Upper Resp. Disease in Large Animals

Question 1

Equine Viral Rhinopneumonitis (EVR)

Answer 1

From Equine herpes virus 1 (EHV1)
Causes mild resp. disease in weaning foals and racehorses (stress) and abortion
Predispose to secondary bacterial infection

Question 2

Equine Influenza Virus

Answer 2

Caused by Type A infleunza virus (orthomyxovirus)
Causes fever, conjunctivitis and nasal discharge

Question 3

What can secondary bacterial infections from equine influenza virus cause?

Answer 3

Bronchointerstitial pneumonia and nasal discharge

Question 4

Fatal adenovirus infection

Answer 4

In immunocompromised foals
Arabians + immunodeficiency disease (CID)

Question 5

Strangles

Answer 5

Streptococcus equi equi
Causes suppurative rhinitis and lymphadentitis (mandibular and retropharyngeal)

Question 6

Bastard strangles

Answer 6

Occasional hematogenous dissemination to internal organs

Question 7

Common sequelae of strangles

Answer 7

Bronchopneumonia due to aspiration of exudate
Laryngeal hemiplegia (roaring)
Facial paralysis
Purpura hemorrhagica

Question 8

Streptococcus

Answer 8

Gram +, non spore forming, in short cocci or chains

Question 9

Guttural pouch

Answer 9

Ventral dilation of Eustachian (auditory) tubes
Unknown function (thermoregulation ?)

Question 10

Guttural pouch empyema

Answer 10

Pus filled pouch
Ascending bacterial infection from S. equi

Question 11

GP mycosis

Answer 11

Aspergillus spp
Thrombosis/ rupture of carotid artery is common sequela
Epistaxis, thromboembolism to CNS

Question 12

GP tympany

Answer 12

Accumulation of air in the GP
Genetic predisposition in Arabians (foals)

Question 13

Infectious Bovine Rhinotracheitis (IBR/ Rednose)

Answer 13

Caused by Bovine Herpes 1 (BH1)
Synergizes with Manheimia haemolytica to produce pneumonia
Intranuclear IBs

Question 14

CS of IBR

Answer 14

Abortion, systemic infections in calves and infectious pustulae vulvovaginitis (IPV)
Severe hyperemia and focal necrosis of resp. mucosa

Question 15

Calf Diphtheria

Answer 15

Necrotic laryngitis and laryngeal necrobacillosis
Fusobacterium necrophorum
Common in feedlot cattle with other diseases

Question 16

Predisposing factors of calf diphtheria

Answer 16

Traumatic injury**
Nutritional deficiencies
Unsanitary housing
Viral infections
Bacterial infection

Question 17

CS of calf diphtheria

Answer 17

Anorexia, pyrexia, loud wheezing, dyspnea, protrusion of the tongue, ptyalism, depression, halitosis, dysphagia

Question 18

Fusobacterium

Answer 18

Gram-
Non-spore forming anaerobe
Seen in long filaments, short elements or cocci

Question 19

Lesions of calf diphtheria

Answer 19

In arytenoid cartilages
Well-demarcated, dry, yellow-grey, thick-crusted, necrotic areas
Deep ulceration

Question 20

Histopathology of calf diphtheria

Answer 20

Large necrotic folci borded by hyperemia
Granulation tissue, leukocytes (chronic)
Bacterial (secondary)

Question 21

Severe cases of calf diphtheria

Answer 21

Aspiration pneumonia
Death due to toxemia

Question 22

Oestrus Ovis

Answer 22

Oestrus ovis larval infection or Sheep Nose Bot
Common cause of sinusitis in sheep (nasal cavity and paranasal sinuses)

Question 23

CS of Sheep Nose Bot

Answer 23

Run and gather in circles with their heads together to avoid flies (Not CNS!!)
Nasal discharge and sneezing

Question 24

Severe oestrus ovis infection

Answer 24

Thickening of nasal mucosa and mucopurulent discharge impairs respiration
Larvae dies in sinuses → septic sinusitis and goes to brain

Question 25

Caprine upper resp. disease

Answer 25

P. multocida or M. haemolytica (gram - cocobacilli)
Mild, serous to catarrhal to mucopurulent rhinitis