The document discusses bovine respiratory disease (BRD) in veal calf production in Flanders, finding high rates of mortality and morbidity, with pneumonia being the most common cause. Multiple pathogens are involved in BRD cases, including Mycoplasma bovis, Mannheimia haemolytica, and bovine viral diarrhea virus. A strategic approach to treating BRD is recommended, focusing on quick treatment, sufficient duration of broad-spectrum antibiotics, and use of long-acting single-dose products to reduce relapse.

1. Dierengezondheidszorg Vlaanderen vzw
1
Dealing with BRD in Flemish
veal calf production
Dr. Koen De Bleecker
Dierengezondheidszorg Vlaanderen vzw

2. 2
1. Introduction
2. Situating the problem
3. Evaluating the BRD-
complex
4. Strategic approach
Content

3. 3
Veal industry

4. 4
• Small market: +/- 290.000 slaughtered calves
on 1100 herds
• 95% in Flanders
• 70% in the northern part (province of Antwerp)
• Strongly integrated (>90%)
• France (32%)> Netherlands (24%)> Belgium
(7%)
Veal calf production -Flanders

5. 5
• 14 days on arrival – from different farms
• 3 breeds: dairy calves( 60%), Belgian Blue-
calves(20%)and mixed breeds(20%)
• Individual untill 6 weeks after arrival, then
groupe housing
• Slaughtered at 8 months (250kg)
• Nutrition
‐ mainly milk powder
‐ feed rich in fiber: 50 g to 250g at 20
weeks
• Production of white veal meat → ‘controlled’
anemia
Veal calves

6. 6
• Grown within ‘VEEPEILER’
‐ Veepeiler= Monitoring program for cattle diseases
• Financed by Belgian Sanitary Fund= farmers money!!
• Main Purpose: monitoring infectious diseases in cattle: both
existing and emerging
• Means:
‐ Consultancy and advice for individual farms with specific problems:
» guidance
» extra analyses
» follow-up
‐ Shorttime projects with focus on practical and current topics:
» Veal calf BRD project
Situating the project

7. 7
 1/. Situate the problem: mortality/morbidity figures
 2/. Evaluate the BRD complex in the veal calf
industry
identify the pathogens
 evaluate immunity
 evaluate environmental factors
 3/. Strategic approach of BRD in the veal calf
industry
Veal calf BRD project: aims & goals

8. 8
• Gather figures on mortality/morbidity:
‐ 15 herds (5837 calves)
• 5 HF – herds (2743 calves)
• 5 Belgian Blue – herds (1487 calves)
• 5 mixed breed – herds (1607 calves)
‐ between oct 2007- oct 2009
1/ Situate the problem
‘‘Measurement is the first step that leads to control and eventually to
improvement. If you can’t measure something, you can’t understand it. If
you can’t understand it, you can’t control it. If you can’t control it, you can’t
improve it.’’
H. James Harrington

9. Pneumonia border line the most important cause of mortality
Peritonitis/polyserositis and acute ruminitis important
Average mortality= 5,17% (127/2458)
Dairy 4,38 %
Mixed breed 4,76 %
Belgian Blue 7,43 %
9
Global mortality

10. Global mortality
2 peaks of mortality caused by pneumonia:
week 4‐8 (acute disease) and week 17‐23 (mainly loss due to chronic pneumonia) 10

11. 1 large peritonitis peak: week 8‐11
Polyserositis/peritonitis peak immediatly after a pneumonia peak
11
Global mortality

12. Peritonitis/polyserositis in veal calves
Exsudative fibrinous peritonitis
often with pneumonia, sometimes pleuritis
Several agents have been cultured:
Pasteurella, Mannheimia, E. coli, Klebsiella,…
Etiology?
Hematogenous?
Primary source:
• lung?
• abomasum?
Catry et al., 2005 J Clin Microbiol.43(3):1480-3
12

13. • Belgian Blue (7.43%)>> crossbreeds (4.76%) > dairy breed (4.38%)
• Pneumonia of greater importance in the Belgian Blue and crossbreed
• Belgian Blue: enterotoxaemia, arthritis, necrobacillosis
• Dairy breed: omphalitis and perforating abomasal ulcers
• All breeds: polyserositis/peritonitis, acute ruminitis and diarrhea
13

14. Global morbidity
19.44% individually treated (478/2458 calves at risk)
Pneumonia most important reason for individual treatment
Diarrhea, otitis externa/media, peritonitis/polyserositis and arthritis important •14

15. Pneumonia peak: week 2‐5 (climax week 5) (age: 24‐49 days)
Diarrhea: week 1‐3
Peritonitis/polyserositis: week 7‐11
2e half: limited amount of individual treatment
15

