Lab 3.6 Cases

Question 1

what virus causes similar clinical signs as feline calicivirus

Answer 1

Feline herpesvirus

Question 2

How sure are we that calicivirus is the ONLY pathogen playing a role in this shelter outbreak?

Answer 2

we cant be sure without testing

Question 3

what labs can you do to confirm feline calicivirus

Answer 3

• What lab tests could be done?
• Antigen detection: RT-PCR, virus isolation, electron microscopy
• Samples?
• Nasal, ocular swabs, gingival, pharyngeal swabs
  Ideal: bronchoalveolar lavage (BAL), transtracheal wash (TTW)
• PCR panels for feline respiratory diseases usually includes: Feline
  calicivirus, Feline herpesvirus, Bordetella bronchiseptica, Mycoplasma felis,
  Chlamydophila felis,

Question 4

Suggestions to the shelter to control/prevent viral diseases (5)

Answer 4

-Quarantine new arrivals
-Vaccinate upon arrival
-Reduce stocking density if possible
-Improve hygiene = Recovered cats can shed for a long time and can be spread by BOTH aerosol transmission or fomites
-Isolate/quarantine sick animals

Question 5

what disease would you suspect based on the following clinical signs?

-Stillbirths, mummified fetuses, premature farrowing,
-Respiratory coughing, anorexia

Answer 5

PRRS

Question 6

what disease would you suspect based on the following clinical signs?

-Infertility, SMEDI; less respiratory

Answer 6

Swine parvovirus

Question 7

what disease would you suspect based on the following clinical signs?

-Loss of condition, respiratory disease
-Decreased reproductive performance, late term abortion, stillbirth

Answer 7

Porcine circovirus 2 (PCV2): Porcine multisystemic wasting syndrome

Question 8

what disease would you suspect based on the following clinical signs?

-Causes mucopurulent rhinitis in 1-5 week old pigs
-infection of naïve, pregnant sows can cause fetal mummification, still births, neonatal deaths, failure of piglets to thrive

Answer 8

Inclusion body rhinitis (Suid herpesvirus 2)

Question 9

what disease would you suspect based on the following clinical signs?

-Depression, fever, anorexia, coughing, weakness

Answer 9

Swine influenza virus

Question 10

what is one test that can help confirm PRRS?

Answer 10

IHC

Question 11

what are lungs: Red, rubbery, that do not collapse consistent with

Answer 11

interstitial pneumonia

Question 12

what is the most economically important disease for swine producers

Answer 12

PRRS

Question 13

what happens with the spread of PRRS in a naive herd vs endemic herd

Answer 13

-In naive herd: infection spreads slowly causing variable degrees of disease and death
-In an endemically infected herd: infection is often subclinical

Question 14

details surrounding PRRS virus

Answer 14

-Virus is maintained in a population indefinitely by asymptomatic swine who can shed the virus for up to 3-5 months
-Greatest losses are seen in herds experiencing other concurrent infections
-Virus destroys pulmonary alveolar macrophages = risk of secondary bacterial pneumonia
-Virus survives at low temperatures, so epidemic spread is quite efficient in the winter months
-Virus transmission is by direct contact, airborne and via semen

Question 15

what family is the PRRS virus part of

Answer 15

ssRNA, enveloped virus in the Arteriviridae family

Question 16

how does PRRS infection persist on an individual farm

Answer 16

-Persistent infection of individual animals
-Continual outside additions to farm
population

Question 17

are there long term consequences of PRRS infection in a herd? (3)

Answer 17

-PRRS within a herd has variable long-term outcomes in terms of disease severity and production losses
-Secondary opportunistic bacterial infections/ ubiquitous organisms that are normally present in the environment
-Coinfection with Porcine Circovirus Type 2 (PCV-2) can cause more severe lesions - severe clinical presentations and pulmonary lesions compared to either infection alone

Question 18

control of PRRS (4)

Answer 18

-No single effective control strategy
-Often goal is to create a “PRRS stable” farm through intentional exposure of entire stock (before breeding)
-Vaccination: commercial modified live PRRSV vaccine (IM) and inactivated vaccines exist; efficacy is variable
-Elimination on individual farm very difficult due to long shedding period,
asymptomatic carriers, and extreme biosecurity measures required for
maintenance (including massive initial depopulation)