PROPHYLACTIC ACTIVITY OF TETRACYCLINE AGAINST BRUGIA-PAHANGI INFECTION IN JIRDS (MERIONES-UNGUICULATUS)

The ability of oral tetracycline to inhibit the development of third-s tage infective larvae (L3) of Brugia pahangi to adult worms in jirds w as studied using 2 experimental protocols. Jirds treated with 1.4% tet racycline in drinking water for a period beginning 30 days before inoc ulation of L3 until 30 days postinoculation (DPI) had 97% reduction in adult worm recovery compared to untreated controls. Jirds that receiv ed 1.2% tetracycline in drinking water beginning 1 day before until ei ther 12 or 26 DPI had adult worm recoveries of 11% and < 1%, respectiv ely. Untreated jirds and those given tetracycline beginning at or late r than 13 DPI had similar adult worm recovery (27-29%). Prepatent peri ods were prolonged, and circulating microfilariae were reduced in jird s given tetracycline from 27 to 54 DPI compared to controls. These dat a indicate that tetracycline administered to jirds in drinking water i nhibits B. pahangi development from L3 to adult worms and suggest that this effect occurs during early larval development. Tetracycline admi nistered to infected jirds prior to and continuing through the onset o f patency can also affect development of microfilaremia.