Infectious Agents Of Bdrc

Front 1

What is the causative agent of IBR (infectious bovine rhinotracheitis)?

Back 1

Bovine herpes 1 (BHV-1)

Front 2

can BHV-1 be latent?

Back 2

YES

Front 3

Can a bovid shed BHV1 w/o having CxS?

Back 3

yes

Front 4

Where is BHV shed into?

Back 4

Secretions from the respiratory tract, ocular, and genitalia

Front 5

Can the vaccine cause a transmittable infxn?

Back 5

YES - MLV can.

Front 6

What ways do the viral pathogens lend to 2º infxn

Back 6

They cause: mucosal damage, impaired mucocillary clearance, disrupt secretion of IgA, and suppress pulmonary/general immunity.

Front 7

What disease looks like IBR but is massively bad!

Back 7

MCF

Front 8

What groups of cattle are most likely to express clinical disease with BHV-1?

Back 8

Those that are intensively managed -- so dairy>beef. NN calves get a pneumonia and severe dz.

Front 9

Where does BHV1 replicate in the respiratory tract?

Back 9

upper respiratory epithelium (causes that ciliary loss!!!) Can also lead to a viral pneumonia (compared to bacterial) and a conjunctivitis. SYSEMIC IMMUNOSUPPRESSION.

Front 10

What other weird thing can IBR/BHV1 cause in the eyes

Back 10

Corneal edema

Front 11

How long is the incubation with BHV1

Back 11

2-6 days

Front 12

What is the morbidity of IBR?

Back 12

20-30%

Front 13

What are some clinical signs of IBR?

Back 13

Tachypnea, dyspnea, coughing. Inappetance, agalactia, nasal hyperemia/necrosis/crusting--WHITE NASAL PLAQUES. Abortion up to 100d post exposure.

Front 14

How do we diagnose BHV/IBR?

Back 14

Necropsy

VI on nasal, conjunctival swabs

IFA: tissue or mucosal scrape

Paired serum samples (need that 4x rise in titer)

PCR for viral DNA -- there are panels for multiple agents.

Front 15

How do we control IBR?

Back 15

Ensure PT (protection for 4-6 mo), vaccination for clinical DISEASE (not infxn) -- either the bacterin (killed) IM or the MLV (IN, IM)

Front 16

What benefits does the MLV vaccine for IBR have?

Back 16

Rapid response (48-72 hours), stronger/durable immunity.

Front 17

What are the disadvantages to the MLV IBR vacc?

Back 17

Promotion of abortion, latent infxn and virus transmission/disease in recipient.

Front 18

Why do we worry about parainfluenza?

Back 18

It moves through calves FAST and promotes 2º infection

Front 19

What are some of the management things that lend to the spread of PI3?

Back 19

dense stocking of susceptible cattle with close contact.

Front 20

Can we vaccinate for PI3?

Back 20

YES

Front 21

Which disease is caused by an RNA virus that causes syncytium formation in the tissue culture?

Back 21

Bovine respiraotry syncytial virus.

Front 22

Is BRSV common in the US?

Back 22

Yes, there is a 60-80% serologic prevalence in the US

Front 23

What age group do we see outbreaks of BRSV in?

Back 23

ages 2-4 mo - when they are losing their passive immunity, are co mingling more.

Front 24

What type of role does BRSV play in the BDRC?

Back 24

HIGH -- there is a high prevalence, with an infection of LRT and impairing defenses.

Front 25

Besides playing a role in BRDC, what else can BRSV cause?

Back 25

Bronchitis, bacterial pneumonia, acute respiratory distress (ARDS) w/ edema and emphysema.

Front 26

What is a weird thing to check for in a BRSV suspect case?

Back 26

SQ emphysema in the BACK

Front 27

How is BRSV spread?

Back 27

Aerosols.

Front 28

How soon do clinical signs appear of BRSV in an exposed animals?

Back 28

3-7 days

Front 29

How do we diagnose BRSV?

Back 29

Hx

CxS (incl that SQ emphysema)

Necropsy -- interstitial pneumonia

Respiratory fluid -- Fluorescent AnB, Immunohisto or PCR***

Front 30

How do we control BRSV?

Back 30

Ensure passive immunity, vaccination (MLV or killed) of those > 6 mo or on feedlot, those prior to breeding and calves 1-3 mo on problem farms.

Front 31

Is BVDV involved in BDRC?

Back 31

YES -- promotion/permission of 2º bacterial infection

Front 32

Which bacteria does BVDV act in syngerism with to cause BDRC?

Back 32

M. haemolytica, BHV1, BRSV

Front 33

What are some bacterial agents of BDRC?

Back 33

M. haemolytica, P. multocida, H. somnus

Front 34

Where do the bacterial agents of BDRC usually live?

Back 34

nasopharynx of normal cattle ---- NOT LUNG

Front 35

Which mycoplasma are associated with BDRC?

Back 35

m. bovis and m dispar.

Front 36

Do we see mycoplasma on it's own causing BDRC?

