinical
•   High SCC and Reduced production
•   Treatment:
     – Lactation          60 - 95% (75%)
     – Dry off            80 - 98%
         Strep ag Susceptible
             Laboratory Testing

Active             Isolates          Susceptible
                   Tested               (%)

Amoxicillin        114/116    98.3
Pen/Novobiocin     106/108              98.1
Cephaprin          119/123    96.7
Novobiocin           80/87              92.0
Pirlimycin         108/123              87.8
Erythromycin       107/123              87.0
Hetacillin         104/123              84.6
Penicillin         94/123               80.5
         Strep ag Susceptible
           Herd Treatment - NY

Active            Cows            IMI cures
                 Treated            (%)

Amoxicillin      115/138   83.3
Hetacillin       101/131             77.1
Erythromycin     135/176             76.7
Cloxicillin      187/250             75.6
Pen/Novobiocin     22/31             71.0
Pirlimycin         37/60             62.0
Cephaprin         65/116   56.0
Penicillin          9/22             41.0
      Approved IMM Drug List
•   Amoxi-Mast- Rx
•   Masti-Clear - OTC
•   Dariclox- Rx
•   Gallimycin-36 - OTC
•   Hetacin K- Rx
•   Pirsue- Rx
•   ToDAY (Cefa-lak)- OTC
                               Sears, 2003
                                                      DCT

           Strep ag Mastitis
    TD



• Control & Prevention:
   – pre & post milking teat dipping
   – separate paper towel
   – milk infected cows last
   – dry cow treat all cows
   – screen replacements (home & purchase animals)
      • CMT, culture milk or culture bulk tank milk
      • know the history of the purchase herd
               Strep ag Mastitis
         Herd A                                 Herd B
485 cows (Strep ag-free)                   450 cows
purchase 110 cows                          purchase 450 cows
SCC 350,000 to 670,000 (2mo)               120,000 to 180,000
cultured 49 cow Strep ag                   Screened all cows
Eradicated Strep ag in 8 months            No Strep ag added

                    Finanical Loss
                                     A                B
Laboratory cost                   $6,626           $1,465
Loss milk (cow tx)                 5,265                0
Culling (cows)                    16,800            4,900
Drug cost ( Rx)                    2,100                0
Premium loss ($.25/cwt )          13,500                0
                 Total            $44,291          $6,365
                 Total/cow            $91.32         $10.61
                          Staphylococcus aureus


                                                     




          No Growth


                                 MacConkey Agar
Staph aureus          Staph sp

           

                                 Blood Agar
Staphylococcus aureus




  Gangrene mastitis
               Staph Mastitis
            Staphylococcus aureus

               Contagious mastitis
• Lives in infected quarters & infected skin
    – injured teat ends (mechanical, chemical, weather)
•   Spread from cow to cow(milking, hands, common cloth)
•   Nonclinical with high SCC & reduce production
•   Clinical (mild to severe) with repeated flare-ups
•   Treatment:
     – Lactation          15% (10 – 60)
     – Dry off            50% (40 – 70)
     – Can become “chronic”, long standing infections
                                            DCT


             Staph Mastitis
    TD



• Control & Prevention:
   – pre & post milking teat dipping
   – separate paper towel
   – milk infected cows last
   – dry cow treat all cows
   – cull cows with long standing infections (chronic)
   – screen replacements (home & purchase animals)
    Treatment of S.aureus IMI
                   Antibiotics

                   Field Studies
Product            Glands             Cures
Clox/florfenicol      33            1    3%, Wilson 1996
Amoxicillin           12            1    8%, Sears 1994
Pirlimycin            68           12 18%, Sears 1998
Total                104           14 13%

            Staphylococcus aureus isolation
              Sampling      Culture positive
                 1               75%
                 2               94%
                 3               98%
        Staphylococci Mastitis
Staph intermedius, Staph hyicus, Staph chromogenes

Source: environment - skin, bedding
        contagious ? once herd level increases

Characteristics
       colonize teat canal readily
       prevalent in well managed herds (10-15%)
       like C. bovis - TD indicator

Losses: subclinical mastitis -
       10% SCC >500,000 cells/ml
       10% clinical
         Staphylococci Mastitis
  Staph intermedius, Staph hyicus, Staph chromogenes

Control
       Postmilking teat dip
       Eliminate with dry cow therapy
                                                     TD
                                           control
Treatment
      Dry cow therapy - 90%
      Lactation - 28% (Wilson, 1993)




                                         Dry cow therapy
          Mastitis in Heifers
   Coagulase-Negative Staphylococci
• Lactating cows: highest prevalence of
  CNS during lactation occurs at calving
• CNS are part of normal skin flora
• Many infections are transient
• Estimates of infection prevalence for
  heifers at calving 2-20% of quarters
       Mycoplasma Mastitis
                Mycoplasma bovis

