Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Cattle > Single Agent Infectious Diseases > Flashcards

Single Agent Infectious Diseases Flashcards

1
Q

Infection with bovine herpes can turn into what disease?

A

Infectious bovine rhinotracheitis (IBR)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

CS of BoHV infection?

A 
Pyrexia
Dull
Decreased appetite
Fluid discharge from eyes / nose
Sudden decrease in milk production
Pharyngitis
rapid, loud breathing, +/- cough

+/- abortion, embryo death, neurosigns in neonates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Dx of BoHV infection?

acutely sick vs herd

A

Acutely sick animals get direct tests = Best is ocular conjunctival swab
(send that off for PCR, virus isolation, or FAT)
[nasopharyngeal swab and semen used less often]

Herd = serological Ab testing; bulk milk tank test very useful

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Tx of BoHV infection?

A 
NSAIDs
Rest and nursing
Remove from stress
Abx if worried about 2ndry infection
Vaccination of the rest of the herd
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which single agent infectious diseases have vaccinations?

A

BoHV, BVD, Lepto, Salmonellosis,

Johnes can get to import (interferes with TB testing)
Neospora in some countries ( low efficacy)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What types of vaccination are available for BoHV?

And what are they licensed to do?

A

1) Conventional
2) Marker [no glycoprotein E, so no Ab to E - can tell the dif. b/w infection and vaccine]
3) Live-attenuated
4) Killed (inactivated)

Licensed for decreasing amt of shedding during primary infection and reactivation, and decrease severity of clinical signs.

Vaccines DO NOT prevent latent infections or reactivation!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What kind of virus is BoHv and what are the common subtypes?

A 
alpha virus
subtypes =
1.1 (IBR + abortion)
1.2a (reproductive, IPV/IPB, abortion)
1.2b (reproductive, IPV/IPB, NOT a cause of abortion)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the pathogenesis of BoHV?

A

Naive animal -> infection-> (shedding) -> latent infection -> stress -> reactivation and secondary infection -> shedding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How is BoHV shed and spread?

A

Spread by direct contact (mostly)
Respiratory secretions (contact & aerosol, 3-5m)
Venereal (semen, fluids)
+/- indirect spread (fluid on clothing)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what happens to virus during latent infection of BoHV, and what about Ab?

A

Virus is latent in nerve ganglion and has potential to reactivate at any point in life

Ab titer persists! (for both E an B glycoproteins)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What happens during reactivation? What can cause reactivation?

A 
CS rare (b/c Ab to fight it), VIRUS SHEDS!
Stress can cause this, immunosuppression (high dose dex), Lameness, disease, nutritional stress
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe/draw Ab levels @ MDA, primary infection, latent, and reactivation

A

See notes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

In what situations will you get a latent infection w/o any circulating Ab?

A

Seronegative latent carrier

= infections when maternal antibodies present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

If you do a glycoprotein E ELISA on a uninfected cow with a marker vaccine, what will teh result be? [for BoHV]

A

Negative

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

If you do a glycoprotein B ELISA on an uninfected cow with a conventional vaccine, what will the result be? [for BoHV]

A

Positive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

If you do a glycoprotein B ELISA on an uninfected cow with a marker vaccine, what will the result be? [for BoHV]

A

Positive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the 3 main steps to monitoring herd control of IBR?

A

1) set a clear goal
[ex- for non-infected herds, your goal = remain free / for infected but low prevalence, your goal = eliminate from herd / for high prevalence, your goal = prevent spread]

2) coordinate essential components
[bioexclusion, cull/isolate latent infections, regular herd vaccination]

3) monitor progress
[repeat investigative herd testing @ regular intervals]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the 3 main questions to ask when setting your goals for herd control of IBR? and how would you investigate them?

A

1) Is the herd infected? = Hx, bulk tank Ab test
2) How many are infected? = sample proportion to determine prevalence
3) Which ones are infected? = Individual screen tests

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What kind of virus causes BVD?

A

Pestivirus (RNA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the 2 biotypes of BVD?

A

Cytopathic (CP)

Non-cytopathic (NCP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What impact does an initial infection with BVD have on herds?

