Current Status and Future Challenges in Mastitis

Research

Henk Hogeveen

Joe Hogan

This mastitis forum

Eric Hillerton Henk Hogeveen Herman Barkema Joe Hogan Karin Persson Waller Satu Pyorala Steve Oliver Theo Lam Ynte Schukken

Topics

Current status• Pathogens• Diagnosis• Immunology• Therapy• Environment• Milking equipment• Management

• Socio-economic Wrapping up

Etiological agents• Countries, regions, farms

• Stage of lactation

• Seasons

• Evolve

Pathogens

Staphylococci Staph aureus

• strain diversity

• related genotypes within herd

Pathogens

Photo: SVA, Uppsala

• CNS - increasing interest in many countries• Multiple species and strains

• Dfferential diagnostics

Pathogens

Streptococci• Strep agalactiae

• still concern in some countries

• genotypes between human and bovine isolates

Pathogens

Photo: SVA, Uppsala

• Strep dysgalactiae • (environmental/contagious)

• fresh heifers

Pathogens

• Strep uberis• housed and pastured systems

• strain differences

Pathogens

Coliforms • severity = host response

• genetically heterogenous group• mild to severe

• acute to chronic

PathogensPhoto: SVA, Uppsala

Pathogenesis• bacteria and host

Epidemiology & Ecology• genotype and environment

Emergence of ”new and old” pathogens

Future challenges - Pathogens

Topics

Current status

• Pathogens

• Diagnosis• Immunology

• Therapy

• Environment

• Milking equipment

• Management

• Socio-economic Wrapping up

Bacteriological culture

Somatic cell counts

Soluble indicators of inflammation

Diagnostics

Sample collection

Sample handling

Laboratory techniques

Interpretation

Standardization

Precision on antibiotic selection

Low specificity = false-positives

On Farm Diagnostics

Detection of genes

ID organism

Identify virulence factors

Clonal variance

PCR

Simple low-cost

Rapid on farm

RT Interpretation - Implementation

Future Challenges – Diagnostics

Topics

Current status

• Pathogens

• Diagnosis

• Immunology• Therapy

• Environment

• Milking equipment

• Management

• Socio-economic Wrapping up

Host Defense

• SOL

• Breed

• Genotype

• Age

• Milk yield

• Nutrition

• Existing infection

Host defense

Teat Canal Phagocytic Cells Soluble factors

Innate Immunity

Macrophages/monocytes Lymphocytes Antibodies

Acquired Immunity

Cytokines• Recruit

• Class switch

• Activate

• Up regulate/down regulate

Bridge Between

Whole cell bacterins Subunit vaccines Adjuvants Route

Vaccination

Vaccine Virulence factors Genotyping Environmental factors

Future Challenges – Host Defense

Topics

Current status• Pathogens• Diagnosis• Immunology• Therapy• Environment• Milking equipment• Management

• Socio-economic Wrapping up

Eliminate IMI Prudent use of antimicrobials Welfare of animal

Therapy

28

Treatment should be targeted towards the causing pathogen

OIE World Organisation for Animal HealthTerrestrial Animal Health Code

GUIDELINES FOR THE RESPONSIBLE ANDPRUDENT USE OF ANTIMICROBIAL AGENTSIN VETERINARY MEDICINE

Broad-spectrum antibiotics

Prudent? Efficacious?

29

The longer, the better? Efficacy of longer treatment is available in:

• Staphylococcus aureus

• Streptococcus uberis

30

Duration of Treatment

What is long? Very few comparative trials > 5 days may seldom be economical

Duration of Treatment

Pharmacokinetics

Route and duration

Antimicrobial resistance

Economical benefits

Alternatives to antibiotics

32

Future challenges - treatment

Topics

Current status• Pathogens• Diagnosis• Immunology• Therapy• Environment• Milking equipment• Management

• Socio-economic Wrapping up

Biological

Physical

Chemical

Environment

Fecal contamination

Moisture

Organic matter

Reduce Exposure to Pathogens

Exposure = Density

Confinement Pasture

Exposure vs Susceptibility

Future Challenges – Environment

$ $$$$$ Waste/Recycle Ecology/Image Welfare

Topics

Current status• Pathogens• Diagnosis• Immunology• Therapy• Environment

• Milking equipment• Management

• Socio-economic Wrapping up

Acts as a vector to transfer pathogens

Damages the first line of udder defence• Teat

• Canal

Role of machine milking in udder health

Cyclic and irregular vacuum fluctuations

Claw volume increased to 116 ml -9%

Small milk tube bore increased to 11 mm -16%

Add smt air bleeds (0.57 mm) -18%

Long pulse tube restrictor (3 mm) -19%

Change to alternate pulsation -20%

COMBINED EFFECT -84%

Key changes in machine milking affecting cyclic fluctuations

Knowledge on irregular vacuum fluctuations

Blocked air bleeds Low reserve Excessive losses Ineffective regulator Liner slip Cluster attachment Cluster removal

