Bacterial infection in respiratory
system The upper RS
airsaculitis, acute
sinusitis
– Streptococcus equi
– subsp.zooepidemicus
strangles
– Streptococcus equi subsp.equi
(vaccine)
The lower RS
bronchopneumonia -
acute
– S.equi subsp.zooepidemicus
bronchopneumonia -
chronic
S.equi subsp.zooepidemicus
Staphylococcus intermedius
E.coli,
Klebsiella spp.
Enterobacter spp.
Salmonella spp.
Rhodococcus equi
Actinobacillus equuli
Pasteurella spp.
Fusobacterium
necroforum
Bacteroides spp.
Respiratory system - Viruses
Equine Rhinopneumonia (EHV-1 and 4)
Equine viral arteritis
Equine Influenza
Equine Rhinovirus
Equine Adenovirus
Equine Rhinopneumonia
Etiologic agents- EHV-4, EHV-1
Virus Replication on mucosal surfaceof respiratory system, establishment of latency
Rhinofaryngitis, tracheobronchitis, fever
Disease of young horses(up to 2 years), older animals – mild clinicalsigns
Equine Rhinopneumonia
Incubation period 2-10 days
Frequent secondary bacterialinfection
EHV-1 biphasic fever
EHV-1 – fulminant pneumonia in transplacental infection (latepregnancy)
Equine Adenoviruses
Viruses with low virulence
Ocurrence in the age of 3 – 6 months
Mostly subclinical
Horeses are periodically reinfected
Bacterial superinfections
Equine Adenoviruses
Adenoviral pneumonia
– Immunosupression
–Failure of passive transfer of antibodies
Polysystemic disease
–SCID (severe combined immunodeficiency)
in arabian horses
Equine Influenza
Acute febrile, highly contagiousdisease
Incubation period 1-3 days
Dyspnoe, cough, fever, rhinitis, conjunctivitis
THE ALIMENTARY SYSTEM
acute enteritis
– Salmonella spp
– Actinobacillus equuli
– Clostridium perfringens type A cpb2+
chronic enteritiS
– L.intracellularis
acute peritonitis
– enterobacteria
– Bacteroides spp.
– Bacteroides fragilis
– Rhodococcus equi
– Actinobacillus equuli
THE URINARY SYSTEM
pyelonephritiS
Escherichia coli
cystitis, uretritis
E.coli, P.mirabilis
Klebsiella spp., Enterobacter
Actinobacillus equuli
Streptococcus equi subsp.zooepidemicus
Pseudomonas aeruginosa
THE REPRODUCTIVE SYSTEM
endometritiS
– E.coli, K.pneumoniae
– Pseudomonas spp.
– S.equi subsp.zooepidemicus
orchitis, epidimitis, vesiculitis
– S.equi subsp.zooepidemicus
abortions
– Salmonella spp., S.Abortus equi
Equine virus abortion
Virus is ubiqituous in the horsepopulation, animals became infectedin the first year of age
Latency in the ganglion trigeminale
abortogennic strains (various level ofendotheliotropism)
Pathogenesis
Epithelial cells Leukocytes Endothelial cells
In respiratory tract, immune system Pregnant uterus
Pathogenesis
Primary replication - epithelial cells ofrespiratory tract
Infection of endothelial cells of vesselsin nasal region, viremia associated withmonocytes and lymphocytes.
Secondary replication in endothelialcells of the uterus, CNS, testes, endocrinne organs, infection of ganglion trigeminale
Viremia
(Lymphocytes)
Infection of the
uterus ...
Latency (lymphocytes,
gangl. trigem.)
Establishment
of latency
Reactivation
Equine Viral Arteritis
Virus is ubiqitous
American isolates are more virulent
Incubation period 3 – 14 days
Subclinical course
Clinical signs: fever, leukopenia, oedemaof scrotum and abdomen, conjunctivitis, nasal and ocular discharge, abortion (10 –60%)
Pathogenesis
Initial infection of bronchial macrophagesFollowing 48 h. regional lymph-nodes,
3. day viremia
Secondary replication in the walls ofmedium and small vessels
Longlasting immunity follows naturalinfection(up to 3 years). Protectionmediate by colostral antibodies last for 2 –6 months, but interferes with vaccination.