              Contagious mastitis
•   Lives in infected quarters, respiratory & reproductive tract
•   Spread from cow to cow (milking, nasal & vaginal discharge)
•   Subclinical; high SCC and reduce production
•   Clinical; multiple quarters (mild to severe)
     – mulitple quarters, sandy texture & tannish-color milk
     – joint infections- swollen & lame
• Treatment: none
     – nonresponsive to antibiotic treatment
        Culturing Mycoplasma


Isolated in clinical cases

Bulk tank milk is a successful monitor

Identify & segregate all positive animals
      (reculture for confirmation)
               Mycoplasma Mastitis
                                                  Mycoplasma units




• Control & Prevention:
   – pre & post milking teat dipping
   – milk infected cows last
   – cull infected cows or segregate infected cows
   – culture replacements (home & purchase animals)
      • culture bulk tanks or know herd history
       Mycoplasma bovis
     - when to be concerned
1.   mastitis following respiratory problems in herd
2.   young calf joint swelling and lameness
3.   young calf head tilt - inner ear infections
4.   new knee and hock swelling on cows
     Mycoplasma bovis
   - when to be concerned
5. multiple quarters with clinical mastitis
     non-responsive to antibiotic treatment
     off- color or watery (sandy)
     new additions to the herd
     culture negative - blood agar
       Environmental Mastitis

Primary source: soil, feces, bedding

Major loss: clinical mastitis & gland dysfunction

Culture milk:
      Coliforms; E. coli, Klebsiella sp, Enterbacter sp
      Streptococcus sp                       (Gram +)
      Staphylococcus sp                      (Gram +)
      Pseudomonas sp, Serratia, Proteus (Gram -)
                            Coliforms




 MacConkey Agar




E. coli     Klebsiella sp




    Blood Agar
                  Coliforms
                     E. coli
                  Klebsiellae sp
         Upjohn




Environmental Mastitis
• Etiology: fecal organisms
   – poor hygiene (not cow to cow)
   – higher incidence in hot summer (July-Aug)
   – bedding (Klebsiella with wood products
• Clinical mastitis
   – Acute/toxic (15% will be severe & life threating)
   – rarely chronic (Klebsiella more common)
                Coliforms
                  E. coli
               Klebsiellae sp

• Treatment: supportive
   – fluids (IV & oral)
   – NSAID (ei, Banimine-flunixin meglumine, etc)
   – antibiotic therapy of little value
• Control & Prevention
   – Clean & dry bedding
       • inorganic - sand
       • maintained and monitored
   – J-5 vaccination in dry period (3x)
  Acute Coliform Mastitis Therapy

• Antimcrobials will NOT replace a
  competent immune system!
  – selenium-vitamin E
  – concurrent metabolic disease
  – core-antigen vaccines

• Shock is the primary concern
  – Correction of tissue perfusion deficits
        Supportive Fluids

     40 to 60 L of isotonic saline
                 OR
   2 L of 7.5% saline (hypertonic)

Hypocalcemia is most consistent serum
          chemistry change
            (Replace slowly)
               Coliforms
                  E. coli
               Klebsiellae sp

• Treatment: supportive
   – fluids (IV & oral)
   – NSAID
   – antibiotic therapy of little value
• Control & Prevention
   – Clean & dry bedding
       • inorganic - sand
       • maintained and monitored
   – J-5 vaccination in dry period (3x)
    Sources                Solutions




Dirty-wet stalls         Clean & Dry
                         sand bedding




                                   Vaccinate - J5


         Repair stalls
           Streptococcus spp (environmental)
               Str. uberis, enterococci, Str. dysgalactiae




                                                        Esculin positive


  MacConkey Agar

Strep ag   Strep sp




                      Blood Agar
                      with esculin
       Streptococcus Mastitis
Str. uberis, enterococci, Str. dysgalactiae
           Environmental Mastitis
• Etiology: fecal organisms, rumen, genitalia
   – poor hygiene (not cow to cow)
   – higher incidence late dry period
   – any time during lactation
• Clinical mastitis
   – mild (<15% will be clinical )
   – usually short duration, can become chronic (ave 45 days)
• Treatment
   – Lactation         15-85%    (78% , Wilson, 1993)
   – Dry off           >75%
       Streptococcus sp susceptibility
                93 isolates
                       Sensitive   Resistant

Pencillin/Novobiocin     98%          2%
Cephalothin              97%          3%
Erythromycin             83%         17%
Penicillin               76%         24%
Ampicillin               74%         26%
Pirlmycin                53%         47%
Tetracycline             23%         77%
Cloxacillin              14%         86%
Efficacy for Gram-Positive Pathogens

Pathogen           # qrts treatment   % cure

Staph aureus        121    ND         24.8
Strep agalactiae     31    ND         51.6
other Streps        111    ND         36.0

