Infectious sinusitis of turkeys (Mycoplasma gallisepticum)
A flock of turkeys arrives at the slaughterhouse, presenting 30% of the animals affected with a respiratory process localized within the upper respiratory tract. The animals showed a severe sinusitis of the infraorbital sinuses accompanied by facial edema, conjunctivitis and nasal discharge. Two heads were submitted, from which swabs were collected. A PCR against Mycoplasma gallisepticum was performed, with a positive result, and a RT-PCR against avian Metapneumovirus (aMPV) with a negative result.
Thus, a diagnosis of infectious sinusitis of the turkey was confirmed, which is caused by M. gallisepticum. This infection produces respiratory disease in broilers, laying hens and turkeys, the latter being more susceptible. It produces:
- Congestion and catarrhal exudate in nasal cavity, trachea, bronchi, and air sacs, producing nasal discharge.
- Some degree of pneumonia.
- In severe and chronic respiratory infections can cause fibrinous airsacculitis and fibrinous pericarditis and perihepatitis, associated with high mortality and condemnations in the slaughterhouse.
- The infection is frequently exacerbated by viral infections (aMPV, infectious bronchitis virus…) or complicated by bacterial infections (mainly coli) resulting in an increased severity and mortality of the disease. This process is called Chronic Respiratory Disease (CRD).
- Turkeys: ocular secretions precede the development of the sinusitis of the infraorbital sinuses, presenting mucoid to caseous exudate.
- Chickens: it may cause keratoconjunctivitis, characterized by facial and eyelid swelling, increased lacrimation and conjunctival congestion.
In affected flocks, M. gallisepticum affects most of the animals, producing respiratory signs in 80-90% of the turkeys, but they do not exhibit sinusitis consistently (1-70% of the animals). (AC)