environmental and eye pathogens

Question 1

Gas bubble disease symptoms

Answer 1

● emboli in various tissues
● brain damage
● exophthalmos (wcs: eye loss)
● mortality

Question 2

High T symptoms

Answer 2

● carp: refuses food
● trout: feeds but has enteritis
● convulsive movements
● melanosis
● open opercula

Question 3

anoxia symptoms

Answer 3

● swimming on surface (piping) and bite air/gulping
● low to no feeding
● ↓motor activity
● lethargy/listlessness
● bell-up and/or rolling motion
● opercula chambers and mouth open
● gastric depletion
● no detectable lesions in tissues

Question 4

what to do with gas bubble disease

Answer 4

degassing, proper aeration

Question 5

what to do in emergency anoxia

Answer 5

potassium permanganate 3-6 ppm

Question 6

Nodular gill disease (NGD) cause

Answer 6

freshwater
protozoa amoebae on fish gills

Question 7

GBD cause

Answer 7

tot gas P water>tot gas P air (ground water source is high in gases, mainly nitrogen)

Question 8

Nodular gill disease (NGD) symptoms

Answer 8

● dyspnea
● abnormal swimming, near surface
● open opercula
● gills →pale, swollen, distal part of gill shows nodules and necrosis

Question 9

nervous necrosis disease (NND) cause

Answer 9

> 40 marine fish
betanodavirus

Question 10

nervous necrosis disease (NND) symptoms

Answer 10

● lethargy
● anorexia
● uncoordinated spiral swimming with loss of balance due to neurological problems
● change in pigmentation

Question 11

causes and diagnoses of skeletal deformities

Answer 11

causes:
● genetic→trout
● defective embryonic development
● unsuitable T
● salinity
● hypoxia
● UV
● traumatic lesions→sturgeons
● lightning
● Diet:
○ ↓Vit c→trout
○ ↑↑↑ Vit A
○ ↓ Vit K
● pathogenic or parasitic lesions
diagnosi: x-ray and histology

Question 12

whirling disease cause and prophylaxis

Answer 12

myxobolus cerebralis protozoan
salmonids fry before ossification
salmonid definitive host of indirect lifecycle (tubifex bryozoan-salmonid)
prophylaxis: concrete tand + ususal factors

Question 13

whirling disease symptoms

Answer 13

● black tail due to hypermelanosis
● neurological symptoms: whirling swimming
● skeletal deformities (due to foci of colliquation include jaw distortion, cranial deformities, shortened gill covers, lordosis,…)
high mortality in fry (90%)

Question 14

eye lesion list

Answer 14

● GBD: exophthalmus + corneal opacity
● betanodavirus: corneal opacity, keratosis
● flavobacterium: intraocular haemorrages
● lactococcus garvieae: exophthalmus
● diplostomiasis: cataracts
● scutococilliatosis: exophthalmus

Question 15

diplostomiasis cause

Answer 15

diplostomum spp. trematode. salmonid 2nd host of indirect lifecycle (snail-salmonid-d.h. bird)

Question 16

diplostomiasis sympthoms

Answer 16

cataract in lens
adult blindness
juveniles high mortality

Question 17

scutococilliatosis cause, species

Answer 17

philasterides dicentrarchii
flatfish, sparids, seahorses, sharks

Question 18

scutococilliatosis sympthoms

Answer 18

exophthalmus
ascites
haemorrages (mainly operculum)

Question 19

lactoccoccosis cause

Answer 19

lactococcus spp.
freshwater mainly, some seawater when T>19-20°C (summer)

Question 20

ph imbalances symptoms

Answer 20

acidic <6: skin, gills, eyes lesions, difficulty in breathing
alkaline >8.5: unionized ammonia toxicity, pale

Question 21

UV light lesions

Answer 21

sunburn in shallow not turbid water fish, dorsal part of the body

Question 22

ammonia toxicity symptoms

Answer 22

● swimming on surface (piping) and bite air/gulping
● low to no feeding
● ↓motor activity
● lethargy/listlessness
● purple-blueis gills