A 
Decreased fertility
Abortion
Congenital defects
Stunted calves
Immunosuppression
Transient diarrhea in adult naive herds
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is required for a BVD infected cow to get Mucosal disease?

A

The cow must be infected with NCP strain and then Ag-related CP virus

mechanisms = mutation of the NCP strain in PI animal, or superinfection of PI animal by CP virus

ONLY PI ANIMALS GET MUCOSAL DISEASE!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the classic signs in calves of an in-utero infection?

A

wide based stance, nystagmus, shaking as it puts his head down

cerebellar hyperplasia!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How does a PI cow get Mucosal disease?

A

Mucosal disease arises when an immunotolerant PI cow w/ NCP strain already, becomes superinfected with CP strain of same antigen (NCP strain mutation or from env)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What age is Mucosal disease commonly seen?

A

6 mos - 2 years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the consequence of mucosal disease

A

Death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What happens when infected w/ BVD during pregnancy at day 0? (non-immune)

A

Ag + / Ab - (PI CALF!)

PI calf, or early embryonic death, abortion, or fetal stunting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What happens to fetus when infected w/ BVD during middle 3rd of pregnancy? (non-immune cow)

A

Congenital defects, abortion, fetal stunting

after fetal immune system development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What happens when infected w/ BVD during last 3rd of pregnancy? (non-immune cow)

A

Ag - / Ab +

Abortion or fetal stunting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

If an immune cow is infected w/ BVD during pregnancy what will happen to the fetus?

A

nothing

Will still create Ab in colostrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are the CS or Mucosal disease?

A 
Depression, decreased appetite
Salivation
Diarrhea (profuse, watery, foul smelling)
Lacrimation +/- crusting around nose
Decrease BCS
Ulcers - all oropharynx & onto muzzle
Dry, cracked, inflammed rhinarium
Oral pain
Oral flare/flush - redding of MM
Ulcers in interdigital cleft
\+/- dermatitis - scabs/skin crusts
Foul smelling ulcers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Dx of Mucosal disease? (ind. vs herd)

A 
Individual = 
CS (should be enough)
Serology for PI (PI = Ab -, Ag +)
Virus isolation
PM
Herd =
Bulk milk testing*
Ind. animal blood samples
EAR NOTCH SAMPLES
Test bulls & herd replacements (test animals coming in)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What do you do if you find a PI cow?

A

Cull

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Tx for BVD?

A

rapid recovery in a few days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

When ear tag samples come back Ag +, what can this mean?

A

PI or Transient infection

36
Q

If an ear tag sample comes back positive, what do you do?

A

confirmatory testing 3-4 weeks later (to see if transient infection)

37
Q

What test can detect infected calves in the face of maternal-derived Ab?

A

RT-PCR

38
Q

What causes Johne’s?

A

Mycobacterium avium paratuberculosis

39
Q

How do cattle get injected with Johne’s?

A

Oral (feco-oral)
Transplacental
Via milk or colostrum

40
Q

CS in beef vs. dairy for Johne’s?

A

Both have = poor BCS, Decreased fertility
Usually remain bright until terminal stages

Dairy = Decreased milk yield, Increased ICSCC, usually culled for poor performance

Beef = Small calves, Calf ill-thrift, Diarrhea (homogenous, watery, no blood), Peripheral edema (submandibular - bottle jaw)

41
Q

Dx of Johne’s

A

Hx, CS

Diagnostic Tests =
Ab - serum and milk ELISA (most common)
fecal PCR, smear, culture
PM & histopath

ELISA testing = 50% sensitivity, can get many false negatives, 99% specificity, beware after TB TESTING (false positives)

42
Q

What do you have to be wary of with false positives for Johne’s ELISA?

A

TB Testing can lead to false positives

43
Q

What do the colors on a Milk ELISA hx mean?

(blue, red, green, yellow) [Johnes]

A 
Green = low risk (negative quarterly milk testing)
Yellow = 1 + quarterly sample (but take another, b/c possible false +)
Blue = born of high risk cow
Red = high risk, probably cull
44
Q

What is normal screening for Johne’s?

A 
ELISA based
Blood test all animal > 2 years old annually
Milk ELISA test quarterly
Cull any +
Manage + as leper colony (keep separate)
45
Q

How does a farm become “Johnes accredited free”?