16. Dairy 17.12 %
Mixed
breed 21.73 %
Belgian
Blue 21.62 %
• Pneumonia: more treatment in Belgian Blue
(expensive calves‐farmer influence?‐ increased susceptibility pneumonia)
• Belgian Blue: necrobacillosis, arthritis (also mixed breed)
• Otitis: dairy and mixed
• Peritonitis: dairy
16

17. Pneumonia on all farms the most important reason for treatment, but large variation
Farm related: peritonitis, otitis, arthritis, omphalitis
True differences or ‘farmers nature’?
17

18. Morbidity parameters
farm 1 HF farm 2 HF farm 7 HF
farm 3
BBxHF
farm 5
BBxHF
farm 4
BWB
farm 6
BWB average
SARGEANT
ET AL. **
Percentage individually treated 15,72 27,31 13,77 25,81 16.67 21,84 20.35 20.35
59,1
(46‐78,5)
Number of treatment days 941 238,00 222,00 115,00 70,00 394,00 334.43 334.43 ‐
Number of treatment days per
treated calf 7.23 3.35 3.64 2,40 2,80 5,71 6.12 4.46
5,6
(4,5‐10,6)
Number of treatment days per
calf 1,14 0.91 0,50 0,62 0,47 1,25 1.31 0.89
3,3
(3,1‐8,2)
* * Sargeant et al., 1994, Canadian Journal of Veterinary Research 58, 189‐195
In Belgium less individual treatments compared to Canada
Major farm differences
Number of individual treatments: high on both Belgian blues
Adequate individual therapy length, but not always on consecutive days
But substantial amount of group treatments 18

19. Group treatments
42 group treatments for 6 farms: average= 7 (4‐12)
BRD most important reason for group treatment
* Data on 6 farms (farm 4 excluded)

20. Conclusions
• Mortality and morbidity: Belgian Blue > crossbreed > dairy
• Pneumonia
– at very young age: 24-49 days (week 2-5 after arrival)
– more problems in the Belgian Blue breed
– all farms, large variation
• Peritonitis/polyserositis
– farm related
– all breeds: differences in clinical presentation between dairy
and Belgian Blue
• Acute ruminitis
– all farms, large variation between farms 20

21. Conclusions
• Breed predisposition
– Belgian Blue: arthritis, necrobacillosis, pneumonia,
enterotoxaemia
– dairy breed: peritonitis/polyserositis, perforating abomasal
ulcers
• Farm related prevalence
– peritonitis/polyserositis, otitis, arthritis, omphalitis,
pneumonia, diarrhea, acute ruminitis
• Antibiotic use
– extensive!! (group >> individual)
21

22. 22
• Multifactorial
• Complex interaction of different factors
(animal-environment-pathogens)
• Tendency to overestimate the importance of
the pathogens involved!
2/ Evaluate the BRD-complex

23. Multifactorial model
Environ-
ment
Animal
Pathogens
BRD• Breed
• FPT ( colostrum)
• Oppressed
immunity (BVDV)
• Malnutrition
• Se-status
• Vaccinations
• Stress
• Ventilation and
climate
• Population density
• Hygiëne
• Herd management
• Humidity
• Dust
• Irritating gasses
• Viruses
• Bacteria
• Parasites

24. Identify the pathogens

25. I
d
e
n
t
i
f
y
Sampling 24 BRD-
’outbreaks’(okt. 07- Jan. 09)
-1.serumsamples of 10
calves: Ab BRD-virussen
and Mycoplasma bovis
-2.deep nasopharyngeal
swabs
-3.post mortems

26. Bacteria: calf level
Mycoplasma strongly present on calf level
32.7% of the calves: mixed infections

27. • 32.9% calves seroconverted clearly for M. bovis during
BRD-outbreak (63.2% showing increasing Ab- titer)
• Presence of Mycoplasma bovis during peak of BRD-
problems on 23/24 outbreaks
• M. haemolytica en P. multocida 70.8% each of the
outbreaks
• All three major bacterial pathogens found in 59.1% of the
outbreaks
Mycoplasma bovis

28. Antibiotics resistance
A lot of antibiotics frequently used orally seem to work inadequately
against the common pathogens

29. • BVD most found in serovonversions
• Mixed viral infections are seldom (5,6%) BVD frequently
found in those mixed infections
Viruses: calf level

