Early detection of bovine respiratory disease (BRD) · PDF fileEarly detection of bovine...

Early detection of

bovine respiratory disease (BRD)

in feedlot cattle: why and how?

Dr. E. Timsit DVM, PhD, Dip. ECBHM

Dr. S. Assié, DVM, PhD, Dip. ECBHM

Introduction

• Heifer, 28 days after arrival (i.e. days on feed)

• Found dead in pen, treated once the day before

• Fatal fibrinous pneumonia (M. haemolytica)

Detected and treated too late!

Introduction

1. Why is an early detection of BRD crucial?

2. How to early detect BRD?

Outline

Early BRD detection

• Maximize antibiotic action

• Avoid irreversible pulmonary lesions

• Prevent emergence of antibiotic resistances

Early antibiotic treatment in the

disease process

- Maximize clinical and bacterial cure

- Limit BRD impact on performances

Why early detect BRD?

Mannheimia haemolytica

Pasteurella multocida

Mycoplasma Bovis

Histophilus somni

Commensal organisms

M. haemolytica

(Griffin et al.,2010)


Viral infection, stress

and/or suboptimal

environment

Proliferation of bacteria in the

nasopharynx

Bacteria gain access to the

lung via aerosolized droplets

Adherence, colonization and

replication in the lung

Bacterial pleuro/broncho-pneumonia

Tissue destruction and inflammation


1) Secretion of enzymes and

toxins Lipopolysaccharide (LPS),

Leukotoxins (LKT),

Lipoolysaccharide (LOS), etc.

Lung damage Inflammation

When bacteria colonize and replicate:

Evolution of the disease process

Inflammation can lead to

tissue damage

(Panciera et al., 2010)


When bacteria replicate:

2) Emergence of bacterial resistances

Antibiotic-sensitive bacteria

Time-lag before treatment

Antibiotic-resistant bacteria

(Lipsitch & Levin, 1997; Ferran et al., 2011)

Total bacterial population > mutational frequency to resistance (10-6 to 10-8)

=> Presence of resistant population very likely (before any treatment)


When bacteria replicate:

2) Larger bacterial inoculum

Time-lag before treatment (Ferran et al., 2011)

Higher dose of antibiotic required to eradicate the bacterial inoculum

Early treatment = lower dose of antibiotic needed


Obstruction

alveolar hypoxia

Hypoxic pulmonary vasoconstriction

reduced blood flow

Normal blood flow

Normal blood flow

When pulmonary lesions and atelectasia => reduced antibiotic distribution

Reduced antibiotic distribution

Early treatment = few (or no) obstructions Increased antibiotic action


Study of Ferran et al. (2011)

Experimental lung

infection (P. multocida)

Control group

Early treatment

group

Late treatment

group

Antibiotic treatment

10 h post-infection

Antibiotic treatment

32 h post-infection

Euthanasia (48 h)

Euthanasia (48 h)

Euthanasia (70 h)


Control group Early treatment

group

Late treatment

group

% of mice with P. multocida 93% (26/28) 36% (5/14) 0% (0/14)

% of surviving mice 64% (18/28) 71% (10/14) 100% (14/14)

% of lungs with resistant bacteria 33% (6/18) 10% (1/10) 0% (0/13)

Better bacterial and clinical outcomes

Less frequent selection of resistant bacteria

Early antibiotic treatment:

Study of Ferran et al. (2011)


“Early” BRD treatment “Late” BRD treatment

Use of rumen

temperature boluses Distant examination

if BRD signs: rectal temperature

Preliminary results (30 YB in each group)

Study design

Cefquinom 2.5 mg/kg once Cefquinom 2.5 mg/kg twice

Treated animals: 22

Relapse: 6 (27%)

Global antibiotic consumption:

22*2.5 mg/Kg = 55 mg/Kg

Treated animals: 13

Relapse: 4 (30%)

Global antibiotic consumption:

26*2.5 mg/Kg = 65 mg/Kg

Study of Assié et al. (unpublished data)

BRD detection: BRD detection:


30 young bulls 30 young bulls

• To maximize antibiotic action

• To avoid irreversible pulmonary lesions

• To prevent emergence of antibiotic resistances

- Maximize clinical and bacterial cure

- Limit BRD impact on performances

In summary:


1. Why is an early detection of BRD crucial?

2. How to early detect BRD?

Outline

– Distant examination

• Owner and/or staff

• Once or twice daily

– Detection of clinical signs

• Depression

• Anorexia/dysorexia

• Increased respiratory rate

• Lacrimal and nasal

discharges, cough, etc.

