A comparison between intraperitoneal injection and intranasal and oral inoculation of mink with Aleutian mink disease...

Area of Science:

• Veterinary Virology
• Infectious Disease Modeling
• Animal Health Research

Background:

• Aleutian mink disease virus (AMDV) causes significant losses in mink farming.
• Effective inoculation methods are crucial for studying AMDV pathogenesis and developing control strategies.
• Previous studies have explored various routes for AMDV infection, but optimal methods for research purposes require further evaluation.

Purpose of the Study:

• To compare the efficacy of different inoculation routes for establishing Aleutian mink disease virus (AMDV) infection in American mink.
• To evaluate the reliability of various sample types (blood, saliva, feces, rectal swabs) for detecting AMDV infection.
• To assess the development of viremia and antibody response following different inoculation methods.

Main Methods:

• Thirty-five American mink were inoculated via intranasal (IN), intranasal with sedation (INS), oral, or intraperitoneal (IP) routes with a local AMDV isolate.
• Blood, saliva, rectal, and fecal samples were collected at multiple time points post-inoculation (dpi).
• Viral DNA was detected using PCR, and antibodies were measured by counter-immunoelectrophoresis (CIEP). Histopathology was performed on key organs at 56 dpi.

Main Results:

• All inoculation routes successfully established AMDV infection, confirmed by viral DNA detection in spleen, lungs, and lymph nodes at 56 dpi.
• Intraperitoneal (IP) and intranasal with sedation (INS) routes led to earlier and more consistent detection of viral DNA and antibodies in plasma by 36 dpi.
• Oral and intranasal (IN) routes resulted in some animals remaining seronegative by 56 dpi, indicating lower efficacy for consistent infection establishment.
• Saliva, rectal, and fecal samples were unreliable for detecting AMDV infection.
• Histologic lesions consistent with Aleutian disease (AD) were observed in most mink across all groups.

Conclusions:

• The intranasal route with sedation (INS) is the most effective and reliable method for experimentally establishing Aleutian mink disease virus (AMDV) infection in mink without breaching anatomical barriers.
• INS inoculation facilitates consistent viral DNA detection and antibody production, crucial for research and diagnostic studies.
• Viremia can be transient, highlighting the importance of timely sample collection, while antibody production is a more persistent indicator of infection in seroconverted animals.
• Non-invasive sample types like saliva and feces are not recommended for accurate AMDV infection diagnosis in experimental settings.