fish diseases due to improper of feed deficiency

1. Harapriya

2. Introduction
 Nutritional diseases, defined by Snieszko (1972) as ‘the
deficiency, excess, or improper balance of the
components present in a fish’s diet’,
 An imbalanced diet consists of either an excess or
inadequate intake of any dietary component.

3.  An imbalanced diet consists of either an excess or
inadequate intake of any dietary component.
 Nutritional imbalance can be caused by an inability of
the body to absorb certain nutrients or result from a
poor diet. Depending on the nutrients in short or excess
supply, imbalances create unpleasant side effects and
conditions that could lead to serious disease

4. Major dietary components
1. Protein
2. Carbohydrates
3. Lipids
4. Vitamins
5. Minerals

5. 1. Proteins
 Fishes have a high dietary requirement for protein
both as a source of amino acids for protein synthesis,
for maintenance, growth, reproduction and repletion
of depleted tissues and also for gluconeogenesis and
metabolic energy.
 Protein is the most expensive component of fish diets.
 The essential amino acids for all species of fish are
“TAMIL TV HPL”

6.  Protein and AA deficiencies have long been recognized to impair
immune function and increase the susceptibility of animals to
infectious diseases, as protein malnutrition reduces the
concentration of most plasma AA, and these have an important role
in the immune response.
 Non-specific defence mechanisms were negatively affected by
protein-deficiency as it reduces lysozyme activity.
 The sole precursor of NO is arginine, this (NO) produced by fish
macrophages plays an important role in macrophage killing of
microorganisms
Cont,

7. Major AA deficiency
Lysine Dorsal fin erosion,( fig -1.1)
Leucine,
tryptophan
Lysine, arginine
histidine
Spinal deformities (fig-1.2)
methionine and
tryptophan
Lenticular cataract (fig-1.3)
Histidine Catract

8. Fig-1.1
Fig 1.2
Fig 1.3

9. 2. Carbohydrate
 Natural fish food usually does not include high dietary carbohydrate levels,
particularly in carnivorous fishes.
 Fish efficiently utilise dietary carbohydrates for energy (Lovell 1999).
 Excessive dietary carbohydrate levels can result in hepatocyte degeneration and
excessive glycogen deposition in salmonids and ornamental cyprinids.
 Dietary carbohydrate may affect fish disease and stress tolerance.
 Example, in atlantic salmon, varying dietary carbohydrate level affects immunity
and resistance to bacterial infections to a minor extent (waagbo, glette, sandnes &
hemre 1994).

10.  Dietary fibre can trap pathogenic bacteria and prevent their access to
gut mucosa (Trichet 2010). Feeding high fibre diets to rainbow trout
increased feed consumption, gastric evacuation time and decreased
ADC (Hilton, Atkinson & Slinger 1982)
 Dietary chitin stimulates the innate immune response by increasing
complement activity, cytotoxic activity, respiratory burst and phagocyte
activity.
 Chitin in fish diets interferes with bacteriolytic activity of lysozyme in
trout stomach (Lindsay 1984).
 Thus, chitin may be used as immunostimulant (Esteban et al. 2001).
Cont,

11. 3.Lipids
 Lipids are the main conventional energy sources in fish diets
 dietary lipid level spares protein.
 Fish appear capable of synthesising fatty acids of the ω-7 and
ω-9 series but not the ω-6 (linoleic) or ω-3 (linolenic) series.
 Dietary lipids are also a source of essential fatty acids (EFA).
Fish, as other vertebrates, have dietary requirements of n-3 and
n-6 polyunsaturated fatty acids (PUFA) but specific EFA
requirements are different in marine and freshwater species
(Sargent et al. 2002). Two signs of EFA deficiency in fish are
poor growth and feed efficiency (Sargent, Henderson & Tocher
1989);

12.  EFA are precursors of eicosanoids, a group of highly biologically active compounds
that comprise prostaglandins, prostacyclins and thromboxanes, which are hormone-
like compounds produced by the cells and that have a wide range of physiological
functions, including immune and inflammatory responses (sargent et al. 2002; wall,
ross, fitzgerald & Stanton 2010).
 Fish fed diets including lipids showed higher white blood cell count and leucocyte
respiratory burst than fish fed a lipid-free diet.
 This enhancement of immune response in lipid supplemented diets was mainly
because of the efa.
 Essential fatty acid deficiency the clinical features are invariably associated with hepatic
swelling due to severe lipid infiltration.
 There is consistent anaemia, associated with failure of the liver to secrete haemopoietin,
and mortality is high.
Cont,

13.  Hepatic lipidosisis a common problem seen in captive
fishes and can occur for multiple reasons. Examples
include starvation, a high percentage of carbohydrates in
the diet, a high amount of lipids, and rancidity.
 Lipoid liver degeneration-Auto oxidation is important
not only in that it reduces the availability of the fatty acids
to the host; oxidative rancidity but also induces high levels
of free radicals, peroxide aldehydes and ketones, all toxic
to fish, and also capable of reacting with other dietary
components.
Cont,

