Influence of Rearing Temperatures on Oviposition and Survivability of Developmental Stages of Culicoides peregrinus Vector of Bluetongue Virus with a Note on Egg Viability

Temperature influence on development and larval survivability of Culicoides peregrinus Kieffer (Diptera: Ceratopogonidae), a vector of bluetongue virus (BTV), was assessed at five rearing temperatures (15 °C, 20 °C, 26 °C, 30 °C and 35 °C), a photoperiod of 13L:11D, and relative humidity of 75%. The higher and lower threshold temperatures and developmental success of life stages during rearing were ascertained and corroborated with the seasonal abundance. Rearing temperatures significantly influenced the number of viable eggs laying by females and larval survivability. Most oviposited eggs and larval survivability (> 80%) were observed at 26 °C and the least (8%) was recorded at 35 °C. Development of immatures ceased at 15 °C. The duration from egg to adult stage was shorter (10–12 days) at 35 °C compared to that recorded at 26 °C (18–23 days). This study will be useful in the establishment of a laboratory colony of this vector species thereby, contributing to our understanding of the vectorial capacity, competence and continual supply of viable eggs throughout the year.