Respiratory Illnesses

Here are the 10 more common respiratory illnesses in poultry (all the mycoplasmas are lumped together). Of the 10, only 2 can be completely treated with antibiotics and 1 must run it’s course. All the others are not curable and birds will remain carriers, infect any new birds introduced and you run the risk of spreading the disease to someone else’s flock.

Birds who present with respiratory symptoms should be tested ASAP to ensure the safety of your flock and those flocks that you may come in contact with indirectly.

Home treatment is not recommended unless you have confirmed what you are dealing with. Members need to be using antibiotics appropriately to avoid creating antibiotic resistance and to avoid putting other birds at risk.

A list of Vets and Diagnostic Labs can be found in UNIT 4 (this list is a work in progress).

1. Aspergillosis (Brooder Pneumonia) – NO EFFECTIVE TREATMENT

• Cause: Common fungus called Aspergillus fumigatus, sources of which may include moldy, wet feed; wet bedding; or mold on hatching eggs. Infection occurs when birds inhale large numbers of fungal spores, producing severe inflammation in birds’ lungs, air sacs, and sometimes other tissues. Can affect birds of all ages.
• Clinical Signs:
  • Gasping
  • Gurgling
  • Bluish-purple discoloration of the face
  • Paralysis
  • Torticollis
  • Death
• Diagnosis: Respiratory tract cultures and/or microscopic examination of the affected tissues.
• Treatment and prevention: Treating individual birds is usually ineffective, very expensive, and not practical. In affected flocks, remove the mold source to prevent new infections. Clean up and disinfect the coop.

1. Avian/Fowl Cholera (Pasteurella multocida) – CAN BE TREATED WITH ANTIBIOTICS

• Cause: Bacterial infection from Pasteurella multocida, which can be acquired from exposure to sick wild waterfowl or rodents in the poultry area or through bite injuries from predators that carry these bacteria in their saliva. The disease can be further spread through fighting in the birds. Usually affects birds over 6 weeks old.
• Clinical Signs:
  • Darkened head
  • Swollen head and wattles
  • Paralysis
  • Lethargy
  • Reduced feed consumption
  • Reduced egg production
  • Abscesses in multiple tissues
  • Pneumonia
  • High death loss
• Diagnosis: Bacteria must be cultured in a laboratory from blood samples, abscesses, or dead birds.
• Treatment and prevention: Treat the flock with an appropriate antibiotic (ideally based on culture and drug sensitivity information) for at least 10 days. Predator and rodent control is also necessary. Pick up and dispose of dead birds. Clean up and disinfect the coop.

1. Avian/Infectious Coryza – NO EFFECTIVE TREATMENT

• Cause: Infectious Coryza is an acute respiratory infection of chickens caused by the Gram-negative, non-motile bacteria Avibacterium paragallinarum (formerly called Haemophilus paragallinarum). A. paragallinarum is not a particularly resistant bacterium. It is destroyed by most disinfectants, desiccation, and direct exposure to sun light. There are 3 serotypes of A. paragallinarum: A, B and C which is very important when immunizing the birds against this disease. Infectious Coryza does not present a zoonotic risk (the disease does not spread from birds to humans). In addition, human consumption of meat or eggs derived from birds contaminated with Avibacterium paragallinarum presents no risk for human health. Birds that have recovered from the disease can harbor the bacteria for a long time (or permanently) in the absence of any clinical sign (asymptomatic carriers). For this reason, the disease can be difficult (or impossible) to eliminate in those facilities lacking an all-in all-out practice. Traditionally, layers are kept in multiage complexes and infectious coryza can be a challenge when bringing young pullets that have never been exposed to the organism in the past. Exposure of naïve birds to birds that have been infected previously is perhaps the most common mechanism for disease transmission in regions where infectious coryza is prevalent. The organism can spread via inhalation from aerosols or be ingested from contaminated feed or water. Equipment moved from one house into another may also transport infective bacteria.
• Clinical signs:
  • Sinuses distended with exudate
  • Swollen head and wattles
  • Sneezing
  • Coughing
  • Reduced feed consumption
  • Reduced egg production
  • Abscesses in multiple tissues
  • Death, low unless complicated by E.coli or MG
• Diagnosis: Isolation of the organism. This can be done plating the samples on blood agar plates cross streaked with a Staphylococcus culture following overnight culture at 37C in anaerobiosis. Hemagglutination Inhibition and PCR are also available.
• Treatment and prevention: *A. paragallinarum *is susceptible to several antibiotics which can be given in water. Tetracyclines are commonly used for treatment. If the disease is not endemic in a given area for infectious coryza, depopulation may be used to decrease the likelihood of passing the disease to future flocks. If this is not an option, avoid bringing replacement birds into the same premises while sick or recovered birds are present. After the affected flock is removed, clean and disinfect the premises and wait at least 3 weeks before repopulating.If the disease becomes wide-spread in a region, there are commercial bacterins (a type of vaccine made with inactivated bacteria) available. This vaccine must match the serotype of A. paragallinarum isolated from previous local outbreaks. 2 doses of the vaccine should be given well before the onset of lay and several weeks before moving the birds into a high-risk location.

