Changes

***Neoplasia

***Neoplasia

====Viral infections====

====Viral infections====

****Herpesviruses

Herpesviruses

*****Bovine herpesvirus -1

*Bovine herpesvirus -1

******Causes Infectious bovine rhinotracheitis (IBR)

**Causes Infectious bovine rhinotracheitis (IBR)

******Highly infectious URT disease of cattle  

**Highly infectious URT disease of cattle  

******High morbidity, low mortality

**High morbidity, low mortality

******Aerosol transmission - requires close contact between animals

**Aerosol transmission - requires close contact between animals

******BHV-1 infects the respiratory mucosal epithelial cells (intranuclear inclusion eosinophilic inclusion bodies)from nasal mucosa down to bronchioles

**BHV-1 infects the respiratory mucosal epithelial cells (intranuclear inclusion eosinophilic inclusion bodies)from nasal mucosa down to bronchioles

*******leading to neutrophilic inflammation of varying severity.... serous -> catarrhal -> purulent nasal discharge, sneezing, coughing.

***leading to neutrophilic inflammation of varying severity.... serous -> catarrhal -> purulent nasal discharge, sneezing, coughing.

*******with secondary bacterial infection (eg: Pasturella spp., Mycoplasma spp., Fusobacterium necrophorum) can lead to fibrinous to necrotizing inflammation; mucosal sloughing, ulceration... pyrexia, dyspnoea ... inhalation pneumonia... death.

***with secondary bacterial infection (eg: Pasturella spp., Mycoplasma spp., Fusobacterium necrophorum) can lead to fibrinous to necrotizing inflammation; mucosal sloughing, ulceration... pyrexia, dyspnoea ... inhalation pneumonia... death.

******Clinical signs include coughing, discharge, lacrimation, and increased respiratory rate.

**Clinical signs include coughing, discharge, lacrimation, and increased respiratory rate.

******Clinical disease most severe in young calves - can develop mucosal ulcerative lesions in the oesophagus and forestomachs and viraemia with multiorgan infection.

**Clinical disease most severe in young calves - can develop mucosal ulcerative lesions in the oesophagus and forestomachs and viraemia with multiorgan infection.

******Cause of abortion >5 months of gestation  

**Cause of abortion >5 months of gestation  

*****Cytomegaloviruses  

*Cytomegaloviruses  

******Porcine cytomegalovirus

**Porcine cytomegalovirus

*******Causes Inclusion body rhinitis  

***Causes Inclusion body rhinitis  

*******Disease of suckling piglets 1-5 wks of age

****Disease of suckling piglets 1-5 wks of age

*******Clinical signs: those associated with acute/subacute rhinitis (ie: serous nasal discharge, progressing to catarrhal or purulent discharge with time and secondary bacterial infections; sneezing; pyrexia)

****Clinical signs: those associated with acute/subacute rhinitis (ie: serous nasal discharge, progressing to catarrhal or purulent discharge with time and secondary bacterial infections; sneezing; pyrexia)

*******Morbitity high, mortality low

****Morbitity high, mortality low

*******Histology: large basophilic intranuclear inclusion bodies in the nasal and sinus respiratory epithelium with lymphocytic infiltration of the mucosa.

****Histology: large basophilic intranuclear inclusion bodies in the nasal and sinus respiratory epithelium with lymphocytic infiltration of the mucosa.

*******Can develop viraemic stage, with inclusions in other organs eg: renal tubular epithelium. Piglets can die during this phase.

****Can develop viraemic stage, with inclusions in other organs eg: renal tubular epithelium. Piglets can die during this phase.

*****Equine herpesvirus - 1, 4

*Equine herpesvirus - 1, 4

*****Feline herpesvirus -1

*Feline herpesvirus -1

******One of the causes of Feline viral rhinotracheitis

**One of the causes of Feline viral rhinotracheitis

******Viruses and bacteria are involved in the complex. The most frequent aetiologic agent is FHV-1, and less frequently feline calicivirus and/or ''Chlamydophia psittac''i (NB: previously called Chlamydia psittaci var felis)

***Viruses and bacteria are involved in the complex. The most frequent aetiologic agent is FHV-1, and less frequently feline calicivirus and/or ''Chlamydophia psittac''i (NB: previously called Chlamydia psittaci var felis)

******All three agents infect URT respiratory epithelium, although FHV-1 has the highest affinity for this epithelium

***All three agents infect URT respiratory epithelium, although FHV-1 has the highest affinity for this epithelium

******Feline calicivirus more frequently infects the oral mucosa -> ulcerative stomatitis

***Feline calicivirus more frequently infects the oral mucosa -> ulcerative stomatitis

******C.psittaci more frequently infects the conjunctival epithelium -> chronic conjunctivitis

***C.psittaci more frequently infects the conjunctival epithelium -> chronic conjunctivitis

******Infection of the respiratory epithelium by FHV-1 results in a typical neutrophilic rhinitis with intraepitheial intranuclear eosinophilic inclusion bodies, with expected clinical signs

***Infection of the respiratory epithelium by FHV-1 results in a typical neutrophilic rhinitis with intraepitheial intranuclear eosinophilic inclusion bodies, with expected clinical signs

******Resolution of clinical signs usually occurs by 7-14 days.

***Resolution of clinical signs usually occurs by 7-14 days.

******FHV-1 remains latent in the trigeminal ganglion, and can reactivate at times of stress. Can infect the cornea -> ulcerative keratitis.

***FHV-1 remains latent in the trigeminal ganglion, and can reactivate at times of stress. Can infect the cornea -> ulcerative keratitis.

******Occasional mortality in kitten or immunocompromised animals usually associated with secondary bacterial infection.

***Occasional mortality in kitten or immunocompromised animals usually associated with secondary bacterial infection.

***Bacterial infections  

====Bacterial infections====

****Pasturella multocida

****Pasturella multocida

*****Atrophic rhinitis in pigs

*****Atrophic rhinitis in pigs