wildlife disease

A disease that is transmitted between wildlife and humans

Any impairement that interferes or modifies the performance of normal functions

An epidemic in wildlife

Refers to an illness or sickness

Refers to death

Refers to time

• Time & Date
• Species Affected
• Age
• Sex
• Number of Individuals Affected

Fast acting

Long lasting

• Goggles
• Coveralls
• Face mask
• Eye protection
• Rubber gloves

The person performing the necropsy (AKA pathologist)

After death

The science dealing with the nature of the disease

• To determine the cause of death
• To find out what normal looks like
• Collect info.

• Because some diseases are zoonotic
• Some diseases affect domestic animals
• Some diseases affect other wildlife species

• Prevent
• Control
• Eradicate

Science of the immune system and making vaccines to protect against fatal diseases.

Condition of being non-susceptible to a disease causing agent

humans not susceptible to certain diseases like canine parvo

A recognition system that distinguishes between self and non-self

foreign substances that elicits a specific immune response

A protein thats capable of reacting with a specific antigen

• Antibodies produced in the blood within 2-4 days
• By day 4-5 several antibodies in bloodstream & peak by day 14
• By day 30-40 almost gone from bloodstream

• Antibody production is accelerated
• Antibody synthesis is greater & more produced than the first time
• Peak level is higher and faster
• Antibodies disappear less rapidly and can remain in the blood for years

Antibodies in blood plasma and lymph fluids, act on free bacteria

Specialized cells acting on bacteria, viruses that have already been infected with host cells

• B cells- secrete antibodies
• T cells- attach cells

Intoxication from hazardous levels of lead in the body

Study of the cause of disease

• Mining waste
• Batteries
• Leaded gasoline
• Paints

• Waterfowl
• Upland birds
• Eagles
• Swans
• Loons
• Pelican
• Canada Geese

• Reluctance to fly
• Run to escape
• Wing droop
• Tendency to hide under vegatation

• Hatchette Breast
• Emaciated
• Impaction in esophagous
• Gall Bladder filled with bile

• Depth of water
• Type of underlying soil or mud
• Species attracted to site
• Last use of lead shot at site

"best guess" based on clinical signs and lesions

"based on data" final diagnosis based on pathological and toxicological findings

• Metal chelating agents
• Gastric lavage
• Endoscopy
• Surgical removal

• Invert or cultivate soil
• Dredge wetlands
• Excavate shot from shooting ranges

• Deny use of problem areas
• Rigorous pickup and disposal of dead birds

• Flesh from lead posioned birds is edible
• Lead posioning from flesh is rare
• Lead eaten can become lodged in appendix causing appendicitis

Toxic compounds produced by fungi (aspergillus flavus, aspergillus parasiticus)

• Ground nuts like peanuts
• Corn
• Other grains

• Relative humidity greater than 70%
• Temps above 70 degrees
• Moisture content greater than 14%
• Occurs in field and storage

• Humans
• Domestic animals
• Wildlife
• Birds more susceptible than mammels
• Ducks, geese and sandhill cranes

• Depression/lethargy
• Blindness
• Lack of awareness
• Inability to fly
• Tremors and wing flapping

• Enlarged swollen & pale liver
• Hemorrhages

• Do not feed grain with aflatoxin levels greater than 20ppb
• Deep plowing of grains to make unavailable
• Haze wildlife from area

• Milk
• Meat
• Grains

• Ultraviolet light used
• Green & yellow florescense test

• Excertional myopathy
• Transport myopathy
• Degenerative myopathy
• White muscle disease

A protein thats associated with muscle breakdown

Build up of fluid (aka: congestion)

• Non-infectious disease of domestic and wild animals
• Characterized by damage to skeletal and cardiac muscles

• Occurs in any vertebrate species
• Most noted in ungulates
• Long legged birds
• Raptors

Occurs in recently immobilized, captured and transported wild animals

• Vary greatly
• All ages and sexes are susceptible
• Warm environmental conditions predispose animals
• Hyperthermia
• Trouble breathing
• Weakness/muscle stiffness
• Hyperacute- very sudden death often occuring
• Acute- Dead heart muscle occurs in 2-4 days
• Subacute- kidney failure releases myoglobin
• Chronic- Die over 2-4 weeks from heart failure or paralysis

Danger & cost to animals should be weighed against scientific or management benefits

• Species
• Season & Temp
• Capture Technique

• Keep nosie down
• Cover animal evyes
• Keep animal from overheating

• Prevenitive: Antibiotics
• Balanced electrolyte solution
• Sodium bicarbonate
• Selenium preperations

Treatment: fluids to treat kidney failure and acidosis

• Fowl Cholera
• Avian Pasteurellosis

• Highly infectious disease death with 6-12 hrs
• Disease caused by bacteria: pasteurella multocida

• Bird to bird contact
• Ingestion of contaminated food or water
• Biting insects
• Ingestion most common

Most species of birds and mammels can become affected

Ability of a pathogen to cause disease

• Unreported before 1944
• Now found throughout the entire US
• Follow normal movement of birds

• Dieoffs occur anytime of the year
• Outbreaks are predictible in these areas where avian cholera is well established

• Birds lethargic & drowsy
• Approachable
• Die quickly when captured
• Convulsions
• Swim in circles
• Throw head back between wings & die
• Flight is eradic
• Mucous discharge from mouth

• Visceral & subcutaneous fat
• Various size hemorrahages
• Small white or yellow spots
• Thick yellow fluid in digestive tract

• Isolation of bacteria is required
• Submit entire carcass or if decomposed submit wings
• Persists for weeks in bone marrow

• Timely submission of carcass important
• Collect and incinerate carcasses ASAP otherwise fluid escape

