controling subclinical ketosis to reduce curative …buiatricsforum.com/pres 2015/raboisson.pdf ·...

Controling subclinical ketosis to reduce curative antibiotic use

D. Raboisson, M. Barbier

EBF 2015 Rome

15st october 2015

Subclinicalketosisof dairycows

Placental retention ↑

Metritis ↑

Reproduction performances ↓

Clinical mastitis ↑

SCC ↑

Abomasum displacement ↑

Culling ↑Lameness ↑

Milk ↓

Clinical ketosis ↑

• SCK is expected to increase curative antibiotic use– Because SCK promotes infectious diseases that are treated among

other with antibiotics (some of them being critical)

• Control of SCK is based on– Herd and diet management prepartum and early postpartum

– Use of Kexxtone® (monensin) for cows at risk for SCK

• Objective

– To quantify the decrease in curative antibiotic use allowed by the decrease in SCK prevalence, using or not Kexxtone®

Subclinical ketosis (SCK)

Methods(step1)

1−c

T+ (Farmer

treats)

T−(Farmer

doesn’t treat)

T+ (Farmer

treats)

R−

(cows

not at

risk) T−(Farmer

doesn’t treat)

R+

(cows

at

risk)

r

1−r

p

1−q

1−p

q

HERD

K+

(cow has SCK)

K+

(cow has SCK)

K+

(cow has SCK)

K+

(cow has SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

a

b

c

d

1−d

1−b

1−a

Methods(step2)

T+ (Farmer

treats)

T−(Farmer

doesn’t treat)

T+ (Farmer

treats)

R−

(cows

not at

risk) T−(Farmer

doesn’t treat)

R+

(cows

at

risk)

r

1−r

p

1−q

q

HERD

K+

(cow has SCK)

K+

(cow has SCK)

K+

(cow has SCK)

K+

(cow has SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

a

b

c

d = basic « natural » risk of SCK

b = d * ORSCK_if_At Risk for SCK

c = d (Kexxtone® not efficacy on cows not at risk for SCK)

a = b * (1- EfficacyKexxtone)

1−p

1−c

1−d

1−b

1−a

Methods(step2)

T+ (Farmer

treats)

T−(Farmer

doesn’t treat)

T+ (Farmer

treats)

R−

(cows

not at

risk) T−(Farmer

doesn’t treat)

R+

(cows

at

risk)

r

1−r

p

1−q

q

HERD

K+

(cow has SCK)

K+

(cow has SCK)

K+

(cow has SCK)

K+

(cow has SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

a

b

c

d

Prevalence = rpa + r(1−p)b + (1−r)qc + (1−r)(1−q)dTargeting index= rp + (1-r) * (1-q)

= basic « natural » risk of SCK

b = d * ORSCK_if_At Risk for SCK

c = d (Kexxtone has no efficacy on cows not at risk for SCK)

a = b * (1- EfficacyKexxtone)

1−p

1−c

1−d

1−b

1−a

Methods(step3)

T+ (Farmer

treats)

T−(Farmer

doesn’t treat)

T+ (Farmer

treats)

R−

(cows

not at

risk) T−(Farmer

doesn’t treat)

R+

(cows

at

risk)

r

1−r

p

1−q

q

HERD

K+

(cow has SCK)

K+

(cow has SCK)

K+

(cow has SCK)

K+

(cow has SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

a

b

c

d

1−p

1−c

1−d

1−b

1−a

Methods(step3)

T+ (Farmer

treats)

T−(Farmer

doesn’t treat)

T+ (Farmer

treats)

R−

(cows

not at

risk) T−(Farmer

doesn’t treat)

R+

(cows

at

risk)

r

1−r

p

1−q

q

HERD

K+

(cow has SCK)

K+

(cow has SCK)

K+

(cow has SCK)

K+

(cow has SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

a

b

c

d

1−p

1−c

1−d

1−b

1−a

D+ (cow has disease)

D- (cow has no disease)



PDI

1-PDI

PDI * ORDI

1-(PDI*ORDI )

Methods(step3)

T+ (Farmer

treats)

T−(Farmer

doesn’t treat)

T+ (Farmer

treats)

R−

(cows

not at

risk) T−(Farmer

doesn’t treat)

R+

(cows

at

risk)

r

1−r

p

1−q

q

HERD

K+

(cow has SCK)

K+

(cow has SCK)

K+

(cow has SCK)

K+

(cow has SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

K-

(cow has no SCK)

a

b

c

d





PDI

1-PDI

PDI * ORDI

1-(PDI*ORDI )