ALL AFFECT VACUUM STABILITY AND BACTERIAL TRANSFER

Milk flow

Milk flow

Bad

Good

0

20

40

60

80

0 1 2 3 4 5

Liner age

% q

ua

rte

rs

-10

0

10

20

30

40

50

60

70

0 1 2 3 4 5

Liner age

% t

eats

wit

h c

olo

ur

resp

on

se

Completeness of milking

Effect on teat color

Liner surface 0 milkings 4000 milkings

Effect of liner age

h

2 min 5 min0 min

0 min 5 min2 min

Teat condition and overmilking

Heifers Cows

Flow rate (ml/min) 200 400 200 400

Machine-on time (min) 5.5 5.0 7.9 7.4

Yield (kg) 21.1 21.2 31.5 31.6

Teat score 1.3 1.0 1.7 1.1

New infections, % cows 16 15 15 15From MD Rasmussen

Effect of ACR setting

Peri-harvest diagnosis

Precision dairy farming Milk harvesting technology

• Parlor performance

• In-line/on-line detection of udder inflammation

• Other diseases

5 robots: 2 prep, 2 attach, 1 post-spray

http://www.youtube.com/watch?v=--e_AOeOC4s

In-line/on-line diagnostics

Small amount of milk is immediately diverted into diagnostic device:• Milk meters: milk weight, conductivity, temperature.

• Diagnostic systems:

• Light scattering (fat, protein, lactose, SCC)

• Bio-sensors (LDH, progesteron, BHBA

• Electronic tongue

• Thermal camera

• Light diffusion (color)

• Capilary activity (CMT-like, SCC)

• ……

Future challenges – machine milking

Target• Swift and complete removal of milk

• Remain the integrity of milk and health of teat Integrate sensors

• Without disrupting milking process

• Properly evaluated functioning (also economic)

• Associated “new” management Further automation Managing the teat canal

• Teat closure

Topics

Current status• Pathogens• Diagnosis• Immunology• Therapy• Environment• Milking equipment

• Management• Socio-economic

Wrapping up

• Dry cow antibiotics

• Post milking teat disinfection

• Milking and milking machine

• Clinical mastitis cases

• Chronically infected cows

Basis for numerous on farm udder health programs

Have shown to be effective

The 5-point plan on contagious mastitis

6,9

5,4

2,5

1,6

0

0,9

1,5 1,4

0,9

1,21,2 1,21,4

1,7

1,1

6,2 6,1

3,4

3,7

1,8

0

1

2

3

4

5

6

7

8

1973 1975 1980 1985 2003

Years

Pre

vale

nc

e (

%)

Streptococcus agalactiae

Streptococcus dysgalactiae

Streptococcus uberis

Staphylococcus aureus

Sampimon et al., 2009

0

1

2

3

4

5

6

7

8

1973 1975 1980 1985 2003

Streptococcus agalactiae

Streptococcus dysgalactiae

Streptococcus uberis

Staphylococcus aureus

Dutch prevalence studies

establishment of goals for udder health

maintenance of clean, comfortable environment proper milking procedures proper maintenance and use of milking equipment good record keeping appropriate management of clinical mastitis during

lactation effective dry cow management maintenance of biosecurity for contagious pathogens and

culling of chronically infected cows regular monitoring of udder health status periodic review of mastitis control program

The 10 point plan

Koegebonden

Omgeving

SAG SAU SDY ECOSUB

STC

Koegebonden

Omgeving

Koegebonden

Omgeving

SAG SAU SDY ECOSUB

STC

Contagious mastitis

Environmental mastitis

Infectious pressure

Zadoks, 2002

0%

10%

20%

30%

40%

50%

60%

70%

0 2 4 6 8 10 12 14 16 18

% nieuwe attenties

% s

core

3 e

n 4

uier

% s

core

3 a

nd

4

% s

core

3 a

nd

4

% new infectionsBMSCC

Hygiene and udder health

Schreiner and Ruegg, 2003

Prevent other contact with the milking machine

More than taking measures

Evaluation• Udder health

• BMSCC

• Incidence rate clinical mastitis

• Cows with high SCC

• …..

