Chitridiomycosis

Question 1

incubation period of Chitridiomycosis

Answer 1

2-10 weeks. death follows the onset of symptoms within approximately 2-3 days.

Question 2

symptoms of Chitridiomycosis

Answer 2

skin gets thickened and hardens. respiration becomes difficult because significant gas exchanged usually occurs across moist skin under normal conditions. the amphibian can become lethargic, hind legs extend, and the amphibian becomes sluggish and has no appetite. these symptoms can lead to death.

Question 3

spread of Chytridiomycosis

Answer 3

• Fungus produces spores that are releases into water
• Spores swim
• Invade skin cells of host
• Develops into thallus which produces more spores
• Can also be spread via direct contact between frogs
• Humans or other animals may spread over land

Question 4

Management of Chytridiomycosis

Answer 4

• No way of eliminating fungus from wild amphibians
• Clean and disinfect boots
• Clean and disinfect equipment
• Report any dead amphibians

Question 5

chytridiomycosis pathogen name

Answer 5

Batrachochytrium Dendrobatidis

Question 6

chytridiomycosis Life cycle specification

Answer 6

entry via skin penetration (invades outer layer of skin/epithelium)
Replication via asexual reproduction inside the thallus (zoosporangium)
Exit is via zoospores going from the thallus in the skin of an amphibian into the water.

Question 7

Chytridiomycosis Mode of transmission

Answer 7

Indirect via soil borne/water borne swimming zoospores
Direction contact via infected amphibian skin to susceptible amphibian skin.

Question 8

method of invasion

Answer 8

Infection occurs inside cells of outer skin layer that contains lots of keratin
Causes hyperplasia/hyperkeratosis
Severe thickening of skin
Grow initially in living cells but complete development in dead keratinised cells

Question 9

Impact on Host

Answer 9

Can cause suffocation, dehydration + abnormal electrolyte levels
Reddened / discoloured skin, excessive shedding, abnormal postures / behaviours, seizures
Sometimes death

Question 10

evolutionary adaptations

Answer 10

Flagella
Enables swimming through water + moist environments
Asexual reproduction

Question 11

factors affecting spread

Answer 11

Resistant species become carriers
Move fungus to new areas
Do not tolerate warm / dry conditions for more than a few hours
17ºC – 25ºC optimum
Movement of equipment + people

Question 12

Management Strategies - Prevention

Answer 12

Clean + disinfect boots or equipment from one area to the next
Report any dead amphibians