Non-infectious Disease of Fish

1. NO NAME ID.NO
1 MEGERSA AKASA 004292
2 MESFIN KASAHUN 004293
3 MESKEREM TOLLERA 004294
4 MULETA OLANI 004296
5 REMEDAN TEMAM 11088373
6 MOHAMMED AHMED 11088370
7 MOHAMMED JEMAL 11088371
SCHOOL OF VETERINARY MEDICINE
DEPARTMENT OF VETERINARY MEDICINE
FISHERIES AND FISH DISEASES
GROUP ASSIGNMENT : Group : 5,DVM 5TH YEAR
Title : Nutritional Disorders Of Fish
SUBMISSION DATE : 14/12/2013 E.C
SUBMITTED TO : Dr.WAKTOLA TADESE

2. Nutritional Disorders Of Fish

3. Introduction
 Formulation of well balanced diets and their adequate feeding are two of
the most important requirements for successful aquaculture.
 Nutritional status is one of the most important factor that determine the
ability of fish to resist diseases.
 Nutritional diseases of fish may develop as a result of :
 Deficiency (undernutrition),
 Excess (overnutrition), or
 Imbalance (malnutrition) of nutrients present in their food.
 An imbalanced diet consists of either an excess or inadequate 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. Cont…
 The deficiency and imbalance diseases :
 Deficiency disease are two types–deficiency or imbalance of the macro
nutrient in the diets-the protein; carbohydrate;lipid.
 And deficiency of the micronutrient-vitamins and minerals
 In terms of macronutrient usually lipid component of the macronutrient
that the most serious problem arises in terms of practical diets–deficiency;
oxidation;imbalance.
 The disease usually develops gradually because animals have body reserves
that make up for nutritional deficiency up to a certain extent. Disease signs
develop only when supply of any diet component falls below critical level.
 When there is too much food, the excess that is converted to fat and
deposited in fish tissues and organs, may severely affect physiological
functions of the fish.

5. Major dietary components
 Protein
 Carbohydrates
 Lipids
 Vitamins
 Minerals

6. Proteins
 Fish diet must be contain high level of high quality protein since protein is
one of the most expensive component of the diet.
 Fishes have a high dietary requirement :
 Protein as a source of amino acids for protein synthesis,
 For maintenance, growth, reproduction & repletion of depleted tissues,
 Glycolysis, gluconeogenesis & metabolic energy.
 Ensures the formation and activity of essential enzymes and hormones.
 The essential amino acids for all species of fish are “TAMIL TV HPL”.
 The principle feature determining protein quality for fish nutrition in
the level and avability of the essential amino acid.
 Deficiency of one or more of these leads to deficiency diseases.

7. Cont…
 The most common signs of protein and/or amino acid deficiency in fish
are:
 Reduction of growth rate
 Mortality
 Scoliosis and Lordosis
 Anemia (Reduction of RBCs 750000/m3).

8. Toxic amino acids
• Nutritional pathologies may arise from the consumption of feed proteins
containing toxic amino-acids or their derivatives.
• Feed proteins containing toxic amino-acids which have been reported to
have a negative effect on fish growth and feed efficiency (including
eventual fish death) include the plant legumes Leucaena
leucocephala(toxic non-protein aminoacid–mimosine).
• In addition to the non essential amino-acids, certain EAA (ie. leucine) have
also been reported to exert a toxic effect in fish when present in dietary
excesses.
• For example, the reported toxicity signs for a dietary excess of
leucine(13.4% of diet) in rainbow trout (O. mykiss) included scoliosis,
deformed opercula, scale deformities, scale loss, and spongiosis of
epidermal cells.