AN

TIB

IOT

ICT

RE

AT

ME

NT

FO

RE

AC

HD

ISE

AS

E













1−p

1−c

1−d

1−b

1−a

↓↓ FOR ALL DISEASES ↓↓

• Calibration– ORDI

– PDI

– Others

Methods

Scenario 1C Scenario 2C Scenario 1A Scenario 2A

ORSCK_if_At Risk for SCK 2.13 4.5 2.13 4.5

Antibiotic Céphalosporines Pénicillines A

EfficacyKexxtone 0.66 0.66 0.66 0.66Basic « natural » risk of SCK (value of d)

0.15 0.15 0.15 0.15

% of ill cows treated withcuratif antibiotics

From 0% to 100%, depending on illness

• Exposition (cephalosporin, ORSCK_if_At Risk for SCK = 2,1)

Cephalosporin + Kextonne® Cephalosporin only

Results

0

500

1000

1500

2000

2500

3000

3500

0 0,2 0,4 0,6 0,8 1

Tota

l q

ua

nti

ty(g

)

% of cows at risk

Sans traitement (p=q=0) Ciblage parfait (p=1,q=0)

Toutes vaches traitées (p=q=1) Intermédiaire (p=0.8,q=0.2)

No Kexxtone® Kexxtone® on all cows

Perfectly targetedWell used

45

47

49

51

53

55

57

59

0 0,2 0,4 0,6 0,8

Tota

l q

ua

nti

ty(g

)

% of cows at risk





- 3,5%- 6%

- 9%

- 11%- 7%

0

500

1000

1500

2000

2500

3000

3500

0 0,2 0,4 0,6 0,8 1

Tota

l q

ua

nti

ty(g

)

% of cows at risk






Perfectly tagetedWeel used

40

45

50

55

60

65

70

75

0 0,2 0,4 0,6 0,8

Tota

l q

ua

nti

ty(g

)

% of cows at risk





- 17%

- 12%

- 7%

- 25%

- 15%

Results


Cephalosporin + Kextonne® Cephalosporin only


Decrease in exposition Decrease in SCK prevalenceCurative antibiotics only

The decrease in exposition is dramatically lower compared to the decrease in prevalenceBecause cows without SCK have a minimal level of risk of diseases and antibiotic treatments

Results






0

10

20

30

40

50

60

0,1 0,2 0,3 0,5 0,8% o

f d

ecr

ea

sein

an

tib

ioti

ce

xp

osi

tio

n

% of cows at risk

Ciblage parfait (p=1,q=0) Toutes vaches traitées (p=q=1)

Intermédiaire (p=0.8,q=0.2)

Kexxtone® on all cows

0

10

20

30

40

50

60

0,1 0,2 0,3 0,5 0,8%

of

de

cre

ase

in p

rev

ale

nce

% of cows at risk

Ciblage parfait (p=1,q=0) Toutes vaches traitées (p=q=1)

Intermédiaire (p=0.8,q=0.2)Kexxtone® on all cowsPerfectly targeted

Well used

Perfectly targeted

Well used


95 % confidence interval 95% prediction interval

Results are robust for a large population, but no prediction at the farm level

40

45

50

55

60

65

70

75

0 0,2 0,4 0,6 0,8 1

Tota

l q

ua

nti

ty (

g)

% of cows at risk



Confidence and prediction






10

30

50

70

90

110

130

0 0,2 0,4 0,6 0,8To

tal

qu

an

tity

(g)

% of cows at risk




Perfectly targetedWeel used Perfectly targeted

Weel used

• Without using Kexxtone®,

decrease of % of cows at risk

� a decrease in prevalence of SCK from 68% to 17%

� an 25 % average decrease in curative antibiotic used

• Use of Kexxtone® allows to keep the use of curative antibiotic at low levels (few SCK)

• Compared to lack of treatment, use of Kexxtone® allows a decrease up to 25% of curative antibiotics(30-35% in extreme cases) for herds / cows at risk

• No prediction at cow/herd level (variability), but results are robust for large populations

• Other situations and scenarios not shown here (sensitivity analysis)

Bring home message

Thanks to Michael MouniéElodie KhenifarClélia CahuzacElise Maigné

A preliminary work used as support of the present study has been funded by the INRA program “Sustainable Management of Animal Health” Ruminflame

The present work was funded by Elanco France.

Acknowledgement and conflict of interests

controling subclinical ketosis to reduce curative …buiatricsforum.com/pres 2015/raboisson.pdf ·...

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