The Mastitis Lab in Private
Practice
Brenda Moslock Carter, DVM
Keseca Veterinary Clinic, PLLC
P.O. Box 267, 1441 State Routes 5 & 20
Geneva, NY 14456
keseca@rochester.rr.com
Keseca’s in-house
mastitis lab
• Started in 2004
• Currently 2
technicians
• Average ~450
cults/month
(> 100/week)
• Regularly participate
in Lab Proficiency
Program (QMPS)
Laboratory Services
• Individual cow cultures
– Clinical & subclinical (High SCC) cows
– Aerobic cultures
+/- Mycoplasma (can refer out)
• Bulk tank cultures
– Regular monitoring (screening for
contagious bugs)
– Quantitative analysis (trouble-shooting
high bacterial counts)
Laboratory Services (contin’d)
• Bedding cultures
– Troubleshooting environmental mastitis
• Towel cultures
– Troubleshooting or routine monitoring
• Colostrum & pasteurized waste milk
– Monitoring hygiene +/- pasteurizer fnct
– Troubleshooting calf health problems
Quantitative analysis (“bacterial counts”)
Keys to success with inhouse mastitis culturing
• Rapid turnaround & reporting of
results (next-day preliminaries)
• Dedicated person in charge
• Provide “value added service”
(specific treatment recommendations,
consultation/ follow-up, monthly
summaries for large herds, etc.)
Provide a value-added service
Guidelines for Submission of Milk Samples to Keseca
Veterinary Clinic’s Mastitis Lab & New Client Questionnaire
1.
Call in for milk sample pick-up between 7:30am – 9:00am, Mon-Fri for same-day pickup. 315-781-1378. For next day results on samples collected after 9am, you must
deliver them to the clinic by 3:30pm.
2. Preliminary results are reported 6 days/wk, Mon-Sat, (excluding holidays) on the
day after the sample is received. Treatment recommendations will accompany the
Prelims. Final results are read at 48hrs and only changes from prelims are reported
directly. Final results will be uploaded to the LOOP and will appear in your cowfile
when you download from DairyOne, however there may be a significant lag time
before these appear.
3. We try to report your results in time to accommodate your treatment schedule, and
can usually do this successfully during normal workdays, Mon-Fri. Saturday results
are reported by the doctor on-call, and the time will vary. (rarely, not until Sunday)
Primary contact :_________________________________ Phone______________
Secondary contact:__________________________ Phone__________________
Preferred method for receiving prelim results:
Phone___________________
Fax____________________
Email___________________
CC_____________________
Do you want a hard copy of the final results (In addition to the automatic entry as a
CULTURE event into DairyComp via downloads from the LOOP)? Yes / No
If yes, how?____________________________________
What time do you treat the hospital cows? __________________
Will this be a DropBox herd? Yes / No
Herds are also given a sheet of personalized
labels to put on sample vials
Individual cow samples
Composite
samples
Only exceptions
1. Screening for
mycoplasma or
prototheca
2. Post-tx sample of
Staph aureus cow
Only exceptions: screening for Myco or Prototheca
-or- post-treatment Staph aureus screening
So what do we need to
start up a mastitis lab in
our clinic?
Necessary Equipment
• Incubator @ 37o C
•
•
•
•
•
+/- another @ 32o C for bulk tank cultures
Bunsen burner or little propane torch
Refrigerator for storing plates
Freezer for storing samples
Microscope
Fluorescent & incandescent light
sources
Incubator
• 37o (+/- 32o)
• Desktop model
– Holds up to ~50
plates + tube rack
– Used models < $100
• Check local dealers
for used hospital
equipment
• Desktop incubator @ 37o C (~ $100 used)
• Little propane torch ($45)
Refrigerator/freezer
Microscope
• Fluorescent & incandescent light
sources ($15 each)
Total capital investment < $200
(Assuming clinic already has a fridge/freezer and microscope)
Necessary Supplies
•
•
•
•
•
Sterile cotton swabs (or disposable loops)
Wire loops (10uL)
Disposable sterile plastic 1ml pipettes
Microscope slides
+/- Graduated pipettes (if doing
bacterial counts)
• Tube rack
Basic Media & Reagents
for NMC Method
•
•
•
•
•
•
•
Blood agar plates
MacConkey plates
Coagulase tubes
Broth tubes
Gram staining kit
Hydrogen Peroxide
Potassium Hydroxide
Misc.
