Parasitology Flashcards

Question

Which malaria is the worst and why?

Answer 1

Falciparum (constant high fevers that barely come down)

Answer 2

combination of plasma membrane and thin, translucent, secreted envelope IN FLAGELLETE

Answer 3

infertility abortion up to 5 motnhs after breeding

Answer 4

The “artificial insemination” industry prescribes for bovine trichomonosis a rigorous protocol of six weekly T. foetus negative cultures for bulls older than 365 day of age. GOLD STANDARD

Answer 5

Cryptosporidiosis caused by Cryptosporidium spp. feacal oral diarrheoa NO TREATMENT

Answer 6

Trichinellosis (trichinosis) caused by Trichinella spp. through meat (worms) reproduce in body and babies go into muscles Pigs intermediate host

Answer 7

Oxidase Catalase O/F (Oxidative/fermentation

Answer 8

Acetoin CAMP Carb fermentation Clumping Enteropluri lactose fermentation motility Oxi/ferm sorbitol sucrose urea trehalose

Answer 9

Quarantiine

Answer 10

a parasite that depends on a host for nourishment, repro, habitat and survival. Can't survive away from host.

Answer 11

An organsim that gets its nourishment from dead or decaying organisms Fungi

Answer 12

Flea, tick, louse, blood fluke, takeworm etc.

Answer 13

– Opportunistic mycoses – Dermatophytes – Systemic mycoses – Mycotoxicoses

Answer 14

saprophytes mucosal commensals Chronic lesions (reponse resembles that to foreign bodies)

Answer 15

Opportunistic mycoses Ubiquitous saprophytic moulds Cause respitory disease Outbreaks occur when large numbers of conidia are inhaled or penerate eggs

Answer 16

conidial nd hyphal adhesions triggery proinflammatory cytokines (cell wall) exoenzymes catalase siderophores melanin (free radical scavenger) Caseating tubercle-like lesion in which hyphae may be seen Horses - topical tratment (antifungal) Clean environment, sanitise and ventiation (all animals) Cause encephilitis in eggs

Answer 17

Yeast – Spherical cells single bud attached by a slender stalk – Surrounded by a polysaccharide capsule – Grow rapidly (2-4 days) on blood agar or Sabouraud agar – Creamy white colonies variably mucoid – Worldwide distribution – Serotypes A – C. neoformans var grubii – Serotypes B & C – C. neoformans var gattii – Serotype D – C. neoformans var neoformans – Ecological niche * Grows well in bird poo – C. neoformans var. gattii = Certain eucalyptus species provide saprophytic niches – Tropism for nervous tissue – Virulence – Capsule * Inhibits phagocytes * Activates the alternative complement pathway * Suppresses leucocyte migration * Depresses antibody synthesis – No evidence of transmission between animals – Environmental exogenous infection – Inhalation * Nasal, sinuses and brain – Direct entry via wounds – Granulomatous lesions – Disease usually occurs in animals with cell mediated immunity deficit (except C. neoformans var. gattii) – Young – AIDS patients – FIV in cats – Koalas ?? * Housing in niches * Koala susceptibility – C. neoformans var. gattii virulence – Diagnosis – Latex cryptococcoal agglutination test (LCAT) * Detects the presence of capsular antigen in serum or CSF * Crypto-LA test

Answer 18

Fungi associated with the skin - Microsporum * M. canis → carnivores (cats and dogs) * M. gypseum → horses - Trichophyton * T. equinum → horses * T. verrucosum → cattle

Answer 19

Geophilic – Inhabit the soil – Infections of animals due to prolonged exposure of contaminated soil – Sporadic – Not easily spread from animal to animal (not very contagious) – Hair in soil enhances infectivity – Infections promoted by wet conditions and biting insects Zoophilic – Specialised skin parasites of animals – Some easily infect species other than preferred host – Young animal in close contact ✓ * Contagious – High humidity and temperature✓ – Skin trauma and poor nutrition ✓ – Concurrent disease ✓ Anthropophilic – Specialised skin parasites of humans – Survive briefly in soil – May infect animal

Answer 20

– Entry via skin abrasion – Conidia (asexual spores) can survive for long periods in moist environments – Up to 3 years in some species – Hyphae invade walls of hair follicle. – Hyphal tip penetrates the hair cortex both by pressure and by hydrolysing the keratin – Secondary bacterial infection of follicles – Antigens are highly allergenic and induce a delayed hypersensitivity reaction

Answer 21

– Microscopy examination of skin scrapings – Culture – Sabouraud agar – Dermatophyte Test Medium

Answer 22

– UV light can have some curative effect (sunlight) – Some may be self-limiting – Clipping hair – Topical treatment – Iodine – Imidazoles (inhibit ergosterol synthesis) – Antisepetic rinses and antifungal shampoos – Prolonged treatment necessary – Does not stop spread – Does prevent re-infection – DISINFECT THE ENVIRONMENT !!! – Bleach, Iodine and most common disinfectant – Inanimate objects (fomites), bedding and rugs etc.. – Drying and exposure to sunlight !!! – **Isolation if zoophilic !!

