Influence of Low and High Temperatures on the Development of Haemonchus Contortus and Oesophagostomum Columbianum Larvae in Nigeria

Abstract

EGGS of Haemonchus contortus and Oesophagostomum columbianum exposed to a constant temperature of 13.8°C at 100% relative humidity developed to the infective third stage larvae within 15 and 18 days respectively. Exposure of eggs for nine hours at 40.6°C and 100% relative humidity was lethal but development to the infective stage was achieved by culturing at 27°C after six hours of exposure at 400C and 100% relative humidity. The normal Nigerian temperature range of 13.8°C [lowest minimum for Obudu Cattle Ranch] to 40.6°C (maximum for Maiduguri) is therefore suitable for survival and development of these stronglyle eggs to the infective stages at any season in the country.