Some factors affecting the sporogony of theileria parva in the salivary glands of its tick vector, rhipicephalus appendiculatus
Abstract
An investigation into several aspects of Theileria parva
sporogony in unfed Rhipicephalus apoendiculatus ticks was carried out
in the laboratory and in the field. In the first experiment an
attempt was made to heat-stimmulate sporogony in unfed nymphal ticks
infected with I.parva parva Kilae and I.,P.parva Muguga. Heat
stirrulation of unfed adult ticks was also undertaken. The
effectiveness of high ambient terTperatures and of feeding on rabbits
as stirrulants to sporozoite maturation in I.parva-infected adult
ticks were compared. Heat stimmulation of sporogony in adult ticks
under natural conditions in the field at a high altitude area (2,100m)
was attempted. Finally, the rate of transmission of I.parva
sporozoites to cattle after heat stirrulation of sporogony in adult
ticks was investigated.
The study established the following three facts:
1. Unfed nyrrphal B,.apoendjculatus ticks infected with I.,Q.parva
o
Kilae can deyelop mature sporozoites if exposed to 37 C and high
relative humd+ty for'-4-days.
2. Unfed adult B,.appendiculatus ticks, infected with I.Q.parva
Kilae and I.Q. parva Muguga, exposed .to -'natural conditions in the
field at Muguga, Kenya can develop mature sporozoites.
3. Heat stirrulated B,.appendiculatus adults infected with
I.Q.parva Kilae can transmit the parasite to susceptible cattle
- - within 24 hours of attachment.
xii
The study also confinmed previous findings that exposure of
o
R.appendicuJatus to 37 C is not as efficient in stinuJatingI.parva
parva sporogony as is feeding the ticks on rabbits. Another observation
made was that I.Q.parva Kilae seems to be more sensitive to heat
stimulationthan I.Q.parva Muguga.
Citation
MSc.Publisher
School of Biological Sciences, University of Nairobi
Description
Master of Science