9. Major Amino acid Deficiency
Amino acid Deficiency symptom
Lysine Dorsal /Caudal fin erosion ;
Increased mortality
Leucine ,
Tryptophan
Lysine,Arginine
Histidine
Spinal deformities
Methionine and Tryptophan Lenticular cataract
Histidine
Methionine
Tryptophan
Cataract
Increased mortality
Scoliosis,lordosis, cataract; caudal fin
erosion ; decreased carcass lipid

10. Histamine Poisoning
 Tuna, Mackerel and other dark-fleshed fish have a short life span.
 Formation of histamine complex due to :
 Bacterial decarboxylation of histidine has been found in the flesh of
marine fish species.
 This toxicity can also occur in non-scombroid fishes, anchovies, herrings or
pilchards where it is mostly common in pinnipeds.
 Clinical signs are :
 lethargy, anorexia and throat inflammation.
 Treatment :
 Antihistamines can provide temporary relief and the animal start ingesting
feed within 2-3 days.
 Epinephrine is effective in severe or acute cases of histamine reaction.
 Cortisone and diphenhydramine hydrochloride can also be effective.

11. Carbohydrate
• Natural fish food usually does not include high dietary carbohydrate levels,
particularly in carnivorous fishes.
• Fish efficiently utilise dietary carbohydrates for energy.
• Excessive dietary carbohydrate levels can result in hepatocyte
degeneration & excessive glycogen deposition in salmonids & ornamental
cyprinids. For instance salmonids may store high level of glycogen in the
liver and also exhibit symptoms of diabetes when fed too much CHO.
• Dietary carbohydrate may affect fish disease & stress tolerance.
• Dietary chitin stimulates the innate immune response by increasing
complement activity, cytotoxic activity, respiratory burst & phagocyte
activity.

12. Sekoke diseases
 Sekoke disease is one of the common diseases related to Carbohydrate.
 It is also called Spontaneous Diabetes in carp which are fed with
extremely high-starch diets. So, elimination of the excess amount of starch
from the diets can prevent this disease.
 Sekoke diseases in carp has been described in japan in association with
the incorporation of significant levels of silk worm pupae in the diet.
 Lipid infiltration of parenchymatous organs, bilateral cataract and
degenerative changes in extrinsic eye muscle, retina.

13. Lipids deficiency
 Pathological conditions occur in fish from excess dietary fats, deficiency
of fatty acids and the toxic effect of unsaturated dietary fats.
 Reduced growth of the fish.
 Skin de-pigmentation.
 Fins erosion.
 Rapid swimming is followed by immobility and loss of reflex.
 Fish may float or sink to the bottom and then recover or die.
 Ascetics.

14. Essential fatty acid deficiency signs in fish
Fish species Deficiency sign
Oncorhynchus mykiss Increased mortality;increased susceptibility to
caudal fin erosion; decreased haemoglobin and
RBC; shock syndrome; swollen pale liver;
reduced spawning efficiency
Oncorhynchus kisutch swollen pale liver; increased hepatosomatic
index (fatty liver); high mortality
Cyprinus carpio Increased mortality; fatty liver
Lates calcarifer Reduced growth and feed efficiency, reddening
of fins
Ctenopharyngodonidella Reduced growth and feed efficiency, swollen
pale liver, increased mortality, lordosis, shock
syndrome

15. EFA Deficiency
 Marine fish larvae require essential fatty acids (EFA) for :
 normal growth and development.
 Fatty acids are essential components of biomembranes and precursors of
some physiological modulators such as the eicosanoids.
 Marine fish in general, unlike their freshwater counterpart, cannot
effectively elongate and desaturate saturated fats to unsaturated ones and
so require the presence of unsaturated fatty acids in their diets.
 Essential fatty acids such as :
 Docosahexaenoic acid [DHA, 22:5(n-3)] and,
 Eicosapentaenoic acid [EPA, 20:5(n-3)].
 Are commonly found in live food such as microalgae (e.g.,
Nannochloropsis), copepods, rotifers and Artemia.

16. Cont…
 Deficiency in these fatty acids is associated with larval mortality known as
“shock syndrome” in which the larvae display unusual sensitivity to stress.
 Any handling or disturbance (e.g., sorting, transfer, strong aeration) of
grouper larvae with this condition invariably results in mortality.
 This disease has been reported in Epinephelus malabaricus in Thailand
and in E. tauvina and E. fuscoguttatus in Singapore.
 Body weakness and mortality is observed after 21 day of starting feeding
for E. malabaricus.
 This disease is not transmitted to other healthy individuals by affected
fish.

