Respiratory Disease Cattle Flashcards
What age is majority of resp disease seen in cattle?
YOungsters
WHat temperature indicates a problem in cows/calves?
> 39.5*
What is BRD?
Bovine respiratory disease = Calf pneumonia
What problems does BRD cause?
- painful
- expensive and time consuming to treat
- death
- poor growth rate
- welfare problem
Where do majority of pneumonias affect the lung?
Cranial lobes
What may affect immune status of a young calf?
- environment
- colostrum
ENvironmental factors that affect immunity
- housing
- ventilation
- stocking density
- mixing
- sharing air space with other age groups
- changes in weather
How may wet bedding affect resp?
Ammonia irritating to resp passages
What is the criteria for weaning a calf?
eating 1kg concentrates (per day? check) usually 55-60d
WHen are calves mixed after weaning?
Either immediately after (~ days) or a couple of weeks
What calf factors affect immunity?
- colostrum (6L within 12 hours, first 24 hours most important)
- mixing
- transport
- home bred or purchased
- nutrition
- standard of husbandry
What is CMR?
Calf milk replacer
WHat are the 2 forms of BRD?
- Chronic BRD
- Enzootic = Acute pneumonia
What is seen with enzootic pneumonia?
Groups of calves affected - reduced feed intake - dry/moist cough - ^ resp rate > listen for coughing and look at RR of calves before disturbing them (20-40/min calves, 10-30/min adults)
Individual examination findings - what is the most important parameter?
39.5* (temp most important, temp all calves)
- respiration >40/min
- auscultation both lungs and trachea
- ocular nasal discharge
- conjunctivitis
- gently pinch trachea
> full PE only few calves only
What are other terms for acute pneumonia?
Enzootic or viral
Pathogenesis of enzootic pneumonia?
- 1* pathogen (virus, mycoplasma) damages resp tract
- 2* athogen (bacteria) invades and causes more substantial damage
Does PI3 always cause disease?
Not necessarily, usually present in calf lungs
Does BRSV always cause disease? What is BRSV?
- bovine respiratory syncitial virus
- causes very nasty symptoms and death
Does IBRcause serious clinical signs? Where does this infect?
- Infectious bovine rhinotracheitis (herpes virus 1)
- Infects URT
- v. severe pneumonia
Which pathogen is associated with SARS like disease?
Bovine Coronavirus
How may BVDV be associated with pneumonia? Does BVDV cause diarrhoea?
Does NOT Usually cause diarrhoea!!
- immunosupression
- can worsen concurrent pneumonia infections
Which bacteria may be involved in calf pneumonia?
- Manheimia Haemolytica
- Pasteurella Multocida
- Arcanobacterium pyogenes
- Histophilus somni
Management of an outbreak of calf pneumonia
- treatent
- environment
- PME of dead calves
- ID pathogens
Tx of calf pneumonia?
- attend and do not just dispense Abx over the phone
- if >25% affected -> metaphylaxis (treat whole group)
> ABx (not lots of hard evidence but used most commonly)
> NSAIDs (maybe more effective against the viral component!)
“Tx rules” for calf pneumonia
- Read data sheet
- when to repeat
- Weigh animals
- Human safety (eg. micotil fatal in humans, suicide)
- Meat and milk withdrawal time
- Injection site (sc/im)
- Nuflor may not be used in breeding males
Side effects of long term NSAID uese?
- GIT abomasal damage
- renal failure if dehydrated
WHat samples can be taken to ID pathogens? Which calves do you want to sample?
- calves in early stages of disease
> transtracheal wash
> BAL (virus isolation, bacterial culture and sense)
> Nasopharyngeal swab (virus FAT, culture sense)
> serology (paired samples clotted, 2-3 weeks inbetween, beware MDA present in young feacal exam (salmonella, parasites)
What can be checked at PM?
BRD
- specific diagnostics on lung
- Bullae may be ppresent
What does IBR (BHV1) cause?
