Infectious diseases of horse - Blog Universitas...

Infectious diseases of

horse

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


THE URINARY SYSTEM

pyelonephritiS

Escherichia coli

cystitis, uretritis

E.coli, P.mirabilis

Klebsiella spp., Enterobacter


Streptococcus equi subsp.zooepidemicus

Pseudomonas aeruginosa

THE REPRODUCTIVE SYSTEM

endometritiS

– E.coli, K.pneumoniae

– Pseudomonas spp.


orchitis, epidimitis, vesiculitis


abortions

– Salmonella spp., S.Abortus equi

Urogenital system - Viruses

EHV-1

EHV-3

Equine viral arteritis

Equine infectious anemia

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)


– enterobacteria

Tetanus (Clostridium tetani)

CNS infection - Viruses

EHV-1 Myeloencefalopathy

Rabies

Bornas disease

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


– Pseudomonas aeruginosa

– Staphylococcus intermedius

– Moraxella equi

– Listeria monocytogenes

– Acinetobacter spp.

– Corynebacterium spp.

– Bacillus spp.

SEPTICEMIA

E.coli

Salmonella spp.


S.equi subsp.zooepidemicus


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


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.


– Pseudomonas aeruginosa

– S.equi sp.zooepidemicus

– Rhodococcus equi

– Staphylococcus intermedius

WOUNDS

Traumatic

Clostridium perfringens

type A

S.equi sp.zooepidemicus


Surgical wounds

enterobacteria



S.equi

subsp.zooepidemicus

Staphylococcus aureus

S.intermedius

Nosocomial infection in

veterinary hospital

multirezistant strains

–Actinobacillus equuli

–Staphylococcus inetrmedius

–S. aureus (MRSA)

S. equi supsp. zooepidemicus

Infectious diseases of horse - Blog Universitas...

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