• How are cattle with BRD detected?

(Duff & Gaylean, 2006)

How to early detect BRD?

• Does distant examination enable an early BRD

detection? Study of Timsit et al. (2011a) Answer: No

Rumen temperature bolus


Solution: By using automatic health-monitoring systems

B) Changes in feeding behavior => Growsafe system, ENGS system

A) Changes in body temperature rumen T°C boluses, IRT, ear mounted

thermometers

Schaefer®

Growsafe®

C) Changes in physical activity => pedometers, accelerometers


A) Monitoring body temperature to early detect BRD

Fever occurs very early in the disease process (within hours)

Experimental infection of 3 heifers (181±19 kg) with M. haemolytica (-21 h)

BRD Treatment (0 h)

(Fajt et al., 2004)



Study of Timsit et al. (2011b)

Treatment

Drinking

Fever episode

Rumen temperature of a feeder bull

BRD affected animals detected 12 to 177 h (mean = 51h)

prior to BRD treatment



Study of Schafer et al. (2007 & 2012)

BRD affected animals detected 4 to 6 days prior

to the onset of clinical symptoms of BRD



Fever Tags® (old version)

Promising tools Cheap <15€

But low sensitivity (21/46 = 46%)

• Inadequate probe

placement

• Probe displacement

• High threshold for activation New version with adjustable probe size and activation threshold

Study of McCorkell et al., accepted

“Fever Alert” distributed by Merck Animal Health (France)

need to be evaluated





thermometers

Schaefer®

Growsafe®

Yes


B) Monitoring feeding behavior

Study of Sowell et al. (1999)

Diseased feedlot cattle spent on average 30% less time at the feed

bunk than healthy cattle (46 min/day versus 60 min/day)

Growsafe®

(Sowell et al., 1998)


B) Monitoring feeding behavior

Study of Quimby et al. (2001)

Growsafe®

Decreased frequency and duration of feed bunk visit

Detected as sick by the Cusum test

Diseased cattle detected on average 4.1 days earlier than pen checker





thermometers

Schaefer®

Growsafe®

C) Changes in physical activity => pedometers, accelerometers Yes

Yes


C) Monitoring physical activity

Study of Hanzlicek et al. (2010)

Experimental infection of 14 steers

(199 kg) with M. haemolytica

M. Haemolytica infection


C) Monitoring physical activity

Study of White et al. (2012)

Experimental infection of 20 Holstein

calves (5-9 week old) with M. bovis

<10% consolidated

lung tissue

>10% consolidated

lung tissue

M. bovis infection





thermometers

Schaefer®

Growsafe®

C) Changes in physical activity => pedometers, accelerometers Yes

Yes

Yes


• Why are health-monitoring systems not currently

used in feedlots?

1st explanation = costs $$$

• Rumen temperature bolus = $35-100

• Infrared camera = $7000

• Growsafe system = $25 per head

2nd explanation = low specificity!

• Numerous “false-positive” detection

Costs are decreasing rapidly!


• Lack of specificity of fever and abnormal feeding behavior:

Up to 75% of the fever episode detected by rumen T°C bolus lasted less

than 47 hours without any treatment => viral infection only? Successful immune response? Hyperthermia?

Vaccination?

1) Study of Timsit et al. (2011b)

2) Study of Wolfger et al. (2012)

Pulling cattle only based on abnormal feeding behavior during the first

weeks on feed could lead to pull as much as 90% of the healthy animals => Adaptation to the bunk?

How can the specificity of fever and anorexia/dysorexia be improved?


• How to improve specificity of fever?

– by taking into consideration the duration of fever

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0 to 24 h 24 to 48 h >48h

No BRD signsBRD signs and treatment

n=45 n=29 n=21

75% of fever episodes lasting longer

than 48 hrs led to clinical BRD

(Timsit and Assié, personal communication)

48 hrs was also proposed by

Radostits et al., 2010

Recommendations: treat cattle with fever

48 hrs after onset (if no other signs)


• How to improve specificity of fever and abnormal

feeding behavior?

