Table 4.

Preventive efficacy of various macrocyclic lactones against the macrocyclic lactone-resistant heartworm strain JYD-34

Study	Treatment	Route of administration	Dosage (µg/kg)	Day of inoculationa	Days of treatment	Preventive efficacy (%)	References
1	Placebo	SC	0	−30	0	–	[54]
	ProHeart 12 (moxidectin)	SC	500	−30	0	100	[54]
	Heartgard Plus (ivermectin)	Oral	Min. 6	−30	0, 30, 60, 90, 120, 150	10.5	[54]
	Interceptor Plus (milbemycin oxime)	Oral	Min. 500	−30	0, 30, 60, 90, 120, 150	14.6	[54]
2	Placebo	SC	0	165	0	–	[54]
	ProHeart 12 (moxidectin)	SC	500	165	0	98.3	[54]
	Heartgard Plus (ivermectin)	Oral	Min. 6	165	0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330	37.7	[54]
	Interceptor Plus (milbemycin oxime)	Oral	Min. 500	165	0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330	34.9	[54]
3	Placebo	Oral	0	−30	0, 30, 60, 90, 120, 150	–	[49]
	Moxidectin	Oral	24	−30	0, 30, 60, 90	95.9	[49]
	Moxidectin	Oral	24	−30	0, 30, 60, 90, 120, 150	99.3	[49]
	Heartgard Plus (ivermectin)	Oral	Min. 6	−30	0, 30, 60, 90, 120, 150	63.9	[49]
	Interceptor Plus (milbemycin oxime)	Oral	Min. 500	−30	0, 30, 60, 90, 120, 150	54.6	[49]

^aEach dog inoculated with 50 third-stage larvae (L3) of the JYD-34, macrocyclic lactone-resistant strain