Prevalence of haemoparasites and associated risk factors in working donkeys in Adigudem and Kwiha districts of Tigray region, Northern Ethiopia
B Mekibib, M Manegerew, A Tadesse, F Abuna, B Megersa, A Regassa, S Mekuria, R Abebe
adigudem, donkeys, ethiopia, haemoparasite, kwiha, prevalence, risk factors
B Mekibib, M Manegerew, A Tadesse, F Abuna, B Megersa, A Regassa, S Mekuria, R Abebe. Prevalence of haemoparasites and associated risk factors in working donkeys in Adigudem and Kwiha districts of Tigray region, Northern Ethiopia. The Internet Journal of Veterinary Medicine. 2009 Volume 8 Number 1.
A cross-sectional study was conducted from November 2008 to March 2009 in Adigudem and Kwiha districts of Tigray regional state with the objective of identifying the prevalence of haemoparasites and the associated risk factors in working donkeys. Blood samples were collected from a total of 400 randomly selected donkeys and examined by dark ground/phase contrast buffy coat technique and Giemsa stained blood smears. The overall prevalence of haemoparasites was 2.5% (n =10) without significant variation between the two districts (
The donkey is widely distributed through out Ethiopia with an estimated population of 5.2 million (Saul
Despite the increase in mechanization throughout the world, donkeys are still well deserving of the name ‘beasts of burden’ with their inherent ability to thrive in harsh environments (in arid and semi arid areas and where roads are poor or none existent). They are playing an important role in transportation (riding, pack transport or pulling cart), farming (tillage, threshing) and in certain countries they aid in raising water and milling (Pearson
Recurrent drought in Ethiopia resulting in increased cattle mortality has also contributed to an increase in donkey’s usage as draft and pack animal both in rural and urban areas. In general, donkey has a prominent position in the agricultural system of Ethiopia especially to the resource poor communities in rural and urban areas. The low level of development of the road transport network and rough terrain of the country make the donkey the most valuable, appropriate and affordable pack animal under small holder farming system of Ethiopia (Gebreworld
Despite the number, its prominent role in rural and agricultural life system of the country, the knowledge pertaining to the physiology, nutritional requirement, health problems and management system of the donkey is still limited and rarely available in the literature except the endeavor of the Donkey sanctuary since its establishment.
Even though donkeys have often been described as sturdy animals, they succumb to a variety of infectious and non infectious diseases and a number of other problems (Feseha, 1997). Donkeys harbor several protozoan and metazoan parasites. Among haemoparasitic diseases in donkeys, trypanosomiasis and babesiosis are attributed in reduction in their draughts power efficiency and even their survival (Svendsen, 1997).
In Ethiopia, there are only few published reports about donkey hemoparasites and all the available data are on trypanosomiasis and restricted to only some tsetse infested areas of the country (Kanchula and Abebe, 1997; Assefa and Abebe, 2001; Shelima
Materials and Methods
The study was conducted from November 2008 to March 2009 in Adigudem and Kwiha districts of Tigray regional state, Northern Ethiopia. Adigudem is located at 13 14 50N and 39 to 53 E with an elevation of 2100 m.a.s.l. (Atlas of the Ethiopian Rural economy, 2006). Kwiha, the second site, is located at 13 20 50N and 39 32 38 E with an altitude of 2247 m.a.s.l. Both districts have a cool tropical semiarid climate with mean annual temperature of around 18 °C. The areas are affected by high wind velocity. The mean annual rainfall is about 650mm and varies considerably between years and is characterized by unpredictable drought (Corbeels
In the study area, donkeys comprise indigenous breeds and managed in a traditional extensive way. They are mainly used for draught and pack work types. Most of the owners keep their donkeys in open housing system that does not protect them from extreme weather conditions. The donkeys were housed in stone paved floors without bedding and their manure and wasted feed were not regularly cleaned. The available feed resource for donkeys in these areas constituted natural pasture, concentrates and crop residues.
Study design and sampling method
A cross sectional study was used to achieve the objective of the study. The study animals were selected randomly from those donkeys brought to the Tigray Donkeys Health and Welfare Project (DHWP) mobile clinics. Donkeys of all age groups and both sexes were included in the study. The sample size for the study was determined by using the simple random sampling technique (Thrusfield, 2005). The expected prevalence was taken as 28.5% based on a recent study (Shelima et al., 2006). Thus, a total of 400 donkeys (206 from Adigudem and 194 from Kwiha) which can represent the target population were selected and included in the study. These animals were drawn from a population of donkeys brought to the aforementioned DHWP mobile clinics by applying a lottery method as follows: First all the donkeys in the population were numbered from 1 to N. These numbers were written on the small slips of paper. The slips were placed in a bowl and thoroughly mixed. Then, a blind-folded researcher was allowed to select the required number of samples. Population members having the selected numbers were included in the sample
The age of the selected donkeys was determined using the incisor eruption times and wear (Crane, 1997). Donkeys were grouped into three age categories: donkeys under two years were classed as young (n=57), those in range of two to ten years were classed as adult (n=303) and those beyond ten years were classed as old (n=40).
Body condition scoring (BCS) of the donkeys was performed based on the criteria of NEWC (2005). Hence, grades of A, B and C were given accordingly for good, moderate and poor BCS, respectively.
Parasitological and hematological examination
Blood samples were collected directly from the ear veins using heparinzed microhematocrit capillary tubes and then centrifuged for 5 minutes. The PCV was determined by haematocrit reader and the color of the plasma was simultaneously checked and recorded. The capillary tubes were then cut using a diamond pencil 1 mm below the buffy coat and the contents of the capillary tube were expressed on clean glass slide, mixed and covered with cover slip. Thin smears were prepared directly from the ear vein and also from the buffy coat and fixed with methanol and stained with Giemsa. Both the wet and stained smears were systematically examined for the presence of haemoparasits (Coles, 1986; Urquhart
Blood samples needed for serological investigation of
Data collected from the study animals and laboratory analyses were coded and entered in a Microsoft Excel spread sheet. All statistical analyses were performed using STATA-9 software (Stata Corp. 4905 Lake way drive College Station, TX 77845, USA). The association between prevalence of haemoparasites and the study variables (district, age, sex and BCS) was analyzed by Chi-square (χ2) test of independence, whereas student’s t-test was used to examine the differences in mean PCV between trypanosome/babesia positive and negative animals. In all the analyses, the confidence level was held at 95% and
From the total of 400 donkeys examined in the two districts, 10 animals were found to be infected with Babesia or Trypanosoma. Therefore, the overall prevalence of haemoparasites was 2.5%. On a genus level, the prevalence was 1.75% for
The results of statistical analysis of different risk factors with
The mean PCV value of all donkeys tested was 28.6±5.76%. There was no significant (p>0.05) variation in mean PCV between babesia infected and free animals. In contrast, animals infected with
Of the total 50 sera collected from randomly selected donkeys and sent for serological detection of antibodies against
The prevalence of both
With respect to Babesia, a greater proportion of donkeys were infected with
Ixodid ticks of the genera
In agreement with previous studies (Addisu, 2009, unpublished; Abebe and Wolde, 2010), age and sex of the animals did not have significant influence on the prevalence of haemoparasites. Similarly, no significant variation was found in the prevalence of both
The mean PCV of
Although the number of samples used was small, the serological study revealed that 22% sampled donkeys were seropositive for
In conclusion, this study has revealed the existence of both
The Tigray Donkey Health and Welfare Project staff members are duly acknowledged for their technical and financial support.