Bovine Respiratory Dz

Question 1

Which lung lobe is affected first?

Answer 1

Accessory {of the right lung}

…then middle

Question 2

How many lobes comprise the bovine lungs?

Answer 2

6

Left: cranial {2 parts:} & caudal
Right: cranial​, middle, caudal, & accessory

Question 3

What abnormal sound might we hear in a cow with allergic rhinitis?

Answer 3

Sneezing

Question 4

What might expiratory grunting on auscultation exam indicate?

Answer 4

thoracic pain

pleuritis & severe pneumonia

Question 5

What might inspiratory ​& expiratory grunting on auscultation exam indicate?

Answer 5

cranial abdominal pain

TRP

Question 6

What upper airway sound would we expect in a case of laryngeal calf diphtheria?

Answer 6

stridor on inspiration
{dec.in cross-sectional area of larynx}

Question 7

What abnormal sound would we expect to hear on auscultation exam if a retropharyngeal abscess is present or some other external pressure on larynx/upper airway?

Answer 7

Snoring!

Question 8

Morphological Description/Diagnosis {MDx}?

Answer 8

Something along the lines of…

caseous material in the nasal passages

Question 9

Based on the characteristics of this pathology, what type of infection are we thinking in general
{bacT, Protozoal, Fungal, Virus?}

Answer 9

URT virus!

Question 10

T or F:
Unilateral nasal obstruction may present as unilateral airflow deficit and respiratory stertor.

Answer 10

• *False;**
• ​respiratory stridor*

Question 11

If both nostrils have reduced airflow,
what do we assume a nasal obstruction is caudal to?

Answer 11

The nasal** **septum!!

*masses localized rostral to the pharynx,
airflow is generally reduced on the side/lesion*

Question 12

What is the best way to assess respiratory rate?

Answer 12

From a distance

Question 13

What does increased inspiratory effort indicate?

Answer 13

upper airway obstruction

Question 14

What does increased expiratory effort indicate?

Answer 14

Lower respiratory dz

Question 15

Why would a cow with a nasal obstruction potentially need a tracheotomy?

Answer 15

If we’re thinking this passageway is obstructed, and the steer is really struggling & going into respiratory distress as we’re trying to get the diagnosis,
the best thing we can do is get them airflow!
If we know the obstruction is above the trachea, we can put a little tracheotomy in there & they can breathe much easier & reduce down the stress happening…

Question 16

What does Laryngeal/Pharyngeal Dysfunction often occur secondary to…?

Answer 16

Chondritis of the laryngeal** **cartilages

*Calf Diphtheria {necrotic pharyngitis} also follows L/P damage;
necrosis is d/t infection w/ Fusobacterium necrophorum*
{also: Arcanobacter (Trueperella) Pyogenes & anaerobic bacT}

**most commonlyoccursthru inappropriate use of oral dosing equipment, stomach tubes, or potentially coarse feedstuffs**

Question 17

What are the 2 common names for Bovine Herpes Virus-1?

Answer 17

• Infectious Bovine Rhinotracheitis {IBR}
• ”Red Nose”

3 Subtypes…

​BHV-1.1: respiratory dz + abortion

BHV-1.2a: genital tract infections {vulvovaginitis}

BHV-1.2b: respiratory dz but no abortion

*All 3 share antigenic properties so vacc provides cross-protection*

Question 18

What’s the general pathophysiology of Bovine Parainfluenza -3 {PI-3} ?

Answer 18

Paramyxoviridae

limited to respiratory tract; can be a primary pathogen, but more significant in 2^oDz

Affects epithelial cells of URT {& occ.as far down as alveoli}

infection = damage to ciliated epithelial cells, mucus layer, & mucocilary transport
→mild bronchitis, bronchiolitis

Question 19

Why would someone not vaccinate their bull calves with
Bovine Respiratory Syncytial Virus?

Answer 19

Because there is some sort of diagnostic test they will do later in a bull’s life, that if you give this vaccine, the titers will interfere w.them…

Question 20

Between what gestation period days do susceptible pregnant cattle become infected with BVDV?

Answer 20

42-125 days

{125 days: typically when immunocompetence happens}

*if they’re infected prior, it becomes “self” & they’re lifelong shedders*

Question 21

What antibiotics should we consider in Retro-/pharyngeal abscess?

Answer 21

Penicillin, ampicillin, oxytetracycline, florfenicol, or ceftiofur

Question 22

T or F:
BHV-1 modified-live vaccines can also produce latency of the vaccination strain. Annual boosters help prevent re-excretion of the virus.

Answer 22

True!

Question 23

You visit a farm where a new bunch of calves have just been transferred to. A few calves about 6 months old have hyperemia of the muzzle, signs of rhinitis, drop in feed intake, and occasional labored breathing. The manager also mentions to you that he’s seen a couple of them with “winter pinkeye.” What’s going on?

Answer 23

BHV-1
hi morbidity, lo mortality

*often sets up env’t for 2^o infection w. M.hemolytica, P.multocida, H.somni, or Mycoplasma spp.*

Question 24

A herd of cattle are showing signs of anorexia, nasal & ocular discharge, increased respiratory rate with tracheal rales. You perform a postmortem, and find mild interstitial pneumonia, intracytoplasmic inclusion bodies in various regions of nasal mucosa. What do you suspect & what should you tell the owner of the farm?

Answer 24

Bovine Parainfluenza - 3 {PI-3}

If uncomplicated, recovery occurs w/in 7 days
& it’s an enveloped virus {susceptible to disinfectants}

Question 25

What vaccine do we use for Bovine Adenovirus?

Answer 25

None available in N.America

Question 26

Bovine Coronavirus has been isolated from respiratory secretions of infected calves, along with….?

Answer 26

BRSV
BVDV
& PI-3 in calves w/ Shipping Fever

*cannot differentiate from other respiratory viruses associated w/BRDC*

Question 27

What’s the preferred antemortem sample for diagnosing Bovine Coronavirus?

Answer 27

nasal swabs
—> Ag-capture ELISA, electron microscopy, PCR

Question 28

How could BRSV have negative effects on reproduction or fetus?

Answer 28

By causing a fever that could result in abortion, that’s it

Question 29

What age bracket does BRSV tend to present?

Answer 29

3-12 month-old calves

infects epithelial cells from nasal mucosa to bronchi including
type II pneumocytes & alveolar macrophages
—> loss of cilia & necrosis of bronchial/bronchiolar epithelial cells

Question 30

What can make diagnosing BRSV difficult?

Answer 30

Both healthy exposed & dz’d cattle will seroconvert
w/no difference in seroconversion rates b/t the 2 groups

Question 31

What are the clinical signs in BRSV?

Answer 31

Mild/severe respiratory dz

• fever
• +/- cough
• nasal/ocular discharge
• pulmonary emphysema
• & occasionally*
• sub-Q emphysema from severely labored breathing
• pneumothorax from ruptured alveoli