MATERIALS AND METHODS
The study was carried out in fourteen districts selected from zone one, four and five of Afar regional state, namely;
Five districts of Zone 1 (AwsiRasu) namely (Afambo, Chifra, Ayssaita, Dubti, Mile), four districts of Zone 5 (HariRasu),
(Telalak, Dewe, Hadalella & Dalifage) and Five districts of Zone 4 (FantenaRasu), (Golina, Awra, Ewa, Yalo & Teru) were
selected for this study. The livestock population in the Afar region estimated at 3.6 million cattle, 2 million sheep, 3
million goats, 0.9 million camels and 0.2 million equines (ERIPAE, 2000). The Afar National Regional State is
characterized by an arid and semi-arid climate with low and erratic rainfall. The altitude of the region ranges from 120m
below sea level to 1500m above sea level. Temperatures vary from 200C in higher elevations to 480C in lower elevations.
Rainfall is bi-modal throughout the region with a mean annual rainfall below 500 mm in the semi-arid western
escarpments and decreasing to 150 mm in the arid zones to the east. The production system of the Afar region is
dominated by pastoralist (90%) from which agro-pastoralist (10%) is now emerging following some permanent and
temporary rivers on which small scale irrigation is developed. The season are traditionally classified as kerma (July-
September), which is the long rainy season; sugum (March-April), which is the short rainy season; hagai (May-June) which
is the hot dry spell; and gilal (October-February) which is the cool season. Gilal is sometimes interrupted by rains in
January and February.
Animals and sampling
A cross-sectional study was used to investigate the occurrence of ecto-parasites in sheep, goats and associated risk
factors. The study was conducted from August-2016 to November-2017, from the three zonal administrations 14
/fourteen districts/were selected for this study. The study districts selected based on the inclusion criteria on the high
sheep and goats population, extent of parasite infection and infestation, accessibility of their Peasant associations and
willingness of the pastoralists to participate in the survey. The studied animals were randomly selected using a systematic
sampling technique from traditionally managed sheep and goats populations in the respective districts. The studied
population was indigenous breed of sheep and goats kept under pastoral type of production which allows free grazing,
usually mixed with other animals.
Sample size determination
Sample size was determined as described by Thrusfield (2005). Accordingly, 50% expected prevalence of
ectoparasites infestations in each study agro-ecology, 5% acceptable error and 95% confidence level was applied to
determine the sample size of study sheep and goats in each study agro-ecology.
n = 1.962pexp (1-pexp)
Where n = sample size, d = desired absolute precision (0.05), Pex = expected prevalence (50%), thus the desired
sample size for Pex = 0.05 is n = 384. Sampling was 384 from each district. Proportionally distributed based on the total
large ruminant population in the study districts and PAs.
Data was collected such as species type, age, sex, and body condition score. The ages of the animals were
estimated using the definition described by Aiello and Mays (1998). When lambs and kids were less than 6 month old,
they were considered as “young animals” whereas when small ruminants were more than 6 month old they were included
in the “adult” group. And also the age determine by using dental formula. Body condition scores will be determined by
modifying the system of Gatenby (2002) animals either poor or good body condition.
Sample collection and handling procedure
During clinical examination the skin will be palpated across all parts of the animal for the presence of ectoparasites,
and gross lesions suggestive of a clinical form of parasitic infestations. Animals found infested will be considered positive.
From sheep and goats ticks, lice and fleas were collected with forceps from their predilection sites of attachment. The
ticks were removed from the host skins whilst retaining their mouth parts for identification using forceps. Coat brushing
techniques was used for collection of lice. They will be placed in labeled universal bottles containing 70% ethanol and
identified under a stereoscopic microscope according to the descriptions of ticks (Walker et al., 2003). When skin lesions
were evidenced skin scraping from suspected cases of mange were collected and preserved in 10% formalin. Mite
Handling, sampling and all of animal related cantacts were in according to ethical regulation standart of Pastoral
and Agro-pastoral Research Institute of Ethiopia.
The collected data were entered in Microsoft excel. An intercooled Stata 7 software (Stata Corporation, 2001)
statistical program was employed for the data analysis. The prevalence of tick was determined by dividing the number of
Citation: Feki E, Gebre S, Shumet A, Gobena Y, Mohammed H, Gebregergious A (2020). Prevalence of ectoparasites in small ruminants (case: afar region of Ethiopia).
Online J. Anim. Feed Res., 10(5): 203-209.