MPC COE Avian Diseases Clinical Signs and Gross Lesions

E. coli

Clinical signs: Anorexia/fever/lethargy, increased mortality, Respiratory signs, Swollen heads, Swollen eyes

Gross lesions: pericarditis, perihepatitis, septicemic spleen, caseous airsacculitis, omphalitis, cellulitis, and myositis in market-ready birds, septicemia, polyserositis, and granulomatous lesions in the intestine

Pasteurella multocida

Clinical signs: Acute: mortality, septicemia, cyanosis, nasal discharge, respiratory rales, bad smell; Chronic: joint, wattles, and brain swelling, subclinical

Gross lesions: Acute: consolidation of left lung, caseous air sacculitis, yolk peritonitis, sawdust liver; Chronic: suppurative/caseous localized infections, caseous exudate in wattles, comb, swollen joint

Eyrispelothrix rhusiopathiae

Clinical signs: sudden onset of depression preceding death, cyanosis, swollen red snood, occasional swollen hock joints

Gross lesions: septicemia (liver, spleen), petechial/ecchymotic hemorrhages in the muscles and heart

Salmonella pullorum

Gross lesions: Bacillary white diarrhea, gray nodules in heart, lung, sawdust liver, cecal cores

Salmonella gallinarus (fowl typhoid)

Gross lesions: swollen, bronze greenish tint to liver, drop in production, misshapen ovaries

Salmonellosis in chicks

omphalitis, caseous cecal cores, dark, swollen liver and spleen, peritonitis/polyserositis

Staphylococcus infections

Clinical signs: systemic infection, bumblefoot, omphalitis, arthritis/synovitis/OM

gangrenous dermatitis (Clostridial spp.)

Septicemia, skin necrosis, severe depression, decompose faster, areas of feather loss and sloughing, gas crepitus upon palpation

LPAI

Mild respiratory, rhinitis, tracheitis, airsacculitis, polyserositis, pneumonia

HPAI

Enlarged spleen, large and hard lung, angry brain, liver is bumpy, high mortality, cyanosis, hemorrhages, nervous signs, swollen heads, diarrhea, drop in egg production

Gross Lesions: petechial hemorrhages on the heart, pericardium, abdominal fat, proventriculus, visceral organs

Newcaslte disease

Clinical signs: high mortality, respiratory, nervous signs, diarrhea, drop in egg production

Necropsy: swollen heads, rhinitis, tracheitis, pneumonia, airsacculitis, petechial hemorrhages, diarrhea

aMPV

Clinical signs: respiratory/neurological signs, sep/tox, drop in egg production/misshapen eggs, sinusitis, excess exudate mucoid, swollen heads

Necropsy lesions: cranial bones bacterial osteomyelitis, conjuctivitis, tracheitis, pneumonia

Infectious Laryngotracheitis

Clinical: increased mortality, upper respiratory, open mouth breathing, head shaking, coughing blood, drop in egg production

Gross: severe tracheitis, tracheal plugs

Avipoxvirus

Dry: scabs on the unfeathered skin, blindness due to eye lesions, decreased feed consumption, and egg production

Wet: yellow to white, raised plaques on the mouth and larynx, gasping, tracheal plug

Infectious bronchitis

Respiratory: swollen head/airsacculitis

Renal/nephropathogenic: diarrhea, mephrosis

Reproductive: quantity and quality

Mycoplasma gallicepticum

Clear exudate like a viral infection, sinusitis, airsacculitis, polyserositis

fibrinous pericarditis, airsacculitis, perihetatitis

Mycoplasma synoviae

synovitis, joint infections, lame birds, squatters, breast blisters, swollen tendon sheaths, sticky and clear synovial exudate

Avibacterium paragallinarum/infectious coryza

Clinical signs: sharp decrease in feed and water consumption, sharp drop in egg production, swollen faces, wattles, eyes, nasal discharge

Gross lesions: catarrhal sinusitis, rhinitis, pneumonia, airsacculiltis

Bordetella avium

Clinical: sneezing, tracheal rales, open-mouth breaking, mucoid/watery nasal and ocular discharge, submandibular edema

