Challenges and consequences of restricted antibiotic use in dairy cattle in the Netherlands

Theo Lam

antibiotic usage in animals

• (Over)use of antibiotics in veterinary medicine

• Humans exposed to antimicrobial-resistant pathogens

• Some incidents… MRSA

ESBL

Political pressure……….

Decrease veterinary antibiotic use to the level of 1999

As compared to 2009:

• 20% decrease in 2011

• 50% decrease in 2013

• 70% decrease in 2015

Political pressure?

Low antibiotic usage……

MARAN annual report, 2013chickens

dairy cowsveal calves

pigsEscherichia coli

Low antibiotic resistance……

Evolution of the dairy cow

Improving antibiotic use in dairy…….

• Making antibiotic use transparent

(annual ADDD per herd)

• Very limited use of critically

important antibiotics

• No more preventive use of

antibiotics (dry cow therapy)

Making antibiotic use transparent

Making antibiotic use transparent

Animal Defined Daily Dose• The average number of days an animal is treated

Veterinary Drug Authority • Independent• Monitors and judges national trends• Sets benchmarks, identifies ‘problem herds’

Critically important antibiotics

Critically important antibiotics

3rd/4th generation cephalosporinsceftiofur, cefquinome, cefoperazone

Fluoroquinolonesenrofloxacin, danofloxacin, marbofloxacin

Long-acting macrolidstulathromycin

Polymyxin B, E

Critically important antibiotics

Only when there is no other choice, based on sensitivity…

Sales 3rd/4th gen.

cephalosporins

dairy herds

0

0,2

0,4

0,6

0,8

1

1,2

2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

1.2

1.0

0.8

0.6

0.4

0.2

0

ADDD

Blanket dry cow therapy

Blanket dry cow therapy

Prevalence study 2008:

- 87% herds blanket DCT- 11% selective- 2% no antibiotics

Sampimon et al., 2008

Selective dry cow therapy

leads to:

• an increase in (sub)clinical mastitis• limited effects at herd level• significant reduction in AB use

NB In low BMSCC herdsblanket DCT is not theeconomic optimumDC

Scherpenzeel et al., 2014, 2016, 2016

Introduction of selective DCT

• SDCT became obligatory in 2013

• Guideline SDCT launched in 2014

• What happened in real life?

What happened in real life?

• SDCT was implemented quickly (75% in 2013)

• ADDDdry cow decreased with 28%

• On a national level (sub)clinical mastitis and BMSCC did not differ from earlier years

• Management did influence the effect of SDCT: cleaning floors, PMTD, treatment of cases……

Scherpenzeel et al., 2016Santman-Berends et al., 2016

What did farmers think of it?

• >80% of farmers thought reduction of AB use important

• >75% of farmers thought SDCT was the right approach

Scherpenzeel et al., 2016

Antibiotic usage in the Netherlands

600

500

400

300

200

100

0’99 ’00 ’01 ’02 ’03 ’04 ’05 ’06 ’07 ’08 ’09 ’10 ’11 ’12 ’13 ’14

Kilograms

active

ingredients

( x 1000)

Antibiotic usage in the Netherlands

Conclusions

• Since 2009 antibiotic usage in dairy cows in the Netherlands decreased significantly

• So far without dramatic changes in dairy health

• Cooperation of different stakeholders led to a fundamental change in knowledge, attitude and behaviour

Thank you

for your attention!

If you have further

questions, meet us

at booth number 3