1. Avian Influenza – NO EFFECTIVE TREATMENT

• Cause: Type A influenza virus of birds, which is most often present in wild and domestic waterfowl and shore birds. Infection is occasionally transmitted to poultry. Two forms of the illness occur: highly pathogenic avian influenza (HPAI) and low pathogenic avian influenza (LPAI). LPAI sometimes produces minimal illness in infected birds, but HPAI is very lethal to chickens, turkeys, and upland gamebirds. Disease must be reported to the state veterinary office.
• Clinical signs are highly variable but may include:
  • Drops in egg production
  • Hemorrhages on the body and comb
  • Coughing
  • Sneezing
  • Rales
  • Swelling of the face and/or wattles
  • Bluish-purple discoloration of the face
  • General diarrhea
  • Red or white spots on the legs and comb
  • Conjunctivitis
  • Sometimes high death loss
• Diagnosis: Antibodies can be detected with a blood test. Tests that detect the virus from respiratory and cloacal swabs are also available.
• Treatment and prevention: Prevent direct or indirect contact with domestic or wild waterfowl (such as geese or ducks) and their droppings. Avoid high-risk practices such as visiting live bird markets and bird auctions. Recovered flocks will continue to shed the virus. Depopulation is required for some types of mildly pathogenic AI because the virus has the ability to mutate to a more pathogenic form. When the highly pathogenic form is detected, national and international regulations require strict quarantine and rapid destruction of all infected flocks. The AI virus can remain viable for long periods of time at moderate temperatures and can live indefinitely in frozen material. No vaccines are available for use in the U.S.

1. Colibacillosis – CAN BE TREATED WITH ANTIBIOTICS

• Cause: Colibacillosis, also called mushy chick disease and cellulitis, is infection by the **Escherichia coli (E. Coli) **bacteria. This disease affects all poultry as well as wild birds. E. coli is the most common bacterial pathogen in poultry. It is spread through fecal contamination of eggs, feed, and water. It is often the cause of secondary infection when the immune systems of birds in a flock are compromised due to another disease, especially mycoplasma.
• Clinical Signs:
  • Failure to thrive
  • Diarrhea
  • Respiratory problems
  • Lameness
  • Low performance in older birds due to tumors
  • High mortality in younger birds due to yolk-sac infections
  • High embryotic mortality in breeder flocks
• Diagnosis:
• Treatment and prevention: Antibiotics can be used to treat infection. A vaccine is available for breeders and layers. To prevent infection on your farm or ranch, purchase only mycoplasma-free stock from hatcheries registered with the National Poultry Improvement Plan (NPIP) registered hatcheries.

1. Fowl Pox Infection – MUST RUN IT’S COURSE

• Cause: Birds become sick with the pox virus through contact with sick birds or infected scabs in the environment. Mosquitoes can also transmit fowl pox.
• Clinical Signs:
  • Rales
  • Coughing
  • Discharge from the eyes
  • Sneezing
  • Retarded growth
  • Warts or scabs
• Diagnosis: Typical nodules and scabs can be seen on featherless tracts of skin on the face, wing web, and feet, and often take 3-4 weeks to heal and fall off. Nodules can sometimes develop in the mouth and trachea. This form, called “wet pox” is difficult to recognize and may cause affected birds to die from suffocation.
• Treatment and prevention: Keep a closed flock (no new birds of any age or species introduced to the present flock from outside sources) and control mosquitos. Clean up and disinfect the coop. A very effective vaccine is available that can prevent the illness or stop the existing infection from spreading if detected early.

1. Infectious Bronchitis (IBV) – NO EFFECTIVE TREATMENT

• Cause: An avian coronavirus.
• Clinical Signs:
  • Rales
  • Gasping
  • Discharge from the eyes
  • Discharge from the nose
  • Reduced egg production
  • Production of thin-shelled or wrinkled eggs
  • Sometimes death loss in very young chickens
• Diagnosis: Blood test. Some animal laboratories can attempt isolation of the virus from necropsy specimens.
• Treatment and prevention: Only supportive care can be provided once the flock is ill. For prevention, keep a closed flock, away from other poultry. Clean up and disinfect of the coop. Vaccines are also available.