Pathogenesis
Respiratory route – primary and most frequent way of infection, virus is shed for7 – 14 dní
Infected semen - virus id transmittedfrom persistently infected stallion to themare.
In stallions virus can persist in accessoryglands for the life . Perzistence istestosteron dependent!
EHV-1 × EVA
EHV-1
– Virus reactivation preceedes abortion formonths
– Pulmonary eodema, transudate in the thoraciccavity, petechias in myocardum of the foetus
EVA
– Abortion follows the disease of mare
– Foetus is partially autolysed
– Without specific changes
Equine exanthema coitale
Occurs in mares and stallions(vesicular and pustular changes, ulcerations)
Virus replicationon the mucosa ofgenital tract
Infection is „self-limiting“ because ofthe termosensitivity of the virus
Ulceration are often contaminated by bacterias
THE CENTRAL NERVOUS
SYSTEM
meningo-encefalitis(secondary
infection)
– S.equi subsp.zooepidemicus
– enterobacteria
Tetanus (Clostridium tetani)
EHV-1 Myeloencephalopathy
Virus strains displaying endotheliotropism
Ischemic changes due to infection of vascularendothelium (vasculitis, thrombosis, petechias in the CNS)
Dysuria, cystitis (dysfunction of motor. neurons)
Infection of mare in 2/3 pregnancy
Higher incidence during winter and spring
Paresis, ataxia of pelvic limbs
THE EYE
bacterial conjunctivitis
– S.equi subsp.zooepidemicus
– Pseudomonas aeruginosa
– Staphylococcus intermedius
– Moraxella equi
– Listeria monocytogenes
– Acinetobacter spp.
– Corynebacterium spp.
– Bacillus spp.
SEPTICEMIA
E.coli
Salmonella spp.
Actinobacillus equuli
S.equi subsp.zooepidemicus
Staphylococcus intermedius
CNS.
Equine infectious anemia
Disease of odd-toed animals
Acute febrile disease with frequentexacerbations (2-3 týdny)
Virus is replicating in monocytes andmacrophages
Virus transmission blood sucking insect
needles (vaccination)
Pathogenesis
Antigenic variations – cause of frequentexacerbations
Immunocomplexes of free virus withantibodies - glomerulonephritis,
Virus is sensitizing erythrocytes andthrombocytes to the action ofcomplement– anemia, petechias, icterus, hearth failure, oedemas
Splenomegalia
THE SKIN
folikulitis a furunculosis
Staphylococcus intermedius
lymphangitis
S.equi subsp. equi
Mycotic infection
– Microsporum canis
– Trichophyton equinum(vaccines)
Equine Papillomaviruses
Virus type Lesions Localisation
EqPV-1 Papillomas Hairy skin
EqPV-2 Papillomas Genitals
BPV-1 Sarcoids Hairy skin
BPV-2 Sarcoids Hairy skin
Equine Papillomaviruses
Typical cytopathology on the skin
Histological changes in the stratumgranulosum (inclusions)
Virus id shed by contact anddesquamation
Decontamination of the environmentis impossible
MUSCULOSKELETAL SYSTEM
Septic artritis– E.coli
– Salmonella spp.
– Actinobacillus equuli
– Pseudomonas aeruginosa
– S.equi sp.zooepidemicus
– Rhodococcus equi
– Staphylococcus intermedius
WOUNDS
Traumatic
Clostridium perfringens
type A
S.equi sp.zooepidemicus
Pseudomonas aeruginosa
Surgical wounds
enterobacteria
Actinobacillus equuli
Pseudomonas aeruginosa
S.equi
subsp.zooepidemicus
Staphylococcus aureus
S.intermedius
Top Related