– by combining this parameters (i.e. series testing)

+

Pull and treat only cattle having concomitantly fever and

anorexia/dysorexia


• To describe the changes in body temperature,

feeding behavior and physical activity associated

with BRD

Objective

• 560 steers studied during first 50 DOF

• Simultaneous monitoring of body temperature,

feeding behavior and physical activity

Materials and methods

On-going study (Timsit and Booker)


On-going study (Timsit and Booker)

Preliminary data (n = 12 sick animals)

• Fever (n =12): onset = 2 to 9 d before detection/treatment; med = 4 d

• Anorexia/dysorexia (n = 9): onset = 0 to 3 d after fever; med = 2 d

• Decreased activity (n =8): onset = 0 to 3 d after fever; med = 2 d

Steer n°9569 Steer n°9569

Treatment

Treatment


• Early BRD detection i) limits impact of BRD on

performance, ii) maximizes clinical and bacterial

cure and iii) reduces emergence of bacterial

resistances

• Distant examination alone cannot enable an

early BRD detection

• Health monitoring systems can enable an early

BRD detection but further research is needed

and is performed already!

Take home message

Thank you very much for your attention!

Source: Dr. Eugene Janzen

• Duff G et al.. 2007. Board-invited review: recent advances in management of highly stressed, newly received feedlot cattle. J Anim Sci. 85:823-40.

• Fajt V et al. 2004. Effect of danofloxacin and tilmicosin on body temperatures of beef calves with pneumonia experimentally induced by inoculation with Mannheimia haemolytica. Am J Vet Res. 65:610-615.

• Ferran A et al. 2011. Impact of early versus later fluoroquinolone treatment on the clinical: microbiological and resistance outcomes in a mouse-lung model of Pasteurella multocida infection. Vet Microbiol. 148: 292-297.

• Griffin D et al. 2010. Bacterial pathogens of the bovine respiratory disease complex. Vet Clin North Am Food Anim Pract. 26:381-394.

• Hanzlicek G et al. 2010. Serial evaluation of physiologic, pathological, and behavioral changes related to disease progression of experimentally induced Mannheimia haemolytica pneumonia in postweaned calves. Am J Vet Res. 71: 359-369.

• Lipsitch M et al. 1997. The population dynamics of antimicrobial chemotherapy. Antimicrob Agents Chemother. 41:363-73.

• McCorkell et al. 2014. Limited efficacy of Fever Tag® temperature sensing ear tags in calves with naturally occurring Bovine Respiratory Disease or induced Bovine Viral Diarrhea Virus infection. Can Vet J. Accepted.

• Panciera RJ et al. 2010. Pathogenesis and pathology of bovine pneumonia. Vet Clin North Am Food Anim Pract. 26:191-214.

• Quimby W et al. 2001. Application of feeding behaviour to predict morbidity of newly received calves in a commercial feedlot. Can J Anim Sci. 81: 315-320.

• Schaefer A et al. 2012. The non-invasive and automated detection of bovine respiratory disease onset in receiver calves using infrared thermography. Res Vet Sci. 93: 928-935.

• Schaefer A et al. 2007. The use of infrared thermography as an early indicator of bovine respiratory disease complex in calves. Res Vet Sci. 83: 376-384.

• Sowell BF et al. 1999. Feeding and watering behavior of healthy and morbid steers in a commercial feedlot. J Anim Sci. 77:1105-1112.

• Timsit E at al. 2011a: Early detection of bovine respiratory disease in young bulls using reticulo-rumen temperature boluses. Vet J. 190: 136-142.

• Timsit E at al. 2011b: Fever episodes without visually apparent clinical signs in newly-received beef bulls at fattening operation: occurrence, duration and impact on performance J Anim Sci. 89: 4272-4280.

• White BJ et al. 2012. Clinical, behavioral, and pulmonary changes in calves following inoculation with Mycoplasma bovis. Am J Vet Res. 73:490-497.

• Wolfger B et al. 2012. Pattern recognition of feeding and drinking behaviour as a tool in early identification of diseased feedlot animals. 13th ISVEE. Maastricht. Netherland.

Literature cited

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