Quaglio - Specific Case Studies and Practical Examples Flashcards
What is scoliosis in fish, and what causes it?
Scoliosis is a lateral curvature of the spine.
Caused by Vitamin C deficiency, trauma, or genetic abnormalities.
How does Vitamin C deficiency affect fish?
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.
What is Gas Bubble Disease (GBD), and how is it diagnosed?
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.
What are the histological findings in Gas Bubble Disease?
Presence of gas emboli in blood vessels and tissues.
* Evidence of tissue necrosis and hemorrhages.
How does UV radiation affect fish health?
Causes sunburn and epidermal necrosis, particularly in shallow or clear water.
* Leads to increased susceptibility to secondary infections.
What are common clinical signs of bacterial septicemia in fish?
Hemorrhages in fins, gills, and skin.
* Swollen abdomen and exophthalmos.
* Lethargy and reduced feeding.
What is the significance of ‘white spot’ lesions in fish?
Indicate Ichthyophthirius multifiliis infection (‘Ich’).
* Visible cysts on skin and gills, accompanied by respiratory distress.
How is ‘Ich’ diagnosed and treated?
Diagnosed through observation of white cysts and wet mount microscopy.
* Treated with formalin or salt baths and improved water quality.
What are granulomas, and what do they signify?
Granulomas are nodular inflammatory lesions caused by chronic infections (e.g., Nocardia, Mycobacterium).
* Indicate a prolonged immune response.
What are the key diagnostic findings in Nocardiosis?
Granulomas in internal organs like liver, spleen, and kidneys.
* Branching Gram-positive rods visible on histopathology.
How are swim bladder infections diagnosed in fish?
Observed through abnormal buoyancy and swollen abdomen.
* Necropsy reveals thickened swim bladder walls and presence of nematodes (e.g., Anguillicola crassus).
What are the impacts of Diplostomum spp. (eye flukes) on fish?
Cause cataracts and blindness.
* Affected fish are more vulnerable to predation and have reduced feeding efficiency.
What is Proliferative Kidney Disease (PKD), and its causative agent?
A kidney disease caused by Tetracapsuloides bryosalmonae (a myxozoan parasite).
* Leads to kidney swelling, anemia, and lethargy.
How is PKD diagnosed?
Histopathology showing kidney hypertrophy and infiltration of inflammatory cells.
* Detection of spores or PCR confirmation of the parasite.
What are the clinical signs of Viral Nervous Necrosis (VNN)?
Erratic swimming and loss of equilibrium.
* Skin discoloration and exophthalmos.
* High mortality, especially in juvenile marine fish.
What is Epizootic Ulcerative Syndrome (EUS), and how does it present?
A fungal disease caused by Aphanomyces invadans.
* Presents with deep, ulcerative lesions and muscle necrosis.
What are the common water quality issues leading to disease outbreaks?
Low dissolved oxygen.
* High ammonia or nitrate levels.
* pH imbalances and turbidity.
How are fish affected by overcrowding in aquaculture?
Increased stress and aggression.
* Poor water quality and higher risk of disease outbreaks.
* Reduced growth and feeding efficiency.
What are the histological findings in Flavobacterium infections?
Necrotic lesions in skin and gills.
* Gill hyperplasia and erosion in Columnaris disease.
* Hemorrhages and tail rot in Cold-water disease.
What is the role of environmental assessment in fish pathology?
Identifies stressors such as poor water quality, pollution, and temperature fluctuations.
* Helps prevent disease outbreaks by addressing underlying causes.
How is fish necropsy performed to identify internal pathologies?
External inspection for lesions and deformities.
* Ventral incision to examine internal organs.
* Organ-specific observations (liver, spleen, kidneys).
What are the signs of bacterial swim bladder infections in eels?
Loss of buoyancy control.
* Hemorrhages and thickened swim bladder walls.
* Presence of Anguillicola crassus nematodes.
How do fungal infections like Saprolegnia manifest in fish?
Cotton-like growths on skin, fins, or gills.
* Secondary infections and lethargy.
* Commonly caused by poor water quality or injuries.
What are the key findings in Epizootic Hematopoietic Necrosis Virus (EHNV)?
Severe necrosis in spleen and kidneys.
* Basophilic inclusion bodies on histopathology.
* High mortality in rainbow trout and redfin perch.