17. Cont…
 Causative agent:
 This condition is associated with low levels of essential fatty acids in live food.
 Stages affected:
 Day 21 larvae for E. malabaricus, stage 1 (about day 12) and stage 2 (day 23) for E. tauvina and
E. fuscoguttatus are affected.
 Gross clinical signs:
 General body weakness and mortality is observed starting day 21 for E. malabaricus. High
mortality occurs in stages 2 and 3 for E. tauvina and E. fuscoguttatus.
 Effects on host:
 Total mortality is observed after day 30 for E. malabaricus.
 Transmission:
 The disease is not transmitted to other healthy individuals by affected fish.
 Diagnosis:
 Visual observation of larval behavior (weak movement) is confirmed by fatty acid analysis of
live food.

18. Cont…
 Preventive and control methods:
 Feed 15 day-old larvae with brine shrimps enriched with fish oil at 25-50
ml/m3 of rearing water. While it is important to maintain a clean
environment by sediment removal and water management.
 Avoid unnecessary mechanical stress to the larvae by tender handling,
using mild aeration and employing flow-through system of water
management.
 The condition can be alleviated by enrichment of rotifers with n-3 HUFA
or Nannochloropsis (syn. Chlorella). Bring the EFA levels of the live food to
around 12% by enrichment.
 Supplementation with DHA is reported to slow down mortality in grouper
while supplementation with EPA was less effective in other marine
species.

19. Fatty liver
 Symptom :
• Fish fed regularly on high fat feed
with no essential fatty acids (such
as trash fish) will easily suffer
from toxic reaction caused by
peroxidation of unsaturated fat.
Appetite is poor and growth is
slow. It may also lead to bone
defect or anaemia.
 Treatment :
• Improve feed quality fish, store
fish feed properly and use suitable
additíves.

20. Nutritional Myopathy
Accompanying Ceroidosis
 Lipid peroxidation can occur both in solution and in the cell because
unsaturated fats are highly susceptible to oxidants. When peroxidation
occurs in the cell membrane, cellular integrity is compromised that could
lead to certain myopathies.
 Causative agent:
 This disease is associated with diets containing rancid fat or
polyunsaturated fatty acids and low contents of vitamin E.
 Stages affected:
 Cromileptes altivelis fingerlings and broodstock are affected by this
disease.

21. Gross clinical signs:
Affected fish show emaciation, darkening of body color (Fig-a), petechia at
the base of the operculum (Fig-b) and occasional deformity of the spinal cord.
Fig. Nutritional myopathy in Cromileptes altivelis: a) Darkening of body color and
spinal deformity and b) petechia at the base of the operculum

22. Cont…
 Effects on host:
 The disease can cause low but continuous mortality in C. altivelis
fingerlings.
 It can also cause mass mortality in C. altivelis broodstock.
 Transmission:
 The disease is not caused by an infectious agent; it is non-transmissible.
 Diagnosis:
 Histopathologically, myofibril degeneration including extensive myolysis
and macrophage invasion in degenerated fibers are observed in the
skeletal muscles (Fig-a).
 Ceroid deposits, a kind of lipo-pigment which stains pink with PAS
reaction in the hepatocytes, is typical (Fig-b).

23. Fig. Nutritional myopathy in Cromileptes altivelis: a) Macrophage invasion, H & E
stain and b) ceroid deposits (pink in PAS reaction)

24. Cont…
 Preventive and control methods:
 Proper food management can prevent this disease.
 To prevent rancidity of polyunsaturated fatty acids, food should be kept in
freezers under –30°C and consumed as soon as possible.
 Antioxidants such as vitamin E are effective against this disease since they
prevent peroxidative damage to cells.
 Enrichment of food with vitamin complex can stamp out mass mortality.

25. Vitamins
• 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.
• Vitamins are of two groups : the fat soluble and water soluble vitamins.
• Fat soluble vitamins are complex organic substances found in
different forms.
• The water soluble vitamins are coenzymes 01" many essential enzymes
catalyzing carbohydrate metabolism.
• The fatty soluble vitamins can be stored within the body and metabolized
only slowly, so that cumulative hypervitaminoses resulting from relatively
massive intakes are possible, they are namely vitamins A,D ,E and K.

