Bovine Respiratory Disease DAIRY Flashcards
list some environmental risk factors for BRD in dairy calves
indoor housing, bad ventilation
list some management risk factors for BRD in dairy calves
colostrum management, pre-weaning nutrition and peri-weaning nutrition, biosecurity and biocontainment such as: foot traffic from other areas of the farm, handling of sick calves, group housing of pre-weaned cows
a typical sized dairy calf needs how much colostrum how fast?
200 IgG within 4-6 hours of birth BUT recent work showing this is not enough and 300 is better by 12 hours of age (in 2 feedings)
laryngeal necrosis in adults is usually secondary to
balling gun and drenching injuries
you see a cow with inspiratory dyspnea and excessive salivation. when you look in the mouth you can smell somethin NASTY and you see some cellulitis. what happened here? how will you treat this cow?
laryngeal necrosis/inflammation from balling gun or drenching injury
tx: antibiotics and anti inflammatories, tracheostomy if severe
if extensive, euthanasia is good option
how do CALVES usually get laryngeal infection +/- obstruction?
calf diptheria / “honkers syndrome” / laryngeal necrobacillosis
you see a calf with a foul necrotic odour in it’s breath, the cow is also anorexic, depressed, and has a fever. it honks on inspiration. dx? how will you treat?
calf diptheria–>fusobacterium necrophorum
likely from mucosal trauma from coarse feed or sharp teeth allowing bacteria in
if it progresses, cellulitis, toxemia, and resp distress
treatment: oxytet or fluorfenicil, dexamethasone, tracheostomy for severe cases
what bacteria are usually involved in aspiration pneumonia? how do calves vs adults usually get this?
P. multocida, T. pyogenes, fusobacterium spp
calves: large nipple openings, improper neck position when bottle feeding, chugging pail milk
adults: accidental stomach tube placement
aspiration pneumonia: green to black lungs and fibrinous pleuritis
clinical signs of caudal vena cava thrombosis (CVCT)? how does this happen?
coughing up blood, fever, anemia, hypovolemic shock, acute death, bilateral epistaxsis
inflammatory ulcerative mucosal lesions in the forestomach or abomasum can allow bacterial seeding of the portal circulation, from there emboli can form and lodge into the lungs
usually F. necrophorum, T. pyogenes
poor prognosis
which 2 pathogens are becoming more prominent in dairy cows?
mycoplasma bovis and salmonella dublin
CS of salmonella dublin? why is this bacteria such a problem?
high fever, tachypnea, dyspnea, septicemia, NOT BLOODY DIARRHEA, looks like really bad BRD
antibiotic resistant and zoonotic, high mortality in naive herds, persistent in environment
you are looking at a PM cow and see congested lungs, a swollen liver, enlarged spleen, and red firm lungs
salmonella dublin
best way to detect salmonella dublin carriers?
ELISA test 5-6 weeks post infection in calves
2x ELISA test 2 months apart prior to entry into herd
what is so bad about M bovis?
calves exposed at very young age and shed the bacteria for months, the bacteria lives in the upper airway and comes out during times of stress
