|
|
Addis Ababa University Libraries Electronic Thesis and Dissertations: AAU-ETD! >
Faculty of Veterinary Medicine >
Thesis - Tropical Veterinary Epidemiology >
Please use this identifier to cite or link to this item:
http://hdl.handle.net/123456789/658
|
| Title: | INVESTIGATION ON ECTOPARASITES OF SMALL RUMINANTS IN SELECTED SITES OF AMHARA REGIONAL STATE AND THEIR IMPACT ON THE TANNING INDUSTRY |
| Authors: | SERTSE, TEFERA |
| Advisors: | Dr. Abebe Wossene |
| Keywords: | Ectoparasites
Skin defects
Skin Quality
Sheep
Goats
Tannery
Amhara |
| Copyright: | 2004 |
| Date Added: | 21-Apr-2008 |
| Abstract: | The objectives of this study were to determine the prevalence of ectoparasites on sheep and
goats, assess the effect of major ectoparasites on the quality of skin processed in the tanneries
and identify the type and magnitude of defects that cause down grading and rejection in
pickled sheep and wet blue goat pelts. The study was carried out through questionnaire survey,
clinical examination and analysis of pickled and wet blue skin defects in Kombolcha and
Dessei tanneries. Out of 752 sheep and 752 goats examined 50.5% of sheep and 56.4% of
goats were found infested with one or more ectoparasites. The major ectoparasites identified on
sheep were D. ovis (38.5%), M. ovinus (12.5%), tick infestations (3.4%) and Linognathus spp.
(2.4%). The major ectoparasites recorded on goats were Linognathus spp. (28.3%), ticks
(22.2%), sarcoptic mange (6.1%) and Ctenocephalides spp (8.1%). In sheep, there was
significant difference (p<0.001) in prevalence of M. ovinus and D. ovis, between lowland and
highland and midland and highland. There was also significant difference in prevalence of
Linognathus spp. between midland and lowland (p<0.01) and tick infestations between
lowland and midland (p<0.01), and between lowland and highland (p<0.001) but no significant
difference (P>0.05) was detected in prevalence of sarcoptic mange and Ctenocephalides spp.
In goats, the risk of sarcoptic mange infestation in lowland (Odds ratio (OR) =4.6, p<0.001)
and midland (OR=5.0, p<0.05) was 4.6 times and 5.0 times, respectively higher than the
highlands. There was also significant difference in prevalence of Linognathus spp between
lowland and highland (p<0.01) and Ctenocephalides spp. infestations between midland and
highland (p<0.001) and between midland and lowland (p<0.001) agro climate, the risk being
higher in midland. Both in sheep and goats no significant difference (p>0.05) was recorded in
prevalence of all ectoparasites except D. ovis infestation by age. D. ovis was found to affect
more significantly (p<0.05) the adults (42.2%) than the young (29.9%) sheep. Analysis of body
condition showed no significant variation (p>0.05) to ectoparasite infestation in sheep.
However, poor body condition goats were 4.3 times at risk from sarcoptic mange (OR=4.3,
p<0.001), Linognathus spp. (OR=2.1, p<0.001) and tick (OR=1.6, p<0.05) infestation than
good body condition goats. The prevalence of M. ovinus was significantly higher in wooly
sheep (41.2%) than wooly sheared (0.8%) and hairy (0%) indicating the importance of wool
size for the parasite abundance. The prevalence of ‘ekek’ at pickled stage on each group of 20
pickled sheep pelts infested with D. ovis and M. ovinus and each group of 20 pickled goat pelts
x
infested with sarcoptic mange and Linognathus spp. were 100% and 95% and 100% and nil
respectively. However, the prevalence on apparently free control groups 20 sheep and 20 goat
pelts were 15% and nil respectively. There was a strong association (p<0.001) between ‘ekek’
and infestation of sheep with M. ovinus and D. ovis and infestation of goats with sarcoptic
mange. Besides this, the severity of infestation of sheep with D. ovis and M. ovinus and goats
with sarcoptic mange were found to correlate significantly (p<0.05) with severity of ‘ekek’
defect. Study on 1000 pickled sheep pelts and 1000 wet blue goat pelts indicated ‘ekek’ was
the predominant defect both in pickled sheep (70.8%) and wet blue goat pelts (42.3%)
followed by scratch, scars and technical defects. There was significant difference (OR=3.3,
p<0.0001) in proportion of ‘ekek’ between pickled sheep and wet blue goat pelts. Moreover, a
strong association (p<0.001) was observed between ‘ekek’ and scratch, and ‘ekek’ and scars
both on pickled sheep and wet blue goat pelts. The economic loses due to drop in quality of
exported skin in Kombolcha and Dessie tanneries because of ‘ekek’ was estimated to be 1.6
million for pickled sheep and 0.6 million for wet blue goat pelts per year. Favorable climates,
poor level of management, poor awareness of farmers and poor animal health extension
services are believed to have contributed for widespread occurrences of ectoparasites. The
increasing threat of ectoparasites to small ruminant production and the tanning industry
necessitate urgent control intervention. |
| Description: | A thesis submitted to Faculty of Veterinary Medicine, Addis Ababa University in partial
fulfillment of the requirement for the Degree of Master of Science in Tropical Veterinary
Epidemiology |
| URI: | http://hdl.handle.net/123456789/658 |
| Appears in: | Thesis - Tropical Veterinary Epidemiology
|
Items in the AAUL Digital Library are protected by copyright, with all rights reserved, unless otherwise indicated.
|
