Changes

***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

**Pigs aged 4-12 weeks old show clinical signs

*****Pigs aged 4-12 weeks old show clinical signs

**Catarrhal nasal discharge (due to an acute rhinitis),  sneezing, coughing, can progress to dyspnoea and anorexia.

*****Catarrhal nasal discharge (due to an acute rhinitis),  sneezing, coughing, can progress to dyspnoea and anorexia.

**Shortening and distortion of snout, secondary to nasal turbinate bone loss (histological evidence of osteolysis)

*****Shortening and distortion of snout, secondary to nasal turbinate bone loss (histological evidence of osteolysis)

**2 forms of the disease

*****2 forms of the disease

**'Progressive' atrophic rhinitis

******'Progressive' atrophic rhinitis

**Due to infection of the nasal turbinates by P.multocida strains carrying the toxA gene that encodes for an osteolytic toxin. P.multocida adheres poorly to mucous membranes, and therefore requires a predisposing nasal insult to assist colonisation eg: co-infection with B.bronchoseptica; or Porcine cytomegalovirus (inclusion body rhinitis)

*******Due to infection of the nasal turbinates by P.multocida strains carrying the toxA gene that encodes for an osteolytic toxin. P.multocida adheres poorly to mucous membranes, and therefore requires a predisposing nasal insult to assist colonisation eg: co-infection with B.bronchoseptica; or Porcine cytomegalovirus (inclusion body rhinitis)

**Turbinate bone atrophy is permanent and progressive

*******Turbinate bone atrophy is permanent and progressive

**'Non-progressive' atrophic rhinitis

******'Non-progressive' atrophic rhinitis

**Due to infection of the nasal turbinates by Bordatella bronchoseptica strains alone, that carry a gene that encodes for a dermonecrotic toxin.

*******Due to infection of the nasal turbinates by Bordatella bronchoseptica strains alone, that carry a gene that encodes for a dermonecrotic toxin.

**Turbinate bone can regenerate by the time of slaughter

*******Turbinate bone can regenerate by the time of slaughter

**'Snuffles' in rabbits

*****'Snuffles' in rabbits

**Most often P.multocida and/or B.bronchoseptica infection of the nasal mucosa

******Most often P.multocida and/or B.bronchoseptica infection of the nasal mucosa

**Clinical signs (nasal discharge, sneezing) result from an acute to chronic rhinitis.  

******Clinical signs (nasal discharge, sneezing) result from an acute to chronic rhinitis.  

**Streptococcus equi  

****Streptococcus equi  

**Streptococcus equi subsp. equi

*****Streptococcus equi subsp. equi

**Cause of 'Strangles' in horses

*****Cause of 'Strangles' in horses

**Infection with Streptococcus equi occurs after contact with contaminated feed, water bowls or an infected carrier horse

*****Infection with Streptococcus equi occurs after contact with contaminated feed, water bowls or an infected carrier horse

**Organism remains viable in environment for months

*****Organism remains viable in environment for months

**Possibility of other sources of infection - in pharynx of in-contact dogs?

*****Possibility of other sources of infection - in pharynx of in-contact dogs?

**Colonisation of nasopharynx causing:

*****Colonisation of nasopharynx causing:

**Chronic purulent rhinitis, sinusitis, eustachitis

*****Chronic purulent rhinitis, sinusitis, eustachitis

**Can progress to development of nodular masses in the guttural pouch consisting of inspissated pus and viable bacteria (guttural pouch empyema) - 'carrier' state

*****Can progress to development of nodular masses in the guttural pouch consisting of inspissated pus and viable bacteria (guttural pouch empyema) - 'carrier' state

** Regional suppurative lymphadenitis - can rupture onto skin of neck

*****Regional suppurative lymphadenitis - can rupture onto skin of neck

**Bacteraemia with abscess formation in other organs (eg: liver, kidneys) - Bastard Strangles!

*****Bacteraemia with abscess formation in other organs (eg: liver, kidneys) - Bastard Strangles!

** Streptococcus equi subsp. zooepidemicus

****Streptococcus equi subsp. zooepidemicus

**Can infect the respiratory tract (nasal cavity, paranasal sinuses, trachea and bronchi/bronchioles)

*****Can infect the respiratory tract (nasal cavity, paranasal sinuses, trachea and bronchi/bronchioles)

**URT infection can be indistinguishable clinically from Strangles, but does not cause suppurative lymphadenitis (cf: S.equi subsp. equi)

**URT infection can be indistinguishable clinically from Strangles, but does not cause suppurative lymphadenitis (cf: S.equi subsp. equi)

**Fungal infections  

**Fungal infections