Staph aureus       1141    Clox       26
Strep agalactiae    762    Clox       85
Strep uberis        797    Clox       77
                                      Craven, 1991
   Antimicrobials and mild mastitis

• No antimicrobial use increased SCC,
  prevalence of Strep uberis




                           Cattell, 1996
     Streptococcus Mastitis
Str. uberis, enterococci, Str. dysgalactiae

   • Control & Prevention
       – premilking sanitation - Teat Dipping
       – clean & dry: housing & bedding
       – dry cows management
          • close up & maternity pens
          • clean dry bedding
           Bulk Tank SCC (Herd)

           DHI Monthly SCC (Cows)

         CMT Cows at LS 4 and Above

               Positive Quarter(s)

                       Culture

Contagious Organism              Environmental

     Segregate             1. Clean up environment
                           2. Do not have to segregate
  1. Milk separately       3. Watch closely
  2. Sell                  4. Treat Appropriately
  3. Dry off                     a. Feed intake
                                 b. Activity
          Serratia spp

• Etiology: common soil & plant inhabit
   – poor hygiene & wet areas
   – resistant in chlorhexidine gluconate teat dips
   – greater incidence from dry period
• Clinical mastitis
   – mild
   – chronic lasting several lactations
   – nonresponsive to therapy
• Control
                                                         Use iodine TD
   – check teat dip & environmental sanitation
   – E. coli J5 vaccine to reduce incidence & severity
    Pseudomonas spp
• Etiology: water & wet bedding
   –   poor hygiene & wet areas
   –   resistant in chlorhexidine gluconate teat dips
   –   low level iodine in drop hoses
   –   contaminated water system (hot water heaters)
• Clinical mastitis
   – chronic infection
   – nonresponsive to therapy
• Control
   – check teat dip & environmental sanitation
   – sand bedding
   – E. coli J5 vaccine to reduce incidence & severity
          Corynebacterium bovis
          (differ from Arcanbacterium pyogenes)
Source:
       Infected glands & teat canal

Effect:
       Colonizes ductal tissue easily
       Mild - low SCC <300,000
       Chronic (good indicator organisms for TD practices)
Control:
       Postmilking teat dip
       Dry cow therapy - eleminated in dry period
 Corynebacterium
(Arcanbacterium pyogenes)
Source:
        Infections; wounds, teat injuries, abscesses
        “summer mastitis” humid weather
        calving area - transmitted by flies
Diagnosis:
        differs from C. bovis - very hemolytic on BA
Effect:
        Destroys quarter - purlent
        Chronic - high SCC
        Risk to other cows
Control:
        No treatment - kill quarter
        Maintain calving area - clean & dry
        Prognosis is poor
   Yeast/Nocardia
   (Opportunistic pathogen)
Source:
       Soil
       Contaminate medication & mixtures
       Prolonged antibiotic use (contamination)
Effect:
       Chronic mastitis (destroys gland)
       Self-limiting
Control:
       Use commerical products
       Use aseptic infusion
        Distribution of Clinical Mastitis
          S. aureus
                    E. coli                  Strep
             4.7%                                          E. coli
    Strep            16%                      8%
                              Kleb                          12%
    10.2%                      6%
                                     Staph                           Kleb
                                      11%                             4%
Staph
7.5%


                 Neg                                 Neg
                 53%                                 55%




            dD Farms                           GM Farms
                                  Clinical Mastitis Treatment Protocol
                                                                    Clinical
                                                                    Mastitis
                                                                     Cow




              Boxstall                                                                                          Mastitis Pen
            1. NSAID                         Fever                  Physical               No Fever            1. Await Culture
                                                                     Exam
            2. Oral Fluids                                                                                     2. Monitor
            3. Monitor



                                                                     Culture
                         20% Gram-positive                                                   80% Coliform/no growth
                         Antibiotic treatment                                                    No antibiotics


         Strep Ag           Staph aureus             CNS Staph            Envir Strep           Coliform         No Growth
      Intramammary          Intramammary                                                     No Antibiotics     No Antibiotics
                                                 Intramammary           Intramammary
20%      antibiotic            antibiotics
                                                    antibiotics            antibiotic
                                                                                              NSAID, if          NSAID, if        80%
      Treat all 4 qrts       Flag records                                                        Fever              Fever
Tx     Flag records               Cull?
                                                  Flag records              therapy
                                                                                                Monitor            Monitor        NT


                          Quarter loss to                                                          Remove cow
                                                     3 Quarters      Outcome        Cull
                           production                                                                   Cull

                                                                  Return to Herd


                                                                  Return to Herd
                                                                       Milk
                                                                                                                         Hess, 2003

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:7
posted:10/25/2012
language:English
pages:57