Calf Problems: Pneumonia Flashcards
- Interacting risk factors resulting in BRD.
- Average delay to time of first calving in cattle that have suffered BRD.
- % reduction in milk yield in cattle that have been affected by BRD.
- Stress risk factors.
Immunity of calves.
Pathogens able to take advantage of conditions. - 2wks.
- > 2%.
Why does Enzootic pneumonia occur in calves?
- Calf lungs relatively inefficient due to position.
- Problems esp. w/ R apical and cardiac lobes.
- Build up of fluid and debris.
- Cattle lung small for size of animal.
Risk factors of Enzootic pneumonia.
Calf source.
Colostrum.
Housing.
Temperature.
Damp/humidity/ventilation/dust.
Nutrition/water.
Fear/anxiety.
Castration/dehorning.
Management.
Pathogens of Enzootic pneumonia.
Para-influenza 3.
Bovine Respiratory Syncytial Virus (BRSV).
Bovine Herpes Virus 1 (BHV-1/IBR).
BVD/MD Virus.
Coronavirus.
Mycoplasma spp. (bovis and dispar).
Histophilus somni.
Mannheimia haemolytica.
Pasteurella multocida.
- Via what receptor does PI3 act?
- Vaccines available.
- Neuraminidase receptor to penetrate the mucociliary layer.
- Live and intranasal vaccines.
- Is infection w/ BRSV mild, moderate or severe?
- Vaccines available.
- Often severe w/ major involvement in calf enzootic pneumonia.
- live and inactivated.
Intranasal vaccine combined w/ PI3.
- What conditions are needed for production of initial lesions by mycoplasma spp?
- Subspp. of mycoplasma affecting cattle?
- Stress conditions.
- M. bovis and M. dispar.
- Which bacterial spp. are by far the commonest to be isolated from enzootic pneumonia?
- In which part of the respiratory tract are these spp. often found?
- Effect of these spp. on lungs.
- What cells does M. haemolytica affect?
- Mannheimia haemolytica and Pasteurella multocida.
- URT - esp. nasopharyngeal area.
- Permanent damage - consolidation.
- Ruminant-specific phagocytes (potent leukotoxin).
- What diseases is P. multocida involved in?
- What diseases is P. haemolytica involved in?
- P. haemolytica biotypes.
- bovine pneumonia, haemorrhagic septicaemia, atrophic rhinitis (pigs), dog and cat bites.
- Shipping fever in cattle.
- A = arabinose (Mannheimia haemolytica).
T = trehalose (Bibersteinia trehalosi).
- When is the peak incidence of enzootic pneumonia in the UK?
- Clinical signs range.
- Respiratory rate w/ disease?
- HR w/ disease?
- What may cause droopy ears and slight head tilt?
- Late November to xmas and late winter to spring (block calving, winter housing).
- Varying from clear ocular discharge to “full blown” bronchopneumonia. Fever a key sign. Anorexia variable. Coughing. Issue often ventral on auscultation. Nasal discharge clear then purulent. Typical posture of acute cause: depressed, dull, ears down, elbows abducted, may have neck extended.
- 60-70breaths/min.
- > 120/min.
- Middle ear disease - mycoplasma otitis.
Differentials of enzootic pneumonia.
Calves suddenly brought inside:
- need to rule out Dictyocaulus viviparus.
Or White Muscle Disease.
- Vitamin E deficiency.
- Usually on turn out.
- Can get respiratory involvement.
- V weak.
- Often frothy and bloody nasal discharge.
Or Calf Diphtheria.
Or Salmonellosis.
Or Inhalation or Aspiration pneumonia:
- obvious problem w/ single calf.
- careless stockman/drenching.
- sudden onset, very dull, anorexic, pyrexia, pain.
- if extensive, get necrotising pneumonia and death.
- if less severe, need prompt ABX Tx to save.
Or congenital cardiac defect (VSD common, loud systolic murmur).
Or D+ w/ subsequent acidosis (trying to blow off CO2).
Neonatal Respiratory Distress Syndrome:
- uncommon, single calf, often premature.
- type II pneumocytes not producing surfactant (lungs do not inflate properly).
- severe dyspnoea soon after birth.
- harsh adventitious sounds.
- no heart murmur but tachycardia.
Acute pneumonia.
Histophilus somni:
- large dairy herds.
- need risk factors (stress).
- often young animals.
- fever, anorexic, severe pneumonia, can die.
- often Hx of carrier animal entering herd.
Scoring system for how severely affected calves are by respiratory disease.
Winsconsin Madison Calf Respiratory Scoring Chart.
Dx of enzootic pneumonia.
Hx, CE.
Isolate organism; moribund calf useful.
- Bacteria from RT and ABX sensitivity, BAL, PM.
- Viruses.
- Indirect immunofluorescence on swabs or tissue samples for IBR, BRSV and PI3.
- ELISA for BVD Ag in heparinised blood from animals > 30d old.
- Immunoperoxidase assay for BVD Ag in serum.
Value of swabs?
Detection of Ab, preferably paired samples.
Tx of enzootic pneumonia.
Antimicrobials essential.
- First line ABX:
– oxytetracycline, florfenicol, florfenicol + flunixin (Resflor).
- Licensed but restricted products:
– danofloxacin –> extreme caution.
– marbofloxacin –> extreme caution.
– tulathromycin, gamithromycin, tilmicosin –> vet admin only.
NSAIDs also indicated.
- flunixin, carprofen, ketoprofen, tolfenamic acid, meloxicam, flunixin.
Steroids - dexamethasone – great care.
Nursing care - iso?
Prevention of calf enzootic pneumonia - management.
Risk factors!
- calf source.
- colostrum – ensure quality good, absorption good e.g. in time.
- Housing.
- Temperature.
- Damp/humidity/ventilation/dust.
- Nutrition/water.
- Fear/anxiety/stress.
- Castration/dehorning etc.
- Management.
