Fipronil and ivermectin treatment of cattle reduced the survival and ovarian development of field-collected Anopheles albimanus in a pilot trial conducted in northern Belize

Table 3 Ovarian development and blood digestion in Anopheles albimanus surviving 4 days after feeding on cattle

	Pre-treat	Day 2	Day 5	Day 7	Day 14
Untreated heifers (n = 2)
Fully gravid	78 ± 14%	80 ± 16%	91 ± 7%	78 ± 16%	86 ± 8%
Complete blood meal digestion	91 ± 10%	100%	91 ± 7%	93 ± 10%	99 ± 7%
No. mosquitoes dissected	N = 32/n₁ = 27, n₂ = 5	N = 25/n₁ = 12, n₂ = 13	N = 64/n₁ = 29, n₂ = 35	N = 27/n₁ = 11, n₂ = 16	N = 80/n₁ = 40, n₂ = 40
Fipronil-treated heifers (n = 3)
Fully gravid	83 ± 15%	^a N = 2/n₁ = 2, n₂ = 0, n₃ = 0	0%	0%	25 ± 6%
Complete blood meal digestion	96 ± 8%		100%	100%	100%
No. mosquitoes dissected	N = 23/n₁ = 7, n₂ = 7, n₃ = 9		N = 7/n₁ = 0, n₂ = 4, n₃ = 3	N = 11/n₁ = 1, n₂ = 3, n₃ = 7	N = 165/n₁ = 47, n₂ = 53, n₃ = 65
Ivermectin-treated heifer (n = 1)
Fully gravid	50%	50%	50%	^a N = 2	60%
Complete blood meal digestion	75%	75%	63%		90%
No. mosquitoes dissected	N = 4	N = 4	N = 8		N = 77

^aToo few (N = 2) mosquitoes survived engorgement to make meaningful estimates. N = total number of surviving mosquitoes dissected within a treatment group; n = number of surviving mosquitoes dissected per heifer within a treatment group. Complete blood meal digestion was defined as the percentage of mosquitoes without visible evidence of blood in their midguts when excised and examined microscopically 4 days after engorgement. Fully gravid was defined as the percentage of mosquitoes with fully developed Stage V ovaries 4 days after engorgement

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