• System for tracking samples,
recording & reporting results
• NMC Handbook, other reference
manuals
• Good relationship with your local
referral lab
– Training
– Phone support
– Diagnostic support
Culture
®
Tracker
software
• Developed by Dairy One in NY
• Generates worksheet for lab techs
• Final result sheet for client also
shows cow’s prior culture history
• Data can be exported to Excel for
analysis
Results come with the cow’s
history of previous cultures
• Easy to identify
chronic cows
• If repeat quarter: is
it the same bacteria
(treatment failure) or
a new infection?
• Follow-up on Staph
aureus cows
Previous culture
results
Current culture
result
Culture
®
Tracker
software
• Results interface with Dairy Comp via
Dairy One (uploaded to the LOOP)
• Farm’s computer can be set to
automatically download new results daily
• Results automatically recorded in Dairy
Comp or Scout
Results recorded in a consistent manner
Initial cost ~$250
Annual fee ~$275
Diagnostic Flowchart
“Strep species ”
(i.e. “Strep non-ag”)
• Strep dysgalactia (Strep dys)
• Strep uberis
• Lactococcus sp.
– Lactococcus lactis
• Aerococcus sp.
• Enterococcus sp.
May explain differences in response to treatment of “Strep species”
Strep Diagnosed
- KOH neg, Catalase neg,
Gram pos cocci
Differentiating
Strep species
Hemolysis?
Wide
Narrow
Strep canis
- confirm with CAMP
test
Grp G Antibody
None
Strep ag
- confirm with CAMP
test
Grp B Antibody
Negative
Or
Dubious
Esculin
Splitting?
Positive
Growth on
Enterococcosel
media?
Strep dys
- confirm with Grp C
Antibody
(“PathoDx C”)
Yes
No
Strep uberis
“Strep other”
- Enterococcus
- Lactococcus
- Aerococcus
Takes an
additional day
“Esculin-Splitting”
black light-vs-fluorescent light views
(same 2 plates)
black light
Only 1 isolate is positive
for “esculin-splitting”
(gray/black-tint)
standard lighting
3 out of 4 isolates
“esculin-positive”
(greenish-tint)
Mycoplasma Culturing
• Requires special media & incubation
conditions (CO2 incubator)
• Can be tricky to read (up to 7 days)
• Whether or not you offer may
depend upon prevalence in your area
Alternative approach to Mycoplasma surveillance =
referring out for pooled cultures
Pooling for Mycoplasma
Surveillance
Pros
• Referral lab better
equipped to handle, esp
if in low-prevalence area
• Cost-effective way to
increase myco
surveillance
• May find it before it
shows up in Bulk Tank
cultures
Cons
• Myco susceptible to
repeated freeze-thaw
cycles & prolonged
storage
– May get more false-negs
in low-cfu samples
• Delayed turnaround if
pool is pos
– Need to wait for
individual samples to be
run
• May not be available in
all areas
Of the cases we culture in
our practice:
• ~1/3 are considered
treatable
Overall, we recommend treatment for
• ~1/3
onlyare
~50%sometimes
of the clinical cases we culture
treatable
Coliforms
– (based on cow’s history
& severity / amount of
bacteria)
• ~1/3 should not be
treated
– (sometimes because the
bacteria are already
gone!)
Staph aureus
Staph species
Streps
Staph species
Yeast
Prototheca
Mycoplasma
No Growth
Treatment Recommendations
Intramammary Antibiotics: to Treat or not to Treat?
Generally Treat
Sometimes Treat
Never Treat
Strep ag
Staph aureus*
A pyo
(Extended therapy)
Strep dysgalactia
Staph species (CNS
Yeast
Staph)
Strep uberis*
Coliforms
Mycoplasma
(Extended therapy)
Influencing factors:
- Chronicity (based upon SCC hx)
- #cfu
Prototheca
“No growth” or “NSO”
The cost of over-treating: an
extreme example
this herd not only treated every clinical case, but
they kept cows in treated group until CMT improved
2006
2005
2004
2003
2002
2001
6.0
4.0
2.0
0.0
2000
Avg Lbs/cow/day dumped
Avg Lbs/cow/day dumped
The dairy SOLD more
milk/cow in 2006 despite
producing ~2lbs less per
cow than in 2005
Cost of dumped milk
$ 140, 000. 00
$ 120, 000. 00
$ 100, 000. 00
$ 80, 000. 00
$ 60, 000. 00
$ 40, 000. 00
$ 20, 000. 00
$2000
2001
2002
2003
V al ue of dumped mi l k @$ 12. 50/ cwt
2004
2005
2006
A ct ual val ue of dumped mi l k based on mai l box pr i ce