| dc.description.abstract | Clinical and pathological investigations on camel skin diseases were undertaken in
Turkana, Samburu, Isiolo and Marsabit districts in northern Kenya between October 1990
and November 1991. Nomadic camel herds were selected based on accessibility. The origin,
domestication, population, distribution, socio-economic importance, constraints to
development of camel husbandry in Kenya, and diseases of the camel (emphasizing on the
skin diseases) are reviewed.
Out of 11,196 camels examined, 53.2 per cent had skin diseases/lesions. All camel
herds were found to be infested by ticks and camel flies at varying levels of infestation. The
commonest and most widespread diseases were Mange (45.7 per cent), camelpox and skin
abscesses (20.1 and 17.4 per cent respectively). In addition to the previously known
Sarcoptes scabiei var cameli ,four other new mite species were found.
The first of these was a minute 'beetle-like' mite christened Cardiocephaloptes
marti, new genus and species (new sub-order and new family). This is a tiny lymph
sucking mite, about half the size of S. scabiei. The body is shaped like that of a beetle. It has
a large falsehead which is shaped like the sign of a heart on a playing card with the pointed
end facing anteriorly. The male is only three quarters the size of the female. The first and
third pairs of legs are similar in both sexes, but there is a marked difference in the other two
pairs. Leg two in the male has a characteristic lanceolate appendage sticking out laterally
between the femur and the genu, w• hereas in the female it is somewhat shrivelled. Leg four
in the male is short, large and bears a powerful claw, shaped likethe dewclaws of a lion,
and long straight setae whereas in the female it has only three segments, at the end of which
there is a pair of long whiplike setae which are equal in length.
The second and third were large-sized mites belonging to the family dermanyssidae.
Camelonyssus golfer, (new genus and species) is a blood sucking mite which bears
strong resemblance to members of the genus Dermanyssus except that it has a single long
chelicera without chela while the former have two which are both armed with chelae. The
gnathosome is so minute as to be absent, being completely masked by the enormous pair of
pedipalps and the retractile chelicera. The mite has four pairs of legs each bearing a sucker
xii i
borne on a short unjointed stalk. The stalk and sucker together look like the distal end of a
golf club, with the bulb facing posteriorly. Camelonyssus samburu (new genus and
species) is also a blood sucking mite similar to C. golfer in having a single tubular needlelike
chelicera which has no chela at the end. However, it is smaller in size than C. golfer
although it has a large gnathosome which bears three pairs of long sharp spikes and a long
protruding chelicera. Each pedipalp also bears a single spike which is similar to that of the
capitulum. All legs have club-shaped suckers which contain a Y-shaped chitinous thickening
and the unjointed stalk is short.
The identity of the fourth mite species, the Baragoi 'Louse-mite', of which only
one specimen with broken legs was available, has not yet been established except to say it is
unlike any mite seen in the literature. Its body is shaped like a bowling pin with the smaller
end being the falsehead. The mouthparts are complex and consist of five pairs. The first
anterior/outer pair is shaped like pincers with curved bodies and needle-sharp ends. The
second pair, which is also curved in conformity with and lies immediately behind the first
one, is composed of a lateral half of thick solid chitin ending in a sharp point, while the
medial half consists of vanes like in a birds' feather. The third pair resembles the second but
is smaller and more blunter. The last two pairs are similar in structure and arrangement,
being rod-shaped with sharp anterior ends. The other peculiarity of the mite is a pair of
antenna-like structures at the rear end, enclosing a short pair of knob-like structures.
All the five mite species caused similar lesions and responded favourably to treatment
with 60 per cent Diazinon (Neocidal® Ciba-Geigy).
The point prevalence rate of ticks on camels was ~00 per cent amongst the nomadic
pastoralist herds throughout the study period. The sites commonly infested with ticks were
the nostrils, sternal, inguinal and anal regions, eyelids, ears, tail and interdigital spaces. In
camel calves nymphs were spread allover the body surface and in adults, along the
backbone. On parts of the body covered by thick hairs, nymphs could only be detected on
palpation. Evidence of tissue damage was common on predilection sites. This was due to
tick bite and the resulting irritation and in some cases, infection and abscessation ensued.
Ticks attached on the eyelids caused excessive irritation which resulted in marked
lacrimation. One argasid or soft tick was identified as an Ornithodorus species and the
following Ixodid or hard ticks were identified:-Amhlyomma gemma, Hyalomma dromedarii;
H. truncatum; H. impeltatum, H. albiparmatum, H. detritum, H. marginatum rufipes,
Rhipicephalus punctatus, R. pulchellus, and R. pravus .. Of all the ten tick species
identified, male ticks were more abundant than female ticks. Very few engorged female ticks
were encountered. Thick and thin blood smears examined from 426 camels were negative
for tick-borne haemoparasites known to be endemic in other species of livestock in the area.
There was total elimination of ticks from camels treated with two percent Cypermethrin
high-cis (Ectopor®, Ciba-Geigy) at three weeks intervals.
The prevalence of skin necrosis was 6.2 per cent and was usually found occurring in
outbreaks affecting several animals at once. The lesions were first noted as firm and painful
swellings which later burst leaving ulcers of raw flesh.
The incidence of dermatomycoses was 4.3 per cent. Ringworm, dermatophilosis,
sporotrichosis and other miscellaneous fungi were found and are described. The following
microoganisms were identified: Aspergillus niger, A. nidulans, Candida albicans,
Cladosporium species, Dermatophilus congolensis, Fusarium oxysporum, F. solani, Mucor
species, Scopulariopsis species, Trichophyton species, and Trichosporon glabrata.
Myiasis was not encountered in live animals but five camel carcasses examined at
Isiolo abattoir were found to harbour the third-stage larvae of the camel nasal bot fly, -
Cephalopina titillator, although the animals appeared in good health during antemortem
inspection.
Camel-flies, Hippobosca came/ina were found in all camel herds except those treated
with Ectopor. Other flies were very common and numerous around the manyattas where
they attacked all livestock species. Camels suffering or recovering from pox were
particularly vulnerable and were severely disturbed by these flies. Recommendations based
on the findings and conclusions of this study are given. | en |
