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Created page with "Also known as: '''''Ascorbic Acid Deficiency — Hypovitaminosis C''''' ==Introduction== Most animals can synthesis vitamin C in sufficient quantities for normal growth and func..."
Also known as: '''''Ascorbic Acid Deficiency — Hypovitaminosis C'''''

==Introduction==
Most animals can synthesis vitamin C in sufficient quantities for normal growth and function, but '''many fish cannot''', as they lack the enzyme L-gulonolactone oxidase for synthesis of vitamin C from glucose.

Vitamin C is a cofactor for hydroxylation of proline to hydroxyproline, an '''essential component of collagen''', and thus it is necessary for the formation of '''connective tissues, scar tissue in wound repair and bone matrix'''.

Vitamin C also facilitates the '''absorption of iron'''. It can spare vitamin E in '''reducing peroxidation of lipids''' in fish tissues, and is essential for the regeneration of vitamin E after oxidation.

It is necessary for a '''maximum rate of immune responses''' and enables a good response to stressors.

Fish show signs if they are fed diets deficient in vitamin C. Most commercial feed ingredients are almonst completed devoid of vitamin C and it has to be supplemented. However vitamin C is very '''sensitive to oxidative destruction''' during processing and storage and that a significant amount is lost at that time.

==Clinical Signs==
The most common signs observed with vitamin C deficiency are '''skeletal deformities''' seen as: '''spinal lordosis and scoliosis''', stress fractures and opercular and gill lamellar deformation.

This may appear to the owner as a slight asymmetry at the level of the spine.

Fish may otherwise be normal, or may show '''external and internal haemorrhaging''', usually preceded by anorexia and lethargy.

Wound healing may also progress at a reduced rate.

==Diagnosis==
'''Radiography''' is useful in identifying any spinal deformities, however these may have arisen through trauma or inheritance.

Reliable '''measures of vitamin C''' deficiency include:
:Low '''liver and kidney''' concentrations
:'''Vertebral collagen level''', especially in channel catfish and rainbow trout

==Treatment==
Treatment involves '''vitamin C supplementation'''.

Care should be taken to take into account the oxidation that can occur during feed processing and storage.

More '''stable derivatives''' of vitamin C have been developed to counteract these problems by conjugating ascorbic acid with '''phosphate or sulfate'''.

Fish are more prone to developing bacterial infections, and any problems should be dealt with promptly.

{{Learning
|flashcards = [[Ornamental Fish Q&A 23]]
}}

==References==
National Research Council,Committee on the Nutrient Requirements of Fish and Shrimp (2011) '''Nutrient Requirements of Fish and Shrimp''' ''National Academic Press''

Lovell, T. (1998) '''Nutrition and Feeding of Fish''' ''Springer''

Roberts, R. (2001) '''Fish Pathology''' ''Elsevier Health Sciences''

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