VPA 221: Veterinary Entomology and Acarology (1+1)

CATTLE FOLLICULAR MITE

Demodex bovis

Condition : Papulonodular form

• Population of 100s to 1000s mite/follicle results in dilated follicle-leads to dermal papules or cysts
• As they enlarge they can be felt beneath skin
• Lesion concentrate in anterior part of cows, notably neck, shoulders , axillary region, udder
• Papular cysts enlarge to form granulomatous nodules-when follicular opening gets blocked by mites, keratin and other debris
• Usually seen in cows stressed by pregnancy/ lactation
• Dilated nodules vary in size from a pin head to a chicken egg
• Larger modules rupture to produce suppurative sores
• The pus like exudate (consistency of tooth paste) when examined will reveal the presence of  large numbers of D. bovis

Economic Loss

• Skin damage-defects in leather
• Tanning industry loss- due to diminished quality of processed cow hide
• D.tauri -another species recorded in Czechoslovakia