Mycoplasmosis

P.M Poultry Diseases 4th year series

By Mohamed Mahmoud Salem gab AllahAssistant lecturer of pathology Faculty of Veterinary Medicine, Benha University, Moshtohor, Tukh; 13736 , Qalyuobia, EGYPT

MYCOPLASMOSIS

MG is characterized by respiratory symptoms and a prolonged course of the disease.

Particularly susceptible are hens and turkeys at all ages .

The aetiological agent is M. gallisepticum. In many cases however, the pathogenicity of the microorganism is enhanced because of its association with any or some of the following agents: E. coli, P. multocida, H. paragallinarum and IB or ND viruses. The most characteristic signs in adult flocks are tracheal rales, nasal discharge, coughing, decreased egg production .

Most outbreaks are in broiler chickens older than 4 weeks.

The course of the disease is more severe during the winter and in cases of associated infections. Often, conjunctivites, facial skin oedema and profuse tear secretion could be observed

MYCOPLASMOSIS MG is characterized by respiratory symptoms and a prolonged course of the disease.

Particularly susceptible are hens and turkeys at all ages .

The aetiological agent is M. gallisepticum. In many cases however, the pathogenicity of the microorganism is enhanced because of its association with any or some of the following agents: E. coli, P. multocida, H. paragallinarum and IB or ND viruses. The most characteristic signs in adult flocks are tracheal rales, nasal discharge, coughing, decreased egg production .

Most outbreaks are in broiler chickens older than 4 weeks.

The course of the disease is more severe during the winter

MYCOPLASMOSIS MG is characterized by respiratory symptoms and a prolonged course of the disease.

Particularly susceptible are hens and turkeys at all ages .

The aetiological agent is M. gallisepticum. In many cases however, the pathogenicity of the microorganism is enhanced because of its association with any or some of the following agents: E. coli, P. multocida, H. paragallinarum and IB or ND viruses. The most characteristic signs in adult flocks are tracheal rales, nasal discharge, coughing, decreased egg production .

Most outbreaks are in broiler chickens older than 4 weeks.

The course of the disease is more severe during the winter

MYCOPLASMOSIS In turkeys, unilateral or bilateral swelling of periorbital sinuses, nasal discharge and conjunctivitis are observed .

The inflammatory exudate is commonly fibrinous and is detected as diffuse accumulation after removal of overlying skin.

MYCOPLASMOSIS The most common gross f inding is aerosacculites, the air sacs being filled with fibrinous caseous exudate .

The majority of routine chemical disinfectants are effective against M .gallisepticum that rarely survives longer than a few days away from the host. The birds could carry the microorganism and be asymptomatic until the disease is triggered by stress factors such as change of the premise, the diet or weather, vaccinations against or infections with IB or ND, increased levels of dust or ammonia.

MYCOPLASMOSIS The most common gross f inding is aerosacculites,

the air sacs being filled with fibrinous caseous exudate .

The majority of routine chemical disinfectants are effective against M .gallisepticum that rarely survives longer than a few days away from the host. The birds could carry the microorganism and be asymptomatic until the disease is triggered by stress factors such as change of the premise, the diet or weather, vaccinations against or infections with IB or ND, increased levels of dust or ammonia.

MYCOPLASMOSIS In older cases, the content of air sacs is dense and compact. A vertical transmission is done through the eggs of some unapparent carriers. The infected progeny transmits the agent horizontally via airborne route, by coughing or contaminated forage, water and environment.

MYCOPLASMOSIS Serofibrinous pneumonias, usually bilateral, are a frequent finding

MYCOPLASMOSIS Often, the inflammation involves the adjacent serous

fibrinous polyserosites occur.

coats and thus,

MYCOPLASMOSIS Sinusites are relatively rarely observed in hens . The positive agglutination tests of sera in several birds from the flock confirm the diagnosis. MG should be distinguished from other respiratory diseases in poultry. Pulmonary and air sacs lesions could be mistaken with similar findings in E. coli septicaemia or aspergillus's.

In turkeys, P. multocida pneumonia should also be considered.

MYCOPLASMOSIS Mycoplasma synoviae (MS) infections could progress as

either acute or a chronic systemic disease with symptoms of arthritis, synovitis and bursitis especially in hens and turkeys. The earliest signs are lameness, lying down and retarded growth. Often, oedemas of tibiotarsal joints and the drumstick are observed .

