PRIMARY RESULTS OF STUDY ON USING MESOCYCLOPS AS a PREDATOR IN DHF CONTROL in SOUTHERN PROVINCES

Tran Khanh Tien, Tran Huu Hoang et al.

Pasteur Institute of HCH City

In 1989, Mesocyclops were revealed first in 13 Northern provinces and used successfully as a predator to kill the larvae of Aedes aegypti in Hung Yen.

Study on the presence and the distribution of Mesocyclops in Southern provinces indicated that:

§ There were 749 water containers in 12/15 (80%) study sites in 9 provinces having mesocyclops.

§ Percentage of water containers:

With Mesocyclops: 4,73%

With larva of Aedes aegypti: 28,97%

With fish: 3,91%

Without Larvae, fish, and Mesocyclops.: 62,39%

§ The main species of Mesocyclops:

Mesocyclops aspericornis: 41,17%

Mesocyclops thermocyclopoides: 29,41%

Mesocyclops ruttnerii: 17,64%

Mesocyclops klieferi and other Mesocyclops: 11,78%.

§ Results of study in laboratory:

One female Mesocyclops laid 15 ± 3 nauplii each time

After 2 ± 1 day Mesocyclops laid one time

Life cycle (nauplii to nauplii): 12±2 days.

Percentage of nauplii turning into adult Meso.: 16,66%.

Predatory potency of Meso. against the larvae of Aedes aegypti

No.	Species	No. of tests	No. of I instar larvae	No. of eaten larvae/ 24 hours	No. of killed larvae	Total of deaths
1 2 3	M.asper. M.rutt. Control	12 18 12	600 900 600	29,77 23,83 0	8,88 13,16 0	38,65 36,99 0