Answer 23

– Zoophilic – Natural host is the cat – Ringworm in cats and dogs – Can infect many species including humans – Zoonosis – Carriers in cats and dogs – ~ 50% will fluoresce under Wood’s lamp – Colony appearance – Fluffy, white to yellow flat colony with radiating edges – The reverse surface exhibits a lemony to chromic yellow pigment – Microscopic features – Spindle shaped thick walled macroconidia

Answer 24

– Geophilic – Natural soil saprophyte – Infects a wide range of animals and man – Lesions highly inflammatory – Colony appearance – Powdery cinnamon surface – The reverse surface may or may not be pigmented – Microscopic features – Thin walled symmetrical spindle shape macroconidia

Answer 25

– Zoophilic – Horses – Very rarely in humans – Young horses most susceptible – < 4 years old – Most cases occur particularly in humid weather during autumn and winter – Affected animals must be isolated – Contaminated harness and grooming gears disinfected – Bleach (0.5% sodium hypochlorite) – Colony appearance – White, cottony with a yellow edge – Reverse is yellow to red-brown – Microscopic features – Macroconidia rare – Microconidia spherical to pyriform (pear-shape)

Answer 26

– Zoophilic – Cattle – Can infect humans – Can survive for many years in farm buildings – May grow on semi-dried faecal material – Calves most susceptible - Lesions around the face and eyes – Most cases occur in the winter – Groups of animal affected – Contagious – Usually, self-limiting – Topical treatment – Colony appearance – Deeply folded, white to brilliant yellow – Grow slowly requires thiamine and inositol – Microscopic features – Macroconidia rare – Microconidia ovoid to pyriform (pear-shape)

Answer 27

– Mycotoxins – Low molecular weight, non-antigenic substance , many are heat-stable – Formed on feeds following growth of fungi under favourable temperature and moisture – Exposure by ingestion (mostly) – Toxins are secondary metabolites – Formed during the stationary phase of culture – Growth may occur on crops or in poorly stored feed – Pigs, dairy and feedlot cattle – Optimum conditions for toxin production vary between species – Varying host susceptibility with age – Disease manifestation – Acute disease with overt signs – Chronic with reduced growth rate or reproductive efficiency – Increase susceptibility to other disease – Diagnosis can be difficult – Absence of specific signs in chronic disease – Uneven distribution of toxin in feed – Instability of some toxins and lack of detection methods – Fusarium graminearum – Aspergillus flavus – Perennial rye grass staggers – Claviceps spp. – Pithomyces chartarum

Answer 28

- produce extremely toxic aflatoxins, the most toxic being aflatoxin B1 – A. flavus is ubiquitous and can grow and produce toxin on most solid foodstuffs – Considerable variation in species susceptibility to toxin – Humans cause of food poisoning – Outbreaks occur particularly in warm moist conditions – The toxins inhibit RNA and protein synthesis and cause hepatic centrilobular necrosis and fatty infiltration – Acute disease may cause sudden death, or there may be less acute forms with haemorrhage, jaundice and anorexia – Chronic disease may cause reduced feed conversion and enhanced susceptibility to concurrent disease. – Intoxication of sows may cause abortion with few other signs – Aflatoxins are highly carcinogenic – Control and prevention – Minimise storage time (time from harvesting to feeding) – Monitor feed – Ammonia gas to detoxify contaminated feed – Dilute infested feed to reduce concentration (no longer acceptable in EU)

Answer 29

– Feed and tissue – Thin-layer chromatograpy * Examined under UV * B1 and B2 is blue – High performance liquid chromatography – Immunoassay – Biological assay * Ducklings * Chicken embryos * Shrimp larvae * Trout embryos

Answer 30

* loss of food source * dessication * increase in tonicity (salts) * change in O2 concentration * change in pH * temperature change * or terminal stage of a life cycle (ie. oocyst coccidia)

Answer 31

neonatal porcine coccidiosis * pale, watery diarrhoea * decreased growth * 5-15 day old piglets * high morbidity & low mortality

Answer 32

Abortion in cows * no clinical signs in cows that abort * mostly in the second trimester of pregnancy * autolysis but no gross pathological lesions * seropositive congenitally infected heifers have a 7.4 times increased risk of abortion in their first pregnancy

Answer 33

Brain cyst Epidemiology * domestic and wild cats main transmitters * oocysts in cat faeces most likely source (children) * raw or undercooked meat (adults) * causes abortion in sheep death in kangaroos Multiple births in cattle

Answer 34

roundworms

Answer 35

Feacal oral injection

Answer 36

HOT *Haemonchus (“Barber’s pole”) *Ostertagia (“small brown stomach worm”) *Trichostrongylus (“black scour worm”)

Answer 37

Ill thrift- poor condition, lethargy Scouring- poor condition, fly strike Anaemia- pale mm, bottle jaw, lethargy Basically DAD: Diarrhoea, Anaemia & Death

Answer 38

* Age (young and lactating most susceptible) * Nutrition (protein enhances immunity) * Stress * PPR (around birth and lactation) * Resistance due to the immune response (IR) * Resilience – the ability to produce under parasitism

Answer 39

prey intermediate host exploite predator prey relationship

Answer 40

grass and soil

Answer 41

1. Associated with water 2. Indirect life cycles – snails as IH; 3. Many have wide host range (F.hepatica) 4. Most persist for years in the host so... 5. Cause chronic disease

Answer 42

Liver fluke

Answer 43

* Signs are weakness, pale mucous membranes due to anaemia (blood loss) and often jaundice (yellowing) * Drenching (TCBz) * Non-chemical control (pipe water and keep dams/creeks fenced) * Vaccination (exptn) * Selective breeding (n’yet) * Biological control (of IH?)

Answer 44

From rabbit to dog when dog eats rabbit Rabbit gets it from faecal eggs shead on ground

Parasitology Flashcards

(71 cards)