UNIVERSITY OF NAIROBI
COLLEGE OF AGRICULTURE AND VETERINARY SCIENCES
FACULTY OF VETERINARY MEDICINE
LECTURE NOTES: JPM3258/AAS 204: GENERAL PARASITOLOGY
LECTURE SERIES: ENTOMOLOGY
1.0 FAMILY: HIPPOBOSCIDAE
1.1 Classification
1.2 General Features of Hippoboscidae
● Members of this family are parasitic on mammals and birds.
● It has two important genera, Hippobosca (Forest flies) and
Melophagus (M. ovinus - Sheep ked).
● The adults are flattened dorso-ventrally; the abdomen is soft and
leathery with indistinct segmentation.
● They have piercing and sucking mouth-parts.
● They have strong craws on the legs, which allow them to cling on
hairs and feathers.
● They are permanent ectoparasites and remain on their hosts for
long periods.
● They have one pair of wings except Melophagus that is wing-less
(as seen in the illustrations below).
,1.3 Economic importance of Hippoboscidae
1. Their bites are itchy leading to scratching, biting and rubbing with
resultant damage to the skin and fleece and may predispose the
host to myiasis.
These are important causes of lowered quality of hides and skins,
poor health and deaths.
2. They suck blood and when in large numbers cause anaemia leading
to ill health and possible deaths.
3. There are costs incurred in their control.
2.0 FLEAS, BUGS AND LICE
2.1 Simple classification of arthropods
2.2 Order Siphonaptera (Fleas)
● Members of this order are commonly referred to as fleas.
, ● Fleas are not very host specific and can feed on any warm-blooded
animal when a suitable host is not immediately available.
● The important species and their respective hosts are shown in the
table below.
Species Host
Ctenocephalides canis Dogs
Ctenocephalides felis Cats
Tunga penetrans (Jiggers) Pigs and man
Echidnophaga gallinacea (stick tight flea) Chicken
Pulex irritans Man
Xenopsylla cheopis Rats
g
● Although domestic ruminants have no fleas that are specific to
them, they can suffer infestation by those from the other animals
where they may even cause deaths especially in young and
malnourished animals.
(a) Geographical distribution of fleas
● Fleas occur in all parts of the world including Kenya
(b) Identification of fleas
● Fleas are small, dark brown, wingless insects with laterally
compressed bodies.
● They measure about 1 to 4mm in length.
● The mouth parts are adapted for piercing the skin and sucking
blood.
● Some species have ctenidia/combs (see illustration) which are
important features used for their identification.
, ● The third pair of legs is much longer than others (as seen in the
illustration) and adapted for leaping.
(c) Life cycle of fleas
● Fleas undergo complete metamorphosis.
● Females lay eggs on the ground or on the host which hatch to
release the first larval stage (L1) in 4 days.
● The larvae moult twice to reach the third stage larvae (L3) in about 2
weeks.
● The L3 then pupate by spinning a cocoon around itself before the
adult emerges (as seen in the illustration) in 3 to 4 weeks.
(d) Economic importance of fleas
COLLEGE OF AGRICULTURE AND VETERINARY SCIENCES
FACULTY OF VETERINARY MEDICINE
LECTURE NOTES: JPM3258/AAS 204: GENERAL PARASITOLOGY
LECTURE SERIES: ENTOMOLOGY
1.0 FAMILY: HIPPOBOSCIDAE
1.1 Classification
1.2 General Features of Hippoboscidae
● Members of this family are parasitic on mammals and birds.
● It has two important genera, Hippobosca (Forest flies) and
Melophagus (M. ovinus - Sheep ked).
● The adults are flattened dorso-ventrally; the abdomen is soft and
leathery with indistinct segmentation.
● They have piercing and sucking mouth-parts.
● They have strong craws on the legs, which allow them to cling on
hairs and feathers.
● They are permanent ectoparasites and remain on their hosts for
long periods.
● They have one pair of wings except Melophagus that is wing-less
(as seen in the illustrations below).
,1.3 Economic importance of Hippoboscidae
1. Their bites are itchy leading to scratching, biting and rubbing with
resultant damage to the skin and fleece and may predispose the
host to myiasis.
These are important causes of lowered quality of hides and skins,
poor health and deaths.
2. They suck blood and when in large numbers cause anaemia leading
to ill health and possible deaths.
3. There are costs incurred in their control.
2.0 FLEAS, BUGS AND LICE
2.1 Simple classification of arthropods
2.2 Order Siphonaptera (Fleas)
● Members of this order are commonly referred to as fleas.
, ● Fleas are not very host specific and can feed on any warm-blooded
animal when a suitable host is not immediately available.
● The important species and their respective hosts are shown in the
table below.
Species Host
Ctenocephalides canis Dogs
Ctenocephalides felis Cats
Tunga penetrans (Jiggers) Pigs and man
Echidnophaga gallinacea (stick tight flea) Chicken
Pulex irritans Man
Xenopsylla cheopis Rats
g
● Although domestic ruminants have no fleas that are specific to
them, they can suffer infestation by those from the other animals
where they may even cause deaths especially in young and
malnourished animals.
(a) Geographical distribution of fleas
● Fleas occur in all parts of the world including Kenya
(b) Identification of fleas
● Fleas are small, dark brown, wingless insects with laterally
compressed bodies.
● They measure about 1 to 4mm in length.
● The mouth parts are adapted for piercing the skin and sucking
blood.
● Some species have ctenidia/combs (see illustration) which are
important features used for their identification.
, ● The third pair of legs is much longer than others (as seen in the
illustration) and adapted for leaping.
(c) Life cycle of fleas
● Fleas undergo complete metamorphosis.
● Females lay eggs on the ground or on the host which hatch to
release the first larval stage (L1) in 4 days.
● The larvae moult twice to reach the third stage larvae (L3) in about 2
weeks.
● The L3 then pupate by spinning a cocoon around itself before the
adult emerges (as seen in the illustration) in 3 to 4 weeks.
(d) Economic importance of fleas