30. Still BVD most present, followed by parainfluenza
IBR and bRSV seems to be less important
Viruses: herd level

31. • Outburst peak around 6.5 weeks after arrival (1-12.5 weken)
• 28.5% of the lungs = typical lesions for Mycoplasma bovis
• Mycoplasma bovis isolated in 61.9% of the lungs
• 33%: A. pyogenes ( suppurating bacteria)
• Mannheimia en Pasteurella found only sporadical
• 60% of the calves: BVD virus positive
• 20% of the calves: RSV positive
Post mortem

33. 33
• What do we know so far?
‐ A lot of information!
‐ Problems that were found: frequent therapy failure!
• High presence of Mycoplasma bovis: few specific
treatments
• High presence of BVDV
• ‘Common’ BRD bacteria resistant to frequently used
antibiotics
‐ Too many different types of antibiotics on herd and on calf level!
‐ Insufficient in duration
‐ Insufficient in indication
3/ Strategic approach of BRD

34. 34
• What is failure of therapy?
‐ Not working of a treatment = relapsing calves
• Evaluation of one of the outburst:
3/ Strategic approach of BRD
40/182 (22%) calves were individual
treated
72,2% single treatment (11% long
shot)
27,8% two or three days treatment
same antibiotic: 20%
different antibiotics: 80%
1e treatment Amount of calves
(% of treated
animals)
Lincospectin +
Neopen
57.6%
Danofloxacine 15.3%
Cefquinome 7.7%
Tulathromycine 7.7%
Florfenicol +
marbofloxine
3.8%
Marbofloxacine 3.8%
Tilmicosine 3.8%

35. 35
• In conclusion of this outburst
3/ Strategic approach of BRD
Product Amount of days
Amoxycillin +
Colistin
6
Doxycyclin 5
Oxytetracyclin 10
Oxytetracyclin +
Tylosin
10
• 24% of the doses go to calves that
finally die!!!
• 29% of the doses given to 3 calves !!!(1
BVD positive, died)
• Group treatments
Amount of treatmentdays /treated calf:
5 days (individual) + 31 days= 36 days
Product Nb of given doses
Lincospectin 41
Neopen 43
Gentaject 1
Advocin 27
Nuflor 14
Cobactan 9
Vetalgin 3
Vetodexin 28
Meflosyl 9
Micotil 10
Metacam 3
Floxadyl 3
Emdofluxim 6
Draxxin 6
Marbocyl 5
Dicural 1
Multivit. 1
Potencil 2
212

36. 36
• What can we change in treatments?
‐ Treat quickly
‐ Treat long enough
‐ Treat with broad-spectrum
• Won’t this increase labour for the farmer?
‐ NO:
• Less relapsing calves, less treatments
• Use longacting one-shot products!
3/ Strategic approach of BRD

37. SCORE 0 1 2 3
Rectal t°C
(°C)
< 38.5 38.5-39.0 39.0-39.5 > 39.5
Cough None Induced single cough Induced repeated cough
or occasional
spontaneous cough
Repeated
spontaneous cough
Nasal
discharge
Normal, serous Limited quantities of
unilateral ‘cloud’
colored discharge
Bilateral ‘cloud’ of
excessive muceus
discharge
Abundant bilateral
and purulent
Awareness Normal Slower, but responding
to stimulus
Isolated,responding
slowly to stimulus, lying
down a lot
Strongly reduced,
few responding to
stimulus
37
Decision making on treating or not:
Score chart (McGuirk)

38. 38
• When do we treat an animal?
‐ Temp: 40°C → 3
‐ Spontaneous cough → 2
‐ Nasal discharge ‘cloud’ → 1
‐ Eyes → 0
‐ Moderate drooping ears → 1
‐ Total = 7
3/ Strategic approach of BRD
When score> 5 = treatment

39. With the thermometer in hand…
39
S h f t l

40. 40
3/ Strategic approach of BRD
Decision of first treatment:
Score chart
Long shot or 7 days
Therapy succes
Failure of therapy:
daily antibiotics
for 1 week
Therapy failure:
Moving to sick-
bay
Euthanasia?
BVD‐antigen test?
3e treatment round?
*B. Pardon
Fac. Vet.Med.
Ghent University

41. 41
• Why moving to a sick-bay?
‐ Chronically ill or relapsing calves: big shedders of
infection!
• BVD carrier
• chronically Mycoplasma infected
‐ ‘Sick-bay’: as far as possible from healthy calves
3/ Strategical approach of BRD

42. 42
• Last but not least
‐ we know that:
• calves arriving from different herds : a lot of different
pathogens!
• some pathogens (Mycoplasma!) survive in wet and
chilly stable conditions
‐ key words between 2 rounds of calves:
• 1/ cleaning
• 2/ desinfecting
• 3/ sanitary void and drying!
3/ Strategical approach of BRD

43. 43
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Thank you for your attention!
Any questions?