MODE OF CONTAMINATION OF DOGS BY ADULT FLEAS (CTENOCEPHALIDES-FELIS) IN DIFFERENT CONTROLLED ENVIRONMENTS

The study was designed to quantify the contamination of dogs by adult fleas in various controlled environments simulating those of the norma l domestic dog. Two groups of 5 dogs were used : one was infested and other one was an uninfested control group. They were placed in two ide ntical 3.4 m square rooms with concrete floors and smooth cement walls . In each room, an area was laid with straw which was not renewed. Thi s area served as a bed for the dogs and an environment for the develop ment of fleas. The remaining space, used for exercise, was cleaned dai ly. A third identical room, but devoid of straw, was employed as a mee ting room between infested and uninfested dogs. After each encounter, the floor and walls were decontaminated with a flame thrower. When an infested dog is put with an uncontaminated one in a decontaminated roo m, there was limited transfer of fleas from the infested dog (harborin g 10-85 fleas) to the uninfested animal : 0-3 fleas after 2 hours and 3-6 fleas after 24 hours contact. When an uninfested dog is placed in a room which had contained for one month dogs harboring an average of 22 fleas it picked up a mean of one flea within two hours and 4.6 flea s in 24 hours. An uninfested dog placed in a contaminated room contain ing five infested dogs (harboring an average of 21 fleas each) picked up a mean of 1.2 fleas in 2 hours and 6.2 fleas in 24 hours. On introd uction of an infested dog (harboring an average of 62 fleas) into a co ntrolled environment, an average of 5 fleas were lost within 2 hours ( each uninfested dog picked up an average of 1 flea) and lost a mean of 13.4 fleas in 24 hours (a mean of 2.7 fleas picked up by each uninfes ted animal).