26. Cont…
• 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 a significant source of vitamins. So it is need to be supplemented from
exogenous sources through feed.
• Over supplementation of vitamins C & E, improved stress tolerance,
immunological response & disease resistance in fish.
• Both vitamins have antioxidant properties, besides other distinct
metabolic functions & have been shown to affect complement & antibody
production, and morphology function, including respiratory burst and
intracellular killing.

27. Avitaminosis
 Absence of a particular vitamin leads to serious metabolic disorders
referred to as Avitaminosis that is frequently fatal.
 Some of the vitamin deficiency signs can lead to :
 Poor appetite, poor feed efficiency and reduced weight gain.
 Non-specific growth retardation and susceptibility to diseases.
 The farmers may obtain indirect clues of vitamin deficiency from this sign.
 Vitamin deficiency disease does not usually occur in ponds which can
result in depressed immune function and chronic disease.
 Optimum level of vitamin is required for the development of immunity in
the early stages of their life cycle.

28. Vitamin Deficiency Signs
 Thiamine : Anorexia, poor appetite, muscle atrophy, loss of equilibrium, poor growth, congestion of fins and
skin, fading of body color, lethargy.
 Riboflavin: Eye and skin hemorrhage, photophobia, pigmentation of iris, striated constrictions of abdominal
wall, dark coloration, appetite, anemia, poor growth, in skin and fins.
 Pyridoxine: Nervous disorders, hyper-irritability, anemia, loss of appetite, rapid rigor mortis, peritoneal
edema cavity, colorless serous fluid, rapid breathing, exophthalmia.
 Pantothenic acid : Clubbed gills, necrosis, cellular atrophy of gills, gill exudate, loss of appetite, lethargy,
poor growth, skin hemorrhage, skin lesions and deformities.
 Niacin : Poor growth, anorexia, lethargy and mortality.
 Inositol : Distended stomach, increased gastric emptying time, skin lesions, de-pigmentation and poor
growth.
 Biotin : Loss of appetite, lesions in colon, altered coloration, muscle atrophy, spastic convulsions and
fragmentation of erythrocytes, skin lesions and poor growth.
 Folic acid : Lethargy, fragility of caudal fin, dark coloration, macrocytic anemia, poor growth.
 Choline : Poor food conversion, hemorrhagic kidney and intestine, poor growth, accumulation of neutral fat
in hepatopancreas, enlarged liver.

29.  Ascorbic acid : Skeletal deformities, poor wound healing.
 Nicotinic acid : Loss of appetite, lesions in colon, jerky motion, weakness, edema, muscle
spasms while resting, sensitivity to sunlight, poor growth, skin hemorrhage,
lethargy and anemia.
 Vitamin B : Poor appetite, low hemoglobin, fragmentation of erythrocytes, macrocytic anemia,
reduced growth.
 Vitamin C : Impaired collagen formation, eye lesions, anorexia, hemorrhagic skin, liver, kidney
and muscle, reduced growth, dark coloration, loss of balance, fin necrosis, high
mortality.
 Vitamin A : Ascites, ceroid in liver, spleen and kidney, anemia, fragility of red blood cells, poor
growth, exophthalmia, kidney hemorrhages, depigmentation and soft exoskeleton.
 Vitamin D : Poor feed utilization, raised blood counts, slow growth rate, decreased ash levels,
calcium and phosphorous, poor growth, soft exoskeleton, lethargy.
 Vitamin E : Muscular dystrophy, pathological condition in reproductive organs, increased
permeability of capillaries, hemorrhages and edema in various parts of the body.
 Vitamin K : Anemia, prolonged coagulation time.

30. Broken Back Syndrome/Scoliosis
• Broken Back Syndrome is a well-known channel catfish disease in super-
intensive culture system.
• This disease arises if fish are fed vitamin C deficient diets for more than
eight weeks.
• Vitamin deficiency leads to biochemical dysfunctions and consequent
organ dysfunction.
• Other morphological and functional changes have been also reported in
fish deprived of vitamin C.