The morbidity and death rates are moderate, under 10%. Young chickens at the age of 4-12 weeks and turkey poults at the age of 10-12 weeks are susceptible .

Synovites are encountered all year round, but are prevalent during cold humid seasons or when the litter is wet.

MYCOPLASMOSIS Mycoplasma synoviae (MS) infections could progress as

either acute or a chronic systemic disease with symptoms of arthritis, synovitis and bursitis especially in hens and turkeys. The earliest signs are lameness, lying down and retarded growth. Often, oedemas of tibiotarsal joints and the drumstick are observed .

The morbidity and death rates are moderate, under 10%. Young chickens at the age of 4-12 weeks and turkey poults at the age of 10-12 weeks are susceptible .

Synovites are encountered all year round, but are prevalent during cold humid seasons or when the litter is wet.

MYCOPLASMOSIS Affected birds get progressively exhausted . When the joints and tendon sheaths are open, a serofibrinous exudate

is most commonly observed .

The aetiological agent is M. synoviae. The microorganism shows a certain tropism to synovial structures as joints and tendon sheaths. An important route of dissemination of the agent is the transovarial transmission.

The distribution by a horizontal route via the respiratory tract is also possible .

The commonly used means of diagnostics is ELISA. MS infections should be differentiated from staphylococcal infections, reoviral arthritis and RGT (see RGT).

MYCOPLASMOSIS

 Clinical Description  Depression is a common sign associated with severe respiratory disease where Mycoplasma sp. play an important role.

This image shows birds from a flock positive for Mycoplasma gallisepticum and Newcastle disease virus.

 Clinical Description  Mycoplasma gallisepticum typically produces the most severe clinical signs in young birds, between the ages of 4-8 weeks. General signs may include depression, seen here, as well as reduced feed intake and poor body condition.

This image shows a chicken from a flock positive for Mycoplasma gallisepticum.

Within a flock, morbidity is usually high, however mortality is typically low unless complicated by concurrent infections and environmental stress.

 Clinical Description  The image shows a broiler breeder male with a swollen face and cyanosis of the comb, associated with Mycoplasma gallisepticum.

 Clinical Description  Ocular signs are frequently observed in Mycoplasma gallisepticum infections. These may include conjunctivitis, periorbital swelling, and eyelid edema, all of which are seen here.

 Clinical Description  Mycoplasma gallisepticum may be associated with keratoconjunctivitis and occasionally corneal opacities, seen here.

 Clinical Description  This chicken was infected with Mycoplasma gallisepticum and, on necropsy examination, showed lesions classic for MG infection including sinusitis, nasal discharge, and adhesion of the eyelids caused by conjunctivitis.

 Clinical Description  Very mild tracheitis is present in the first stages of the Mycoplasma infection.

 Clinical Description  On post-mortem exam, chickens and turkeys infected with Mycoplasma gallisepticum may have lesions distributed throughout their upper and lower respiratory tract. This image shows mild tracheitis with a small amount of mucoid exudate in the tracheal lumen.

 Clinical Description  In this bird, infected with Mycoplasma gallisepticum, there is marked inflammation and congestion of the trachea and catarrhal exudate can been seen in the tracheal lumen.

 Clinical Description  In Mycoplasma gallisepticum infections, mucoid to caseous exudate may be seen in nasal passages, sinuses, trachea, and bronchi.

This image shows plugs of exudate in the lumen of the trachea and bronchi.

 Clinical Description  In Mycoplasma gallisepticum infections, fibrinous pneumonia may be observed in the lungs.

 Clinical Description  In Mycoplasma gallisepticum infections, pericarditis and fibrinous pneumonia (shown here) are often a common sequelae of MG infection when it becomes complicated with E. coli infection.

 Clinical Description  Normal air sacs are completely transparent.

However, this picture shows a mild postvaccine reaction to Mycoplasma that could be present in healthy birds.

 Clinical Description  Mild airsacculitis with light presence of foam.

 Clinical Description  Airsacculitis with caseous exudate and increased vascularization.

 Clinical Description  Severe airsacculitis with abundant foam and aggregates of caseous exudate.

 Clinical Description  In Mycoplasma gallisepticum infections, fibrinous airsacculitis, with accumulations of caseous exudate, may also be observed on the air sacs, as seen here.

This is a common sequelae of MG infection when it becomes complicated with E. coli and will result in high condemnations at processing plants.

 Clinical Description  Caseous exudate is frequently observed on the airsacs of birds infected with Mycoplasma gallisepticum, as shown here.

