Prevalence and Risk Factors Associated to Skin Diseases in Small Ruminants in Gamo Gofa Zone, South-Western Ethiopia
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Vol. 9(8), pp. 228-234, August 2017 DOI: 10.5897/JVMAH2015.0375 Article Number: E9251B465489 Journal of Veterinary Medicine and ISSN 2141-2529 Copyright © 2017 Animal Health Author(s) retain the copyright of this article http://www.academicjournals.org/JVMAH Full Length Research Paper Prevalence and risk factors associated to skin diseases in small ruminants in Gamo Gofa zone, south-Western Ethiopia Bereket Molla1*, Haba Haile2,3 and Sefinew Alemu2 1The Donkey Sanctuary Working Worldwide, Ethiopia Program, Ethiopia. 2 University of Gondar, Gondar, Ethiopia. 3 Gofa Universal College, Department of Animal Health, Sawla, Ethiopia. Received 25 February 2015; Accepted 27 May 2015 A cross-sectional study was employed to estimate the prevalence of skin diseases in small ruminant and risk factors associated to its occurrence in Gamo Gofa zone from July, 2012 to April, 2014. The study areas were clustered into two agro-ecological zones; lowland and highland area. A total of nine hundred (450 sheep and 450 goats) were examined. Detailed physical examinations and systemic examinations, followed by skin scraping and laboratory tests were carried out to diagnose skin diseases. The Pearson’s chi-square (χ2) test was used to assess the degree of association between skin diseases and risk factors. The overall prevalence was found to be 42.33% (381/900). Significantly higher prevalence (p<0.05) of small ruminant skin disease was observed in goats (52.22%) than sheep (38.66%). Furthermore, the study also revealed significantly higher prevalence (p<0.05) in unvaccinated (42.92%) than vaccinated (29.52%) group of animals. The occurrence of skin diseases was statistically significantly associated with age and sex of animals. The prevalence was higher in males (30.38%) than females (22.49%), and in young age groups as compared to adults. The external parasites identified include manges (Sarcoptic, Chorioptic, Psoroptic and Demodectic), ticks (Ambyloma varigatum, Rhipicephalus evertisi evertisi and Boophilus decloratus), lice (Bovicola species and Linognathus species) and sheep ked (Melophagus ovinus). Viral infections, predominantly of pox virus infection were noted in sheep (10.44%) and goat (13.11%) and contagious ecthyma 2.44% on sheep and 2.00% on goats. The overall prevalence of viral disease showed significant association (p<0.05) with vaccination history and age of the study animals. The high prevalence of skin disease on small ruminant has shown there is urgent need for its strategic prevention and control, as skin and hides represent the second major export commodity of the country. It is recommended that external parasite control should be strategically designed and technologically verified in local context. Key words: Ethiopia, external parasites, Gamo Gofa, goat, sheep, prevalence. INTRODUCTION Small ruminants contribute 35 and 14% of meat and milk consumption, respectively in Ethiopia (Kebede, 2013). *Corresponding author. E-mail: [email protected]. Tel: +251 913 09 6857. Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 4.0 International License Molla et al. 229 Hide and skin export has got the largest share of animal risk factors in different parts of the country, it is not known products next to live animal export and skin is the most in Gamo Gofa zone of Southern Ethiopia. Furthermore, important item in generating foreign currency, next to this area is known to border with the major pastoral coffee (Kumsa et al., 2012). Ethiopia supplies a wide livestock production area of South Omo zone, and range of both processed and semi-processed sheep and serving as a route of market from the lowland pastoral goat skins to the world market (Kebede, 2013). Whereas production areas to the highland meat value chain areas hides and skins account for 12 to 16% of the total value of highland markets. In due concern to the above facts, exports in Ethiopia (Tefera, 2012). The current utilization and to seek as whether there is need and/or serve as of hides and skins is estimated to be 48% for cattle hide, baseline information, this study was initiated. The 75% for goat skin and 97% for sheep skin with the objectives were to estimate the prevalence and assess expected off take rate of 33% and 75% for sheep, goat associated risk factors of skin diseases, and to determine and cattle, respectively (Berhe, 2009; Yacob et al., 2008 the etiological agents of skin diseases in small ruminants. and Tefera, 2012). In Ethiopia, hides, skins, leather and leather products are the most widely traded agro-based livestock commodities with an estimated value of over MATERIALS AND METHODS US$100 billion/year and continues to conspicuously Study area exhibit a huge unexplored potential (Mekonnen et al., 2013). Even though small ruminants are important The study was conducted on three districts, categorized into two components of Ethiopian farming