BULK TANK MILK ANALYSIS - A Tool for Troubleshooting Mastitis and Milk Quality Problems in Dairy Herds Bhushan Jayarao, MVSc, PhD, MPH David Wolfgang, VMD, AABVP Ernest Hovingh, DVM Department of Veterinary and Biomedical Sciences The Pennsylvania State University

MAC Conference May 23, 2006

MAC Conference May 23, 2006 Introduction  To assure milk quality ----bulk tank milk periodically tested for Antibiotic residues Total number of bacteria Somatic cells

MAC Conference May 23, 2006 Why is BTM analysis attractive ?  Provides a view of current and potential problems in a herd  Less expensive than quarter milk sampling the whole herd  Less time to obtain results  Rationale approach to troubleshoot herd with multiple milk quality and mastitis related problems  A new approach to managing udder health !!!!!!!!

MAC Conference May 23, 2006 Limitations of BTM analysis ?  Cannot extrapolate information to individual cow level.  For interpretation of results, 3 or more BTM samples required.  Information on herd management practices needed to interpret results  Samples must be held at 4 o C and analyzed within 36 h of collection  Proper sample collection.  Interpretation more challenging on large herds.

Bulk Tank Milk Analysis: FUNDAMENTALS

MAC Conference May 23, 2006 A systematic approach to analyzing BTM to assess raw milk quality and herd udder health  ONE  Identify the issue  Milk Quality?  Low or no premiums due to high bacterial counts  Trouble shoot persistent high bacterial counts  Monitor herd health after expansion  Education of milkers Aug Sep Oct Nov Total bacteria X 1000

MAC Conference May 23, 2006  Identify the issue  Mastitis?  Consistently high SPC >20,000 ?  BTSCC > 200,000 ?  Increased incidence of clinical mastitis ?  Troubleshoot high counts ?  Buying a whole herd ?  Low or no premiums ?  Monitor after herd expansion ?  Suspect Mycoplasma in herd ? A systematic approach to analyzing BTM to assess raw milk quality and herd udder health

MAC Conference May 23, 2006  TWO  When to collect ?  After 1-2 h of milking  Milk should preferably represent one milking

MAC Conference May 23, 2006 Select the right containers for shipping bulk tank milk No ! Nein ! Nem ! Nyet ! YES !

MAC Conference May 23, 2006  THREE  BTM samples  Agitate milk for 10 minutes  Collect 2 ounces of milk from the top of the bulk tank using a clean sanitized dipper  Note temp on the bulk tank  Label the sample  Transport sample on ice  Sampling frequency  High: 1 sample/ day for 4 days  Medium: 3 samples/ week for 2- 4 weeks  Low: 1 sample/ week for 4-8 weeks

What’s wrong with these pictures ??? No ! Nein ! Nem ! Nyet !

MAC Conference May 23, 2006  FOUR  How to ship samples ?  For Mastitis Pathogens  Freeze samples  For Bulk Tank Somatic Cell Count  Samples must be shipped on ice containing the appropriate preservative  For Mastitis pathogens and Somatic Cells  Samples must be shipped on ice  For Milk Quality  DO NOT send samples frozen. Samples must be shipped on ice  Why ?  Frozen samples do not give an accurate picture of bacterial counts

MAC Conference May 23, 2006  FIVE  Somatic Cell Count  Mastitis pathogens  Staphylococcus aureus  Streptococcus agalactiae  Mycoplasma  Coagulase negative Staphylococci  Environmental Streptococci  Coliforms  Gram-negative non-coliform bacteria  Milk quality tests  Standard Plate Count  Preliminary Incubation Count  Laboratory Pasteurization Count  Coliform Count

MAC Conference May 23, 2006  SIX  Somatic Cells  Validated flow cytometric technique  DHIA or similar facility  Mastitis Pathogens  NMC recommended protocols  State Diagnostic Laboratories  Private Laboratories  Bacteriological Quality of Milk  American Public Health Association (SMEDP)  Milk Cooperative testing facilities  State Diagnostic Laboratories  Private Laboratories

MAC Conference May 23, 2006 Suggested guidelines for monitoring BTM CountsIdeal Bulk Tank Somatic Cell Count (BTSCC)<200,000 cells/ml Standard Plate Count (SPC)<5,000 cfu/ml Preliminary Incubation Count (PIC)<10,000 cfu/ml Laboratory Pasteurization Count (LPC)<100 cfu/ml Staphylococcus aureus (SA)Not detected (0/4) Streptococcus agalactiae (SAG)Not detected (0/4) MycoplasmaNot detected (0/4) Coagulase Negative Staphylococci (CNS)<500 cfu/ml Streptococci (SSLO)<500 cfu/ml Coliforms (CC)<50 cfu/ml Non-coliforms (NC)<200 cfu/ml

MAC Conference May 23, 2006 Somatic Cells SCCCount ideal200,000 4/1141,000 4/4225,000 4/8173,000 4/12325,000