• Intermediate factors

• Udder hygiene

• Teat condition

• ….

• Tools are available

Teat scoring strategy

-Straightforward management:

replace after 2500 milkings

- What are farmers doing?

Remember the liners …

0

10

20

30

40

50

3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19Frequency liner replacement

Olde Riekerink and Sampimon, 2008

05

10

15

20

Aa

nta

l bed

rijv

en

0 2500 5000 10000Tepelvoeringen worden vervangen na melkingen

Num

ber

of h

erds

70%

Milkings before replacement

Future challenges – Management

(Further) develop management measures and tools• Applicable for a variety of modern dairy

farmers

• Straightforward

• Use of technology (precision dairy farming)

Estimate effect of management measures (“clinical trials”)• Give advisor arguments to “sell” improved

management

Topics

Current status• Pathogens• Diagnosis• Immunology• Therapy• Environment• Milking equipment• Management

• Socio-economics Wrapping up

Literature (€)1€ = 1.27$US

Bar2008

Halasa2009

Hagnestam-Nielsen2009

Huijps2008

Level Cow Cow Cow-year Cow

Milk production losses - 11 78 36

Labour - 11 - 4

Treatment - 14 - 15

Culling - 46 - 22

Death - 0 - 0

Veterinarian - 2 - 1

Milk quality - 0 - 0

Materials - 0 - 0

Diagnostics - 0 - 0

Total 61 84 97 78

Mastitis costs money

Estimations: $US 77 – 123 /cow/year Variation between farms:

• The Netherlands: $US 99 -195

• US: $US 45 – 620

Farmers attitude:• Know mastitis = $$$$

• Underestimate the costs

Specific studies on treatmentspecifically subclinical mastitis

Streptococci: € 12/treatment (Swinkels et al., 2005a)

• Partial budget model R = 0.21 Staphylococci: - € 21/treatment (Swinkels et al., 2005b)

• Partial budget model R = 0.32 Streptococci: - € 11/treatment (Steeneveld et al., 2007)

• Stochastic model Gram positive: € 2,601/100 cows

(Van den Borne et al., 2010)

• Stochastic dynamic model

Additional expenditures

Reduced losses Net benefit

Milk cows with clinical mastitis last 37 16 -21

Milk cows with subclinical mastitis last 104 20 -84

Use of separate cloths during udder preparation 26 9 -17

Wash dirty udders during udder preparation 3 9 6

Prestripping 34 9 -25

Use of milkers’ gloves during milking 1 9 8

Post milking teat disinfection 31 31 -0

Back-flushing clusters after milking a cow with clinical mastitis 1 11 10

Back-flushing clusters after milking a cow with subclinical mastitis 123 15 -108

Replace teat cup liners in time 13 11 -2

Use of a treatment protocol 7 15 8

Application of blanket dry cow therapy 9 36 27

Keep cows standing after milking 2 12 10

Feed additional dry cow minerals 13 13 0

Prevent overcrowding 23 13 -10

Clean boxes 54 15 -39

Clean yards 51 8 -43

Optimize feed ration 24 13 -11

Money is not the only motivator

Theory of planned behaviour…..and there are lots of other frameworks

There is an intention-behaviour discrepancy among farmers

Future challenges – socio economics

Cost calculations at chain level• More than accumulation of individual farms

• What are economic consequences of a loss of image

Cost-effectiveness of management• Lack of clinical trials

• Effect of measure depends on assumptions (dynamics)

More insight in motivating farmers• Bringing the message

• Money

• Other factors

Topics

Current status• Pathogens• Diagnosis• Immunology• Therapy• Environment• Milking equipment• Management

• Socio-economics Wrapping up

Reality in developed countries

The ‘consumer’ demand:

• A safe healthy product

• Healthy happy cows

• Environmental friendly

Government (politicians) demands:

• No risk for humans Human medicine demands:

• Decrease of antibiotics and hormones in cattle• Deal with (potential) zoonotic diseases

Business behavior results in an increase in herd size

Consequences

Consumers “in the barn” Restrictive use of antibiotics and

hormones Change in definition of “Quality” More organic farms Control of zoonotic disease requires Changed farming systems

So …

Mastitis was and remains:• A production (economic) disease

• A welfare burden

Mastitis is becoming:• An image issue

• A sustainability issue• (less mastitis -> less culling -> less youngstock

raising -> less greenhouse gas emissions etc.

Of increased importance

Finally

We’ve come from far, we’ve done a lot There are many challenges ahead of us

We acknowledge the Dutch dairy industry for initiating this mastitis forum