Gross: mucoid rhinitis, sinusitis, tracheitis, collapsing of tracheal rings

Ornithobacerium rhinotracheale

looks like gelatin, pulmonary edema, hunched in, hard breathing, sinus infection, dirty feathers from snot, upper respiratory, sinusitis, tracheitis, lung consolidation with pleuritis

Aspergillosis

high mortality, pneumonia, dyspnea, air gasping, rapid breathing, nervous signs: incoordination, tremors, torticollis, paralysis, ocular lesions, granulomatous nodules, plaques in air sac, abscesses, increased mortality 3-5 days of age, open mouth breathing

Gross lesions: may see plaques if migrated to the brain, white/yellow nodules in lungs, air sacs, and brain, pneumonia, air sacculitis, encephalitis

E. acervulina

Duodenum, white to gray striations/tiger stripes

E. maxima

thickening of intestinal walls and dilation of jejunum, bloody GI contents, large oocysts, balloning of intestinal walls, pinpoint hemorrhages

E. tenella

severe typhlitis, bloody diahhrea, high morbidity and mortality, reduce gain, hemorrhage and necrosis of ceca, caseous cores, hemorrhage of ceca

Necrotic enteritis/Chlostridium perfringes

sudden death in well-freshed birds, ataxia, somnolence, depression, jejunum thin, distended, mucus colored, brown diptheritic membrane (cobblestone), foul smelling, liver spots and peritonitis

Ulcerative enteritis/Clostridium colinum

watery diarrhea, polydypsia, emaciation, sudden death in well-fleshed birds, ulcers in SI and ceca, peritonitis and intestinal adhesions, yellow focal necrotic areas in the liver

Infectious Bursal Disease

hemorrhage/inflamed bursa, low mortality, very similar to coccidiosis, diarrhea, depression, ruffled feathers, dehydration, vent picking, large, edematous/hemorrhagic bursa, intramuscular hemorrhages in the thigh/pectorals, necrosis of other immune organs

Hemorrhagic enteritis virus

Clincial signs: rapid onset bloody diarrhea and death, dead birds are pale and well-fleshed

Gross lesions: frank body in GI lumen, large spleen, mottle and friable, hemorrhages in muscles and thigh, basophilic intranuclear inclusion bodies

Poult enteritis mortality syndrome

loud vocalization/hyperactivity, depressed, anorexic, huddling, dehydration, lack of uniformity, watery and distended intestines

Runting-stunting/malabsorption syndrome

Severe weight suppression, lack of uniformity, diarrhea

Duck virus enteritis

Clinical signs: sudden death, high mortality, watery, bloody diarrhea, drop in egg production, dropping and tremors

Gross: hemorrhages and necrosis, severe hemorrhagic and ulcerative enteritis, crusty plaques in esophagus, ceca, cloaca, rectum, intranuclear inclusions

Mycobacteriumum avium ssp. avium

Clinical: progressive wasting of birds, emaciation, diarrhea

Gross: grayish yellow or white nodules in liver, spleen, SI, bone marrow, lungs and kidney

Ascaridia galli

Clinical signs: may be absent, worst in young birds to migration in small intestinal wall, mucosal damage, loss of weight, stunted growth, diarrhea, decreased egg production

Capillaria spp.

sick birds, anorexia, swallowing motions, inside of crop is dying

Histomonas meleagridis

Clinical signs: sulfur-colored diarrhea, anorexia, emaciation, debilitation, weakness, death, target lesions on the liver, cecal cores

Gross: cecal cores, liver necrosis with target lesions, peritonitis

Avian Encephalomyelitis

Clinical signs: ataxia, paralysis, fine tremors, drop in egg production

No gross lesions

Marek’s Disease

Clinical signs: transient paralysis, peripheral nerve paralysis, blindness, depression, immunosuppression, depressed, emaciated, lymphoproliferative tumors