 Clinical Description  The heart of a chicken infected with MG is shown on the right and is compared to a normal heart on the left.

Severe fibrinous accumulations can be observed.

 Clinical Description  In Mycoplasma gallisepticum infections, fibrinous pericarditis and perihepatitis are frequently found on post-mortem exam.

These lesions are a common sequelae of MS infection when it becomes complicated with concurrent E. coli infection.

 Clinical Description  Concurrent infections, such as colibacillosis, are frequent in chronic Mycoplasma infections. This image shows severe perihepatitis and pericarditis. The highest morbidity and mortality in Mycolplasma infections is usually associated with the presence of concurrent infections and environmental stress, which exacerbate the underlying disease.

 Clinical Description  In Mycoplasma gallisepticum infections, fibrinous or fibrinopurulent pericarditis and perihepatitis may also be found on postmortem exam, as seen here.

 Clinical Description  In Mycoplasma gallisepticum infections, fibrinous pericarditis is a common sequelae of MG infection when it becomes complicated with E. coli. Here, a normal heart is shown on the right and a heart from a chicken with MG infection is shown on the left.

 Clinical Description  In Mycoplasma gallisepticum infections, fibrinous pericarditis and peritonitis, as observed in this image, are also often a common sequelae of MG infection when it becomes complicated with E. coli.

These lesions will result in high condemnations at the processing plant.

 Clinical Description  In Mycoplasma gallisepticum infections, the fibrinous inflammation surrounding the heart, lungs, and liver may become so extensive that it extends into the surrounding coelomic cavity. In the MG infected bird on the bottom of this photo, the inner breast muscle covering the heart and lungs is covered in fibrin.

ORGAN : leg of chickens LESIONS : Swelling of the hock and toe joints (Arthritis).

SUSP.DIS. : Mycoplasmosis

ORGAN : Leg of bird LESIONS : Exudates in foot pad.

SUSP.DIS. : Mycoplasmosis

ORGAN : Wing joint LESIONS : Swelling (Arthritis).

SUSP. DIS. : Mycoplasmosis

 Clinical Description  Fibrinous airsacculitis and perihepatitis can be seen in the chicken embryo on the right, following inoculation with Mycoplasma gallisepticum.

 Clinical Description  The isolation and identification of Mycoplasma organisms is commonly performed by culturing swabs collected from the trachea or sinuses.

Here, a tracheal swab sample is being collected.

 Clinical Description  Serology is one of the easiest and accurate ways to monitor and diagnose Mycoplasma. This image shows vials of chicken serum. The serum in the left vial was collected properly, whereas the middle and right vials show hemolysis. High quality samples are very important to ensuring accurate laboratory testing.

 Clinical Description  A preventative treatment is one of the best ways to control Mycoplasma infections in broilers. This image shows a healthy broiler that received antimycoplasma treatment during the first days after hatch.

 Clinical Description  Table egg layers are frequently positive to Mycoplasma infections.

 Clinical Description  Table egg layers could be an important reservoir for Mycoplasma infections.

ORGAN : Turkey carcass LESIONS : Poor growth and poor feathering SUSP.DIS. : Mycoplasmosis

 Clinical Description  In turkeys, Mycoplasma gallisepticum often produces a more severe infection than in chickens.

Here, a turkey is exhibiting characteristic severe swelling of the infraorbital sinuses. The combination of sinusitis and conjunctivitis may become so severe that the bird cannot open its eyes. This sign is not commonly observed in chickens.

 Clinical Description  In turkeys, sinusitis may be unilateral, as seen here, or bilateral. While there are other causes of sinusitis affecting poultry, Mycoplasma gallisepticum infection should be strongly suspected and ruled out with appropriate diagnostic testing.

 Clinical Description  This turkey is showing classic signs of infection with Mycoplasma gallisepticum, including sinusitis and conjunctivitis.

ORGAN : LESIONS : SUSP.DIS. :

Head of turkey Swelling of infraorbital sinus Mycoplasmosis

ORGAN : LESIONS : SUSP.DIS. :

Opened infraorbital sinus of turkey Sticky exudates Mycoplasmosis

ORGAN : Chest cavity of chicken LESIONS : Pericarditis and air saculitis SUSP. DIS. : Mycoplasmosis

ORGAN : Chest cavity of chicken LESIONS : Air saculitis and pneumonia SUSP.DIS: Mycoplasmosis