Significant Sarcoptes scabiei infestation in rabbits (Oryctolagus cuniculus): effects on physiological, apoptotic, histological, immunohistochemical, and growth performance indices.

Sarcoptes scabiei infestation (sarcoptic mange) is a common and debilitating ectoparasitic disease in rabbits, causing severe dermatological lesions and productivity losses. This study investigated the physiological, oxidative, histopathological, and immunological alterations associated with natural S. scabiei infestation in domestic rabbits. A total of 420 male weaner rabbits from farms in Giza and Cairo (Egypt) were examined from May to November 2022. Growth performance parameters, activities of antioxidant enzymes (superoxide dismutase [SOD] and glutathione peroxidase [GPx]), and the expression of inflammatory and apoptotic biomarkers were assessed. Rabbits naturally infested exhibited characteristic crusted hyperkeratotic lesions affecting the head, face, and limbs, along with a significant decline in body weight gain, feed consumption, and feed conversion efficiency when compared with the control group (p < 0.05). Markers of oxidative stress (SOD, GPx) as well as pro-inflammatory mediators (IL-1β, IL-6, and TNF-α) were significantly elevated in the infested tissues. Histological and immunohistochemical analyses revealed epidermal hyperkeratosis, mast cell infiltration, and increased CD4+ and CD8+ T-cell expression. These findings clarify the immunopathological mechanisms underlying S. scabiei infestation in rabbits and highlight its detrimental effects on physiological and performance parameters, providing a basis for improved management and control strategies.