MAC Conference May 23, 2006 BTSCC and Production Loss Somatic Cell CountMilk Production Loss (%) 100, , , , , , , , , ,000,00018

MAC Conference May 23, 2006 Contagious Mastitis Pathogens S.aureusStrep.ag.Mycoplasma ideal0/4 4/ / / /

MAC Conference May 23, 2006 Contagious mastitis pathogens  Type of herd  closed herd, suggests presence of chronic infection  open herd, suggests both the likelihood of newly purchased animals bringing in the infection and chronically infected cows.  BTSCC  High Staph. aureus isolation rate (3/4), BTSCC generally ranges from 350, ,000 cells/ ml (most occasions 500, ,000 cells/ml).  High Strep. agalactiae isolation rate (3/4), BTSCC generally ranges from 500, ,000 cells/ml.  High Mycoplasma isolation rate (3/4), BTSCC variable (200, ,000 cells/ml).

MAC Conference May 23, 2006 Environmental Mastitis Pathogens CNSSSLOColiformsNon-coliforms Ideal<500 <50<200 4/ / / /124801,000020

MAC Conference May 23, 2006 Environmental Mastitis Pathogens  BTSCC:  Streptococci and Strep-like organisms: 250, ,000 cells/ml.  CNS: 350, ,000 cells/ml  Coliforms: <300,000 cells/ml  Non-coliforms: No data  Milking Procedures:  No established milking protocol  Milking procedures not consistent ( varies from milker to milker and shift to shift )  Poor udder surface (clipping or flaming not done)  Teat and teat ends not thoroughly cleaned  Milking done on wet teats, or cloth towels reused without cleaning  Farm Hygiene  Poor bedding or alley/ manure management

Rating based on cfu/ml Good Acceptable Concern (low) (medium) ( high) 10,000 Standard Plate Count  SPC of <1000 cfu /ml is an indication that milk is from clean and healthy cows  SPC of less than 5000 cfu/ml can be achieved  SPC of <10,000 can be achieved by most farms

MAC Conference May 23, 2006 Standard Plate Count SPCCount ideal<10,000 4/11,320 4/429,040 4/87,360 4/121,040 Failure of water heater New Milkers

MAC Conference May 23, 2006  Improper cleaning  Strep. agalactiae mastitis  Cows with soiled udders and teats, dirty equipment  New milkers?  Inability to cool milk rapidly to less than 4.4 C (40 o F)  Failure of water heater  Failure in sanitation  Residual water in the lines  Extremely wet and humid weather/ milking conditions Most probable reasons for high SPC

Rating based on cfu/ml Good Acceptable Concern (low) (medium) ( high) 20,000 Preliminary Incubation Count

MAC Conference May 23, 2006 Preliminary Incubation Count PICCount ideal<10,000 4/11,600 4/464,000 4/814,800 4/122,000 Failure of water heater New Milkers

MAC Conference May 23, 2006 High PICs  A high PIC count suggests:  Cleaning and sanitation of the milking system  Poor udder preparation before milking  Failure to cool milk rapidly  Prolonged storage times  Milking cows with wet teats and teat ends  Extremely wet and humid conditions Persistently high PIC counts may require identifying the organism

Rating based on cfu/ml Good Acceptable Concern (low) (medium) ( high) 200 Unclean milking equipment ? High LPC is most often seen with persistent cleaning problems Faulty milking machine or worn out parts ? Leaky pumps, deteriorated pipe line gaskets, inflations and other rubber parts, and milkstone deposits Extremely dirty cows ? Significant levels of contamination from soiled cows can also contribute to high LPC LPC

MAC Conference May 23, 2006 Laboratory Pasteurization Count LPCCount ideal<100 4/110 4/420 4/80 4/120

Rating based on cfu/ml Good Acceptable Concern (low) (medium) ( high) 50 Coliform counts >50 cfu/ml suggest: 1. Poor milking practices 2. Dirty equipment 3. Contaminated water 4. Dirty milking facilities 5.Cows with mastitis? 6.Manure? Coliforms

MAC Conference May 23, 2006 Putting it all together !!!  50 ml or 2 ounces  Sterile 2 oz. snap cap vials, 50 ml tubes or whirlpack bags  Freeze sample when testing for mastitis pathogens  Refrigerate samples when testing for SCC and milk quality  Ship overnight perferably  Mention on the label  Analyze for Milk Quality only  Analyze for Mastitis Only  Analyze for Milk Quality and Mastitis  Sampling frequency  High: 1 sample/ day for 4 days  Medium: 3 samples/ week for 2- 4 weeks  Low: 1 sample/ week for 4-8 weeks

Putting it all together ! SPC > 10,000 BTSCC > 200,000 PI 10,000 BTSCC < 200,000 Milking practices Cleaning Cooling Mastitis PI 10,000

MAC Conference May 23, 2006

MAC Conference May 23, 2006

MAC Conference May 23, 2006