Quaglio - Specific Case Studies and Practical Examples

Question 1

What is scoliosis in fish, and what causes it?

Answer 1

Scoliosis is a lateral curvature of the spine.

Caused by Vitamin C deficiency, trauma, or genetic abnormalities.

Question 2

How does Vitamin C deficiency affect fish?

Answer 2

Leads to skeletal deformities like scoliosis and lordosis.
* Impairs collagen synthesis and wound healing.

Vitamin C is essential for maintaining healthy connective tissues in fish.

Question 3

What is Gas Bubble Disease (GBD), and how is it diagnosed?

Answer 3

Caused by supersaturation of gases in water.
* Diagnosed through clinical signs like exophthalmos, abnormal swimming, and visible gas emboli.

GBD can be fatal if not addressed promptly.

Question 4

What are the histological findings in Gas Bubble Disease?

Answer 4

Presence of gas emboli in blood vessels and tissues.
* Evidence of tissue necrosis and hemorrhages.

Question 5

How does UV radiation affect fish health?

Answer 5

Causes sunburn and epidermal necrosis, particularly in shallow or clear water.
* Leads to increased susceptibility to secondary infections.

Question 6

What are common clinical signs of bacterial septicemia in fish?

Answer 6

Hemorrhages in fins, gills, and skin.
* Swollen abdomen and exophthalmos.
* Lethargy and reduced feeding.

Question 7

What is the significance of ‘white spot’ lesions in fish?

Answer 7

Indicate Ichthyophthirius multifiliis infection (‘Ich’).
* Visible cysts on skin and gills, accompanied by respiratory distress.

Question 8

How is ‘Ich’ diagnosed and treated?

Answer 8

Diagnosed through observation of white cysts and wet mount microscopy.
* Treated with formalin or salt baths and improved water quality.

Question 9

What are granulomas, and what do they signify?

Answer 9

Granulomas are nodular inflammatory lesions caused by chronic infections (e.g., Nocardia, Mycobacterium).
* Indicate a prolonged immune response.

Question 10

What are the key diagnostic findings in Nocardiosis?

Answer 10

Granulomas in internal organs like liver, spleen, and kidneys.
* Branching Gram-positive rods visible on histopathology.

Question 11

How are swim bladder infections diagnosed in fish?

Answer 11

Observed through abnormal buoyancy and swollen abdomen.
* Necropsy reveals thickened swim bladder walls and presence of nematodes (e.g., Anguillicola crassus).

Question 12

What are the impacts of Diplostomum spp. (eye flukes) on fish?

Answer 12

Cause cataracts and blindness.
* Affected fish are more vulnerable to predation and have reduced feeding efficiency.

Question 13

What is Proliferative Kidney Disease (PKD), and its causative agent?

Answer 13

A kidney disease caused by Tetracapsuloides bryosalmonae (a myxozoan parasite).
* Leads to kidney swelling, anemia, and lethargy.

Question 14

How is PKD diagnosed?

Answer 14

Histopathology showing kidney hypertrophy and infiltration of inflammatory cells.
* Detection of spores or PCR confirmation of the parasite.

Question 15

What are the clinical signs of Viral Nervous Necrosis (VNN)?

Answer 15

Erratic swimming and loss of equilibrium.
* Skin discoloration and exophthalmos.
* High mortality, especially in juvenile marine fish.

Question 16

What is Epizootic Ulcerative Syndrome (EUS), and how does it present?

Answer 16

A fungal disease caused by Aphanomyces invadans.
* Presents with deep, ulcerative lesions and muscle necrosis.

Question 17

What are the common water quality issues leading to disease outbreaks?

Answer 17

Low dissolved oxygen.
* High ammonia or nitrate levels.
* pH imbalances and turbidity.

Question 18

How are fish affected by overcrowding in aquaculture?

Answer 18

Increased stress and aggression.
* Poor water quality and higher risk of disease outbreaks.
* Reduced growth and feeding efficiency.

Question 19

What are the histological findings in Flavobacterium infections?

Answer 19

Necrotic lesions in skin and gills.
* Gill hyperplasia and erosion in Columnaris disease.
* Hemorrhages and tail rot in Cold-water disease.

Question 20

What is the role of environmental assessment in fish pathology?

Answer 20

Identifies stressors such as poor water quality, pollution, and temperature fluctuations.
* Helps prevent disease outbreaks by addressing underlying causes.

Question 21

How is fish necropsy performed to identify internal pathologies?

Answer 21

External inspection for lesions and deformities.
* Ventral incision to examine internal organs.
* Organ-specific observations (liver, spleen, kidneys).

Question 22

What are the signs of bacterial swim bladder infections in eels?

Answer 22

Loss of buoyancy control.
* Hemorrhages and thickened swim bladder walls.
* Presence of Anguillicola crassus nematodes.

Question 23

How do fungal infections like Saprolegnia manifest in fish?

Answer 23

Cotton-like growths on skin, fins, or gills.
* Secondary infections and lethargy.
* Commonly caused by poor water quality or injuries.

Question 24

What are the key findings in Epizootic Hematopoietic Necrosis Virus (EHNV)?

Answer 24

Severe necrosis in spleen and kidneys.
* Basophilic inclusion bodies on histopathology.
* High mortality in rainbow trout and redfin perch.

Question 25

What are the effects of suboptimal nutrition on fish health?

Answer 25

Reduced growth and immune function.
* Higher susceptibility to infections.
* Deficiencies leading to deformities or organ dysfunction.

Question 26

How are case studies used in fish pathology education?

Answer 26

Provide real-world examples of disease outbreaks.
* Illustrate diagnostic and treatment methods.
* Help apply theoretical knowledge to practical situations.

Question 27

What are ‘white cysts’ in muscle tissue indicative of?

Answer 27

Larval cestode infections (e.g., Triaenophorus crassus).
* Causes reduced marketability and economic losses.

Question 28

What is the importance of differential diagnosis in fish pathology?

Answer 28

Distinguishes between diseases with similar clinical signs.
* Ensures accurate treatment and management.

Question 29

What are the benefits of integrated disease management in aquaculture?

Answer 29

Combines environmental, nutritional, and biosecurity strategies.
* Reduces disease incidence and enhances fish health.

Question 30

What lessons can be learned from specific case studies in fish pathology?

Answer 30

Importance of proactive water quality monitoring.
* Role of early detection and rapid response in controlling outbreaks.
* Impact of nutrition and biosecurity on fish health.