31. Cont…
Causes :
 Trauma
 Tryptophan deficiency
 Vitamin C deficiency
 Ascorbic acid
 Organophosphates like :
 Fenthion
 Trichlorfon
 Malathion

32. Cont…
 Treatment
 Quarantine all fishes that may be infected; this will prevent a possible
spread of infection.
 kept in a medicated tank or aquarium.
 Keep your fishes on a nutritionally balanced
diet.
 Fishes with dietary imbalances should be given vitamins.

33. Blindness-Melanism Syndrome
 The disease was firstly described as a :
 “Loss of Scales Syndrome” by Raymond in indigenous fishes of the West
Indies, especially Ocyurus chrysurus and Lutjanus analis.
 Caused by : vitamins deficiency.
 Fish show :
 A loss of appetite, melanism, weight loss, lesion,& muscle degeneration.
 Some of them can hardly catch the pellets which also suggest blindness.
 Ulcerative skin lesion is often seen on the head, latero-dorsal body part,
and fins.
 Ocular lesions such as keratitis and aphaky are sometimes detected.

34. Mineral Deficiency
 Fish can also minerals absorbed from water
 Minerals required only small quantities
 In fish, minerals provide important roles in :
 Osmoregulation,scale and skeleton formation and
 Intermediary metabolism.
 Some trace elements are required as coenzyme and for vital maintenance for
cellular function in the immune system.
 Difficult to study the mineral requirements of fish are because some minerals are
required very minute amounts.
 Some other minerals are absorbed from water in significant quantities through the
gills as well as from the diet.
 Mineral deficiencies appear due to :
 Dietary imbalances and interaction of dietary components.
 Some of mineral deficiency signs :
 Skeletal deformities, reduced resistance to diseases and anemia.

35. Cont…
 Zinc, copper, iron and selenium are required at trace amount for metalo-
enzymes which are vital to maintain cellular functions in the immune
system.
 Very little is known about the effects of trace elements on immune
function of finfish species.
 Iron is very important nutrient for fish as well as for microorganisms also,
even the ability of pathogens to enter to a host depends on the availability
of iron.
 Microcytic Anemia is one of the deficiency signs of iron which can be
occurred in several fish species.
 Iron deficiency makes the host fish more susceptible to infectious agents.

36. Minerals Functions Deficiency symptoms
Calcium and Phosphorous Bone formation, blood
clotting, supply high
energy phosphorus
compounds.
Slow growth rate and
increased mortalities,
scoliosis, lordosis and skull
deformities.
Magnesium Act as Enzyme cofactor,
involved in the Loss of
appetite, poor fat
metabolism.
Lordosis, poor growth and
protein growth, tetany.
Iron Essential constituent of
haeme, Cytochromes and
peroxidases.
Microcytic Homochronic
anemia.
Manganese Bone formation, arginase
cofactor and involved in
erythrocyte regeneration.
Sluggish movement, loss of
equilibrium, poor appetite,
weight loss and mortality.
Iodine Regulate total oxygen use. Thyroid, Hyperplasia (goiter).
Table : Major minerals, their functions and deficiency symptoms in fish and shellfish.

37. Minerals Functions Deficiency symptom
Copper A constituent of oxygen carrying
pigments in blood.
Reduce weight gain, feed efficiency,
and copper level in body.
Reduce growth, cataracts.
Increase in intestinal cell
proliferation and apoptosis.
Gill function and resistance against
parasite & bacteria establishment are
compromised.
Potassium Maintenance of cellular volume
& membrane potentials & the
generation of nerve impulses.
Reduce growth & feed efficiency.
Aorexia, convulsions,tetany & death.
Selenium Maintenance of fish health, in
particular fish immunity.
Depresses growth, reduce feed
intake and weight gain.
Low guthathione peroxidase activity,
impaired reproduction, anemia,
exudative diathesis, muscular
dystrophy & increased mortality.
Zinc Involved in various metabolic
pathways such as protein
synthesis, growth,immunity &
energy metabolism.
Bilateral, central or sublenticular
cataract development, poor growth,
darkening colour, erosion of fins &
skin, dwarfism & poor egg
hatchability.

