Avian Diseases for Concern

Disease

Description

Type of Pathogen

Symptoms & Signs

Methods of Spread

 *Avian Influenza (AI)

There are two types of AI:

• Low-pathogenicity AI

• High-pathogenicity AI

Respiratory disease of birds with wildfowl being the natural reservoirs.

Few clinical signs present; H5 & H7 strains are closely monitored because of their ability to mutate into high pathogen form

Fatal form of the AI

Orthomyxo Virus

(See Above)

(See Above)

Severity varies (see below)

• Slight facial swelling
• Respiratory distress
• Minimal mortality

• Sudden & high death loss
• Purple discoloration of wattles, combs legs
• Diarrhea
• Incoordination
• Nasal discharge, sneezing, coughing
• Decreased egg production

• Direct contact between birds
• Respiratory secretions
• Feces
• Contaminated litter
• Contaminated clothing and equipment
• Wild waterfowl are natural reservoirs

Coronavirus Infection

Found predominately in pheasants. Birds affected may show no signs.

Virus

• Diarrhea
• Lethargy

• Respiratory tract
• Feces

*Duck Virus Enteritis: DVE

“Duck plague”

Affects wild & domestic ducks, geese, and swans. Ducklings are most susceptible. (Blue-winged teal most susceptible; Pintail duck least susceptible)

Herpes Virus

• Excess thirst, dehydration
• Weakness
• Diarrhea
• Blood-stained vent
• Lesions of vascular, digestive, lymphoid systems

• Contact with wild waterfowl
• Infected birds
• Contaminated Environment

* Exotic Newcastle Disease (END)

One of the most fatal infectious, contagious diseases in the world; so deadly that many birds die before showing symptoms. However, virus can be destroyed by dehydration or sunlight.

ParamyxoVirus

• Partial or complete drop in egg production
• Misshapen or thin egg shells
• Greenish, watery diarrhea
• Muscular tremors
• Paralysis
• Gasping for air, nasal discharge, coughing, sneezing
• Sudden death loss

• Direct contact between birds
• Bodily discharges of infected birds
• Contaminated clothes, equipment, & vehicles

Fowl Pox

Best prevented by vaccination. Can occur in 2 types: wet pox or dry pox

Pox Virus

Dry Pox:

• yellow warts on combs & wattles Wet Pox:
• yellow lesions in mouth or on trachea
• difficulty swallowing & breathing

• Infected birds
• Carrier birds
• Mosquitoes, biting insects

Marek’s Disease

Very contagious disease. Affects organs of the lymphoid system of young, sexually immature chickens 2-7 months old.

Herpes Virus

• Partial paralysis (wings, legs, neck)
• Blindness, irregular shaped pupils (gray eye)
• Multiple skin lesions
• Tumors in nerve, organ, muscle, liver, lymphoid tissues

• Airborne transmission
• Inhalation of feather dander, dust, or litter
• Infected birds

* Infectious Laryngotracheitis (ILT)

Respiratory infection that affects chickens, pheasants, & peafowl. Spreads rapidly.

Herpes Virus

• Respiratory distress
• Coughing, sneezing
• Conjunctivitis
• Facial swelling

• Infected birds
• Carrier birds
• Contaminated clothing, shoes, & equipment

* Avian Tuberculosis (TB)

Slow-spreading, chronic infection that is found worldwide. Can survive in soil for years. It can infect swine, sheep, rabbits, rodents, calves & humans.

Bacteria

• Diarrhea
• Progressive wasting; emaciation
• Pale coloration of comb, wattles, & face
• Lesions in liver, spleen, intestines, other organs

• Contaminated environment
• Feces
• Bird to Bird contact

Fowl Cholera

Respiratory disease that affects many species of domestic, wild, & zoo birds. Can occur in chronic or acute form. High morbidity with acute form.

Bacteria

• Swollen eyes & wattles
• Anorexia/ decreased appetite
• Decreased egg production
• Swelling of joints
• Mucus discharge from mouth or nose

• Bird to bird contact
• Contaminated clothing & equipment
• Contaminated feed and water

Disease

Description

Type of Pathogen

Symptoms & Signs

Methods of Spread

• Salmonellosis

• • Fowl Typhoid

• • Pullorum Disease

Lives in the intestinal tract of affected birds and causes intestinal disruption. Salmonella enteritidis & Salmonella typhimurium are not host specific, normally affecting birds under 6 weeks old.

Affects semimature flocks. Very similar to Pullorum disease. Caused by salmonella gallinarum bacteria.

Egg transmitted disease that occurs primarily in chickens, pheasants, ducks, geese & guinea. Usually, no signs are apparent in adult birds. Caused by salmonella pullorum bacteria.

Bacteria

• Anorexia
• White diarrhea, pasting around vent
• Huddling near heat sources
• Increased mortality by 5th day
• Swollen joints
• Poor feathering

• Anorexia
• Poor growth
• White diarrhea, pasting around vent
• Wing droop

• Anorexia
• Lethargy
• Depression
• Shivering
• Fever

• Infected eggs & birds
• Feces
• Contaminated food

• Infected & hatching eggs
• Infected birds
• Feces
• Contaminated Feed

• Direct contact
• Contaminated feed
• Environment

Blackhead

Affects chickens, turkeys, & peafowl. Can be transferred by intermediate hosts (cecal worms and earthworms).

Protozoa

• Depression
• Yellow diarrhea
• Ruffled feathers
• Dark-colored head parts

• Contaminated water, feed, & droppings
• Indirect transmission by infected eggs
• Environment

Coccidiosis

Lives and multiples in the intestinal tract. Results in high mortality. Can be greatly reduced by housing birds in a sunny dry area.

Protozoa

• Bloody droppings
• Ruffled feathers
• Huddling
• Decreased appetite
• Pale combs

• Feces
• Contaminated clothing & equipment
• Infected litter

Internal Parasites Roundworms Hairworms

Cecal Worms Tapeworms

Can be tranfered by intermediate host, such as beetles and insects. Avoided by regular deworming

Internal Parasitic

• Anemia
• Emaciation
• Stunted Growth
• Decreased egg production

• Infested soil
• Inadequate deworming schedule
• Ingestion of infected feces

Lice

Avoided by cleaning facilities & equipment between flocks. Are most common during fall & winter. Eggs and mature lice can be view by naked eye on feathers.

Lives only on host.

External Parasite

• Anemia
• Malnutrition
• Weight loss

- Bird to bird contact

Northern Fowl Mite

Avoided by regularly cleaning area that houses birds. Lives on host and in the environment.

External Parasite

• Blackened feathers
• Scabby skin around vent

• Infested egg flats
• Infested facilities
• Bird to bird contact

Scaly Leg Mite

Should isolate affected birds. Treat by dipping legs in

warm acaricidal solution (contact veterinarian). Lives on the host and in the environment.

External Parasite

- Scaly and crusty legs, combs, & wattles

• Infested egg flats
• Bird to bird contact

Curled Toe Paralysis

Can affect all birds but young chicks are most susceptible.

Nutritional

• Curled toes
• Hyperextension of Legs
• Lameness

- Riboflavin (B2) deficiency

Encephalomalacia

“Crazy chick Disease”

Nutritional

• Swollen brain
• Inability to walk
• Falling sideways when trying to stand

- Lack of vitamin E

Rickets

Can affect all birds. Avoided by feeding a balanced ration.

Nutritional

• Inability to stand
• Soft pliable legs and beaks
• Beading of ribs

- Imbalance of Calcium (Ca), Phosphorus (P), and/or vitamin D3