EXTERNAL SYMPTOMS FOR DIAGNOSING POULTRY DISEASES

BODY
*Symptom*	*Possible Cause*
Emaciation...	Off-feed; nutritional deficiencies; lymphoid leukosis; enteritis; gizzard impaction; tuberculosis; unknown
Stunted, uneven growth....	Gizzard impaction; bluecomb disease; alfatoxin poisoning; synovitis; contaminated hatching egg
Swellings...	Ruptured air sac; edema
Twitching, muscular spasm...	Botulism; infectious bursal disease
Trembling...	Epidemic tremors; encephalitis (brain damage)
Paralysis...	Botulism; Marek's disease; arthritis; aflatoxin poisoning; epidemic tremor
Dehydration...	Acute lack of water; coccidiosis; infectious bursal disease; nutritional imbalance-dietary salts
Nervousness...	Hysteria; drug intoxication; Newcastle; fungus infection
Lying on breast, legs paralyzed...	Algae poisoning; acute lack of water; yellow jasmine poisoning; botulism; drug toxicity

FEATHERS
*Symptom*	*Possible Cause*
Moist under wing...	Infectious coryza
Loss of...	Molting
Deposits at base of shafts...	Lice or mite eggs
Soiled hackle feathers...	Infectious coryza, eye infection
Feathers picked...	Lice; nutritional deficiency-methionine; birds not debeaked
Depigmented...	Nutritional deficiencies-lysine, iron or folic acid
Broken on upper thigh...	Self picking
Feather eating...	Nutritional deficiency-methionine

Skin
*Symptom*	*Possible Cause*
Pigmentation excessive ...	Poor production; high pigment intake
Nodules, mainly legs...	Marek's disease
Nodules over vent...	Flukes (rare)
Moist, necrotic, edematous...	Necrotic dermatitis, exudative diathesis
Darkened, purplish...	Erysipelas; fowl cholera
Crusted areas...	Erysipelas; scab; gangrenous dermatitis
Scabby hip...	Self picking, inflicted by other birds
Gangrenous, green...	Hemmorhage; arthritis; gangrenous dermatitis
Vent irritated...	Northern fowl mite; lice (occasionally)
Pale...	Anemia; nutritional deficiencies-iron, copper, or vitamin B₁₂

Head
*Symptom*	*Possible Cause*
Swollen, puffy...	Ruptured air sac; infectious coryza; injury; Newcastle disease

Comb
*Symptom*	*Possible Cause*
Mottled, red and white margins...	Frozen
Eruptions, nodules...	Fowl pox
White, scaly, powdery...	Favus

Eyes
*Symptom*	*Possible Cause*
Watery...	Infectious coryza
Blindness...	Fowl pox; aspergillosis; Arizona paracolon; paratyphoid
Watery, red, inflamed, closed...	Laryngotracheitis; ammonia burn; Newcastle disease; nutritional deficiency-vitamin A
Cataracts...	Epidemic tremor
Crusts on eye lids...	Nutritional deficiency-vitamin A; fowl pox
Pupil irregular, blindness...	Marek's disease
Blood in eye...	Hemorrhagic anemia
Large, swollen...	Mycoplasma infection

Face
*Symptom*	*Possible Cause*
Swollen...	Infectious coryza; Newcastle disease; nutritional deficiency-vitamin A; E. coli
Darkened, purplish...	Erysipelas; fowl cholera; septicemia; injury
Nodules...	Fowl pox

Nostrils
*Symptom*	*Possible Cause*
Discharge...	Infectious coryza; chronic respiratory disease; infectious bronchitis; influenza

Mouth
*Symptom*	*Possible Cause*
Pustules...	Nutritional deficiency-vitamin A
Crusts at margins...	Nutritional deficiencies-pantothenic acid or biotin
Beak soft, rubbery...	Nutritional deficiencies-vitamin D or calcium-phosphorus imbalances
White coat over tongue and in mouth...	Wet form of fowl pox
Ulcers...	Mycotoxins; chemical injury

Wattles
*Symptom*	*Possible Cause*
Swollen, bulbous...	Infectious coryza; fowl cholera
Nodules...	Fowl pox

Neck
*Symptom*	*Possible Cause*
Paralysis (limber neck)...	Botulism; yellow jasmine poisoning
Twisting...	Newcastle disease; fowl cholera; brain infection; improper injection of Marek's vaccine
Retracted over back...	Newcastle disease; nutritional deficiency-thiamin
Retracted under breast...	Nutritional deficency-vitamin E; Newcastle disease
Scabby necrotic areas...	Improper injection of drugs; other injury

Legs
*Symptom*	*Possible Cause*
Paralysis...	Marek's disease; botulism; heat stoke; epidemic tremor; cage layer fatigue; vitamin E deficiency; algae poisoning; yellow jasmine poisoning; acute lack of water
Rough, scaly...	Fowl pox; scaly leg mite
Bowed, weak...	Nutritional deficiency-vitamin D; osteodystrophy
Bone bends...	Nutritional deficiency-vitamin D
Joint swelling...	Infectious synovitis; paratyphoid; pullorum; zinc deficiency; staphylococcosis; tenosynovitis; arthritis
Tendon at hock displaced...	Perosis (nutritional deficiency-manganese or choline)
Stilted gait...	Tenosynovitis
Shank depigmented...	Nutritional deficiency-vitamin A; coccidiosis; any low grade slow disease (for any length of time)
Toes twisted...	Genetic

Feet
*Symptom*	*Possible Cause*
Joints fixed...	Tenosynovitis
Swollen foot pad...	Infectious synovitis; bumblefoot
Toes curled...	Nutritional deficiency-riboflavin; genetic; management deficiency
Foot pad cracked, dermatitis...	Nutritional deficiency-biotin or pantothenic acid; management deficiency
Bird walks on toes...	Tenosynovitis
Toes twisted...	Genetic

Droppings
*Symptom*	*Possible Cause*
Profuse...	Enteritis; excess roughage in diet
Bloody...	Cecal coccidiosis; Newcastle disease
Green...	Feed intake low; bile not diluted
Sulfur yellow...	Blackhead
Light yellow or yellowish-green...	Fowl typhoid; fowl cholera
Foamy...	Intestinal parasites (protozoa)

Egg Production
*Symptom*	*Possible Cause*
Sudden severe drop ...	Newcastle disease; infectious bronchitis; laryngotracheitis; influenza-A, mycotoxin, mismanagement (no lights, feed, or water)
Unsatisfactory...	Infectious coryza; fowl cholera; chronic respiratory diseases; diet deficiencies; gizzard impaction; fowl pox; hepatitis; lice; mites; ascarids; capillaria; lymphoid leukosis; coccidiosis; enteritis; pullorum; fowl typhoid; aflatoxicosis; adenovirus infection; toxins
Egg wrinkled, depigmented...	Necrotic enteritis; infectious bronchitis
Production pause...	Epidemic tremor
Poor shell quality...	Newcastle disease; infectious bronchitis; adenovirus infection; diet deficiency; T-2 fusariotoxin

Death
*Symptom*	*Possible Cause*
Instant, few or no prior signs...	Aortic rupture; acute lack of water; fowl cholera; overheated, fatty liver hemorrhagic syndrome
High mortality-producing diseases...	Fowl cholera; erysipelas; exotic Newcastle disease; acute coccidiosis; aflatoxin; botulism; poison; fatty liver hemorrhagic syndrome

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Last modified: Thursday, 15-January-1998.
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