Efficacy of four commercially available heartworm preventive products against the JYD-34 laboratory strain of Dirofilaria immitis

Table 4 Adult D. immitis recovered at necropsy

Treatment group	Animal ID	Male D. immitis	Female D. immitis	Total D. immitis
Ivermectin/Pyrantel	IDF-2	2	3	5
(Group 1)	UHH-2	12	3	16 ^a
	VTH-2	10	5	15
	IOF-2	12	2	14
	BFG-2	5	7	13 ^a
	PXC-2	6	8	15 ^a
	VVH-2	12	7	19
	GSC-2	5	8	13
Total				110
Milbemycin/Spinosad	FCG-2	6	1	7
(Group 2)	IUE-2	2	0	3 ^a
	UDH-2	9	4	14 ^a
	VCG-2	3	1	4
	TPH-2	6	8	15 ^a
	XBH-2	7	4	12 ^a
	EZG-2	4	3	8 ^a
	KUH-2	11	7	18
Total				81
Selamectin	OFF-2	7	9	17 ^a
(Group 3)	VUH-2	4	4	9 ^a
	EYE-2	6	2	9 ^a
	UKG-2	4	8	13 ^a
	AVG-2	9	5	15 ^a
	GPG-2	12	4	16
	ZXG-2	13	5	18
	GDE-2	7	3	11 ^a
Total				108
Imidacloprid/Moxidectin	DIH-2	0	0	0
(Group 4)	UYH-2	0	0	0
	CGH-2	0	0	0
	FKC-2	0	0	0
	FJC-2	0	0	0
	VZG-2	0	0	0
	LAG-2	0	0	0
	THH-2	0	0	0
Total				0
Non-treated Control	UTH-2	5	11	17 ^a
(Group 5)	GKC-2	7	7	15 ^a
	TWH-2	9	9	18
	EDG-2	9	8	18 ^a
	RAF-2	6	15	21
	CRC-2	11	7	18
	TJH-2	4	9	13
	IXG-2	19	13	32
Total				152

^aIntact heartworms were enumerated by gender. If worm pieces/ fragments were also recovered, one additional worm was added to the count for that dog