38. Hyponatremia
 Hyponatremia is a disease of marine fish which is related to salt
deficiency.
 It is most common in freshwater pinnipeds, saltwater animals, otarids,
phocid seals, and other marine mammals.
 Clinical signs are :
 Periodic weakness, tremor, lethargy, incoordination, and anorexia.
 Severely affected animals may collapse in an Addisonian crisis, which can
be fatal.
 Sodium chloride infusion therapy can provide effective protection.
 Animals should be provided with continuous freshwater flow.

39. Starvation
 Starvation can occur due to number of reasons other than obvious under
feeding:
 Incorrect assessment of the weight of receiving the food.
 Presentation of a feed of inappropriate physical characteristics, usually
when size of individual particle is too large for size of fish or sinks too
quickly through the water.
 Signs of starvation are easy to spot and include :
 loss of condition, loss of weight and failure to reproduce.
 These may be an increase in cannibalism, ranging from fin nipping to
attempts to swallow whole fish particularly very young ones.

40. Conclusion
 Fish health management has become one of the basic requirements for
sustainable aquaculture development. But, most of the farmer involved in
aquaculture practice do not have sufficient knowledge on aquaculture
health management practices. So, it is very essential to focus the efforts
on disease prevalence and fish pathogens.
 Deficiency symptoms are seen to be interwoven and nutritional disorder
in any cultured organism may not be limited to just a particular deficiency
or non inclusion of certain feed components. It is therefore advisable
culturist and feed manufacturers to include adequate amount of essential
nutrients in feed at an times irrespective of the animal's stage of growth.

41. Diagnosis of nutritional deficiency:
 Presumptive diagnosis of nutritional deficiency is
based on clinical signs and combined with evidence
of an inadequate diet.
 Definitive diagnosis requires identification of a
specific nutritional deficiency in diet.

42. Treatment and control
 Treatment of disease due to nutritional imbalance depends on:
 Provision of fish with right kind of food with sufficient quantity according to
diagnosis of the types of deficiency of nutritive components.
 Mathematical formulation of a complete ration must be followed by ration
preparation, analysis and actual feeding of fish to be assured that all nutrients are
available.
 Physical preparation of the ration must also be considered to allow for
presentation of the nutritionally balanced diet to the fish in such away that it can
be ingested and digested. Taste or palatability of the ration for each fish species
must be considered. Fish have a highly sensitive sense of taste,so the ration must
pass the palatability test. When presented to the fishes in order for it to be
completely and continuously ingested.
 The ration must be fed to the fish at prescribed time intervals because of a more
or less limited stomach capacity.
 The amount of ration fed to confined fish daily to maintain nutritional depends on
f ish species ,fish size,ration quality, water temperature and type of ration.

43. Prevention and control
measures
 Aquaculture Health management means the management approaches to prevent
and control the outbreak of emerging and reemerging diseases which begins with
prevention of disease.
 Proper management of water quality and nutrition is the first step in fish
disease Prevention. It is impossible to prevent diseases outbreaks without this.
Poor water quality, nutrition or immune system are associated with stress which
allows the pathogens to cause a disease.
 Nutritional diseases are not contagious and rarely happen but cannot be cured
by medications. Best way to prevent and control through provision of good
water quality and good management.
 Timely observation of fish behavior and feeding helps in primary detection of
disease. It provides easy diagnosis odd disease before the majority of the
population becomes sick.
 A balanced diet can provide high nutrients to recover from deficiency diseases
and high yields. Diets may also have negative effects inducing nutrient
deficiencies, toxin production or induction of pathogens into the fish.

44. “PREVENTION IS BETTER THAN CURE.”
“Keys will open the gates of the
heaven "
" The same keys will open the gates
of the hell."

45. References
• Shoaibe Hossain Talukder Shefat1* and Md. Abdul Karim2, Nutritional
Diseases of Fish in Aquaculture and Their Management: A Review.
• Edgar C. Amar and Celia R. Lavilla-Pitogo,Chapter5.NutritionalDiseases.
• Shailesh Saurabh, and K N Mohanta, Nutritional disorders of Fishes with A
Special Reference to Ornamental Fish : An Overview.
• Dr. Sarvendra Kumar,Nutritional pathology of fish.
• Good aquaculture practices series 4,Prevention and Treatment Of Fish
Diseases.