Transportation and Routine Veterinary Interventions Alter Immune Function in the Dog.

Area of Science:

• Veterinary immunology
• Animal physiology
• Stress response in animals

Background:

• The acute stress response involves the hypothalamic-pituitary-adrenal axis and sympathetic nervous system, interacting with the immune system.
• Limited data exists on how these stress responses affect immunological parameters in pet dogs within clinical settings.

Purpose of the Study:

• To investigate the effects of travel, instrumentation, and hospitalization on the immunological parameters of pet dogs.
• To evaluate alterations in immune cell function and expression markers due to common veterinary procedures and environments.

Main Methods:

• Blood samples were collected from healthy dogs in a home environment (control) and at presentation, post-instrumentation, and 24 hours after hospitalization.
• Assessed immune parameters included toll-like receptor 4 (TLR4) expression, major histocompatibility complex class II (MHCII) expression on neutrophils and monocytes, peripheral blood mononuclear cell cytotoxicity, and neutrophil apoptosis.

Main Results:

• Lipopolysaccharide (LPS)-induced downregulation of toll-like receptor 4 (TLR4) was blunted in stressed dogs.
• Neutrophil and monocyte MHCII expression increased post-transport but normalized after hospitalization.
• Peripheral blood mononuclear cell cytotoxicity was reduced in stressed dogs, and neutrophil apoptosis increased, though it decreased after hospitalization.

Conclusions:

• Travel and hospitalization significantly alter key immunological parameters in pet dogs, including immune cell function and receptor expression.
• These stress-induced changes should be carefully considered when interpreting immunologic data from clinical studies involving pet dogs.
• While some immune responses normalized post-hospitalization, the initial impact of stress is notable.