cattle respiratory disease Flashcards
what are the 3 components causing bovine respiratory disease?
host
environment
pathogen
how do you check a calf has adequate colostrum intake?
blood at 2-7do and put serum on refractometer - over 5.5 = healthy calf
what is shipping fever?
seen in older calves
10-30 d after transport or after stress
- URT commensals but become lung pathogens
-sudden pyrexia, reduced feed intake, tachypnoea, cough, grunt, sudden death
what pathogens can contribute to bovine respiratory disease complex?
parainfluenza 3 bovine resp syncytial virus IBR (BHV1) coronavirus secondary - mannheimia, pasturella, arcanobacterium, histophilus somni
what is acute enzootic pneumonia?
seen in groups of calves
dull, cough
worry if temp over 40, rr over 40, discharge or conjuctivitis
what bovine resp pathogen can become latent and where?
IBR - bovine herpesvirus 1 - in trigeminal ganglia
- will be sero negative for it
what is a non-infectious calf pneumonia?
calf diptheria
- fusobacterium necrophorum
what can cause calf diptheria?
mucosal injury from sharp teeth
unhygienic stomach tubes
coarse feed
food trapped between teeth and buccal mucosa
what are the signs of calf diptheria?
excessive salivation foul breath swollen cheeks abscesses increased resp noise
what is fog fever?
see signs within 2w of moving to lush autumn pasture
- resp distress, froth, subq emphysema over back and thorax
- guarded prognosis
- remove from pasture, give NSAIDs and diuretics
what is bovine farmers lung?
hypersensitivity after inhaling mould allergens
- mouth breathing, cough, low yield, wt loss
how can you manage bovine respiratory disease complex?
abx and nsaids PM any BAL nasophargyngeal swabs for fluro AB test for IBR paired serology (beware of MDA/vax) herd milk/blood status IBR/BRSV / PI3 vax
what is the name of bovine parasitic bronchitis?
dictyocaulus viviparus
husk
what are some control strategies for bovine lungworm?
huskvac vax (vax 2x 4 w apart and turnout 2 w later) strategic anthelmintic dosing - ivermecting, fenbendazole, oxbendazole, ivermectin (3,8,13 w), doramectin (0,8 w)
how is BHV virulent?
viral inclusion bodies
how is BRSV virulent?
large syncytial cells
what is the pathogenesis of BHV?
kill cilia
fibrinous laryngitis and tracheitis
how is mannheimia haemolytica classified?
oxidase positive
makes a leukotoxin
b haemolytic
what does mannheimia do?
- fibrinous epizootic bronchopneumonia in cattle
- pasteurellosis in sheep
- destroys BV so get necrosis, oedema and fibrin in pleural cavity
- mastitis
what does pasteurella trehalosii cause?
septicaemic in older lambs
What is histophilus somni and where is it normally found?
G-ve rod
genital tract and sometimes URT
what does histophilus somni cause?
- death in young calves
- acute thromboembolic meningoecephalitis
- pneumonia
- myocarditis
How is bovine TB classified?
G+ve mycobacteria
strict aerobes
resists intracellular killing
what does bovine TB cause?
- chronic and fatal pneumonia and wasting
- granulomatous pneumonia and lymphadenitis
- dystrophic mineralisation