• Drain
• Enhance another area
• Add lots of water to an area to dillute bacteria
• Scare birds from site with planes

• There is no practical method of immunizing wild birds
• Vaccines and post exposure treatment used only for threatened and endangered species

• Infections in people are not common
• Maybe infected by an animal bite or scratch
• Avoid exposure to smoke from carcass fires

• Bacteria doesnt last long enough in the environment to cause major outbreaks
• Birds are the most likely carriers
• Ecology of the disease still being studied

• Limber neck
• Western duck sickness
• Duck disease

Its a bacterium which produces toxins that lead to paralysis, often fatal disease

• The bacterium persists in wetland sediments in a spore dorment form
• Resistent to heat and drying
• Viable for many seasons-yrs
• Toxin formed when bacteria germinates and multiplies

• Dead organic material
• Complete lack of oxygen
• Optimum Temp of 77 degrees

• Changes in water depth
• Fertilization of marshes with sewage or run-off
• Warm temps dead carcasses attract flies=maggots

• Many species of birds and mammals (mink)
• Water birds suffer greatest loss
• Vultures are resistant

• Lines of carcasses appearing along waters edge
• Healthy, sick & dead birds all found together
• Paralysis of muscles occur
• Death from drowning is typical

• Presumptive- symtoms in sick birds, no lesions on dead birds
• Definitive- Mouse test used for toxin, ELISA

Remove carcasses and burn them, kills maggots

• Migratory waterfowl- Avoid re-flooding of dry land in summer, avoid draw downs
• Shorebirds- drawn down water

• Waterfowl need fresh water and shade
• Inject with antitoxin
• Shorebirds few survive even with treatment prevention is better

• Humans are affected with type A or B from improperly canned foods
• Humans are fairely resistant to type C
• Thorough cooking destroys botulism in food

• Fowl Pox
• Avian diptheria
• Contagious epithelioma
• Poxvirus infection

• The virus can be mild to severe and is slow developing
• Some are host specific & Some affect several species

• By mosquitoes
• Contact with virus-food & water
• On contaminated surfaces through abraded skin

• Waterfowl
• Upland birds
• Songbirds
• Raptors
• Marine birds

• Worldwide
• Little known in wild birds
• Conditions that inhibit flies or mosquitoes can influence occurance

• Occurs all seasons of the yr
• Emergence of vector populations important

Wart like growths on feet, legs, base of beak, eye margin

• Cutaneous pox
• diphtheric or wet pox

• Presumotive- appearence
• Definitive- examination of tissues, isolation of virus, submit whole carcass, keep cool

• Lesions are self limiting
• Keep proper nutrition

• Eliminate vector breeding and resting sites
• Remove heavily affected birds
• Decontaminate food, water, perches, clothes etc.
• Live vaccines in poultry operations

Duck virus enteritis, DVE

is an acute, contagious, & often fatal disease caused by a herpes virus

• bird to bird contact
• contaminated environment
• food or water contaminated by virus in feces
• inhalation of the virus by splashing of water & from female to egg

• susceptibility varies greatly among ducks, geese, and swans.
• Ex- blue-winged teal are most susceptible, pintails are least susceptible

• was not detected in the US until 1967
• Outbreaks of DVE in the US have only been documented in Lake Andes, S. Dakota in 1973 & in the Finger Lakes region of NY in 1993.

can occur at any time of the yr, most common in April, May & June

• no prolonged illness
• sick birds are seldom seen
• time frame: incubation exposure death captive birds 3-7 days
• free living up to 14 days
• Hypersensitivity to light
• extreme thirst
• droopy head & wing
• bloody discharge from vent & bill
• ulcerative cold sore under tongue in some
• inability to fly
• convulsions
• prolapsed of the penis
• swimming in circles

duck plague virus attacks the vascular system, resulting in hemorrhaging and free blood throughout the gastrointestinal tract. Organs affected by hemorrhagic or necrotic bands include: intestine, esophagus, proventriculus (beginning of birds stomach) liver, heart, button like soars on intestinal wall, not all lesions occur in all birds.

• Presumptive characteristic lesions
• Definitive isolation & identification of the virusWhole carcass should be submitted or just the liver- should be frozen

control is difficult because carriers show no signs, sick birds spread virus through fecal material & other oral discharges, this contaminates food & water, and the environment, carcasses also release the virus

chlorinate water which increases pH, burn soil & litter

asper, brooder pneumonia (incubation) chicks & ducklings

asper is an infection of the respiratory tract, it is caused by fungi in the genus aspergillus, aspergillus fumigatus is the species most commonly involved, inhalation of aspergillus spores

• all birds probably susceptible
• mammals
• loons
• waterfowl
• raptors
• penguins

is worldwide

winter and fall in waterfowl, otherwise anytime

• emaciated
• severe & progressive difficulty in breathing
• unthrifty appearance
• wing droop
• weakness
• no escape response
• if reaches brain: loss of muscular coordination, twisting of head & neck into unnatural position, epizootic aspergillus’s possible

• various sized lesions in lungs & air sacs
• flattened yellow plaques with a cheesy appearance & consistency
• can have extensive growth of fungus on plaques and tissues.
• Acute: air sacs usually thickened
• one striking lesion
• dark red firm lungs studded with small yellow nodules

characteristic lesions, isolation of fungus

sources of spores: moldy feed, dirty brooders & incubators, moldy straw, rotting agricultural waste. Conditions for fungus growth: decomposing organic matter, warm, moist, dark environment. Other sites for growth: fields previously covered by moldy corn silage, moldy waste grain, dusty straw hay, a concern in duck boxes

those who should be careful: severe, pre-existing lung damage, cancer, anyone allergic to molds, severe reactions occur