Poultry disease

Progressive wasting of adult birds with occasional diarrhea, can die suddenly without signs

Lesions - emaciated bird, atrophy of the breast muscle, no internal body fat

avian mycobacteriosis - mycobacterium avium - avian TB

Avian mycobacteriosis - diagnosis

gross lesions and histopath

• characteristic granulomatous inflammation with acid fast rods in center of lesion

Avian mycobacteriosis - prevention

All-in all out breeder programs to eliminate infected birds

separate young and old birds

cull affected birds

granulomas develop in intestinal tract, rupture to release bacteria into intestinal lumen and into feces

avian TB, avian mycobacteriosis

Chicks 1-2 weeks old, dullness followed by ataxia- rest on hocks and reluctant to move

Fine tremors of head and neck when handled

Chicks incapable of moving - die from trampling, dehydration and starvation

Avian encephalomyelitis

No visible gross lesions, pale foci in gizzard muscle

recovered birds ocassionally develop cataracts

Avian encephalomyelitis

Avian encephalomyelitis -prevention

vaccination - prevents egg production drops and protect progeny through maternal antibody

Appear when chick 1-2 weeks old

raised fibrinous plaques or “diptheric” nodules on mucus membranes of mouth, esophagus or upper part of trachea - mouth lesions make eating and drinking difficulty, tracheal lesions occlude glottis (tracheal plugs)

nodules increasing in size forming large brown to yellow scabs that dry off and drop off on wattle, comb, eyelids, un-feathered areas

Fowl pox - wet form and dry form

Presumptive diagnosis - scabs on skin, comb, wattles or other unfeathered areas, or yellow plaques on mucous membranes of mouth or esophagus, diptheric membranes

definitive diagnosis

fowl pox

histopath of scabs

viral isolation of chorioallantoic membrane of embryonated eggs (dropped CAM method) - intracytoplasmic inclunsions

Fowl pox prevention

vaccination - live vaccine

vaccinate birds in patagium, thigh stick used in turkeys

Reduction of cannabilism, and flying insects reduces transmission

Sneezing snicking, gasping, and moist rales, young chicks depressed and huddle under a heat source

depressed dehydrated and ruffled feathers

water diarrhea with excess urates

decline in egg production in addition to resp signs

Thin-shelled wrinkled irregulary shaped eggs

Infectious bronchitis bronchitis - coronavirus

Three resp diseases that look similar in the field

infectious bronchitis (coronavirus) newcastle disease, infectious laryngotracheitis (herpes virus)

Infectious bronchitis virus - prevention

strict isolation on the farm - all in all out - cleaning and disinfection of the poultry house

nasal discharge, moist rales, coughing, gasping, extended neck, swollen red eyes, blood stained mucus, 5-70% mortalitiy, most chicks recover in 2 weeks

blood and caseous.fibrinous plugs in the trachea

Infectious laryngotracheitis - herpesvirus

infectious laryngotracheitis diagnosis

histopathology of trachea or viral isolation (intranuclear inclusion bodies of tracheal epithelium)

infectious bronchitis - diagnosis

ELISA of IB antibody titers (tentative)

Viral isolation - in embryonated eggs

PCR or immunofluorescence in tissue sections

Reduced egg production, reduced feed consumption, oculonasal discharge, edema of face and eyelids

cheesy exudate in infraorbital sinuses

eyelids swollen or adhered shut, facial edema/swelling

no turkeys infected

Infectious coryza - avibacterium paragallinarium

infectious coryza - epidemiology

not in turkeys

short period in environment

chronically sick birds/subclinical carrier birds main source of infection

Infectious coryza - avibacterium paragallinarium

best control - all in all out - after an outbreak depopulate to start again

can vaccinate with commercial bacterin

4 weeks of age or older - Depressed and uncoordinated followed by unilateral or bilateral paralysis of legs and wings

decreased pupil size and irregular diameter “grey eye”

Marek’s disease - herpesvirus causes lymphoma - ocular marek’s

tumors in nerves ovaries, testes viscere eye muscle and skin

Marek’s treatment

none

marek’s disease - prevention

vaccination - day 1 or three days prior to hatch

Broiler chickens - chronic respiratory disease w/ chronic sneezing, oculonasal discharge, poor feed conversion and air sac condemnations at processing

Turkey - infectious sinutsitis, swelling of one or both infraorbital sinuses, w/ nasal exudate on wings and air sac condemnations at processing

Mycoplasma gallisepticum

Mycoplasma gallisepticum - diagnosis

PCR - test of choice

Mycoplasma gallisepticum - prevention

Vaccination administered to chickens only - can kill turkeys

Voice change, swollen sinuses, dirty shoulders, submandibular swelling, conjectivitis, mucus within sinuses, tracheal collapse, raccoon eyes (exudate around eyes)

Turkey bordetellosis - Bordetella avium

Turkey bordetella - bordetella avium - prevention

all in all out, flush water lines between flocks

never backtrack from older to younger turkeys on the farm

acute death with dyspnea and mucoid discharge from the mouth, watery whitish diarrhea in some birds

vascular hyperemia of abdominal organs

Fowl cholera, pasteurella multocida

Gram negative bacteria in blood or tissues

C&S - sulfonamides, tetracyclines, pen

Liver necrosis with large granular bosophilic intracytoplasmic inclusions

Avian chlamydiosis