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

LIFE CYCLE - Psoroptes ovis

• Eggs laid on skin at the edge of lesion
• Hatch in 2-3 days
• Larvae feed for 2 – 3 days
• Moult to Nymphal stage – last 12 has is a state of lethargy
• Nyphal stage lasts 3-4 days – Before moult -lethargic period -36 hrs
• Smaller nymphs will become adult
• Pubescent female appear before males on the 5^th day and the males on the 6^th day- copulation takes place
• Pubescent females molt to become ovigerous
• Life cycle from egg to egg- 12 days
• Adult female live 30-40 days and each lay 90-100 eggs