Host gill attachment causes blood-feeding by the salmon louse (Lepeophtheirus salmonis) chalimus larvae and alters parasite development and transcriptome

Table 3 Distribution of preadult Lepeophtheirus salmonis at 18 days post-infestation

Group of lice	Experiment 1				Experiment 2
Group of lice	All	Body	Fins	Gills	All	Body	Fins	Gills
Pad I of total	68 (294)	88 (228)	49 (40)	30 (26)	66 (329)	87 (206)	63 (55)	38 (62)
Female of pad I	33 (102)	30 (68)	78 (31)	8 (2)	35 (115)	30 (62)	87 (48)	0 (0)
Pad I on filament	10 (29)	5 (12)	25 (10)	27 (7)	21 (69)	6 (12)	38 (21)	58 (36)
Pad I with visible blood	16 (48)	13 (30)	0 (0)	69 (18)	24 (80)	13 (27)	0 (0)	85 (53)
Pad I on filament with visible blood in intestine	1 (2)	0 (0)	0 (0)	8 (2)	9 (30)	0 (0)	0 (0)	48 (30)

Notes: Preadult (pad) I lice sampled from 10 and 9 fish (Experiment 1 and 2, respectively) were investigated in more detail. The percentage and absolute numbers (in parentheses) of pad I lice sampled from all body parts of the fish (all) and separated into different sampling places (body, fins, gills) are shown for Experiment 1 and 2. The table shows the overall percentage of pad I of all lice (pad I and chalimus II), what percentage of these were females, the percentage of pad I lice found on a filament, the percentage of lice with visible blood in the intestine as well as the percentage of pad I lice with both, blood filled intestine and a filament

ISSN: 1756-3305