animal pathogens Flashcards
-bovine tuberculosis (bacteria)
-trypanosomiasis (parasite)
-ringworm (fungi)
-rinderpest (virus)
symptoms of bovine TB
-chronic disease takes years to develop
-lymph nodes are infected first then tubercles (round lesions) appear on the surface of the chest cavity of lungs.
killing of mycobacteria in TB and immune evasion
-what inate cell used
need activated macrophages to kill mycobacteria
-mycobacteria secrete protein and lipid factors to block phagosome maturation
long term evasion of mycobacteria
-lesions begin to form undetected
-an accumulation of macrophages leads to lesion formation.
-continues until death of cow. (similar to human TB)
spread of TB
-resevoirs and transmission animals
-no country has managed to eradicate TB without tackling wildlife resevoirs
-potential reveoirs = deer, fox, rodents
but badgers are strongly implicated in transmission to cows
how is african animal trypanosomiasis spread and symptoms
by tsetse fly
-swelling, fever, reduced milk. weight loss
the trypanosomes responsible for disease
-trypanosoma congolense
-trypanosoma vivax
-trypanosoma brucei spp. (Tb. gambiense and Tb. rhodesiene)
-most common
-can spread independent of tsetse fly (needles..)
-only causes disease in animals (can casue sleeping sickness in humans)
trypanosoma immune evasion
-VSG
go through antigenic vairation with
VSG (variance surface glycoprotein) switching.
this always them to induce an immune response then change their antigen coat so immune systum does not recognise them
what is ringworm,
-what fungus is it
when are the infetions the worst
-how is it transmitted
-trichophyton verrucosum
-fungal infection of hair
-outbreaks in autumn/ winter due to animals confined indoors
-zoonotic infection through direct contact/ bites
what is rinderpest
-what virus
-effects on agriculture
-type of virus
-consequence of immune cells
morbillovirus
acute, highly contagious viral disease of cattle, water buffalo and other wildlife.
-in 1889, cattle from india introduced the virus into africa and 90% of african cattle were destroyed. led to mass starvation
-morbillovirus
-reduced B cells
what is foot and mouth disease?
-what animals does it occur in
-virus of greatest economic threat
-what type of virus is it
occurs in hoofed animals e.g. pigs, cows, sheep ect
-retrovirus- non- enveloped positive ssRNS virus
diagnosis of foot and mouth disease
-control
-vaccination
-vaccination challenges
-virus detectbale 2 days prior to clinical manifestations. environmental shedding is the very contagious stage.
-control= slaughter infected animals and uninfested contacts.
vaccine= available but immunity is short lived.
animals (infected or vaccinated) can develop carrier status. and virus therefore remains in lymph nodes.
challenges= seven serotypes with high muation rate therefore hard to produce vaccine against all strains
why are wildlife cats in danger of extinction?
through infections of domestic cats infecting wildcats
2 viruses found in feline cats
-feline leukaemia virus
-feline immunodefiency virus
-how do they impact immune systum
-what type of virus is it?
-how glycoproteins change
both surpress immune system
-retovirus with a RNA genome
-reverse transcriptase
feline immunodefiency virus is the cat equivalent of HIV.
-how does it impact cats
-how is it spread
-infects T helper cells
-impairs immune systum
spread by bites/ scratches
feline leukaemia virus
-what was it first thought to be
-how is virus transmitted
-treatment/ control
-first thought to be cancer. however viral particles were discovered.
-virus can be horizontally transmitted
-variety of vaccines are available but none 1005 work
avian influenza
bird flu diseases
-1997 influenza A H5N1
-2013 H7N9
-what kind of virus it it?
-H5N1 transmitted to humans. 60% mortality rate
-H7N9 is less deadly but more difficult to track
-orthomyxovirus
different subtypes based on
-haemagglutinin (H)
-neuraminidase (N)
-18 different H antigens (recognise/ bind to host)
-11 different N antigens (release of new viral particles)
what are avian influenza A viruses classified into:
1) low pathogenicity avian influenza A virus
2) highly pathogenic avian infleunza A virus
what birds does avian influenza virus appear
-appears naturally amoung birds.
wild migratory birds are natural carriers of virus but are resistent to severe infection from virus
tranmission of pathogen trichomonas in birds occur and prevention
spread via unwashed bird feeders through contamination and sharing of feeding stations.
prevention- allow feeders to dry out as trichomonas cant survive periods outside
symptoms of eimeria spp. in goats and poultry
-what kind of disease is it
-how can it be treated
severe bloody diarrhea and intestinal damage
-coccidiosis disease
-vaccination treatment, chemotherapy.