14.  Fish those are suffering from lipoid liver disease
show anaemia (manifested pale gills and
fragility of erythrocyte), a bronzed, rounded
heart, and a swollen liver with rounded edges.
 Histologically,
1. Extreme infiltration of hepatocytes by lipid
which causes loss of cytoplasmic staining and
distortion of hepatic muralia.
2. Degeneration of splenic and renal
haemopoietic tissue with high levels of pale-
staining pigment in MMC.
3. Auxiliary haemopoiesis in the subepicardial
tissues and the periportal areas takes place.
It is an important case in Rainbow trout farming, in
case of the severe anaemia and hepatic ceridosis it
is difficult to satisfactory recovery.
The are bronzed, rounded and swollen liver
and heart
and very pale gills
Ceroid infiltration of hepatic cells

15.  Tissue and membrane antioxidant (e.g. tocopherol and
vitamin C) are reduced when feeds containing
oxidising lipid are fed.
 This results in biomembrane changes, mainly
alterations in membrane permeability and fragility.
 Rancid lipids are toxic per se: they also react with
protein to lower its biological value and have a
deleterious effect on other vitamins, notably vitamins
A and C.
Cont,

16. Vitamin
 Vitamins are complex organic substances, usually of
low molecular weight, which are essential to a wide
variety of metabolic processes.
 They are only required in trace amounts in the diet
but requirements may increase during growth and
spawning, or in high-energy feeds.

17.  A part of water-soluble vitamins may be derived from
gut microbiota in warm-water fish although in
carnivorous coldwater fish, gut microbiota is not
asignificant source of vitamins. So it is need to be
supplemented from exogenous sources through feed.
 Oversupplementation of vitamins C and E, improved
stress tolerance, immunological response and disease
resistance in fish (Koshio 2007; Lim et al. 2008a)

18.  Both vitamins have antioxidant properties, besides other
distinct metabolic functions and have been shown to affect
complement and antibody production, and macrophage
function, including respiratory burst and intracellular killing.
 Vitamin C deficiency is immunosuppressive, and fish fed
vitamin c-deficient diets are more prone to infectious diseases
than fish fed vitamin c-sufficient diets (lim, shoemaker &
klesius 2001a).
 Vitamin A (which also has antioxidant properties) effect on the
immune system and disease resistance.

19. Vitamin A
essential
1. Normal vision,
2. Embryonic development,
3. Maintaining mucous
membranes,
4. Cellular membrane
permeability,
5. Bone development and
6. Corticosterone synthesis.
Hypovitaminosis A
1. Poor growth,
2. Keratomalacia,
3. Blindness,
4. Exophthalmia,
5. Haemorrhages at the
base of the fins
6. Erosion of the caudal
peduncle and
foreshortening of
The gill arch and
operculum

20. cont ,,
 Vit-D calciferol is important to prevent Rickettsia and
Hypervitaminosis has been demonstrated experimentally
by feeding 3 750 000 IU cholecalciferol/kg diet in brook
trout, causing hypercalcaemia and increased haemotocrit.
 Vit –E tocopherols work with incorporating Se. mostly
important when feed contain rancid lipid it helps in
membrane permeability with muscular dystrophy and
steatitis with swim-bladder, digestive and cardiac muscle
pathology, and anaemia.

21. Fat soluble vitamin deficiency and their
syndromes

23. Degenerative myopathy of white muscle, bland and
noninflammatory, in longstanding case of pansteatitis
in a rainbow trout. The sarcoplasm is
shrunken with granular deposits within the
permysium.
Pansteatis. Severe infiltrate of
peripancreatic fat by macrophages.

25. Vit c deficiency

26. Mineral deficiency

28. Atlantic salmon from fast growing
stock on phosphorus/ascorbate deficient
diet showing deformity of the head
bones and jaw articulation.
Obstruction of the ureters with calci-
fied deposits in the nephrocalcinosis
syndrome.

29. References
 http://eprints.cmfri.org.in/
 Nutritional Diseases of Fish By Barbara D. Petty, DVM,
Ruth Francis-Floyd, DVM, MS, DACZM, Professor,
Department of Large Animal Clinical Sciences, College of
Veterinary Medicine, University of Florida
 Fish pathology by R.J Roberts
 Review Article-Nutrition and health of aquaculture fish A
Oliva-Teles1,21 Departamento de Biologia, Faculdade de Cie
ˆncias, Universidade do Porto, Porto, Portugal 2
CIMAR/CIIMAR – Centro Interdisciplinar de Investigac¸a ˜o
Marinha e Ambiental, Universidade do Porto, Porto,
Portugal

30. Thank you.. ..