1. Infectious Laryngotracheitis (ILT) – NO EFFECTIVE TREATMENT

• Cause: An avian herpesvirus. Chickens over 14 weeks old are more susceptible.
• Clinical Signs:
  • Coughing
  • Sneezing
  • Head shaking
  • Rales
  • Gasping
  • Discharge from eye and/or nose
  • Swelling of the face and/or wattles
  • Retarded growth
  • General diarrhea
  • Conjunctivitis
  • Prostration
  • Coughing up bloody mucus
  • High death loss may be seen
• Diagnosis: High death loss and coughing up blood (if present) are very suggestive of ILT. Submit sick or dead birds to the Animal Diagnostic Laboratory.
• Treatment and prevention: A very effective vaccine is available that can prevent the illness or stop the existing infection from spreading if detected early. Vaccination prior to taking birds to poultry shows (no less than one month before the show) is highly recommended. A tissue-culture-origin vaccine should be used. Recovered birds may remain virus carriers and continue to spread the infection among susceptible chickens.

1. Mycoplasma gallisepticum (MG), Mycoplasma synoviae (MS), Mycoplasma meleagridis (MM) – NO EFFECTIVE TREATMENT

• Cause: This bacteria infects chickens, turkeys, and upland game birds. Turkeys are the most vulnerable to infection, while chickens sometimes carry this bacteria without showing signs. Spread by bird-to-bird contact or contact with infectious respiratory secretions. Once infected, a bird remains infected for life. Infected breeders also transmit this bacteria into the hatching egg, causing chicks to hatch with the infection.
• Clinical Signs:
  • Coughing – MG, MM
  • Sneezing – MG, MS,MM
  • Head shaking – MG, MS
  • Rales – MG, MS, MM
  • Gasping – MG
  • Discharge from eye and/or nose – MG, MS
  • Swelling of the face and/or wattles – MG, MS
  • Retarded growth – MG, MS, MM
  • General diarrhea – MG
  • Prostration – MG
  • Drop in egg production – MG
  • Pneumonia – MG
  • Infected sinuses and air sacs – MG
  • Lameness – MS
  • Green, watery diarrhea – MS
  • Swollen joints – MS
  • Torticollis – MM
• Diagnosis: Clinical signs, blood testing
• Treatment and prevention: The effects of the disease can be reduced with certain antibiotics. Vaccines are also available. For prevention, keep a closed flock and only purchase birds that have tested negative for the disease.

1. New Castle Disease – NO EFFECTIVE TREATMENT

• Cause: Newcastle disease, also called ND or pneumoencephalitis, is caused by paramyxovirus. The highly contagious and lethal form of Newcastle disease is known as viscerotropic velogenic Newcastle disease, or VVND. (The term *viscerotropic *indicates that the virus attacks the internal organs; *velogenic *indicates that the disease is highly pathogenic.) VVND is also referred to as exotic Newcastle disease or Asiatic Newcastle disease. Newcastle disease affects all birds of all ages. In humans and mammals, the virus causes mild inflammation of the eye. The Newcastle virus can be transmitted through the air within short distances. Sick birds can transfer the virus directly to flock mates through body secretions and fecal material. The virus can also contaminate shoes, persons who work with or near birds, tires, dirty equipment, feed sacks, crates, and so on, and be transmitted from flock to flock. Wild birds are another source of infection. The Newcastle virus is transmitted through the egg, but infected embryos typically die before hatching.
• Clinical Signs:
  • Coughing
  • Sneezing
  • Shaking head
  • Rales
  • Gasping
  • Discharge from the eyes
  • Discharge from the nose
  • Swelling of the face and/or wattles
  • Bluish-purple discoloration of the face
  • Retarded growth
  • General diarrhea
  • Green watery diarrhea
  • Torticollis
  • Conjunctivitis
  • Prostration
  • Decreased feed/water consumption
  • Decreased egg production
• Diagnosis: Clinical signs, blood testing
• Treatment and prevention: There is no specific treatment for Newcastle disease. Antibiotics can be given for three to five days to prevent secondary bacterial infections (antibiotics do not affect viruses). Increasing the brooding temperature for chicks by 5°F may help reduce losses. Prevention programs should include vaccination, good sanitation, and implementation of a comprehensive biosecurity program.

References/Resources:

https://articles.extension.org/…/poultry-diseases-of…

https://extension.psu.edu/respiratory-diseases-of-small…

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