system, their agro-ecological zones, namely Demba Gofa and Zala district, contribution to food production, rural income and export representing lowland, and Geze Gofa district for highland. Lowland income are far below the expected potential (Mekonnen categories were areas ranging from 800 to 1500 meter above sea level (masl) but those ranging from 1500 to 2800 masl were et al., 2013). This is because small ruminant production considered as highland. The average annual rainfall of the study not only in Ethiopia but in most of the developing areas were varying from 950 to 1150 mm, characterized by a bi- countries is constrained by complemented effects of modal type of distribution. The mean annual minimum and prevailing diseases, subclinical parasitism, poor feeding maximum temperature were 15.4°C and 37.2°C in the highland and and managements (Abadi, 2000; Singla, 1995; Tefera, lowland, respectively. 2012; Yacob et al., 2008; Yacob, 2013). Over the last 10 years, there are indications that the quality of raw material has deteriorated with an increasing number of Study animals reject grades and the appearance of skin diseases like The study population animals were extensively managed, almost all “Ekek or cockle” that is mainly due to sheep ked and lice are reared in mixed species herd type as an individually owned infestation (Assefa et al., 2011). The low quality of skins herd or a group based. A total of 900 small ruminants (450 goats undermines the competitiveness of the industry, as it and 450 sheep) were sampled with systematic random sampling. leads to low factor inputs productivity especially in the Ages of animals were addressed in two category, young (below 2 tanning process (Mekonnen et al., 2013). years) and adult (above 2 years) of age according to (Bersisa et al., 2013; Gatenby, 1999). The body condition score (BCS) was Among the diseases of small ruminant skins, considered in three categories, poor (BCS of 1 and 2), medium infestations by mange mites, ticks and infections by pox (BCS of 3) and good (BCS of 4 and 5) according to Desta et al. disease and dermatophilosis possess considerable (2001) and Tefera (2012). economic losses, particularly to the skin export due to various defects (Dessie et al., 2010). Losses from these diseases and other skin abnormalities are leading to Sampling method and sample size downgrading and rejections of skins; unfitness to the Study districts were selected purposively to represent different leather industries (Kebede, 2013; Kumsa et al., 2012). agro-ecology and accessibility whereas study Peasant Associations Skin diseases in small ruminants were reported from (PA) was randomly selected. 10% of shoat herds were selected different parts in Ethiopia. Kumsa et al. (2012) reported from each PA's and individual animals were selected from the the prevalence of 48.1% in central Ethiopia, Dessie et al. population by systematic random sampling approach. The sample (2010) reported a mange mites prevalence in Wolaita size was determined according to Thrusfield, 1995, with expected area of southern Ethiopia 1.98 and 3.85% in sheep and prevalence of 50%, as there were no such study in the area and 95% confidence interval was considered. Despite this, the goats, respectively. A study of tick infestation in small calculated sample size was 380, it was increased to 450 from each ruminants in Bedelle district, Western Ethiopia, revealed species and a total of 900 animals were included in the study. prevalence of 66.12 and 80.7% in goats and sheep, respectively reported by Fufa et al. (2012). Many other studies and reviews conducted at different regions of the Study designs country reported the importance of small ruminant’s skin A cross-sectional study design was employed to estimate the diseases (Kebede, 2013; Yacob, 2013; Assefa et al., prevalence of skin diseases and identify the causal factors for 2012; Tewodros et al., 2012; Dessie et al., 2010; Yacob different skin diseases of small ruminants. The age, sex, species, et al., 2008; Tefera, 2012; Haffiz, 2001; Abadi, 2000). body condition scoring, geographical location, season of the year Despite various study on the prevalence and associated and vaccination were considered as test variables to see if these 230 J. Vet. Med. Anim. Health were risk factors associated with disease occurrence or not. the prevalence was 52.22 and 38.66% in goats and Animals with visible skin problems suspected for bacterial and sheep, respectively. Small ruminants from lowland agro- fungal infections were subjected to skin scrapings. Both skin ecology revealed higher prevalence (43.43%) of skin scrapings and visible external parasites such as ticks, sheep ked and lice were shifted to universal sampling bottle, labelled, diseases than the highland (37.85%) (Tables 1 and 2). preserved and transported to Gofa Universal college department of On species bases, statistically significant (p=0.026) animal health for species identifications and subsequent laboratory variation in prevalence of skin disease was observed on confirmation.