Table 2 The number of unheated (UHt) negative Dirofilaria immitis antigen (Ag) test results from dogs submitted to a moxi-doxy therapy (10% imidacloprid + 2.5% moxidectin and doxycycline hyclate) that became Ag positive after a sample heat (Ht) pre-treatment

UHt Ag negative

14

21

14

2

First Ht Ag Negative

8

12

2

–

Second Ht Ag Negative^a

–

8

12

2

Total Ht Ag positive/ total UHt Ag negative (%)

6/14 (42.9%)^a

1/21(4.8%)^b

0/14 (–)

0/2 (–)