# Table 1 Geometric mean flea counts and percent efficacy relative to nontreated controls for dogs treated with a selamectin topical spot-on, a spinosad/milbemycin oxime oral tablet or a spinosad only oral tablet

Day 0 Day 7 Day 14 Day 21 Day 28
Treatment1 Mean # of fleas2,3 % control4 Mean # of fleas % control Mean # of fleas % control Mean # of fleas % control Mean # of fleas % control
24 hours post-treatment or infestation
Non-treated Control 26.38a   46.39a   35.99a   28.85a   51.46a
Selamectin 10.45a 60.4 0.12b 99.7 1.52b 95.8 0.62b 97.9 3.62b 93.0
Spinosad-Milbemycin 0.00b 100.0 0.00b 100.0 0.12c 99.7 1.29b,c 95.5 7.85b 84.7
Spinosad 0.00b 100.0 0.00b 100.0 0.12c 99.7 2.19c 92.4 13.96b 72.9
48 hours post-treatment or infestation
Non-treated Control 36.25a   38.71a   24.40a   33.81a   30.81a
Selamectin 3.10b 91.4 0.00b 100.0 0.12b 99.5 0.12b 99.6 1.33b 95.7
Spinosad-Milbemycin 0.00c 100.0 0.00b 100.0 0.00b 100 0.41b 98.8 3.86b,c 87.5
Spinosad 0.00c 100.0 0.00b 100.0 0.26b 98.9 0.44b 98.7 7.31c 76.3
1. 1 Each of 6 dogs in the control group received no treatment. Each of 6 dogs in the Selamectin topical spot-on, Spinosad/Milbemycin oxime oral tablet or a Spinosad only oral tablet groups were administered the formulations according to label directions on Day 0.
2. 2 Each dog was infested with 100 adult Ctenocephalides felis from the KS1 strain on days -2, 7, 14, 21 & 28.
3. 3 Geometric mean # of fleas recovered from dogs per treatment group.
4. 4% control = ((geometric mean count control -geometric mean count treatment)/ geometric mean count control)) × 100.
5. a,b,c geometric means within a column with unlike letter superscripts are significantly different (P <0.05).