Bovine Pneumonia: Individual Animal Approach Flashcards
When are cows most susceptible to bovine respiratory disease
first 6-9 months
Subjective clinical signs of BRD
Dull / depressed
BCS (is his acute or chronic)
Increased respiratory rate (tachypnoea)
Increased respiratory effort (hyperpnoea)
Ocular discharge
Nasal discharge
Mouth breathing (dyspnoea)
Coughing
Objective clinical sign of BRD
Increased temperature (pyrexia)
Harsh lung sounds / adventitious noise
Noise from URT
List some Viral BRD agents
IBR (Infectious Bovine Rhinotracheitis)
PI3 (Parainfluenza virus)
RSV (Respiratory syncytial virus)
(BVD) (Bovine Viral Diarrhoea Virus)
List some Bacterial BRD agents
Mannheimia haemolytica
Pasteurella multocida
Histophilus somni
Mycoplasma dispar
Mycoplasma bovis
List some parasitic BRD agents
Dictyocaulus viviparus
Diagnosis of BRD
Based on history, clinical signs and recorded level of morbidity
Serology of > 6 cases (paired samples 3 weeks apart)
Pathogen culture and/or identification
- Nasopharyngeal/ocular swabs
- Bronchoalveolar lavage
Postmortem examination
- +/- Virus identification
- +/- Bacteriology
- +/- Histopathology
Chronic “Cuffing” (Mycoplasmal) Pneumonia is caused by
Various (low grade) mycoplasmas
Chronic “Cuffing” (Mycoplasmal) Pneumonia has what kind of onset
Insidious
Clinical signs of mild Cuffing pneumonia
Occasional cough
Tachypnoea
Clinical signs of severe Cuffing pneumonia
Frequent cough
Tachypnoea (>60 breaths/min)
Hyperpnoea (Deeper breaths)
Decreased Exercise tolerance
Decreased Growth rate
Adventitious sounds over cranioventral lung fields
Pyrexia (<39.5°C, 103°F)
Mortality and Morbidity of Cuffing pneumonia
Morbidity up to 100%
Mortality - rare to get deaths
Prognosis of cuffing pneumonia
May resolve in mild cases without treatment
predispose to secondary bacterial infection
Mycoplasma bovis pneumonia does what to tissues
Necrotising pneumonia
Joint lesions present in ~50% of calves
Acute Enzootic (Viral) Pneumonia: Clinical Signs
Dull
Anorexic
Tachypnoeic (up to 100 breaths/min)
Hyperpnoeic
Pyrexia (39.5- 41.0°C, 103-106 °F)
Nasal discharge
Frequent coughing
Fluid sounds and crackles over cranioventral lung areas
Progressive ill thrift and weight loss
“Respiratory Cripples” – (Chronic suppurative pneumonia)
Pasteurellosis: “Transit” / “Shipping Fever” predominantly affects?
Especially a problem of weaned suckled calves
Peak incidence September-December
Most outbreaks within 4 weeks of housing (STRESS)C
Pathogens causing Paterurellosis
Mannheimia haemolytica
Pasteurella multocida
Pathogenicity of Mannheima haemolytica
Initiating agent of pneumonic pasteurellosis
Pneumonia reproduced in experimental studies
Present in nasal cavity of healthy carriers
Mixing of carriers and susceptible animals precipitates pneumonia
How to diagnose Pasteruellosis
Diagnosis by history and culture
Broncho-alveolar lavage
- Lung lesions at postmortem examination
- Tonsillar and nasal isolates
Pneumonic Pasteurellosis- Clinical Signs
Dull
Anorexic
Tachypnoeic (60-100 breaths/min)
Hyperpnoeic
Pyrexia (up to 42°C, 108°F) and nasal discharge
Adventitious lung sounds and coughing are not as marked as in enzootic pneumonia, and may be absent
Treatment for BRD
Antimicrobials
- Oxytetracycline
- Amoxycillin+/- clavulanic acid
- Tylosin
- Enrofloxacin (Baytril)
- Marbofloxacin (Marbocyl)
NSAIDS
- Flunixin, Ketoprofen, Carprofen, Meloxicam, Tolfenamic acid
Corticosteroids
Antihistamines
Fluids/Diuretics
Clenbuterol
TLC <3
Which animals to treat with antimicrobials
Obviously ‘sick’ animals, plus?…..
Threshold temperatures (39.6 °C) (Scott 1995)
Labour intensive and not widely practised
Chronic suppurative pneumonia
Inevitable end point in many cases
Reduced weight gain / fail to gain weight
Repeated bouts of ‘acute’ pneumonia
Treatment often unsuccessful: CULL