Back 36

No -- usually in conjunction w/ other pathogens.

Front 37

Are mycoplasma easy to culture?

Back 37

Nope.

Front 38

What is the main action and power that mycoplasma have in BDRC -

Back 38

They cause a mild pneumonia, but they act more as immune suppressors, compromisers-- allowing in other bacteria (so they are kind of like viruses)

Front 39

Which bacteria is the greatest cause of mortality in northern cattle feedlots?

Back 39

M. haemolyticum

Front 40

Which serotype of M. hemolytic is most common with pneumonia?

Back 40

Serotype A1 (like the steak sauce)

Front 41

How long does it take for CxS to show up for M. haemolyticum?

Back 41

Pneumonia presents within 1st 3 weeks at the feedlot.

Front 42

Which bacterial pathogen of BDRC causes enzootic pneumonia in calves?

Back 42

P. multocida.

Front 43

what does disease from P. multocida indicate (as far as inciting issues?)

Back 43

Management problems - poor ventilation/excessive ammonia, and FPT

Front 44

What does H. somni do in cattle (which systems)?

Back 44

repro, respiratory (pneumonia, laryngitis, tracheitis), septicemia (so meningitis, polyarthritis, myocarditis, pleuritis, pericarditis)

Front 45

Where do asymptomatic carriers of H. somni carry bacteria?

Back 45

urogential and URT

Front 46

How many of those infx'd with H. somni are symptomatic carriers

Back 46

25%

Front 47

How is H. somni spread?

Back 47

Animal to animal contact -- feedlots!!!

Front 48

What is a risk if your feedlot heifer has a LOW titer increase when they get to the feedlot?

Back 48

increased risk for fatal disease

Front 49

What ages and how fast are cattle affected by H. somni?

Back 49

6-8 months old and within 3-5 weeks of getting to the feedlot (esp if they came in w/ a low titer)

Front 50

What types of diseases do we see in those with H somni at the feedlot?

Back 50

Neuro disease, bronchopneumonia, myocarditis.

Polysynovitis esp in the stifle (w/ mycoplasma co-infxn)

Front 51

What kinds of things will contribute to disease emergence?

Back 51

Stress, viruses and mycoplasma infxn, sale barn situation (co mingling), increase in high grain rations, feed/water del, poor ventilation, bad weather

Front 52

How do we diagnose BRDC?

Back 52

PE - temperature, PCR panels for respiratory viruses, bacterial cultures, post mortem lesions (many are characteristic for disease)

Front 53

What are we going to treat BRDC w/? Remember that these animals are going into the human food chain

Back 53

Best: early and aggressive, short acting abx

--ceftiofur, Baytril, oxytet, PenG, Tylan

Front 54

What is special about enrofloxacin?

Back 54

It is labelled for pneumonia ONLY-- extra label use is ILLEGAL

Front 55

What are some long acting drugs we can use?

Back 55

Excede (ceftiofur), Danofloxacin, florfenicol, Tulathromycin, Oxytet

Front 56

Where should we look to see about withdrawal time?

Back 56

FARAD.org

Front 57

What are some prohibited drugs?

Back 57

Chloramphenicol, clenbuterol, dipyrone, vancomycin, metronidazole, nitrofurans

Front 58

Which anti-inflammatory cannot be used in any dairy cattle > 20mo?

Back 58

Phenylbutazone

Front 59

Which drugs are restricted to labelled use only?

Back 59

Ceftiofur, fluoroquinolones, feeds and sulfadimethoxine

Front 60

How can we control BDRC?

Back 60

Preconditioning - vaccines, wean 2 weeks prior d

--limit stress while transporting, limit commingling.

Front 61

What are some feedlot management strategies that can help control BDRC?

Back 61

Rest for 12-14 hours post transport, no holding > 36 hours, temp sort, minimize mixing, don't start grain right away.

Front 62

What the hell is metaphylaxis?

Back 62

long acting abx at entry to feedlot

Front 63

What bacterium is hit with metaphylaxis at feedlots?

Back 63

M haemolyticum.

Front 64

When we are treating for mass outbreaks, what form of medication are we giving?

Back 64

Injectable.

Front 65

What do we vaccinate for?

Back 65

BVDV, BRSV, PI3, BHV1

Front 66

Which vacc are rec'd for bacterial infxn?

Back 66

Live or MLV (cannot be used w/ abx and there is a risk of disseminated infxn)

Front 67

What causes venocaval thrombosis?

Back 67

multifocal abscessation of the lungs from septic thromboembolism

Front 68

what is the most likely agent in VCT?

Back 68

F. necrophorum.

Front 69

What can large emboli cause clinically in VCT?

Back 69

The large amount of restriction of blood flow -- dyspnea, hypoxia and death.

Front 70

What do the smaller emboli cause in VCT?

Back 70

lodging in arterioles == abscess === erosion of vessels -- blood loss!!!

Front 71

How can we prevent VCT?

Back 71

slow adaptation to high grain ration, aBx feed through to prevent hepatic abscesses.