- Infectious Bovine Rhinotracheitis
- Bovine Herpes Virus 1 (BHV 1)
> pyrexia
> conjunctivitis
> coughing
> tracheitis (auscultate trachea)
> URTI
*NB: BHV1.2 - gential form -> vulvovaginitis etc.
What clinical synromes may IBR cause?
- resp disesae (rhinitis, tracheitis, conjunctivitis)
- ocular form
- encephalitis (young)
- abortion (sporadic)
- repro failure
> latent infection
How does BHV1 (IBR) become latent?
Resides in trigeminal ganglion (CN V)
Stress -> recrudescence
Treatment of IBR
NSAIDs
4 methods of IBR control
- state of the herd (bulk milk Ab or sample few beef; monitor abortions; pneumonia cases)
- biosecurity
- vaccination (work well; before or after natural exposure prevent respiratory disease, v shedding, prevent abortion)
- eradication
What 2 types of IBR vaccines are available? What new type of vaccine is available for IBR?
- LIve attenuated vaccines (can become latent in the trigeminal ganglion, ^ risk, only 1 or 2 injections needed)
- Dead killed inactivated, less effective, more boosters needed
> MArker vaccine (DIVA: differentiate infected from vax animals)
> Intranasal vax quite good for local immunity
What is the most common cause of aspiration pneumonia?
Stomach tubing wrong
What pathogen is associated with calf diptheria? WHat else is this known as? CLinical signs and PE?
- necrotic laryngitis
> fusobacterium necrophorum - foul smelling necrotic lesions, can be caused by food trapped between teeth and buccal mucosa
- swollen cheeks
- ^ respiratory noise
- respond well to B lactams (G+ organism)
- auscultate over larynx and trachea (maybe not lungs)
Causes of calf diptheria?
- poor stomach tubing technique
- > mucosal injury calves 1-4 months
- poor hygeine of feeeding equipment
- course feeds
Tx calf diptheria
Abx
- tracheostomy or surery to debride
Which breeds are susceptible to diptheria?
Texel rams and belgian blues
What is the most common disease of older (1-2yo calves)
Shipping fever (transit fever/pasteurellosis)
esp seen in feedlots in america
- signs shown 10-14d after transport
What predisposes to shipping fever (pastuerellosis)?
- transport, mixing, temperature, stress
Clinical signs/presentation of shipping fever?
- sudden onset pyrexia, anorexia, ^ RR, cough, ^ resp noise, grunting
- may be found dead -> PM!
Pathogens involved with shipping fever?
Mouth commensals
- Manheimia haemolytica
- Pastuerella Multocida
- Other viuses and bacteria
Pathogenesis of shipping fever? Problems?
- Severe acute bronchopneumonia cranio-ventral lobes
- can become chronic
- welfare problem
- economic loss due to v growth
How does respiratory disease manifest differently in adults cf. calves?
One off rather than disease outbreak
What is fog fever also known as? What is it?
- Acute Bovine Pulmonary Oedema and Emphysema
- Atypical Interstitial Pneumonia
> Non-infectious disease associated with cattle grazing lush pastures in Autumn
> Older cattle >2yo
> up to 50% group can be affected
Pathogensis of fog fever?
- L-tryptophan -> 3-methylindole in rumen -> pulmonary toxicity and damage
Clinical signs of fog fever
- sidden onset
- group affected
- very severe respiratory distress, varies between individuals
- frothing at mouth
- distress or death when attempting to move
- subcut emphysema over back and thorax
First action if fog fever noticed? Tx? Prognosis?
Get the animals off the pasture - corticosteroids/ NSAIDs - diuretics * NB: corticosteroids in pregnant cattle -> abortion Prognosis = guarded
Prevention of fog fever
- restrict access to lush pastures
- strip grazing
- feed hay before and during intiial period of grazing new pasture
- avoid over fertilising pasture
What is bovine farmers lung?
Hypersensitivity to moulds
- usually mouldy or poorly made hay
- poor ventilation
> acute with mouth breathing, coughing, drop in milk yield
> chronic insidious with weight loss and coughing
*Farmer may have it aswell!
