DISEASES OF WATERFOWL

DISEASES OF WATERFOWL

• PARASITES– PROTOZOANS

• blood parasites

– e.g. Trypanosoma - intermediate hosts

• intestinal parasites

– e.g. Wenyonella - high host specificity

• sarcocystis (breast muscle)

– affects mostly adults

Left: Sarcocystis in mallard breast muscle

Right: Leg muscle of a black duck

– HELMINTHS

• Trematoda (flukes)

• Cestoda (tape worms)

• Nematoda (round worms)

• Acanthocephala (spiny-headed worms

– EXTERNAL

• Arthropods (louse)

– blood sucking

• Annelids (leeches)

–CONCLUSIONS: PARASITES

•Problem Only When

–At extreme concentration

–Birds are in poor body condition to begin with

–Can Be Present In Healthy Birds

»Esp. Coccidia + spiny-headed worms + feather louse

–Control Not Necessary

•BACTERIAL–AVIAN CHOLERA

•CIRCULATORY SYSTEM

•HEART LESIONS

•FECAL AND NASAL DISCHARGE SPREADS IN WATER

•PASSED TO DOMESTICS AND REVERSE

•KILLS FAST

Pinhead sized hemorrhages along fatty areas of the heart of cholera infected bird

Thickened yellowish fluid in the intestines of this cholera infected bird contains millions of bacteria that will contaminate the envrionment as the carcass decomposes or is scavenged

–BOTULISM – TYPE C

•#1 KILLER

•INGESTED IN FOOD

•MOSTLY IN DABBLERS

•ESP. PINTAILS

• “TYPE E” IN MERGANSERS IN ONE STUDY

•FLOODED AG. LAND IS PROBLEM

–CAN’T FLY

–LIMBER NECK AND CAN’T WALK

–NO EMACIATION

–MAY TRY TO USE WINGS TO SWIM

Several thousand toxic maggots can be produced by a single carcass

Waterfowl and other birds feed on the maggots as evidenced by their presence in this gizzard of a duck that died from botulism

Birds dying from botulism seem to line up in rows that represent the receding water levels as they died

Paralysis of the inner eyelid is a common sign in botulinum infected birds

Although possible, treatment of botulism is generally considered too expensive

–OTHER BACTERIAL DISEASES

•TUBERCULOSIS

•SALMONELLA

–MOSTLY DOMESTICS

–NOT A BIG PROBLEM

•VIRAL–DUCK VIRUS ENTERITIS (DVE)

•RELATIVELY RECENTLY DISCOVERED

•KILLED >40,000 IN 1973 AT LAKE ANDES IN S.D.

•ESP. IN HIGH DENSITY POP’S

•KILLS ALL AGES EQUALLY

•ESP. BLACKS, MALLARDS, TEAL

•PHOTO PHOBIA

•PROLAPSED PENIS

•NO EMACIATION

BROWN DISCHARGE FROM THE BILL, BLOOD-STAINED, OR EVEN BLOOD DRIPPING FROM THE BILL IS SEEN IN SOME DVE CASES; AND BLOOD STAINING OF THE VENT AREA (BELOW)

“COLD SORES” UNDER THE TONGUE MAY ALSO BE SEEN IN DVE INFECTED BIRDS

Lake Andes National Wildlife Refuge, South Dakota, 1973; 40,000 mallards died of DVE (duck plague)

•FUNGUS•ASPERGILLOSIS

•INHALES SPORES FROM MOLDY HAY, ETC•HITS RESPIRATORY TRACT•KILLS A FEW HERE AND THERE REGULARLY•SLOW DEATH - EMACIATION

“cheesy” fungal plaques in the lung and air sacs of a bird with aspergillosis

“bread mold” fungal mat is totally involving the air sac adjacent to the heart of this bird (left).

At right, a wood duck duckling’s lung shows the dark red “studded” or granular appearance characteristic of acute aspergillosis or “brooder pneumonia”

CONTROL AND MANAGEMENT OF WATERFOWL DISEASES

• GENERAL GUIDELINES FOR CONTROL– IDENTIFY - DIAGNOSTIC LAB

• SET PRIORITIES

– CONSIDER SPECIES

– CONSIDER MAN

– CONSIDER LIVESTOCK

• CONTROL

– SANITATION

» BURN CARCASSES

» KILL AND REMOVE SICK

» DRAIN INFECTED WATER OR FLUSH WITH FRESH

Sanitation measures may require personnel and equipment on an emergency basis

One should consider local conditions before employing the use of an all terrain vehicle to retrieve dead or dying waterfowl

Portable incinerators may be used to dispose of diseased carcasses.

Carcasses and other contaminated material should be burned, burried, or both.

CONFINE AND TREAT SICK (E.G., BOTULISM)

DISPERSE HEALTHY

MASS VACCINATION

STERILIZE WATER

PREVENT SCAVENGING

PREVENT UNNATURAL WATERFOWL CONCENTRATIONS

CONTROL CHOLERA

• SANITATION – COLLECT AND BURN

– EGGS

– NESTS

– CARCASSES

– BURN VEGETATION AND AG. LAND

– SPRAY WATER WITH CRESYLIC COMPOUND

– OTHERS AS FOR GENERAL

•MANIPULATION OF H2O

DRAIN IF POSSIBLE

AVOID OVER-WINTER IN MIGRATION AREAS

(DRAIN EACH YEAR)

BOTULISM CONTROL

• DUCK RESCUE

– NOT PRACTICAL

• SANITATION• WATER MANIPULATION

– MAINTAIN 18-24" AT DIKES

– FLUSH WITH FRESH

– DRAIN IN SOME INSTANCES

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