A

Get 3x annual clear tests

46
Q

When is PCR testing useful? [Johne’s]

A

In areas of high TB testing

more sensitive, picks up cases that you would miss w/ blood testing

47
Q

What are 5 main steps to Johne’s control in beef herds?

A

1) ID status of breeding cattle
2) Separate into negative and positive groups
3) Biosecurity
4) keep replacements from negative cows
5) Slurry and/or manure management - not on pasture grazed by youngstock, esp. slurry from known positives

48
Q

Tx of Johne’s?

A

NONE!

get + cows off farm ASAP

49
Q

How is Johne’s spread on the farm?

A

Feces, Milk, Transplacental

shared water sources, if a + cow shits in water

50
Q

What management things must be done to control Johnes?

A

Test & cull
Calf rearing, cleanliness, colostrum, replacement milk, pasture/slurry

Vaccination (import, interferes w/ TB testing)

51
Q

Johne’s control in dairy herds?

A

Same as beef, and don’t pool colostrum in herds w/ known Johne’s dz w/ cows w/ unknown/+ tests

Aim = individual calving area, remove calves @ birth, then feed colostrum separately (of calves from + cows)

52
Q

What’s up with the Johne’s vaccination?

A

Import only
Needs approval
Interfere’s with TB testing!!

53
Q

Public health concerns for Leptospirosis?

A

Zoonotic!

54
Q

CS of leptospirosis?

A

Primary infection = NO clinical signs
Pyrexia (41C)

2 syndromes:

1) milk drop syndrome
2) sudden fever / agalactia

All quarters soft & flabby & yellow sections

Abortion (or infertility): delayed 6-12 week post infection once infection isolated to kidneys and uterus.
Tends to affect younger cattle more frequently

55
Q

Dx of Lepto?

A

Bulk milk Ab
Blood Ab (serology) [serial testing, 2 samples a few weeks apart]
Urine: culture difficult, PCR to look for genetic material, dark brown microscopy or FAT to directly visualize

Rapid spike in IgM/G in blood detected by ELISA; rapid peak declines over several weeks still with seropositives

Renal carriage: extended period of shedding >18 months

Detection of Ab after abortion is NOT DIAGNOSTIC!

56
Q

Tx of Lepto?

A

High dose Streptomycin - decreases renal carriage
(ex- pen & strep)

NSAIDs: flunixin, as pyrexic

Fluid therapy: if stopped eating & drinking, and are dehydrated

57
Q

Vx for Lepto? what are its indications?

A

2 licensed vaccines:
to reduce renal carriage and shedding, one has claimed to improve fertility

1) Leptavoid -H
2) Spirovac

58
Q

How is lepto shed? transmitted?

A

Urine mainly
through water sources
semen

Infection through abrasions, MM (so urine splashing is a risk factor)

59
Q

Control of Lepto?

A 
Herd control = 
isolation
muck out straw pen
bull check (semen sample?)
High dose strep - reduce shedding
Be aware of zoontic risk when milking or handling new abortions!
60
Q

CS of Neospora caninum infections?

A

Often NO CS
Abortion is the ONLY CS
(may rarely see weak born/neuro calves from infected calves)

61
Q

What are IMH and FH for Neospora?

A 
IMH = Cows
FH = Dogs

Localize to brain / CNS and muscles as bradyzoites in cattle

62
Q

Dx of Neospora caninum infection?

A

PCR of brain of the aborted fetus
Check the dog; definitive host tricky
Placenta? (prefer fetus)
Limited use for Ab - after abortion

Animals become lifelong carriers and higher risk for abortions (98% offspring infected too) - Ab are produced w/ fluctuating titer

63
Q

Tx for neospora caninum?

A

NONE
cows are not sick (unless RFM, then sick)
Put animal down via gun or euthatal

64
Q

spread of neospora caninum?

A

98% vertical transmission
Horizontal transmission = Oocysts in dog feces
No direct spread cow to cow

65
Q

Herd control for neospora caninum?

A

Cull carriers = what if high prevalence?
Deal with horizontal spread - stop dog eating placenta
Deal with vertical spread - ET (need negative recipients), purchase negative replacements? breed to beef
Public footpaths - info signs regarding dogs spreading disease

66
Q

What causes malignant catarrhal fever?