Necropsy: visceral, cutaneous, ocular, neural form: nerve degeneration, nerve lymphocytic inflammation, swollen nerves, discoloration

Arboviruses - West Nile Virus

Drops in egg production, encephalitis, paresis, paralysis

Botulism - Clostridium botulinum exotoxin

Clinical signs: drowsiness, weakness, progressive loss of control, fine tremors, paralysis of 3rd eyelid, recumbent, death may occur shortly

Gross: no gross or microscopic lesions, crop may contain rotten ingesta or maggots

Vitamin E deficiency

Clinical signs: Encephalomalacia, ataxia, falling over, prostration on the side, exudative diathesis, muscular dystrophy

Gross lesions: swollen, red cerebellum, congested hemorrhagic or necrotic area, green-blue blood-stained gelatinous edema under skin, white to yellow degenerative muscle fibers

Vitamin B2/Riboflavin deficiency

Anorexia, paralysis, curled toes paralysis, alert but uncoordinated, demyelination and neuropathy, jerky, irregular convulsions, hypothermia, death

Lead toxicity

Stargazing, walking backwards, gizzard lining discolored, emaciation, pale, watery blood

Ionophore toxicity

drop in egg production, incoordination, leg weakness, depressed growth, myocardial enlargement, ascites, lack of mycocardial tone

Reovirus

Clinical: older birds, lameness, reluctance to walk, green discoloration of muscles and hemorrhage, stunting/poor uniformity, cull birds

Gross lesions: swelling and rupture of the hock tendons, blood-tinged fluid, edema on the hock joint, fibrinous exudate, erosion of articular cartilage, aortic rupture

Vertebral osteomyelitis/Enterococcus decorum

Clinical signs: Abnormal gait, reluctance to move, dog sitting

Gross lesions: spondylitis and osteomyelitis, swelling of T6, vertebral abscesses

Avian Leukosis Virus

B-cell tumors, absence of peripheral nerve lesions, myelocytoma, osteopetrosis (boot shanks), anemia and immunosuppression, stunting, poor uniformity, abdominal distention, hemorrhages

Rickets/Osteomalacia

Difficulty walking, soft, rubbery breaks and bones, palpable curved keel bone with cartilage tip

Gross lesions: rachitic rosary, rib fractures, widened growth plates, enlarged epiphysis

Cage layer fatigue/osteoporosis

Paralysis or fractures/deviations of spine, fractures of leg and wing bone, soft shell eggs

Tibial dyschondroplasia

Many cases subclinical

Gross lesions: cartilage plug

Perosis/chondrodystrophy

Enlarged hock, slipped tendon

Deep pectoral myopathy

edema, hemorrhage, fibrosis and green discoloration of the breast muscle

Woody breast

degeneration, necrosis, and fibrosis of the breast muscle

Thiamin deficiency

Lethargy, head tremors, stargazing, polyneuritis

Chicken infectious anemia

Clinical signs: no specific signs, anemia, SQ hemorrhages, immunosuppression, blue wing

Necropsy lesions: atrophic thymus, fatty yellowish bone marrow, bursal/splenic atrophy, hemorrhages

Inclusion Body Hepatitis

Increased mortality 3-4 days, pale, friable, swollen livers

Egg drop syndrome

Production loss due to non-packable and non-processable eggs, shell-less or thin-shelled eggs, loss of brown pigment

Mycotoxins

Decrease feed, body weight, egg production, immunity, goes off feed

Pale liver/swollen kidneys

Retriculoendotheliosis Virus

Young birds: runted birds

Turkeys >17 weeks → lymphomas

Ascites

Depressed, marked abdominal distention, reluctance to move, cyanosis, passive congestion, straw-colored fluid/jelly in body cavity, liver cirrhosis

Round heart disease

dilated cardiomyopathy

Fatty liver hemorrhagic syndrome

Clinical: increase in culls, low peak egg production, fat birds drop dead, heavy body weights

Gross lesions: heavy abdominal fat, bright yellow liver, fat droplets on liver surface, friable liver with clotted blood

Gout

Build-up of uric acid in the visceral or articular