Inconspicuous post-mortem findings in rabbits from Switzerland naturally -infected with Rabbit Haemorrhagic -Disease...

Area of Science:

• Veterinary Virology
• Pathology
• Rabbit Health

Background:

• Rabbit Haemorrhagic Disease Virus 2 (RHDV-2) emerged in 2010 and has largely replaced RHDV in Switzerland.
• RHDV-2 causes acute viral hepatitis with high mortality in rabbits.
• Gross pathological findings for RHDV-2 are not well-documented.

Purpose of the Study:

• To analyze clinical and pathological findings in rabbits naturally infected with RHDV-2.
• To compare gross and histological lesions between RHDV-2 positive and negative rabbits.
• To raise awareness of RHDV-2 as a differential diagnosis for sudden rabbit deaths.

Main Methods:

• Analysis of 35 rabbit anamnesis and necropsy reports (March 2015-May 2017).
• Reverse transcriptase real-time polymerase chain reaction (RT-qPCR) for RHDV-2 and RHDV detection.
• Histological examination of liver, lung, and kidney in RHDV-2 positive cases.

Main Results:

• 25 out of 35 rabbits tested positive for RHDV-2; none for RHDV.
• Increased mortality reported in 89% of RHDV-2 positive cases versus 33% in negative cases.
• Histological lesions were most severe in the liver, followed by lung and kidney; gross pathology lacked pathognomonic signs.

Conclusions:

• RHDV-2 infection in rabbits often presents with non-specific gross findings, potentially masked by gastro-intestinal disease or septicaemia.
• Histological examination is crucial for identifying RHDV-2-associated lesions.
• Clinicians and pathologists should consider RHDV-2 in cases of sudden rabbit death and confirm with laboratory diagnostics.