A

Ovine herpesvirus -2

Alcaphine herpesvirus-1

67
Q

CS for MCF?

A 
Extensive VASCULITIS
Severely sick animal
Pyrexic
Lymphadenopathy
Anorexia
copious mucopurulent oculo-nasal discharge +/- blood
Drooling saliva
Congested sclera vessels
Corneal edema
hypopyon (inflammed cells in anterior chamber - irisitis)
Diffuse oral/nasal ulceration
68
Q

Dx of MCF?

A

Ab in serum or from affected tissues
PCR for AHV in blood or tissue (ex- conjunctival swab)
PM - linear ulceration of esophagus [DDx MD]

69
Q

DDx for MCF?

A

Mucosal disease

Foot and mouth Disease

70
Q

Tx of MCF?

A 
normally fatal (if you see CS)
Some do survive

Euthanasia!
Otherwise supportive therapy; but (almost) always fatal

71
Q

Control for MCF?

A

Avoid contact w/ sheep @ lambing time (b/c of ovine herpesvirus 2)

72
Q

What causes Listeriosis?

A

Listeria monocytogenes

73
Q

pathogenesis for Listeriosis?

A

Invasion through gumline into CN -> septicemia

74
Q

CS for Listeriosis?

A

CN deficits:
circling, head tilt (vestibular), unilateral facial paralysis (ear droop, drooling, off feed)

Less common:
Abortion (more common in sheep)
Neonatal septicemia (think colostrum!)
Spinal abscesses
Mastitis
75
Q

Dx of Listeriosis?

A

Organism is ubiquitous, therefore so are the Ab!
(CAN’T USE SEROLOGY!)

CS
Brain from animal affected, or aborted material & isolation of L. monocytogenes
Lumbosacral CSF tap: increase protein, mild pleocytosis (increased cell count)
Immunofluorescence

76
Q

Tx of Listeriosis

A

Abx!!
[Oxytet, Amoxi]

NSAIDs
Nursing
Fluid therapy
Recovery usually depends on how much residual damage done, can recover quickly once tx initiated

77
Q

Control of Listeriosis

A

Found in feces, soil, decaying herbage/silage - ubiquitous

Care when making silage (avoid soil contamination)
Stop feeding poor quality silage if clinical cases
Ends and top soiled; STOP feeding to youngstock

78
Q

What cause Salmonellosis?

A

Salmonella typhimurium / dublin

79
Q

What parts of the body does salmonella most affect?

A

Intestines & bladder

80
Q

CS of Salmonellosis?

A

CS may be absent
Pyrexia
Abortion
Acute (painful)
NECROTIZING HEMORRHAGIC ENTERITIS (fould smelling, bloody diarrhea) - unlike neospora
Bruxism (teeth grinding)
Osteomyelitis, dry, gangrene, enteritis, septicemia, meningitis, joint ill

81
Q

Dx of Salmonellosis?

A

Ab response detectable by:
SAT (serum agglutination test)
Increasingly being replaced by ELISA

-Detection of Ab after abortion IS NOT DIAGNOSTIC!!

Confirm dx:
Fetus to lab -> stomach contents
culture the feces

82
Q

Tx of Salmonellosis?

A

Fluids
NSAIDs
Abx - Trimethoprim Sulphonamide!, beta lactams, fluoroquinolones

83
Q

Prevention of Salmonellosis?

A

Vaccination - Dublin and typhimurium in one vial

Creates Ab response (serum/colostrum)

84
Q

Control of Salmonellosis?

A

Herd control = isolate the sick animal, vaccinate - target towards breeding seasons, etc. high periods of risk
Reduce fecal contamination of feed
Limit exposure to vermin/birds: control/proofing shed

Other actions:
biosecurity - buying in?
isolation/quarantine - test
Zoonosis - don’t eat crap, clean and disinfect you / clothing before eating

85
Q

Spread of Salmonellosis?

A

Shed in feces therefore mainly fecal-oral
In feed, vet, slurry, rodents, birds

S. dulbin = cattle is maintenance host
S. typhimurium = less, sporadic cases - dose dependent

Cattle (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions