Pathologic changes in pigeons infected with a virulent Trichomonas gallinae strain (Eiberg)

Area of Science:

• Veterinary Pathology
• Parasitology
• Avian Diseases

Background:

• Trichomonas gallinae is a flagellate parasite affecting pigeons.
• The Eiberg strain is known for its virulence and hepatotropic nature.
• Initial infection occurs in the digestive tract, progressing to systemic involvement.

Purpose of the Study:

• To investigate the pathological effects of Trichomonas gallinae (Eiberg strain) in pigeons.
• To document the timeline of organ damage and disease progression.
• To understand the mechanisms leading to mortality.

Main Methods:

• Histopathological examination of infected pigeon livers.
• Macroscopic and microscopic observation of pathological changes.
• Monitoring of clinical signs and survival rates post-infection.

Main Results:

• Early vascular congestion and perivascular cuffing in the liver by day 4 post-infection (PI).
• Fatty degeneration of hepatocytes by day 7 PI, preceding necrosis and parasite presence in lesions by day 8 PI.
• Development of caseous lesions delineated by inflammatory cells and significant hepatosplenomegaly.
• Degeneration observed in kidneys and genitalia, likely secondary to liver dysfunction.
• Mortality in nonimmune pigeons occurred within 14–17 days PI due to liver failure.

Conclusions:

• Trichomonas gallinae infection leads to severe liver pathology and multi-organ dysfunction in pigeons.
• The parasite's progression involves initial digestive tract infection, systemic spread, and significant hepatic damage.
• Understanding these pathological changes is crucial for managing trichomoniasis in pigeon populations.